unified project for pcre16 moved to libs

git-svn-id: http://svn.miranda-ng.org/main/trunk@14195 1316c22d-e87f-b044-9b9b-93d7a3e3ba9c

120 files changed, 54362 insertions, 0 deletions

diff --git a/libs/Pcre16/docs/AUTHORS b/libs/Pcre16/docs/AUTHORS
new file mode 100644
index 0000000000..5eee1af4c6
--- /dev/null
+++ b/libs/Pcre16/docs/AUTHORS
@@ -0,0 +1,45 @@
+THE MAIN PCRE LIBRARY
+---------------------
+
+Written by:       Philip Hazel
+Email local part: ph10
+Email domain:     cam.ac.uk
+
+University of Cambridge Computing Service,
+Cambridge, England.
+
+Copyright (c) 1997-2014 University of Cambridge
+All rights reserved
+
+
+PCRE JUST-IN-TIME COMPILATION SUPPORT
+-------------------------------------
+
+Written by:       Zoltan Herczeg
+Email local part: hzmester
+Emain domain:     freemail.hu
+
+Copyright(c) 2010-2014 Zoltan Herczeg
+All rights reserved.
+
+
+STACK-LESS JUST-IN-TIME COMPILER
+--------------------------------
+
+Written by:       Zoltan Herczeg
+Email local part: hzmester
+Emain domain:     freemail.hu
+
+Copyright(c) 2009-2014 Zoltan Herczeg
+All rights reserved.
+
+
+THE C++ WRAPPER LIBRARY
+-----------------------
+
+Written by:       Google Inc.
+
+Copyright (c) 2007-2012 Google Inc
+All rights reserved
+
+####
diff --git a/libs/Pcre16/docs/COPYING b/libs/Pcre16/docs/COPYING
new file mode 100644
index 0000000000..58eed01b61
--- /dev/null
+++ b/libs/Pcre16/docs/COPYING
@@ -0,0 +1,5 @@
+PCRE LICENCE
+
+Please see the file LICENCE in the PCRE distribution for licensing details.
+
+End
diff --git a/libs/Pcre16/docs/ChangeLog b/libs/Pcre16/docs/ChangeLog
new file mode 100644
index 0000000000..7801ef8411
--- /dev/null
+++ b/libs/Pcre16/docs/ChangeLog
@@ -0,0 +1,5477 @@
+ChangeLog for PCRE
+------------------
+
+Version 8.35 04-April-2014
+--------------------------
+
+1.  A new flag is set, when property checks are present in an XCLASS.
+    When this flag is not set, PCRE can perform certain optimizations
+    such as studying these XCLASS-es.
+
+2.  The auto-possessification of character sets were improved: a normal
+    and an extended character set can be compared now. Furthermore
+    the JIT compiler optimizes more character set checks.
+
+3.  Got rid of some compiler warnings for potentially uninitialized variables
+    that show up only when compiled with -O2.
+
+4.  A pattern such as (?=ab\K) that uses \K in an assertion can set the start
+    of a match later then the end of the match. The pcretest program was not
+    handling the case sensibly - it was outputting from the start to the next
+    binary zero. It now reports this situation in a message, and outputs the
+    text from the end to the start.
+
+5.  Fast forward search is improved in JIT. Instead of the first three
+    characters, any three characters with fixed position can be searched.
+    Search order: first, last, middle.
+
+6.  Improve character range checks in JIT. Characters are read by an inprecise
+    function now, which returns with an unknown value if the character code is
+    above a certain treshold (e.g: 256). The only limitation is that the value
+    must be bigger than the treshold as well. This function is useful, when
+    the characters above the treshold are handled in the same way.
+
+7.  The macros whose names start with RAWUCHAR are placeholders for a future
+    mode in which only the bottom 21 bits of 32-bit data items are used. To
+    make this more memorable for those maintaining the code, the names have
+    been changed to start with UCHAR21, and an extensive comment has been added
+    to their definition.
+
+8.  Add missing (new) files sljitNativeTILEGX.c and sljitNativeTILEGX-encoder.c
+    to the export list in Makefile.am (they were accidentally omitted from the
+    8.34 tarball).
+
+9.  The informational output from pcretest used the phrase "starting byte set"
+    which is inappropriate for the 16-bit and 32-bit libraries. As the output
+    for "first char" and "need char" really means "non-UTF-char", I've changed
+    "byte" to "char", and slightly reworded the output. The documentation about
+    these values has also been (I hope) clarified.
+
+10. Another JIT related optimization: use table jumps for selecting the correct
+    backtracking path, when more than four alternatives are present inside a
+    bracket.
+
+11. Empty match is not possible, when the minimum length is greater than zero,
+    and there is no \K in the pattern. JIT should avoid empty match checks in
+    such cases.
+
+12. In a caseless character class with UCP support, when a character with more
+    than one alternative case was not the first character of a range, not all
+    the alternative cases were added to the class. For example, s and \x{17f}
+    are both alternative cases for S: the class [RST] was handled correctly,
+    but [R-T] was not.
+
+13. The configure.ac file always checked for pthread support when JIT was
+    enabled. This is not used in Windows, so I have put this test inside a
+    check for the presence of windows.h (which was already tested for).
+
+14. Improve pattern prefix search by a simplified Boyer-Moore algorithm in JIT.
+    The algorithm provides a way to skip certain starting offsets, and usually
+    faster than linear prefix searches.
+
+15. Change 13 for 8.20 updated RunTest to check for the 'fr' locale as well
+    as for 'fr_FR' and 'french'. For some reason, however, it then used the
+    Windows-specific input and output files, which have 'french' screwed in.
+    So this could never have worked. One of the problems with locales is that
+    they aren't always the same. I have now updated RunTest so that it checks
+    the output of the locale test (test 3) against three different output
+    files, and it allows the test to pass if any one of them matches. With luck
+    this should make the test pass on some versions of Solaris where it was
+    failing. Because of the uncertainty, the script did not used to stop if
+    test 3 failed; it now does. If further versions of a French locale ever
+    come to light, they can now easily be added.
+
+16. If --with-pcregrep-bufsize was given a non-integer value such as "50K",
+    there was a message during ./configure, but it did not stop. This now
+    provokes an error. The invalid example in README has been corrected.
+    If a value less than the minimum is given, the minimum value has always
+    been used, but now a warning is given.
+
+17. If --enable-bsr-anycrlf was set, the special 16/32-bit test failed. This
+    was a bug in the test system, which is now fixed. Also, the list of various
+    configurations that are tested for each release did not have one with both
+    16/32 bits and --enable-bar-anycrlf. It now does.
+
+18. pcretest was missing "-C bsr" for displaying the \R default setting.
+
+19. Little endian PowerPC systems are supported now by the JIT compiler.
+
+20. The fast forward newline mechanism could enter to an infinite loop on
+    certain invalid UTF-8 input. Although we don't support these cases
+    this issue can be fixed by a performance optimization.
+
+21. Change 33 of 8.34 is not sufficient to ensure stack safety because it does
+    not take account if existing stack usage. There is now a new global
+    variable called pcre_stack_guard that can be set to point to an external
+    function to check stack availability. It is called at the start of
+    processing every parenthesized group.
+
+22. A typo in the code meant that in ungreedy mode the max/min qualifier
+    behaved like a min-possessive qualifier, and, for example, /a{1,3}b/U did
+    not match "ab".
+
+23. When UTF was disabled, the JIT program reported some incorrect compile
+    errors. These messages are silenced now.
+
+24. Experimental support for ARM-64 and MIPS-64 has been added to the JIT
+    compiler.
+
+25. Change all the temporary files used in RunGrepTest to be different to those
+    used by RunTest so that the tests can be run simultaneously, for example by
+    "make -j check".
+
+
+Version 8.34 15-December-2013
+-----------------------------
+
+1.  Add pcre[16|32]_jit_free_unused_memory to forcibly free unused JIT
+    executable memory. Patch inspired by Carsten Klein.
+
+2.  ./configure --enable-coverage defined SUPPORT_GCOV in config.h, although
+    this macro is never tested and has no effect, because the work to support
+    coverage involves only compiling and linking options and special targets in
+    the Makefile. The comment in config.h implied that defining the macro would
+    enable coverage support, which is totally false. There was also support for
+    setting this macro in the CMake files (my fault, I just copied it from
+    configure). SUPPORT_GCOV has now been removed.
+
+3.  Make a small performance improvement in strlen16() and strlen32() in
+    pcretest.
+
+4.  Change 36 for 8.33 left some unreachable statements in pcre_exec.c,
+    detected by the Solaris compiler (gcc doesn't seem to be able to diagnose
+    these cases). There was also one in pcretest.c.
+
+5.  Cleaned up a "may be uninitialized" compiler warning in pcre_exec.c.
+
+6.  In UTF mode, the code for checking whether a group could match an empty
+    string (which is used for indefinitely repeated groups to allow for
+    breaking an infinite loop) was broken when the group contained a repeated
+    negated single-character class with a character that occupied more than one
+    data item and had a minimum repetition of zero (for example, [^\x{100}]* in
+    UTF-8 mode). The effect was undefined: the group might or might not be
+    deemed as matching an empty string, or the program might have crashed.
+
+7.  The code for checking whether a group could match an empty string was not
+    recognizing that \h, \H, \v, \V, and \R must match a character.
+
+8.  Implemented PCRE_INFO_MATCH_EMPTY, which yields 1 if the pattern can match
+    an empty string. If it can, pcretest shows this in its information output.
+
+9.  Fixed two related bugs that applied to Unicode extended grapheme clusters
+    that were repeated with a maximizing qualifier (e.g. \X* or \X{2,5}) when
+    matched by pcre_exec() without using JIT:
+
+    (a) If the rest of the pattern did not match after a maximal run of
+        grapheme clusters, the code for backing up to try with fewer of them
+        did not always back up over a full grapheme when characters that do not
+        have the modifier quality were involved, e.g. Hangul syllables.
+
+    (b) If the match point in a subject started with modifier character, and
+        there was no match, the code could incorrectly back up beyond the match
+        point, and potentially beyond the first character in the subject,
+        leading to a segfault or an incorrect match result.
+
+10. A conditional group with an assertion condition could lead to PCRE
+    recording an incorrect first data item for a match if no other first data
+    item was recorded. For example, the pattern (?(?=ab)ab) recorded "a" as a
+    first data item, and therefore matched "ca" after "c" instead of at the
+    start.
+
+11. Change 40 for 8.33 (allowing pcregrep to find empty strings) showed up a
+    bug that caused the command "echo a | ./pcregrep -M '|a'" to loop.
+
+12. The source of pcregrep now includes z/OS-specific code so that it can be
+    compiled for z/OS as part of the special z/OS distribution.
+
+13. Added the -T and -TM options to pcretest.
+
+14. The code in pcre_compile.c for creating the table of named capturing groups
+    has been refactored. Instead of creating the table dynamically during the
+    actual compiling pass, the information is remembered during the pre-compile
+    pass (on the stack unless there are more than 20 named groups, in which
+    case malloc() is used) and the whole table is created before the actual
+    compile happens. This has simplified the code (it is now nearly 150 lines
+    shorter) and prepared the way for better handling of references to groups
+    with duplicate names.
+
+15. A back reference to a named subpattern when there is more than one of the
+    same name now checks them in the order in which they appear in the pattern.
+    The first one that is set is used for the reference. Previously only the
+    first one was inspected. This change makes PCRE more compatible with Perl.
+
+16. Unicode character properties were updated from Unicode 6.3.0.
+
+17. The compile-time code for auto-possessification has been refactored, based
+    on a patch by Zoltan Herczeg. It now happens after instead of during
+    compilation. The code is cleaner, and more cases are handled. The option
+    PCRE_NO_AUTO_POSSESS is added for testing purposes, and the -O and /O
+    options in pcretest are provided to set it. It can also be set by
+    (*NO_AUTO_POSSESS) at the start of a pattern.
+
+18. The character VT has been added to the default ("C" locale) set of
+    characters that match \s and are generally treated as white space,
+    following this same change in Perl 5.18. There is now no difference between
+    "Perl space" and "POSIX space". Whether VT is treated as white space in
+    other locales depends on the locale.
+
+19. The code for checking named groups as conditions, either for being set or
+    for being recursed, has been refactored (this is related to 14 and 15
+    above). Processing unduplicated named groups should now be as fast at
+    numerical groups, and processing duplicated groups should be faster than
+    before.
+
+20. Two patches to the CMake build system, by Alexander Barkov:
+
+      (1) Replace the "source" command by "." in CMakeLists.txt because
+          "source" is a bash-ism.
+
+      (2) Add missing HAVE_STDINT_H and HAVE_INTTYPES_H to config-cmake.h.in;
+          without these the CMake build does not work on Solaris.
+
+21. Perl has changed its handling of \8 and \9. If there is no previously
+    encountered capturing group of those numbers, they are treated as the
+    literal characters 8 and 9 instead of a binary zero followed by the
+    literals. PCRE now does the same.
+
+22. Following Perl, added \o{} to specify codepoints in octal, making it
+    possible to specify values greater than 0777 and also making them
+    unambiguous.
+
+23. Perl now gives an error for missing closing braces after \x{... instead of
+    treating the string as literal. PCRE now does the same.
+
+24. RunTest used to grumble if an inappropriate test was selected explicitly,
+    but just skip it when running all tests. This make it awkward to run ranges
+    of tests when one of them was inappropriate. Now it just skips any
+    inappropriate tests, as it always did when running all tests.
+
+25. If PCRE_AUTO_CALLOUT and PCRE_UCP were set for a pattern that contained
+    character types such as \d or \w, too many callouts were inserted, and the
+    data that they returned was rubbish.
+
+26. In UCP mode, \s was not matching two of the characters that Perl matches,
+    namely NEL (U+0085) and MONGOLIAN VOWEL SEPARATOR (U+180E), though they
+    were matched by \h. The code has now been refactored so that the lists of
+    the horizontal and vertical whitespace characters used for \h and \v (which
+    are defined only in one place) are now also used for \s.
+
+27. Add JIT support for the 64 bit TileGX architecture.
+    Patch by Jiong Wang (Tilera Corporation).
+
+28. Possessive quantifiers for classes (both explicit and automatically
+    generated) now use special opcodes instead of wrapping in ONCE brackets.
+
+29. Whereas an item such as A{4}+ ignored the possessivenes of the quantifier
+    (because it's meaningless), this was not happening when PCRE_CASELESS was
+    set. Not wrong, but inefficient.
+
+30. Updated perltest.pl to add /u (force Unicode mode) when /W (use Unicode
+    properties for \w, \d, etc) is present in a test regex. Otherwise if the
+    test contains no characters greater than 255, Perl doesn't realise it
+    should be using Unicode semantics.
+
+31. Upgraded the handling of the POSIX classes [:graph:], [:print:], and
+    [:punct:] when PCRE_UCP is set so as to include the same characters as Perl
+    does in Unicode mode.
+
+32. Added the "forbid" facility to pcretest so that putting tests into the
+    wrong test files can sometimes be quickly detected.
+
+33. There is now a limit (default 250) on the depth of nesting of parentheses.
+    This limit is imposed to control the amount of system stack used at compile
+    time. It can be changed at build time by --with-parens-nest-limit=xxx or
+    the equivalent in CMake.
+
+34. Character classes such as [A-\d] or [a-[:digit:]] now cause compile-time
+    errors. Perl warns for these when in warning mode, but PCRE has no facility
+    for giving warnings.
+
+35. Change 34 for 8.13 allowed quantifiers on assertions, because Perl does.
+    However, this was not working for (?!) because it is optimized to (*FAIL),
+    for which PCRE does not allow quantifiers. The optimization is now disabled
+    when a quantifier follows (?!). I can't see any use for this, but it makes
+    things uniform.
+
+36. Perl no longer allows group names to start with digits, so I have made this
+    change also in PCRE. It simplifies the code a bit.
+
+37. In extended mode, Perl ignores spaces before a + that indicates a
+    possessive quantifier. PCRE allowed a space before the quantifier, but not
+    before the possessive +. It now does.
+
+38. The use of \K (reset reported match start) within a repeated possessive
+    group such as (a\Kb)*+ was not working.
+
+40. Document that the same character tables must be used at compile time and
+    run time, and that the facility to pass tables to pcre_exec() and
+    pcre_dfa_exec() is for use only with saved/restored patterns.
+
+41. Applied Jeff Trawick's patch CMakeLists.txt, which "provides two new
+    features for Builds with MSVC:
+
+    1. Support pcre.rc and/or pcreposix.rc (as is already done for MinGW
+       builds). The .rc files can be used to set FileDescription and many other
+       attributes.
+
+    2. Add an option (-DINSTALL_MSVC_PDB) to enable installation of .pdb files.
+       This allows higher-level build scripts which want .pdb files to avoid
+       hard-coding the exact files needed."
+
+42. Added support for [[:<:]] and [[:>:]] as used in the BSD POSIX library to
+    mean "start of word" and "end of word", respectively, as a transition aid.
+
+43. A minimizing repeat of a class containing codepoints greater than 255 in
+    non-UTF 16-bit or 32-bit modes caused an internal error when PCRE was
+    compiled to use the heap for recursion.
+
+44. Got rid of some compiler warnings for unused variables when UTF but not UCP
+    is configured.
+
+
+Version 8.33 28-May-2013
+------------------------
+
+1.  Added 'U' to some constants that are compared to unsigned integers, to
+    avoid compiler signed/unsigned warnings. Added (int) casts to unsigned
+    variables that are added to signed variables, to ensure the result is
+    signed and can be negated.
+
+2.  Applied patch by Daniel Richard G for quashing MSVC warnings to the
+    CMake config files.
+
+3.  Revise the creation of config.h.generic so that all boolean macros are
+    #undefined, whereas non-boolean macros are #ifndef/#endif-ed. This makes
+    overriding via -D on the command line possible.
+
+4.  Changing the definition of the variable "op" in pcre_exec.c from pcre_uchar
+    to unsigned int is reported to make a quite noticeable speed difference in
+    a specific Windows environment. Testing on Linux did also appear to show
+    some benefit (and it is clearly not harmful). Also fixed the definition of
+    Xop which should be unsigned.
+
+5.  Related to (4), changing the definition of the intermediate variable cc
+    in repeated character loops from pcre_uchar to pcre_uint32 also gave speed
+    improvements.
+
+6.  Fix forward search in JIT when link size is 3 or greater. Also removed some
+    unnecessary spaces.
+
+7.  Adjust autogen.sh and configure.ac to lose warnings given by automake 1.12
+    and later.
+
+8.  Fix two buffer over read issues in 16 and 32 bit modes. Affects JIT only.
+
+9.  Optimizing fast_forward_start_bits in JIT.
+
+10. Adding support for callouts in JIT, and fixing some issues revealed
+    during this work. Namely:
+
+    (a) Unoptimized capturing brackets incorrectly reset on backtrack.
+
+    (b) Minimum length was not checked before the matching is started.
+
+11. The value of capture_last that is passed to callouts was incorrect in some
+    cases when there was a capture on one path that was subsequently abandoned
+    after a backtrack. Also, the capture_last value is now reset after a
+    recursion, since all captures are also reset in this case.
+
+12. The interpreter no longer returns the "too many substrings" error in the
+    case when an overflowing capture is in a branch that is subsequently
+    abandoned after a backtrack.
+
+13. In the pathological case when an offset vector of size 2 is used, pcretest
+    now prints out the matched string after a yield of 0 or 1.
+
+14. Inlining subpatterns in recursions, when certain conditions are fulfilled.
+    Only supported by the JIT compiler at the moment.
+
+15. JIT compiler now supports 32 bit Macs thanks to Lawrence Velazquez.
+
+16. Partial matches now set offsets[2] to the "bumpalong" value, that is, the
+    offset of the starting point of the matching process, provided the offsets
+    vector is large enough.
+
+17. The \A escape now records a lookbehind value of 1, though its execution
+    does not actually inspect the previous character. This is to ensure that,
+    in partial multi-segment matching, at least one character from the old
+    segment is retained when a new segment is processed. Otherwise, if there
+    are no lookbehinds in the pattern, \A might match incorrectly at the start
+    of a new segment.
+
+18. Added some #ifdef __VMS code into pcretest.c to help VMS implementations.
+
+19. Redefined some pcre_uchar variables in pcre_exec.c as pcre_uint32; this
+    gives some modest performance improvement in 8-bit mode.
+
+20. Added the PCRE-specific property \p{Xuc} for matching characters that can
+    be expressed in certain programming languages using Universal Character
+    Names.
+
+21. Unicode validation has been updated in the light of Unicode Corrigendum #9,
+    which points out that "non characters" are not "characters that may not
+    appear in Unicode strings" but rather "characters that are reserved for
+    internal use and have only local meaning".
+
+22. When a pattern was compiled with automatic callouts (PCRE_AUTO_CALLOUT) and
+    there was a conditional group that depended on an assertion, if the
+    assertion was false, the callout that immediately followed the alternation
+    in the condition was skipped when pcre_exec() was used for matching.
+
+23. Allow an explicit callout to be inserted before an assertion that is the
+    condition for a conditional group, for compatibility with automatic
+    callouts, which always insert a callout at this point.
+
+24. In 8.31, (*COMMIT) was confined to within a recursive subpattern. Perl also
+    confines (*SKIP) and (*PRUNE) in the same way, and this has now been done.
+
+25. (*PRUNE) is now supported by the JIT compiler.
+
+26. Fix infinite loop when /(?<=(*SKIP)ac)a/ is matched against aa.
+
+27. Fix the case where there are two or more SKIPs with arguments that may be
+    ignored.
+
+28. (*SKIP) is now supported by the JIT compiler.
+
+29. (*THEN) is now supported by the JIT compiler.
+
+30. Update RunTest with additional test selector options.
+
+31. The way PCRE handles backtracking verbs has been changed in two ways.
+
+    (1) Previously, in something like (*COMMIT)(*SKIP), COMMIT would override
+    SKIP. Now, PCRE acts on whichever backtracking verb is reached first by
+    backtracking. In some cases this makes it more Perl-compatible, but Perl's
+    rather obscure rules do not always do the same thing.
+
+    (2) Previously, backtracking verbs were confined within assertions. This is
+    no longer the case for positive assertions, except for (*ACCEPT). Again,
+    this sometimes improves Perl compatibility, and sometimes does not.
+
+32. A number of tests that were in test 2 because Perl did things differently
+    have been moved to test 1, because either Perl or PCRE has changed, and
+    these tests are now compatible.
+
+32. Backtracking control verbs are now handled in the same way in JIT and
+    interpreter.
+
+33. An opening parenthesis in a MARK/PRUNE/SKIP/THEN name in a pattern that
+    contained a forward subroutine reference caused a compile error.
+
+34. Auto-detect and optimize limited repetitions in JIT.
+
+35. Implement PCRE_NEVER_UTF to lock out the use of UTF, in particular,
+    blocking (*UTF) etc.
+
+36. In the interpreter, maximizing pattern repetitions for characters and
+    character types now use tail recursion, which reduces stack usage.
+
+37. The value of the max lookbehind was not correctly preserved if a compiled
+    and saved regex was reloaded on a host of different endianness.
+
+38. Implemented (*LIMIT_MATCH) and (*LIMIT_RECURSION). As part of the extension
+    of the compiled pattern block, expand the flags field from 16 to 32 bits
+    because it was almost full.
+
+39. Try madvise first before posix_madvise.
+
+40. Change 7 for PCRE 7.9 made it impossible for pcregrep to find empty lines
+    with a pattern such as ^$. It has taken 4 years for anybody to notice! The
+    original change locked out all matches of empty strings. This has been
+    changed so that one match of an empty string per line is recognized.
+    Subsequent searches on the same line (for colouring or for --only-matching,
+    for example) do not recognize empty strings.
+
+41. Applied a user patch to fix a number of spelling mistakes in comments.
+
+42. Data lines longer than 65536 caused pcretest to crash.
+
+43. Clarified the data type for length and startoffset arguments for pcre_exec
+    and pcre_dfa_exec in the function-specific man pages, where they were
+    explicitly stated to be in bytes, never having been updated. I also added
+    some clarification to the pcreapi man page.
+
+44. A call to pcre_dfa_exec() with an output vector size less than 2 caused
+    a segmentation fault.
+
+
+Version 8.32 30-November-2012
+-----------------------------
+
+1.  Improved JIT compiler optimizations for first character search and single
+    character iterators.
+
+2.  Supporting IBM XL C compilers for PPC architectures in the JIT compiler.
+    Patch by Daniel Richard G.
+
+3.  Single character iterator optimizations in the JIT compiler.
+
+4.  Improved JIT compiler optimizations for character ranges.
+
+5.  Rename the "leave" variable names to "quit" to improve WinCE compatibility.
+    Reported by Giuseppe D'Angelo.
+
+6.  The PCRE_STARTLINE bit, indicating that a match can occur only at the start
+    of a line, was being set incorrectly in cases where .* appeared inside
+    atomic brackets at the start of a pattern, or where there was a subsequent
+    *PRUNE or *SKIP.
+
+7.  Improved instruction cache flush for POWER/PowerPC.
+    Patch by Daniel Richard G.
+
+8.  Fixed a number of issues in pcregrep, making it more compatible with GNU
+    grep:
+
+    (a) There is now no limit to the number of patterns to be matched.
+
+    (b) An error is given if a pattern is too long.
+
+    (c) Multiple uses of --exclude, --exclude-dir, --include, and --include-dir
+        are now supported.
+
+    (d) --exclude-from and --include-from (multiple use) have been added.
+
+    (e) Exclusions and inclusions now apply to all files and directories, not
+        just to those obtained from scanning a directory recursively.
+
+    (f) Multiple uses of -f and --file-list are now supported.
+
+    (g) In a Windows environment, the default for -d has been changed from
+        "read" (the GNU grep default) to "skip", because otherwise the presence
+        of a directory in the file list provokes an error.
+
+    (h) The documentation has been revised and clarified in places.
+
+9.  Improve the matching speed of capturing brackets.
+
+10. Changed the meaning of \X so that it now matches a Unicode extended
+    grapheme cluster.
+
+11. Patch by Daniel Richard G to the autoconf files to add a macro for sorting
+    out POSIX threads when JIT support is configured.
+
+12. Added support for PCRE_STUDY_EXTRA_NEEDED.
+
+13. In the POSIX wrapper regcomp() function, setting re_nsub field in the preg
+    structure could go wrong in environments where size_t is not the same size
+    as int.
+
+14. Applied user-supplied patch to pcrecpp.cc to allow PCRE_NO_UTF8_CHECK to be
+    set.
+
+15. The EBCDIC support had decayed; later updates to the code had included
+    explicit references to (e.g.) \x0a instead of CHAR_LF. There has been a
+    general tidy up of EBCDIC-related issues, and the documentation was also
+    not quite right. There is now a test that can be run on ASCII systems to
+    check some of the EBCDIC-related things (but is it not a full test).
+
+16. The new PCRE_STUDY_EXTRA_NEEDED option is now used by pcregrep, resulting
+    in a small tidy to the code.
+
+17. Fix JIT tests when UTF is disabled and both 8 and 16 bit mode are enabled.
+
+18. If the --only-matching (-o) option in pcregrep is specified multiple
+    times, each one causes appropriate output. For example, -o1 -o2 outputs the
+    substrings matched by the 1st and 2nd capturing parentheses. A separating
+    string can be specified by --om-separator (default empty).
+
+19. Improving the first n character searches.
+
+20. Turn case lists for horizontal and vertical white space into macros so that
+    they are defined only once.
+
+21. This set of changes together give more compatible Unicode case-folding
+    behaviour for characters that have more than one other case when UCP
+    support is available.
+
+    (a) The Unicode property table now has offsets into a new table of sets of
+        three or more characters that are case-equivalent. The MultiStage2.py
+        script that generates these tables (the pcre_ucd.c file) now scans
+        CaseFolding.txt instead of UnicodeData.txt for character case
+        information.
+
+    (b) The code for adding characters or ranges of characters to a character
+        class has been abstracted into a generalized function that also handles
+        case-independence. In UTF-mode with UCP support, this uses the new data
+        to handle characters with more than one other case.
+
+    (c) A bug that is fixed as a result of (b) is that codepoints less than 256
+        whose other case is greater than 256 are now correctly matched
+        caselessly. Previously, the high codepoint matched the low one, but not
+        vice versa.
+
+    (d) The processing of \h, \H, \v, and \ in character classes now makes use
+        of the new class addition function, using character lists defined as
+        macros alongside the case definitions of 20 above.
+
+    (e) Caseless back references now work with characters that have more than
+        one other case.
+
+    (f) General caseless matching of characters with more than one other case
+        is supported.
+
+22. Unicode character properties were updated from Unicode 6.2.0
+
+23. Improved CMake support under Windows. Patch by Daniel Richard G.
+
+24. Add support for 32-bit character strings, and UTF-32
+
+25. Major JIT compiler update (code refactoring and bugfixing).
+    Experimental Sparc 32 support is added.
+
+26. Applied a modified version of Daniel Richard G's patch to create
+    pcre.h.generic and config.h.generic by "make" instead of in the
+    PrepareRelease script.
+
+27. Added a definition for CHAR_NULL (helpful for the z/OS port), and use it in
+    pcre_compile.c when checking for a zero character.
+
+28. Introducing a native interface for JIT. Through this interface, the compiled
+    machine code can be directly executed. The purpose of this interface is to
+    provide fast pattern matching, so several sanity checks are not performed.
+    However, feature tests are still performed. The new interface provides
+    1.4x speedup compared to the old one.
+
+29. If pcre_exec() or pcre_dfa_exec() was called with a negative value for
+    the subject string length, the error given was PCRE_ERROR_BADOFFSET, which
+    was confusing. There is now a new error PCRE_ERROR_BADLENGTH for this case.
+
+30. In 8-bit UTF-8 mode, pcretest failed to give an error for data codepoints
+    greater than 0x7fffffff (which cannot be represented in UTF-8, even under
+    the "old" RFC 2279). Instead, it ended up passing a negative length to
+    pcre_exec().
+
+31. Add support for GCC's visibility feature to hide internal functions.
+
+32. Running "pcretest -C pcre8" or "pcretest -C pcre16" gave a spurious error
+    "unknown -C option" after outputting 0 or 1.
+
+33. There is now support for generating a code coverage report for the test
+    suite in environments where gcc is the compiler and lcov is installed. This
+    is mainly for the benefit of the developers.
+
+34. If PCRE is built with --enable-valgrind, certain memory regions are marked
+    unaddressable using valgrind annotations, allowing valgrind to detect
+    invalid memory accesses. This is mainly for the benefit of the developers.
+
+25. (*UTF) can now be used to start a pattern in any of the three libraries.
+
+26. Give configure error if --enable-cpp but no C++ compiler found.
+
+
+Version 8.31 06-July-2012
+-------------------------
+
+1.  Fixing a wrong JIT test case and some compiler warnings.
+
+2.  Removed a bashism from the RunTest script.
+
+3.  Add a cast to pcre_exec.c to fix the warning "unary minus operator applied
+    to unsigned type, result still unsigned" that was given by an MS compiler
+    on encountering the code "-sizeof(xxx)".
+
+4.  Partial matching support is added to the JIT compiler.
+
+5.  Fixed several bugs concerned with partial matching of items that consist
+    of more than one character:
+
+    (a) /^(..)\1/ did not partially match "aba" because checking references was
+        done on an "all or nothing" basis. This also applied to repeated
+        references.
+
+    (b) \R did not give a hard partial match if \r was found at the end of the
+        subject.
+
+    (c) \X did not give a hard partial match after matching one or more
+        characters at the end of the subject.
+
+    (d) When newline was set to CRLF, a pattern such as /a$/ did not recognize
+        a partial match for the string "\r".
+
+    (e) When newline was set to CRLF, the metacharacter "." did not recognize
+        a partial match for a CR character at the end of the subject string.
+
+6.  If JIT is requested using /S++ or -s++ (instead of just /S+ or -s+) when
+    running pcretest, the text "(JIT)" added to the output whenever JIT is
+    actually used to run the match.
+
+7.  Individual JIT compile options can be set in pcretest by following -s+[+]
+    or /S+[+] with a digit between 1 and 7.
+
+8.  OP_NOT now supports any UTF character not just single-byte ones.
+
+9.  (*MARK) control verb is now supported by the JIT compiler.
+
+10. The command "./RunTest list" lists the available tests without actually
+    running any of them. (Because I keep forgetting what they all are.)
+
+11. Add PCRE_INFO_MAXLOOKBEHIND.
+
+12. Applied a (slightly modified) user-supplied patch that improves performance
+    when the heap is used for recursion (compiled with --disable-stack-for-
+    recursion). Instead of malloc and free for each heap frame each time a
+    logical recursion happens, frames are retained on a chain and re-used where
+    possible. This sometimes gives as much as 30% improvement.
+
+13. As documented, (*COMMIT) is now confined to within a recursive subpattern
+    call.
+
+14. As documented, (*COMMIT) is now confined to within a positive assertion.
+
+15. It is now possible to link pcretest with libedit as an alternative to
+    libreadline.
+
+16. (*COMMIT) control verb is now supported by the JIT compiler.
+
+17. The Unicode data tables have been updated to Unicode 6.1.0.
+
+18. Added --file-list option to pcregrep.
+
+19. Added binary file support to pcregrep, including the -a, --binary-files,
+    -I, and --text options.
+
+20. The madvise function is renamed for posix_madvise for QNX compatibility
+    reasons. Fixed by Giuseppe D'Angelo.
+
+21. Fixed a bug for backward assertions with REVERSE 0 in the JIT compiler.
+
+22. Changed the option for creating symbolic links for 16-bit man pages from
+    -s to -sf so that re-installing does not cause issues.
+
+23. Support PCRE_NO_START_OPTIMIZE in JIT as (*MARK) support requires it.
+
+24. Fixed a very old bug in pcretest that caused errors with restarted DFA
+    matches in certain environments (the workspace was not being correctly
+    retained). Also added to pcre_dfa_exec() a simple plausibility check on
+    some of the workspace data at the beginning of a restart.
+
+25. \s*\R was auto-possessifying the \s* when it should not, whereas \S*\R
+    was not doing so when it should - probably a typo introduced by SVN 528
+    (change 8.10/14).
+
+26. When PCRE_UCP was not set, \w+\x{c4} was incorrectly auto-possessifying the
+    \w+ when the character tables indicated that \x{c4} was a word character.
+    There were several related cases, all because the tests for doing a table
+    lookup were testing for characters less than 127 instead of 255.
+
+27. If a pattern contains capturing parentheses that are not used in a match,
+    their slots in the ovector are set to -1. For those that are higher than
+    any matched groups, this happens at the end of processing. In the case when
+    there were back references that the ovector was too small to contain
+    (causing temporary malloc'd memory to be used during matching), and the
+    highest capturing number was not used, memory off the end of the ovector
+    was incorrectly being set to -1. (It was using the size of the temporary
+    memory instead of the true size.)
+
+28. To catch bugs like 27 using valgrind, when pcretest is asked to specify an
+    ovector size, it uses memory at the end of the block that it has got.
+
+29. Check for an overlong MARK name and give an error at compile time. The
+    limit is 255 for the 8-bit library and 65535 for the 16-bit library.
+
+30. JIT compiler update.
+
+31. JIT is now supported on jailbroken iOS devices. Thanks for Ruiger
+    Rill for the patch.
+
+32. Put spaces around SLJIT_PRINT_D in the JIT compiler. Required by CXX11.
+
+33. Variable renamings in the PCRE-JIT compiler. No functionality change.
+
+34. Fixed typos in pcregrep: in two places there was SUPPORT_LIBZ2 instead of
+    SUPPORT_LIBBZ2. This caused a build problem when bzip2 but not gzip (zlib)
+    was enabled.
+
+35. Improve JIT code generation for greedy plus quantifier.
+
+36. When /((?:a?)*)*c/ or /((?>a?)*)*c/ was matched against "aac", it set group
+    1 to "aa" instead of to an empty string. The bug affected repeated groups
+    that could potentially match an empty string.
+
+37. Optimizing single character iterators in JIT.
+
+38. Wide characters specified with \uxxxx in JavaScript mode are now subject to
+    the same checks as \x{...} characters in non-JavaScript mode. Specifically,
+    codepoints that are too big for the mode are faulted, and in a UTF mode,
+    disallowed codepoints are also faulted.
+
+39. If PCRE was compiled with UTF support, in three places in the DFA
+    matcher there was code that should only have been obeyed in UTF mode, but
+    was being obeyed unconditionally. In 8-bit mode this could cause incorrect
+    processing when bytes with values greater than 127 were present. In 16-bit
+    mode the bug would be provoked by values in the range 0xfc00 to 0xdc00. In
+    both cases the values are those that cannot be the first data item in a UTF
+    character. The three items that might have provoked this were recursions,
+    possessively repeated groups, and atomic groups.
+
+40. Ensure that libpcre is explicitly listed in the link commands for pcretest
+    and pcregrep, because some OS require shared objects to be explicitly
+    passed to ld, causing the link step to fail if they are not.
+
+41. There were two incorrect #ifdefs in pcre_study.c, meaning that, in 16-bit
+    mode, patterns that started with \h* or \R* might be incorrectly matched.
+
+
+Version 8.30 04-February-2012
+-----------------------------
+
+1.  Renamed "isnumber" as "is_a_number" because in some Mac environments this
+    name is defined in ctype.h.
+
+2.  Fixed a bug in fixed-length calculation for lookbehinds that would show up
+    only in quite long subpatterns.
+
+3.  Removed the function pcre_info(), which has been obsolete and deprecated
+    since it was replaced by pcre_fullinfo() in February 2000.
+
+4.  For a non-anchored pattern, if (*SKIP) was given with a name that did not
+    match a (*MARK), and the match failed at the start of the subject, a
+    reference to memory before the start of the subject could occur. This bug
+    was introduced by fix 17 of release 8.21.
+
+5.  A reference to an unset group with zero minimum repetition was giving
+    totally wrong answers (in non-JavaScript-compatibility mode). For example,
+    /(another)?(\1?)test/ matched against "hello world test". This bug was
+    introduced in release 8.13.
+
+6.  Add support for 16-bit character strings (a large amount of work involving
+    many changes and refactorings).
+
+7.  RunGrepTest failed on msys because \r\n was replaced by whitespace when the
+    command "pattern=`printf 'xxx\r\njkl'`" was run. The pattern is now taken
+    from a file.
+
+8.  Ovector size of 2 is also supported by JIT based pcre_exec (the ovector size
+    rounding is not applied in this particular case).
+
+9.  The invalid Unicode surrogate codepoints U+D800 to U+DFFF are now rejected
+    if they appear, or are escaped, in patterns.
+
+10. Get rid of a number of -Wunused-but-set-variable warnings.
+
+11. The pattern /(?=(*:x))(q|)/ matches an empty string, and returns the mark
+    "x". The similar pattern /(?=(*:x))((*:y)q|)/ did not return a mark at all.
+    Oddly, Perl behaves the same way. PCRE has been fixed so that this pattern
+    also returns the mark "x". This bug applied to capturing parentheses,
+    non-capturing parentheses, and atomic parentheses. It also applied to some
+    assertions.
+
+12. Stephen Kelly's patch to CMakeLists.txt allows it to parse the version
+    information out of configure.ac instead of relying on pcre.h.generic, which
+    is not stored in the repository.
+
+13. Applied Dmitry V. Levin's patch for a more portable method for linking with
+    -lreadline.
+
+14. ZH added PCRE_CONFIG_JITTARGET; added its output to pcretest -C.
+
+15. Applied Graycode's patch to put the top-level frame on the stack rather
+    than the heap when not using the stack for recursion. This gives a
+    performance improvement in many cases when recursion is not deep.
+
+16. Experimental code added to "pcretest -C" to output the stack frame size.
+
+
+Version 8.21 12-Dec-2011
+------------------------
+
+1.  Updating the JIT compiler.
+
+2.  JIT compiler now supports OP_NCREF, OP_RREF and OP_NRREF. New test cases
+    are added as well.
+
+3.  Fix cache-flush issue on PowerPC (It is still an experimental JIT port).
+    PCRE_EXTRA_TABLES is not suported by JIT, and should be checked before
+    calling _pcre_jit_exec. Some extra comments are added.
+
+4.  (*MARK) settings inside atomic groups that do not contain any capturing
+    parentheses, for example, (?>a(*:m)), were not being passed out. This bug
+    was introduced by change 18 for 8.20.
+
+5.  Supporting of \x, \U and \u in JavaScript compatibility mode based on the
+    ECMA-262 standard.
+
+6.  Lookbehinds such as (?<=a{2}b) that contained a fixed repetition were
+    erroneously being rejected as "not fixed length" if PCRE_CASELESS was set.
+    This bug was probably introduced by change 9 of 8.13.
+
+7.  While fixing 6 above, I noticed that a number of other items were being
+    incorrectly rejected as "not fixed length". This arose partly because newer
+    opcodes had not been added to the fixed-length checking code. I have (a)
+    corrected the bug and added tests for these items, and (b) arranged for an
+    error to occur if an unknown opcode is encountered while checking for fixed
+    length instead of just assuming "not fixed length". The items that were
+    rejected were: (*ACCEPT), (*COMMIT), (*FAIL), (*MARK), (*PRUNE), (*SKIP),
+    (*THEN), \h, \H, \v, \V, and single character negative classes with fixed
+    repetitions, e.g. [^a]{3}, with and without PCRE_CASELESS.
+
+8.  A possessively repeated conditional subpattern such as (?(?=c)c|d)++ was
+    being incorrectly compiled and would have given unpredicatble results.
+
+9.  A possessively repeated subpattern with minimum repeat count greater than
+    one behaved incorrectly. For example, (A){2,}+ behaved as if it was
+    (A)(A)++ which meant that, after a subsequent mismatch, backtracking into
+    the first (A) could occur when it should not.
+
+10. Add a cast and remove a redundant test from the code.
+
+11. JIT should use pcre_malloc/pcre_free for allocation.
+
+12. Updated pcre-config so that it no longer shows -L/usr/lib, which seems
+    best practice nowadays, and helps with cross-compiling. (If the exec_prefix
+    is anything other than /usr, -L is still shown).
+
+13. In non-UTF-8 mode, \C is now supported in lookbehinds and DFA matching.
+
+14. Perl does not support \N without a following name in a [] class; PCRE now
+    also gives an error.
+
+15. If a forward reference was repeated with an upper limit of around 2000,
+    it caused the error "internal error: overran compiling workspace". The
+    maximum number of forward references (including repeats) was limited by the
+    internal workspace, and dependent on the LINK_SIZE. The code has been
+    rewritten so that the workspace expands (via pcre_malloc) if necessary, and
+    the default depends on LINK_SIZE. There is a new upper limit (for safety)
+    of around 200,000 forward references. While doing this, I also speeded up
+    the filling in of repeated forward references.
+
+16. A repeated forward reference in a pattern such as (a)(?2){2}(.) was
+    incorrectly expecting the subject to contain another "a" after the start.
+
+17. When (*SKIP:name) is activated without a corresponding (*MARK:name) earlier
+    in the match, the SKIP should be ignored. This was not happening; instead
+    the SKIP was being treated as NOMATCH. For patterns such as
+    /A(*MARK:A)A+(*SKIP:B)Z|AAC/ this meant that the AAC branch was never
+    tested.
+
+18. The behaviour of (*MARK), (*PRUNE), and (*THEN) has been reworked and is
+    now much more compatible with Perl, in particular in cases where the result
+    is a non-match for a non-anchored pattern. For example, if
+    /b(*:m)f|a(*:n)w/ is matched against "abc", the non-match returns the name
+    "m", where previously it did not return a name. A side effect of this
+    change is that for partial matches, the last encountered mark name is
+    returned, as for non matches. A number of tests that were previously not
+    Perl-compatible have been moved into the Perl-compatible test files. The
+    refactoring has had the pleasing side effect of removing one argument from
+    the match() function, thus reducing its stack requirements.
+
+19. If the /S+ option was used in pcretest to study a pattern using JIT,
+    subsequent uses of /S (without +) incorrectly behaved like /S+.
+
+21. Retrieve executable code size support for the JIT compiler and fixing
+    some warnings.
+
+22. A caseless match of a UTF-8 character whose other case uses fewer bytes did
+    not work when the shorter character appeared right at the end of the
+    subject string.
+
+23. Added some (int) casts to non-JIT modules to reduce warnings on 64-bit
+    systems.
+
+24. Added PCRE_INFO_JITSIZE to pass on the value from (21) above, and also
+    output it when the /M option is used in pcretest.
+
+25. The CheckMan script was not being included in the distribution. Also, added
+    an explicit "perl" to run Perl scripts from the PrepareRelease script
+    because this is reportedly needed in Windows.
+
+26. If study data was being save in a file and studying had not found a set of
+    "starts with" bytes for the pattern, the data written to the file (though
+    never used) was taken from uninitialized memory and so caused valgrind to
+    complain.
+
+27. Updated RunTest.bat as provided by Sheri Pierce.
+
+28. Fixed a possible uninitialized memory bug in pcre_jit_compile.c.
+
+29. Computation of memory usage for the table of capturing group names was
+    giving an unnecessarily large value.
+
+
+Version 8.20 21-Oct-2011
+------------------------
+
+1.  Change 37 of 8.13 broke patterns like [:a]...[b:] because it thought it had
+    a POSIX class. After further experiments with Perl, which convinced me that
+    Perl has bugs and confusions, a closing square bracket is no longer allowed
+    in a POSIX name. This bug also affected patterns with classes that started
+    with full stops.
+
+2.  If a pattern such as /(a)b|ac/ is matched against "ac", there is no
+    captured substring, but while checking the failing first alternative,
+    substring 1 is temporarily captured. If the output vector supplied to
+    pcre_exec() was not big enough for this capture, the yield of the function
+    was still zero ("insufficient space for captured substrings"). This cannot
+    be totally fixed without adding another stack variable, which seems a lot
+    of expense for a edge case. However, I have improved the situation in cases
+    such as /(a)(b)x|abc/ matched against "abc", where the return code
+    indicates that fewer than the maximum number of slots in the ovector have
+    been set.
+
+3.  Related to (2) above: when there are more back references in a pattern than
+    slots in the output vector, pcre_exec() uses temporary memory during
+    matching, and copies in the captures as far as possible afterwards. It was
+    using the entire output vector, but this conflicts with the specification
+    that only 2/3 is used for passing back captured substrings. Now it uses
+    only the first 2/3, for compatibility. This is, of course, another edge
+    case.
+
+4.  Zoltan Herczeg's just-in-time compiler support has been integrated into the
+    main code base, and can be used by building with --enable-jit. When this is
+    done, pcregrep automatically uses it unless --disable-pcregrep-jit or the
+    runtime --no-jit option is given.
+
+5.  When the number of matches in a pcre_dfa_exec() run exactly filled the
+    ovector, the return from the function was zero, implying that there were
+    other matches that did not fit. The correct "exactly full" value is now
+    returned.
+
+6.  If a subpattern that was called recursively or as a subroutine contained
+    (*PRUNE) or any other control that caused it to give a non-standard return,
+    invalid errors such as "Error -26 (nested recursion at the same subject
+    position)" or even infinite loops could occur.
+
+7.  If a pattern such as /a(*SKIP)c|b(*ACCEPT)|/ was studied, it stopped
+    computing the minimum length on reaching *ACCEPT, and so ended up with the
+    wrong value of 1 rather than 0. Further investigation indicates that
+    computing a minimum subject length in the presence of *ACCEPT is difficult
+    (think back references, subroutine calls), and so I have changed the code
+    so that no minimum is registered for a pattern that contains *ACCEPT.
+
+8.  If (*THEN) was present in the first (true) branch of a conditional group,
+    it was not handled as intended. [But see 16 below.]
+
+9.  Replaced RunTest.bat and CMakeLists.txt with improved versions provided by
+    Sheri Pierce.
+
+10. A pathological pattern such as /(*ACCEPT)a/ was miscompiled, thinking that
+    the first byte in a match must be "a".
+
+11. Change 17 for 8.13 increased the recursion depth for patterns like
+    /a(?:.)*?a/ drastically. I've improved things by remembering whether a
+    pattern contains any instances of (*THEN). If it does not, the old
+    optimizations are restored. It would be nice to do this on a per-group
+    basis, but at the moment that is not feasible.
+
+12. In some environments, the output of pcretest -C is CRLF terminated. This
+    broke RunTest's code that checks for the link size. A single white space
+    character after the value is now allowed for.
+
+13. RunTest now checks for the "fr" locale as well as for "fr_FR" and "french".
+    For "fr", it uses the Windows-specific input and output files.
+
+14. If (*THEN) appeared in a group that was called recursively or as a
+    subroutine, it did not work as intended. [But see next item.]
+
+15. Consider the pattern /A (B(*THEN)C) | D/ where A, B, C, and D are complex
+    pattern fragments (but not containing any | characters). If A and B are
+    matched, but there is a failure in C so that it backtracks to (*THEN), PCRE
+    was behaving differently to Perl. PCRE backtracked into A, but Perl goes to
+    D. In other words, Perl considers parentheses that do not contain any |
+    characters to be part of a surrounding alternative, whereas PCRE was
+    treading (B(*THEN)C) the same as (B(*THEN)C|(*FAIL)) -- which Perl handles
+    differently. PCRE now behaves in the same way as Perl, except in the case
+    of subroutine/recursion calls such as (?1) which have in any case always
+    been different (but PCRE had them first :-).
+
+16. Related to 15 above: Perl does not treat the | in a conditional group as
+    creating alternatives. Such a group is treated in the same way as an
+    ordinary group without any | characters when processing (*THEN). PCRE has
+    been changed to match Perl's behaviour.
+
+17. If a user had set PCREGREP_COLO(U)R to something other than 1:31, the
+    RunGrepTest script failed.
+
+18. Change 22 for version 13 caused atomic groups to use more stack. This is
+    inevitable for groups that contain captures, but it can lead to a lot of
+    stack use in large patterns. The old behaviour has been restored for atomic
+    groups that do not contain any capturing parentheses.
+
+19. If the PCRE_NO_START_OPTIMIZE option was set for pcre_compile(), it did not
+    suppress the check for a minimum subject length at run time. (If it was
+    given to pcre_exec() or pcre_dfa_exec() it did work.)
+
+20. Fixed an ASCII-dependent infelicity in pcretest that would have made it
+    fail to work when decoding hex characters in data strings in EBCDIC
+    environments.
+
+21. It appears that in at least one Mac OS environment, the isxdigit() function
+    is implemented as a macro that evaluates to its argument more than once,
+    contravening the C 90 Standard (I haven't checked a later standard). There
+    was an instance in pcretest which caused it to go wrong when processing
+    \x{...} escapes in subject strings. The has been rewritten to avoid using
+    things like p++ in the argument of isxdigit().
+
+
+Version 8.13 16-Aug-2011
+------------------------
+
+1.  The Unicode data tables have been updated to Unicode 6.0.0.
+
+2.  Two minor typos in pcre_internal.h have been fixed.
+
+3.  Added #include <string.h> to pcre_scanner_unittest.cc, pcrecpp.cc, and
+    pcrecpp_unittest.cc. They are needed for strcmp(), memset(), and strchr()
+    in some environments (e.g. Solaris 10/SPARC using Sun Studio 12U2).
+
+4.  There were a number of related bugs in the code for matching backrefences
+    caselessly in UTF-8 mode when codes for the characters concerned were
+    different numbers of bytes. For example, U+023A and U+2C65 are an upper
+    and lower case pair, using 2 and 3 bytes, respectively. The main bugs were:
+    (a) A reference to 3 copies of a 2-byte code matched only 2 of a 3-byte
+    code. (b) A reference to 2 copies of a 3-byte code would not match 2 of a
+    2-byte code at the end of the subject (it thought there wasn't enough data
+    left).
+
+5.  Comprehensive information about what went wrong is now returned by
+    pcre_exec() and pcre_dfa_exec() when the UTF-8 string check fails, as long
+    as the output vector has at least 2 elements. The offset of the start of
+    the failing character and a reason code are placed in the vector.
+
+6.  When the UTF-8 string check fails for pcre_compile(), the offset that is
+    now returned is for the first byte of the failing character, instead of the
+    last byte inspected. This is an incompatible change, but I hope it is small
+    enough not to be a problem. It makes the returned offset consistent with
+    pcre_exec() and pcre_dfa_exec().
+
+7.  pcretest now gives a text phrase as well as the error number when
+    pcre_exec() or pcre_dfa_exec() fails; if the error is a UTF-8 check
+    failure, the offset and reason code are output.
+
+8.  When \R was used with a maximizing quantifier it failed to skip backwards
+    over a \r\n pair if the subsequent match failed. Instead, it just skipped
+    back over a single character (\n). This seems wrong (because it treated the
+    two characters as a single entity when going forwards), conflicts with the
+    documentation that \R is equivalent to (?>\r\n|\n|...etc), and makes the
+    behaviour of \R* different to (\R)*, which also seems wrong. The behaviour
+    has been changed.
+
+9.  Some internal refactoring has changed the processing so that the handling
+    of the PCRE_CASELESS and PCRE_MULTILINE options is done entirely at compile
+    time (the PCRE_DOTALL option was changed this way some time ago: version
+    7.7 change 16). This has made it possible to abolish the OP_OPT op code,
+    which was always a bit of a fudge. It also means that there is one less
+    argument for the match() function, which reduces its stack requirements
+    slightly. This change also fixes an incompatibility with Perl: the pattern
+    (?i:([^b]))(?1) should not match "ab", but previously PCRE gave a match.
+
+10. More internal refactoring has drastically reduced the number of recursive
+    calls to match() for possessively repeated groups such as (abc)++ when
+    using pcre_exec().
+
+11. While implementing 10, a number of bugs in the handling of groups were
+    discovered and fixed:
+
+    (?<=(a)+) was not diagnosed as invalid (non-fixed-length lookbehind).
+    (a|)*(?1) gave a compile-time internal error.
+    ((a|)+)+  did not notice that the outer group could match an empty string.
+    (^a|^)+   was not marked as anchored.
+    (.*a|.*)+ was not marked as matching at start or after a newline.
+
+12. Yet more internal refactoring has removed another argument from the match()
+    function. Special calls to this function are now indicated by setting a
+    value in a variable in the "match data" data block.
+
+13. Be more explicit in pcre_study() instead of relying on "default" for
+    opcodes that mean there is no starting character; this means that when new
+    ones are added and accidentally left out of pcre_study(), testing should
+    pick them up.
+
+14. The -s option of pcretest has been documented for ages as being an old
+    synonym of -m (show memory usage). I have changed it to mean "force study
+    for every regex", that is, assume /S for every regex. This is similar to -i
+    and -d etc. It's slightly incompatible, but I'm hoping nobody is still
+    using it. It makes it easier to run collections of tests with and without
+    study enabled, and thereby test pcre_study() more easily. All the standard
+    tests are now run with and without -s (but some patterns can be marked as
+    "never study" - see 20 below).
+
+15. When (*ACCEPT) was used in a subpattern that was called recursively, the
+    restoration of the capturing data to the outer values was not happening
+    correctly.
+
+16. If a recursively called subpattern ended with (*ACCEPT) and matched an
+    empty string, and PCRE_NOTEMPTY was set, pcre_exec() thought the whole
+    pattern had matched an empty string, and so incorrectly returned a no
+    match.
+
+17. There was optimizing code for the last branch of non-capturing parentheses,
+    and also for the obeyed branch of a conditional subexpression, which used
+    tail recursion to cut down on stack usage. Unfortunately, now that there is
+    the possibility of (*THEN) occurring in these branches, tail recursion is
+    no longer possible because the return has to be checked for (*THEN). These
+    two optimizations have therefore been removed. [But see 8.20/11 above.]
+
+18. If a pattern containing \R was studied, it was assumed that \R always
+    matched two bytes, thus causing the minimum subject length to be
+    incorrectly computed because \R can also match just one byte.
+
+19. If a pattern containing (*ACCEPT) was studied, the minimum subject length
+    was incorrectly computed.
+
+20. If /S is present twice on a test pattern in pcretest input, it now
+    *disables* studying, thereby overriding the use of -s on the command line
+    (see 14 above). This is necessary for one or two tests to keep the output
+    identical in both cases.
+
+21. When (*ACCEPT) was used in an assertion that matched an empty string and
+    PCRE_NOTEMPTY was set, PCRE applied the non-empty test to the assertion.
+
+22. When an atomic group that contained a capturing parenthesis was
+    successfully matched, but the branch in which it appeared failed, the
+    capturing was not being forgotten if a higher numbered group was later
+    captured. For example, /(?>(a))b|(a)c/ when matching "ac" set capturing
+    group 1 to "a", when in fact it should be unset. This applied to multi-
+    branched capturing and non-capturing groups, repeated or not, and also to
+    positive assertions (capturing in negative assertions does not happen
+    in PCRE) and also to nested atomic groups.
+
+23. Add the ++ qualifier feature to pcretest, to show the remainder of the
+    subject after a captured substring, to make it easier to tell which of a
+    number of identical substrings has been captured.
+
+24. The way atomic groups are processed by pcre_exec() has been changed so that
+    if they are repeated, backtracking one repetition now resets captured
+    values correctly. For example, if ((?>(a+)b)+aabab) is matched against
+    "aaaabaaabaabab" the value of captured group 2 is now correctly recorded as
+    "aaa". Previously, it would have been "a". As part of this code
+    refactoring, the way recursive calls are handled has also been changed.
+
+25. If an assertion condition captured any substrings, they were not passed
+    back unless some other capturing happened later. For example, if
+    (?(?=(a))a) was matched against "a", no capturing was returned.
+
+26. When studying a pattern that contained subroutine calls or assertions,
+    the code for finding the minimum length of a possible match was handling
+    direct recursions such as (xxx(?1)|yyy) but not mutual recursions (where
+    group 1 called group 2 while simultaneously a separate group 2 called group
+    1). A stack overflow occurred in this case. I have fixed this by limiting
+    the recursion depth to 10.
+
+27. Updated RunTest.bat in the distribution to the version supplied by Tom
+    Fortmann. This supports explicit test numbers on the command line, and has
+    argument validation and error reporting.
+
+28. An instance of \X with an unlimited repeat could fail if at any point the
+    first character it looked at was a mark character.
+
+29. Some minor code refactoring concerning Unicode properties and scripts
+    should reduce the stack requirement of match() slightly.
+
+30. Added the '=' option to pcretest to check the setting of unused capturing
+    slots at the end of the pattern, which are documented as being -1, but are
+    not included in the return count.
+
+31. If \k was not followed by a braced, angle-bracketed, or quoted name, PCRE
+    compiled something random. Now it gives a compile-time error (as does
+    Perl).
+
+32. A *MARK encountered during the processing of a positive assertion is now
+    recorded and passed back (compatible with Perl).
+
+33. If --only-matching or --colour was set on a pcregrep call whose pattern
+    had alternative anchored branches, the search for a second match in a line
+    was done as if at the line start. Thus, for example, /^01|^02/ incorrectly
+    matched the line "0102" twice. The same bug affected patterns that started
+    with a backwards assertion. For example /\b01|\b02/ also matched "0102"
+    twice.
+
+34. Previously, PCRE did not allow quantification of assertions. However, Perl
+    does, and because of capturing effects, quantifying parenthesized
+    assertions may at times be useful. Quantifiers are now allowed for
+    parenthesized assertions.
+
+35. A minor code tidy in pcre_compile() when checking options for \R usage.
+
+36. \g was being checked for fancy things in a character class, when it should
+    just be a literal "g".
+
+37. PCRE was rejecting [:a[:digit:]] whereas Perl was not. It seems that the
+    appearance of a nested POSIX class supersedes an apparent external class.
+    For example, [:a[:digit:]b:] matches "a", "b", ":", or a digit. Also,
+    unescaped square brackets may also appear as part of class names. For
+    example, [:a[:abc]b:] gives unknown class "[:abc]b:]". PCRE now behaves
+    more like Perl. (But see 8.20/1 above.)
+
+38. PCRE was giving an error for \N with a braced quantifier such as {1,} (this
+    was because it thought it was \N{name}, which is not supported).
+
+39. Add minix to OS list not supporting the -S option in pcretest.
+
+40. PCRE tries to detect cases of infinite recursion at compile time, but it
+    cannot analyze patterns in sufficient detail to catch mutual recursions
+    such as ((?1))((?2)). There is now a runtime test that gives an error if a
+    subgroup is called recursively as a subpattern for a second time at the
+    same position in the subject string. In previous releases this might have
+    been caught by the recursion limit, or it might have run out of stack.
+
+41. A pattern such as /(?(R)a+|(?R)b)/ is quite safe, as the recursion can
+    happen only once. PCRE was, however incorrectly giving a compile time error
+    "recursive call could loop indefinitely" because it cannot analyze the
+    pattern in sufficient detail. The compile time test no longer happens when
+    PCRE is compiling a conditional subpattern, but actual runaway loops are
+    now caught at runtime (see 40 above).
+
+42. It seems that Perl allows any characters other than a closing parenthesis
+    to be part of the NAME in (*MARK:NAME) and other backtracking verbs. PCRE
+    has been changed to be the same.
+
+43. Updated configure.ac to put in more quoting round AC_LANG_PROGRAM etc. so
+    as not to get warnings when autogen.sh is called. Also changed
+    AC_PROG_LIBTOOL (deprecated) to LT_INIT (the current macro).
+
+44. To help people who use pcregrep to scan files containing exceedingly long
+    lines, the following changes have been made:
+
+    (a) The default value of the buffer size parameter has been increased from
+        8K to 20K. (The actual buffer used is three times this size.)
+
+    (b) The default can be changed by ./configure --with-pcregrep-bufsize when
+        PCRE is built.
+
+    (c) A --buffer-size=n option has been added to pcregrep, to allow the size
+        to be set at run time.
+
+    (d) Numerical values in pcregrep options can be followed by K or M, for
+        example --buffer-size=50K.
+
+    (e) If a line being scanned overflows pcregrep's buffer, an error is now
+        given and the return code is set to 2.
+
+45. Add a pointer to the latest mark to the callout data block.
+
+46. The pattern /.(*F)/, when applied to "abc" with PCRE_PARTIAL_HARD, gave a
+    partial match of an empty string instead of no match. This was specific to
+    the use of ".".
+
+47. The pattern /f.*/8s, when applied to "for" with PCRE_PARTIAL_HARD, gave a
+    complete match instead of a partial match. This bug was dependent on both
+    the PCRE_UTF8 and PCRE_DOTALL options being set.
+
+48. For a pattern such as /\babc|\bdef/ pcre_study() was failing to set up the
+    starting byte set, because \b was not being ignored.
+
+
+Version 8.12 15-Jan-2011
+------------------------
+
+1.  Fixed some typos in the markup of the man pages, and wrote a script that
+    checks for such things as part of the documentation building process.
+
+2.  On a big-endian 64-bit system, pcregrep did not correctly process the
+    --match-limit and --recursion-limit options (added for 8.11). In
+    particular, this made one of the standard tests fail. (The integer value
+    went into the wrong half of a long int.)
+
+3.  If the --colour option was given to pcregrep with -v (invert match), it
+    did strange things, either producing crazy output, or crashing. It should,
+    of course, ignore a request for colour when reporting lines that do not
+    match.
+
+4.  Another pcregrep bug caused similar problems if --colour was specified with
+    -M (multiline) and the pattern match finished with a line ending.
+
+5.  In pcregrep, when a pattern that ended with a literal newline sequence was
+    matched in multiline mode, the following line was shown as part of the
+    match. This seems wrong, so I have changed it.
+
+6.  Another pcregrep bug in multiline mode, when --colour was specified, caused
+    the check for further matches in the same line (so they could be coloured)
+    to overrun the end of the current line. If another match was found, it was
+    incorrectly shown (and then shown again when found in the next line).
+
+7.  If pcregrep was compiled under Windows, there was a reference to the
+    function pcregrep_exit() before it was defined. I am assuming this was
+    the cause of the "error C2371: 'pcregrep_exit' : redefinition;" that was
+    reported by a user. I've moved the definition above the reference.
+
+
+Version 8.11 10-Dec-2010
+------------------------
+
+1.  (*THEN) was not working properly if there were untried alternatives prior
+    to it in the current branch. For example, in ((a|b)(*THEN)(*F)|c..) it
+    backtracked to try for "b" instead of moving to the next alternative branch
+    at the same level (in this case, to look for "c"). The Perl documentation
+    is clear that when (*THEN) is backtracked onto, it goes to the "next
+    alternative in the innermost enclosing group".
+
+2.  (*COMMIT) was not overriding (*THEN), as it does in Perl. In a pattern
+    such as   (A(*COMMIT)B(*THEN)C|D)  any failure after matching A should
+    result in overall failure. Similarly, (*COMMIT) now overrides (*PRUNE) and
+    (*SKIP), (*SKIP) overrides (*PRUNE) and (*THEN), and (*PRUNE) overrides
+    (*THEN).
+
+3.  If \s appeared in a character class, it removed the VT character from
+    the class, even if it had been included by some previous item, for example
+    in [\x00-\xff\s]. (This was a bug related to the fact that VT is not part
+    of \s, but is part of the POSIX "space" class.)
+
+4.  A partial match never returns an empty string (because you can always
+    match an empty string at the end of the subject); however the checking for
+    an empty string was starting at the "start of match" point. This has been
+    changed to the "earliest inspected character" point, because the returned
+    data for a partial match starts at this character. This means that, for
+    example, /(?<=abc)def/ gives a partial match for the subject "abc"
+    (previously it gave "no match").
+
+5.  Changes have been made to the way PCRE_PARTIAL_HARD affects the matching
+    of $, \z, \Z, \b, and \B. If the match point is at the end of the string,
+    previously a full match would be given. However, setting PCRE_PARTIAL_HARD
+    has an implication that the given string is incomplete (because a partial
+    match is preferred over a full match). For this reason, these items now
+    give a partial match in this situation. [Aside: previously, the one case
+    /t\b/ matched against "cat" with PCRE_PARTIAL_HARD set did return a partial
+    match rather than a full match, which was wrong by the old rules, but is
+    now correct.]
+
+6.  There was a bug in the handling of #-introduced comments, recognized when
+    PCRE_EXTENDED is set, when PCRE_NEWLINE_ANY and PCRE_UTF8 were also set.
+    If a UTF-8 multi-byte character included the byte 0x85 (e.g. +U0445, whose
+    UTF-8 encoding is 0xd1,0x85), this was misinterpreted as a newline when
+    scanning for the end of the comment. (*Character* 0x85 is an "any" newline,
+    but *byte* 0x85 is not, in UTF-8 mode). This bug was present in several
+    places in pcre_compile().
+
+7.  Related to (6) above, when pcre_compile() was skipping #-introduced
+    comments when looking ahead for named forward references to subpatterns,
+    the only newline sequence it recognized was NL. It now handles newlines
+    according to the set newline convention.
+
+8.  SunOS4 doesn't have strerror() or strtoul(); pcregrep dealt with the
+    former, but used strtoul(), whereas pcretest avoided strtoul() but did not
+    cater for a lack of strerror(). These oversights have been fixed.
+
+9.  Added --match-limit and --recursion-limit to pcregrep.
+
+10. Added two casts needed to build with Visual Studio when NO_RECURSE is set.
+
+11. When the -o option was used, pcregrep was setting a return code of 1, even
+    when matches were found, and --line-buffered was not being honoured.
+
+12. Added an optional parentheses number to the -o and --only-matching options
+    of pcregrep.
+
+13. Imitating Perl's /g action for multiple matches is tricky when the pattern
+    can match an empty string. The code to do it in pcretest and pcredemo
+    needed fixing:
+
+    (a) When the newline convention was "crlf", pcretest got it wrong, skipping
+        only one byte after an empty string match just before CRLF (this case
+        just got forgotten; "any" and "anycrlf" were OK).
+
+    (b) The pcretest code also had a bug, causing it to loop forever in UTF-8
+        mode when an empty string match preceded an ASCII character followed by
+        a non-ASCII character. (The code for advancing by one character rather
+        than one byte was nonsense.)
+
+    (c) The pcredemo.c sample program did not have any code at all to handle
+        the cases when CRLF is a valid newline sequence.
+
+14. Neither pcre_exec() nor pcre_dfa_exec() was checking that the value given
+    as a starting offset was within the subject string. There is now a new
+    error, PCRE_ERROR_BADOFFSET, which is returned if the starting offset is
+    negative or greater than the length of the string. In order to test this,
+    pcretest is extended to allow the setting of negative starting offsets.
+
+15. In both pcre_exec() and pcre_dfa_exec() the code for checking that the
+    starting offset points to the beginning of a UTF-8 character was
+    unnecessarily clumsy. I tidied it up.
+
+16. Added PCRE_ERROR_SHORTUTF8 to make it possible to distinguish between a
+    bad UTF-8 sequence and one that is incomplete when using PCRE_PARTIAL_HARD.
+
+17. Nobody had reported that the --include_dir option, which was added in
+    release 7.7 should have been called --include-dir (hyphen, not underscore)
+    for compatibility with GNU grep. I have changed it to --include-dir, but
+    left --include_dir as an undocumented synonym, and the same for
+    --exclude-dir, though that is not available in GNU grep, at least as of
+    release 2.5.4.
+
+18. At a user's suggestion, the macros GETCHAR and friends (which pick up UTF-8
+    characters from a string of bytes) have been redefined so as not to use
+    loops, in order to improve performance in some environments. At the same
+    time, I abstracted some of the common code into auxiliary macros to save
+    repetition (this should not affect the compiled code).
+
+19. If \c was followed by a multibyte UTF-8 character, bad things happened. A
+    compile-time error is now given if \c is not followed by an ASCII
+    character, that is, a byte less than 128. (In EBCDIC mode, the code is
+    different, and any byte value is allowed.)
+
+20. Recognize (*NO_START_OPT) at the start of a pattern to set the PCRE_NO_
+    START_OPTIMIZE option, which is now allowed at compile time - but just
+    passed through to pcre_exec() or pcre_dfa_exec(). This makes it available
+    to pcregrep and other applications that have no direct access to PCRE
+    options. The new /Y option in pcretest sets this option when calling
+    pcre_compile().
+
+21. Change 18 of release 8.01 broke the use of named subpatterns for recursive
+    back references. Groups containing recursive back references were forced to
+    be atomic by that change, but in the case of named groups, the amount of
+    memory required was incorrectly computed, leading to "Failed: internal
+    error: code overflow". This has been fixed.
+
+22. Some patches to pcre_stringpiece.h, pcre_stringpiece_unittest.cc, and
+    pcretest.c, to avoid build problems in some Borland environments.
+
+
+Version 8.10 25-Jun-2010
+------------------------
+
+1.  Added support for (*MARK:ARG) and for ARG additions to PRUNE, SKIP, and
+    THEN.
+
+2.  (*ACCEPT) was not working when inside an atomic group.
+
+3.  Inside a character class, \B is treated as a literal by default, but
+    faulted if PCRE_EXTRA is set. This mimics Perl's behaviour (the -w option
+    causes the error). The code is unchanged, but I tidied the documentation.
+
+4.  Inside a character class, PCRE always treated \R and \X as literals,
+    whereas Perl faults them if its -w option is set. I have changed PCRE so
+    that it faults them when PCRE_EXTRA is set.
+
+5.  Added support for \N, which always matches any character other than
+    newline. (It is the same as "." when PCRE_DOTALL is not set.)
+
+6.  When compiling pcregrep with newer versions of gcc which may have
+    FORTIFY_SOURCE set, several warnings "ignoring return value of 'fwrite',
+    declared with attribute warn_unused_result" were given. Just casting the
+    result to (void) does not stop the warnings; a more elaborate fudge is
+    needed. I've used a macro to implement this.
+
+7.  Minor change to pcretest.c to avoid a compiler warning.
+
+8.  Added four artifical Unicode properties to help with an option to make
+    \s etc use properties (see next item). The new properties are: Xan
+    (alphanumeric), Xsp (Perl space), Xps (POSIX space), and Xwd (word).
+
+9.  Added PCRE_UCP to make \b, \d, \s, \w, and certain POSIX character classes
+    use Unicode properties. (*UCP) at the start of a pattern can be used to set
+    this option. Modified pcretest to add /W to test this facility. Added
+    REG_UCP to make it available via the POSIX interface.
+
+10. Added --line-buffered to pcregrep.
+
+11. In UTF-8 mode, if a pattern that was compiled with PCRE_CASELESS was
+    studied, and the match started with a letter with a code point greater than
+    127 whose first byte was different to the first byte of the other case of
+    the letter, the other case of this starting letter was not recognized
+    (#976).
+
+12. If a pattern that was studied started with a repeated Unicode property
+    test, for example, \p{Nd}+, there was the theoretical possibility of
+    setting up an incorrect bitmap of starting bytes, but fortunately it could
+    not have actually happened in practice until change 8 above was made (it
+    added property types that matched character-matching opcodes).
+
+13. pcre_study() now recognizes \h, \v, and \R when constructing a bit map of
+    possible starting bytes for non-anchored patterns.
+
+14. Extended the "auto-possessify" feature of pcre_compile(). It now recognizes
+    \R, and also a number of cases that involve Unicode properties, both
+    explicit and implicit when PCRE_UCP is set.
+
+15. If a repeated Unicode property match (e.g. \p{Lu}*) was used with non-UTF-8
+    input, it could crash or give wrong results if characters with values
+    greater than 0xc0 were present in the subject string. (Detail: it assumed
+    UTF-8 input when processing these items.)
+
+16. Added a lot of (int) casts to avoid compiler warnings in systems where
+    size_t is 64-bit (#991).
+
+17. Added a check for running out of memory when PCRE is compiled with
+    --disable-stack-for-recursion (#990).
+
+18. If the last data line in a file for pcretest does not have a newline on
+    the end, a newline was missing in the output.
+
+19. The default pcre_chartables.c file recognizes only ASCII characters (values
+    less than 128) in its various bitmaps. However, there is a facility for
+    generating tables according to the current locale when PCRE is compiled. It
+    turns out that in some environments, 0x85 and 0xa0, which are Unicode space
+    characters, are recognized by isspace() and therefore were getting set in
+    these tables, and indeed these tables seem to approximate to ISO 8859. This
+    caused a problem in UTF-8 mode when pcre_study() was used to create a list
+    of bytes that can start a match. For \s, it was including 0x85 and 0xa0,
+    which of course cannot start UTF-8 characters. I have changed the code so
+    that only real ASCII characters (less than 128) and the correct starting
+    bytes for UTF-8 encodings are set for characters greater than 127 when in
+    UTF-8 mode. (When PCRE_UCP is set - see 9 above - the code is different
+    altogether.)
+
+20. Added the /T option to pcretest so as to be able to run tests with non-
+    standard character tables, thus making it possible to include the tests
+    used for 19 above in the standard set of tests.
+
+21. A pattern such as (?&t)(?#()(?(DEFINE)(?<t>a)) which has a forward
+    reference to a subpattern the other side of a comment that contains an
+    opening parenthesis caused either an internal compiling error, or a
+    reference to the wrong subpattern.
+
+
+Version 8.02 19-Mar-2010
+------------------------
+
+1.  The Unicode data tables have been updated to Unicode 5.2.0.
+
+2.  Added the option --libs-cpp to pcre-config, but only when C++ support is
+    configured.
+
+3.  Updated the licensing terms in the pcregexp.pas file, as agreed with the
+    original author of that file, following a query about its status.
+
+4.  On systems that do not have stdint.h (e.g. Solaris), check for and include
+    inttypes.h instead. This fixes a bug that was introduced by change 8.01/8.
+
+5.  A pattern such as (?&t)*+(?(DEFINE)(?<t>.)) which has a possessive
+    quantifier applied to a forward-referencing subroutine call, could compile
+    incorrect code or give the error "internal error: previously-checked
+    referenced subpattern not found".
+
+6.  Both MS Visual Studio and Symbian OS have problems with initializing
+    variables to point to external functions. For these systems, therefore,
+    pcre_malloc etc. are now initialized to local functions that call the
+    relevant global functions.
+
+7.  There were two entries missing in the vectors called coptable and poptable
+    in pcre_dfa_exec.c. This could lead to memory accesses outsize the vectors.
+    I've fixed the data, and added a kludgy way of testing at compile time that
+    the lengths are correct (equal to the number of opcodes).
+
+8.  Following on from 7, I added a similar kludge to check the length of the
+    eint vector in pcreposix.c.
+
+9.  Error texts for pcre_compile() are held as one long string to avoid too
+    much relocation at load time. To find a text, the string is searched,
+    counting zeros. There was no check for running off the end of the string,
+    which could happen if a new error number was added without updating the
+    string.
+
+10. \K gave a compile-time error if it appeared in a lookbehind assersion.
+
+11. \K was not working if it appeared in an atomic group or in a group that
+    was called as a "subroutine", or in an assertion. Perl 5.11 documents that
+    \K is "not well defined" if used in an assertion. PCRE now accepts it if
+    the assertion is positive, but not if it is negative.
+
+12. Change 11 fortuitously reduced the size of the stack frame used in the
+    "match()" function of pcre_exec.c by one pointer. Forthcoming
+    implementation of support for (*MARK) will need an extra pointer on the
+    stack; I have reserved it now, so that the stack frame size does not
+    decrease.
+
+13. A pattern such as (?P<L1>(?P<L2>0)|(?P>L2)(?P>L1)) in which the only other
+    item in branch that calls a recursion is a subroutine call - as in the
+    second branch in the above example - was incorrectly given the compile-
+    time error "recursive call could loop indefinitely" because pcre_compile()
+    was not correctly checking the subroutine for matching a non-empty string.
+
+14. The checks for overrunning compiling workspace could trigger after an
+    overrun had occurred. This is a "should never occur" error, but it can be
+    triggered by pathological patterns such as hundreds of nested parentheses.
+    The checks now trigger 100 bytes before the end of the workspace.
+
+15. Fix typo in configure.ac: "srtoq" should be "strtoq".
+
+
+Version 8.01 19-Jan-2010
+------------------------
+
+1.  If a pattern contained a conditional subpattern with only one branch (in
+    particular, this includes all (*DEFINE) patterns), a call to pcre_study()
+    computed the wrong minimum data length (which is of course zero for such
+    subpatterns). This could cause incorrect "no match" results.
+
+2.  For patterns such as (?i)a(?-i)b|c where an option setting at the start of
+    the pattern is reset in the first branch, pcre_compile() failed with
+    "internal error: code overflow at offset...". This happened only when
+    the reset was to the original external option setting. (An optimization
+    abstracts leading options settings into an external setting, which was the
+    cause of this.)
+
+3.  A pattern such as ^(?!a(*SKIP)b) where a negative assertion contained one
+    of the verbs SKIP, PRUNE, or COMMIT, did not work correctly. When the
+    assertion pattern did not match (meaning that the assertion was true), it
+    was incorrectly treated as false if the SKIP had been reached during the
+    matching. This also applied to assertions used as conditions.
+
+4.  If an item that is not supported by pcre_dfa_exec() was encountered in an
+    assertion subpattern, including such a pattern used as a condition,
+    unpredictable results occurred, instead of the error return
+    PCRE_ERROR_DFA_UITEM.
+
+5.  The C++ GlobalReplace function was not working like Perl for the special
+    situation when an empty string is matched. It now does the fancy magic
+    stuff that is necessary.
+
+6.  In pcre_internal.h, obsolete includes to setjmp.h and stdarg.h have been
+    removed. (These were left over from very, very early versions of PCRE.)
+
+7.  Some cosmetic changes to the code to make life easier when compiling it
+    as part of something else:
+
+    (a) Change DEBUG to PCRE_DEBUG.
+
+    (b) In pcre_compile(), rename the member of the "branch_chain" structure
+        called "current" as "current_branch", to prevent a collision with the
+        Linux macro when compiled as a kernel module.
+
+    (c) In pcre_study(), rename the function set_bit() as set_table_bit(), to
+        prevent a collision with the Linux macro when compiled as a kernel
+        module.
+
+8.  In pcre_compile() there are some checks for integer overflows that used to
+    cast potentially large values to (double). This has been changed to that
+    when building, a check for int64_t is made, and if it is found, it is used
+    instead, thus avoiding the use of floating point arithmetic. (There is no
+    other use of FP in PCRE.) If int64_t is not found, the fallback is to
+    double.
+
+9.  Added two casts to avoid signed/unsigned warnings from VS Studio Express
+    2005 (difference between two addresses compared to an unsigned value).
+
+10. Change the standard AC_CHECK_LIB test for libbz2 in configure.ac to a
+    custom one, because of the following reported problem in Windows:
+
+      - libbz2 uses the Pascal calling convention (WINAPI) for the functions
+          under Win32.
+      - The standard autoconf AC_CHECK_LIB fails to include "bzlib.h",
+          therefore missing the function definition.
+      - The compiler thus generates a "C" signature for the test function.
+      - The linker fails to find the "C" function.
+      - PCRE fails to configure if asked to do so against libbz2.
+
+11. When running libtoolize from libtool-2.2.6b as part of autogen.sh, these
+    messages were output:
+
+      Consider adding `AC_CONFIG_MACRO_DIR([m4])' to configure.ac and
+      rerunning libtoolize, to keep the correct libtool macros in-tree.
+      Consider adding `-I m4' to ACLOCAL_AMFLAGS in Makefile.am.
+
+    I have done both of these things.
+
+12. Although pcre_dfa_exec() does not use nearly as much stack as pcre_exec()
+    most of the time, it *can* run out if it is given a pattern that contains a
+    runaway infinite recursion. I updated the discussion in the pcrestack man
+    page.
+
+13. Now that we have gone to the x.xx style of version numbers, the minor
+    version may start with zero. Using 08 or 09 is a bad idea because users
+    might check the value of PCRE_MINOR in their code, and 08 or 09 may be
+    interpreted as invalid octal numbers. I've updated the previous comment in
+    configure.ac, and also added a check that gives an error if 08 or 09 are
+    used.
+
+14. Change 8.00/11 was not quite complete: code had been accidentally omitted,
+    causing partial matching to fail when the end of the subject matched \W
+    in a UTF-8 pattern where \W was quantified with a minimum of 3.
+
+15. There were some discrepancies between the declarations in pcre_internal.h
+    of _pcre_is_newline(), _pcre_was_newline(), and _pcre_valid_utf8() and
+    their definitions. The declarations used "const uschar *" and the
+    definitions used USPTR. Even though USPTR is normally defined as "const
+    unsigned char *" (and uschar is typedeffed as "unsigned char"), it was
+    reported that: "This difference in casting confuses some C++ compilers, for
+    example, SunCC recognizes above declarations as different functions and
+    generates broken code for hbpcre." I have changed the declarations to use
+    USPTR.
+
+16. GNU libtool is named differently on some systems. The autogen.sh script now
+    tries several variants such as glibtoolize (MacOSX) and libtoolize1x
+    (FreeBSD).
+
+17. Applied Craig's patch that fixes an HP aCC compile error in pcre 8.00
+    (strtoXX undefined when compiling pcrecpp.cc). The patch contains this
+    comment: "Figure out how to create a longlong from a string: strtoll and
+    equivalent. It's not enough to call AC_CHECK_FUNCS: hpux has a strtoll, for
+    instance, but it only takes 2 args instead of 3!"
+
+18. A subtle bug concerned with back references has been fixed by a change of
+    specification, with a corresponding code fix. A pattern such as
+    ^(xa|=?\1a)+$ which contains a back reference inside the group to which it
+    refers, was giving matches when it shouldn't. For example, xa=xaaa would
+    match that pattern. Interestingly, Perl (at least up to 5.11.3) has the
+    same bug. Such groups have to be quantified to be useful, or contained
+    inside another quantified group. (If there's no repetition, the reference
+    can never match.) The problem arises because, having left the group and
+    moved on to the rest of the pattern, a later failure that backtracks into
+    the group uses the captured value from the final iteration of the group
+    rather than the correct earlier one. I have fixed this in PCRE by forcing
+    any group that contains a reference to itself to be an atomic group; that
+    is, there cannot be any backtracking into it once it has completed. This is
+    similar to recursive and subroutine calls.
+
+
+Version 8.00 19-Oct-09
+----------------------
+
+1.  The table for translating pcre_compile() error codes into POSIX error codes
+    was out-of-date, and there was no check on the pcre_compile() error code
+    being within the table. This could lead to an OK return being given in
+    error.
+
+2.  Changed the call to open a subject file in pcregrep from fopen(pathname,
+    "r") to fopen(pathname, "rb"), which fixed a problem with some of the tests
+    in a Windows environment.
+
+3.  The pcregrep --count option prints the count for each file even when it is
+    zero, as does GNU grep. However, pcregrep was also printing all files when
+    --files-with-matches was added. Now, when both options are given, it prints
+    counts only for those files that have at least one match. (GNU grep just
+    prints the file name in this circumstance, but including the count seems
+    more useful - otherwise, why use --count?) Also ensured that the
+    combination -clh just lists non-zero counts, with no names.
+
+4.  The long form of the pcregrep -F option was incorrectly implemented as
+    --fixed_strings instead of --fixed-strings. This is an incompatible change,
+    but it seems right to fix it, and I didn't think it was worth preserving
+    the old behaviour.
+
+5.  The command line items --regex=pattern and --regexp=pattern were not
+    recognized by pcregrep, which required --regex pattern or --regexp pattern
+    (with a space rather than an '='). The man page documented the '=' forms,
+    which are compatible with GNU grep; these now work.
+
+6.  No libpcreposix.pc file was created for pkg-config; there was just
+    libpcre.pc and libpcrecpp.pc. The omission has been rectified.
+
+7.  Added #ifndef SUPPORT_UCP into the pcre_ucd.c module, to reduce its size
+    when UCP support is not needed, by modifying the Python script that
+    generates it from Unicode data files. This should not matter if the module
+    is correctly used as a library, but I received one complaint about 50K of
+    unwanted data. My guess is that the person linked everything into his
+    program rather than using a library. Anyway, it does no harm.
+
+8.  A pattern such as /\x{123}{2,2}+/8 was incorrectly compiled; the trigger
+    was a minimum greater than 1 for a wide character in a possessive
+    repetition. The same bug could also affect patterns like /(\x{ff}{0,2})*/8
+    which had an unlimited repeat of a nested, fixed maximum repeat of a wide
+    character. Chaos in the form of incorrect output or a compiling loop could
+    result.
+
+9.  The restrictions on what a pattern can contain when partial matching is
+    requested for pcre_exec() have been removed. All patterns can now be
+    partially matched by this function. In addition, if there are at least two
+    slots in the offset vector, the offset of the earliest inspected character
+    for the match and the offset of the end of the subject are set in them when
+    PCRE_ERROR_PARTIAL is returned.
+
+10. Partial matching has been split into two forms: PCRE_PARTIAL_SOFT, which is
+    synonymous with PCRE_PARTIAL, for backwards compatibility, and
+    PCRE_PARTIAL_HARD, which causes a partial match to supersede a full match,
+    and may be more useful for multi-segment matching.
+
+11. Partial matching with pcre_exec() is now more intuitive. A partial match
+    used to be given if ever the end of the subject was reached; now it is
+    given only if matching could not proceed because another character was
+    needed. This makes a difference in some odd cases such as Z(*FAIL) with the
+    string "Z", which now yields "no match" instead of "partial match". In the
+    case of pcre_dfa_exec(), "no match" is given if every matching path for the
+    final character ended with (*FAIL).
+
+12. Restarting a match using pcre_dfa_exec() after a partial match did not work
+    if the pattern had a "must contain" character that was already found in the
+    earlier partial match, unless partial matching was again requested. For
+    example, with the pattern /dog.(body)?/, the "must contain" character is
+    "g". If the first part-match was for the string "dog", restarting with
+    "sbody" failed. This bug has been fixed.
+
+13. The string returned by pcre_dfa_exec() after a partial match has been
+    changed so that it starts at the first inspected character rather than the
+    first character of the match. This makes a difference only if the pattern
+    starts with a lookbehind assertion or \b or \B (\K is not supported by
+    pcre_dfa_exec()). It's an incompatible change, but it makes the two
+    matching functions compatible, and I think it's the right thing to do.
+
+14. Added a pcredemo man page, created automatically from the pcredemo.c file,
+    so that the demonstration program is easily available in environments where
+    PCRE has not been installed from source.
+
+15. Arranged to add -DPCRE_STATIC to cflags in libpcre.pc, libpcreposix.cp,
+    libpcrecpp.pc and pcre-config when PCRE is not compiled as a shared
+    library.
+
+16. Added REG_UNGREEDY to the pcreposix interface, at the request of a user.
+    It maps to PCRE_UNGREEDY. It is not, of course, POSIX-compatible, but it
+    is not the first non-POSIX option to be added. Clearly some people find
+    these options useful.
+
+17. If a caller to the POSIX matching function regexec() passes a non-zero
+    value for nmatch with a NULL value for pmatch, the value of
+    nmatch is forced to zero.
+
+18. RunGrepTest did not have a test for the availability of the -u option of
+    the diff command, as RunTest does. It now checks in the same way as
+    RunTest, and also checks for the -b option.
+
+19. If an odd number of negated classes containing just a single character
+    interposed, within parentheses, between a forward reference to a named
+    subpattern and the definition of the subpattern, compilation crashed with
+    an internal error, complaining that it could not find the referenced
+    subpattern. An example of a crashing pattern is /(?&A)(([^m])(?<A>))/.
+    [The bug was that it was starting one character too far in when skipping
+    over the character class, thus treating the ] as data rather than
+    terminating the class. This meant it could skip too much.]
+
+20. Added PCRE_NOTEMPTY_ATSTART in order to be able to correctly implement the
+    /g option in pcretest when the pattern contains \K, which makes it possible
+    to have an empty string match not at the start, even when the pattern is
+    anchored. Updated pcretest and pcredemo to use this option.
+
+21. If the maximum number of capturing subpatterns in a recursion was greater
+    than the maximum at the outer level, the higher number was returned, but
+    with unset values at the outer level. The correct (outer level) value is
+    now given.
+
+22. If (*ACCEPT) appeared inside capturing parentheses, previous releases of
+    PCRE did not set those parentheses (unlike Perl). I have now found a way to
+    make it do so. The string so far is captured, making this feature
+    compatible with Perl.
+
+23. The tests have been re-organized, adding tests 11 and 12, to make it
+    possible to check the Perl 5.10 features against Perl 5.10.
+
+24. Perl 5.10 allows subroutine calls in lookbehinds, as long as the subroutine
+    pattern matches a fixed length string. PCRE did not allow this; now it
+    does. Neither allows recursion.
+
+25. I finally figured out how to implement a request to provide the minimum
+    length of subject string that was needed in order to match a given pattern.
+    (It was back references and recursion that I had previously got hung up
+    on.) This code has now been added to pcre_study(); it finds a lower bound
+    to the length of subject needed. It is not necessarily the greatest lower
+    bound, but using it to avoid searching strings that are too short does give
+    some useful speed-ups. The value is available to calling programs via
+    pcre_fullinfo().
+
+26. While implementing 25, I discovered to my embarrassment that pcretest had
+    not been passing the result of pcre_study() to pcre_dfa_exec(), so the
+    study optimizations had never been tested with that matching function.
+    Oops. What is worse, even when it was passed study data, there was a bug in
+    pcre_dfa_exec() that meant it never actually used it. Double oops. There
+    were also very few tests of studied patterns with pcre_dfa_exec().
+
+27. If (?| is used to create subpatterns with duplicate numbers, they are now
+    allowed to have the same name, even if PCRE_DUPNAMES is not set. However,
+    on the other side of the coin, they are no longer allowed to have different
+    names, because these cannot be distinguished in PCRE, and this has caused
+    confusion. (This is a difference from Perl.)
+
+28. When duplicate subpattern names are present (necessarily with different
+    numbers, as required by 27 above), and a test is made by name in a
+    conditional pattern, either for a subpattern having been matched, or for
+    recursion in such a pattern, all the associated numbered subpatterns are
+    tested, and the overall condition is true if the condition is true for any
+    one of them. This is the way Perl works, and is also more like the way
+    testing by number works.
+
+
+Version 7.9 11-Apr-09
+---------------------
+
+1.  When building with support for bzlib/zlib (pcregrep) and/or readline
+    (pcretest), all targets were linked against these libraries. This included
+    libpcre, libpcreposix, and libpcrecpp, even though they do not use these
+    libraries. This caused unwanted dependencies to be created. This problem
+    has been fixed, and now only pcregrep is linked with bzlib/zlib and only
+    pcretest is linked with readline.
+
+2.  The "typedef int BOOL" in pcre_internal.h that was included inside the
+    "#ifndef FALSE" condition by an earlier change (probably 7.8/18) has been
+    moved outside it again, because FALSE and TRUE are already defined in AIX,
+    but BOOL is not.
+
+3.  The pcre_config() function was treating the PCRE_MATCH_LIMIT and
+    PCRE_MATCH_LIMIT_RECURSION values as ints, when they should be long ints.
+
+4.  The pcregrep documentation said spaces were inserted as well as colons (or
+    hyphens) following file names and line numbers when outputting matching
+    lines. This is not true; no spaces are inserted. I have also clarified the
+    wording for the --colour (or --color) option.
+
+5.  In pcregrep, when --colour was used with -o, the list of matching strings
+    was not coloured; this is different to GNU grep, so I have changed it to be
+    the same.
+
+6.  When --colo(u)r was used in pcregrep, only the first matching substring in
+    each matching line was coloured. Now it goes on to look for further matches
+    of any of the test patterns, which is the same behaviour as GNU grep.
+
+7.  A pattern that could match an empty string could cause pcregrep to loop; it
+    doesn't make sense to accept an empty string match in pcregrep, so I have
+    locked it out (using PCRE's PCRE_NOTEMPTY option). By experiment, this
+    seems to be how GNU grep behaves. [But see later change 40 for release
+    8.33.]
+
+8.  The pattern (?(?=.*b)b|^) was incorrectly compiled as "match must be at
+    start or after a newline", because the conditional assertion was not being
+    correctly handled. The rule now is that both the assertion and what follows
+    in the first alternative must satisfy the test.
+
+9.  If auto-callout was enabled in a pattern with a conditional group whose
+    condition was an assertion, PCRE could crash during matching, both with
+    pcre_exec() and pcre_dfa_exec().
+
+10. The PCRE_DOLLAR_ENDONLY option was not working when pcre_dfa_exec() was
+    used for matching.
+
+11. Unicode property support in character classes was not working for
+    characters (bytes) greater than 127 when not in UTF-8 mode.
+
+12. Added the -M command line option to pcretest.
+
+14. Added the non-standard REG_NOTEMPTY option to the POSIX interface.
+
+15. Added the PCRE_NO_START_OPTIMIZE match-time option.
+
+16. Added comments and documentation about mis-use of no_arg in the C++
+    wrapper.
+
+17. Implemented support for UTF-8 encoding in EBCDIC environments, a patch
+    from Martin Jerabek that uses macro names for all relevant character and
+    string constants.
+
+18. Added to pcre_internal.h two configuration checks: (a) If both EBCDIC and
+    SUPPORT_UTF8 are set, give an error; (b) If SUPPORT_UCP is set without
+    SUPPORT_UTF8, define SUPPORT_UTF8. The "configure" script handles both of
+    these, but not everybody uses configure.
+
+19. A conditional group that had only one branch was not being correctly
+    recognized as an item that could match an empty string. This meant that an
+    enclosing group might also not be so recognized, causing infinite looping
+    (and probably a segfault) for patterns such as ^"((?(?=[a])[^"])|b)*"$
+    with the subject "ab", where knowledge that the repeated group can match
+    nothing is needed in order to break the loop.
+
+20. If a pattern that was compiled with callouts was matched using pcre_dfa_
+    exec(), but without supplying a callout function, matching went wrong.
+
+21. If PCRE_ERROR_MATCHLIMIT occurred during a recursion, there was a memory
+    leak if the size of the offset vector was greater than 30. When the vector
+    is smaller, the saved offsets during recursion go onto a local stack
+    vector, but for larger vectors malloc() is used. It was failing to free
+    when the recursion yielded PCRE_ERROR_MATCH_LIMIT (or any other "abnormal"
+    error, in fact).
+
+22. There was a missing #ifdef SUPPORT_UTF8 round one of the variables in the
+    heapframe that is used only when UTF-8 support is enabled. This caused no
+    problem, but was untidy.
+
+23. Steven Van Ingelgem's patch to CMakeLists.txt to change the name
+    CMAKE_BINARY_DIR to PROJECT_BINARY_DIR so that it works when PCRE is
+    included within another project.
+
+24. Steven Van Ingelgem's patches to add more options to the CMake support,
+    slightly modified by me:
+
+      (a) PCRE_BUILD_TESTS can be set OFF not to build the tests, including
+          not building pcregrep.
+
+      (b) PCRE_BUILD_PCREGREP can be see OFF not to build pcregrep, but only
+          if PCRE_BUILD_TESTS is also set OFF, because the tests use pcregrep.
+
+25. Forward references, both numeric and by name, in patterns that made use of
+    duplicate group numbers, could behave incorrectly or give incorrect errors,
+    because when scanning forward to find the reference group, PCRE was not
+    taking into account the duplicate group numbers. A pattern such as
+    ^X(?3)(a)(?|(b)|(q))(Y) is an example.
+
+26. Changed a few more instances of "const unsigned char *" to USPTR, making
+    the feature of a custom pointer more persuasive (as requested by a user).
+
+27. Wrapped the definitions of fileno and isatty for Windows, which appear in
+    pcretest.c, inside #ifndefs, because it seems they are sometimes already
+    pre-defined.
+
+28. Added support for (*UTF8) at the start of a pattern.
+
+29. Arrange for flags added by the "release type" setting in CMake to be shown
+    in the configuration summary.
+
+
+Version 7.8 05-Sep-08
+---------------------
+
+1.  Replaced UCP searching code with optimized version as implemented for Ad
+    Muncher (http://www.admuncher.com/) by Peter Kankowski. This uses a two-
+    stage table and inline lookup instead of a function, giving speed ups of 2
+    to 5 times on some simple patterns that I tested. Permission was given to
+    distribute the MultiStage2.py script that generates the tables (it's not in
+    the tarball, but is in the Subversion repository).
+
+2.  Updated the Unicode datatables to Unicode 5.1.0. This adds yet more
+    scripts.
+
+3.  Change 12 for 7.7 introduced a bug in pcre_study() when a pattern contained
+    a group with a zero qualifier. The result of the study could be incorrect,
+    or the function might crash, depending on the pattern.
+
+4.  Caseless matching was not working for non-ASCII characters in back
+    references. For example, /(\x{de})\1/8i was not matching \x{de}\x{fe}.
+    It now works when Unicode Property Support is available.
+
+5.  In pcretest, an escape such as \x{de} in the data was always generating
+    a UTF-8 string, even in non-UTF-8 mode. Now it generates a single byte in
+    non-UTF-8 mode. If the value is greater than 255, it gives a warning about
+    truncation.
+
+6.  Minor bugfix in pcrecpp.cc (change "" == ... to NULL == ...).
+
+7.  Added two (int) casts to pcregrep when printing the difference of two
+    pointers, in case they are 64-bit values.
+
+8.  Added comments about Mac OS X stack usage to the pcrestack man page and to
+    test 2 if it fails.
+
+9.  Added PCRE_CALL_CONVENTION just before the names of all exported functions,
+    and a #define of that name to empty if it is not externally set. This is to
+    allow users of MSVC to set it if necessary.
+
+10. The PCRE_EXP_DEFN macro which precedes exported functions was missing from
+    the convenience functions in the pcre_get.c source file.
+
+11. An option change at the start of a pattern that had top-level alternatives
+    could cause overwriting and/or a crash. This command provoked a crash in
+    some environments:
+
+      printf "/(?i)[\xc3\xa9\xc3\xbd]|[\xc3\xa9\xc3\xbdA]/8\n" | pcretest
+
+    This potential security problem was recorded as CVE-2008-2371.
+
+12. For a pattern where the match had to start at the beginning or immediately
+    after a newline (e.g /.*anything/ without the DOTALL flag), pcre_exec() and
+    pcre_dfa_exec() could read past the end of the passed subject if there was
+    no match. To help with detecting such bugs (e.g. with valgrind), I modified
+    pcretest so that it places the subject at the end of its malloc-ed buffer.
+
+13. The change to pcretest in 12 above threw up a couple more cases when pcre_
+    exec() might read past the end of the data buffer in UTF-8 mode.
+
+14. A similar bug to 7.3/2 existed when the PCRE_FIRSTLINE option was set and
+    the data contained the byte 0x85 as part of a UTF-8 character within its
+    first line. This applied both to normal and DFA matching.
+
+15. Lazy qualifiers were not working in some cases in UTF-8 mode. For example,
+    /^[^d]*?$/8 failed to match "abc".
+
+16. Added a missing copyright notice to pcrecpp_internal.h.
+
+17. Make it more clear in the documentation that values returned from
+    pcre_exec() in ovector are byte offsets, not character counts.
+
+18. Tidied a few places to stop certain compilers from issuing warnings.
+
+19. Updated the Virtual Pascal + BCC files to compile the latest v7.7, as
+    supplied by Stefan Weber. I made a further small update for 7.8 because
+    there is a change of source arrangements: the pcre_searchfuncs.c module is
+    replaced by pcre_ucd.c.
+
+
+Version 7.7 07-May-08
+---------------------
+
+1.  Applied Craig's patch to sort out a long long problem: "If we can't convert
+    a string to a long long, pretend we don't even have a long long." This is
+    done by checking for the strtoq, strtoll, and _strtoi64 functions.
+
+2.  Applied Craig's patch to pcrecpp.cc to restore ABI compatibility with
+    pre-7.6 versions, which defined a global no_arg variable instead of putting
+    it in the RE class. (See also #8 below.)
+
+3.  Remove a line of dead code, identified by coverity and reported by Nuno
+    Lopes.
+
+4.  Fixed two related pcregrep bugs involving -r with --include or --exclude:
+
+    (1) The include/exclude patterns were being applied to the whole pathnames
+        of files, instead of just to the final components.
+
+    (2) If there was more than one level of directory, the subdirectories were
+        skipped unless they satisfied the include/exclude conditions. This is
+        inconsistent with GNU grep (and could even be seen as contrary to the
+        pcregrep specification - which I improved to make it absolutely clear).
+        The action now is always to scan all levels of directory, and just
+        apply the include/exclude patterns to regular files.
+
+5.  Added the --include_dir and --exclude_dir patterns to pcregrep, and used
+    --exclude_dir in the tests to avoid scanning .svn directories.
+
+6.  Applied Craig's patch to the QuoteMeta function so that it escapes the
+    NUL character as backslash + 0 rather than backslash + NUL, because PCRE
+    doesn't support NULs in patterns.
+
+7.  Added some missing "const"s to declarations of static tables in
+    pcre_compile.c and pcre_dfa_exec.c.
+
+8.  Applied Craig's patch to pcrecpp.cc to fix a problem in OS X that was
+    caused by fix #2  above. (Subsequently also a second patch to fix the
+    first patch. And a third patch - this was a messy problem.)
+
+9.  Applied Craig's patch to remove the use of push_back().
+
+10. Applied Alan Lehotsky's patch to add REG_STARTEND support to the POSIX
+    matching function regexec().
+
+11. Added support for the Oniguruma syntax \g<name>, \g<n>, \g'name', \g'n',
+    which, however, unlike Perl's \g{...}, are subroutine calls, not back
+    references. PCRE supports relative numbers with this syntax (I don't think
+    Oniguruma does).
+
+12. Previously, a group with a zero repeat such as (...){0} was completely
+    omitted from the compiled regex. However, this means that if the group
+    was called as a subroutine from elsewhere in the pattern, things went wrong
+    (an internal error was given). Such groups are now left in the compiled
+    pattern, with a new opcode that causes them to be skipped at execution
+    time.
+
+13. Added the PCRE_JAVASCRIPT_COMPAT option. This makes the following changes
+    to the way PCRE behaves:
+
+    (a) A lone ] character is dis-allowed (Perl treats it as data).
+
+    (b) A back reference to an unmatched subpattern matches an empty string
+        (Perl fails the current match path).
+
+    (c) A data ] in a character class must be notated as \] because if the
+        first data character in a class is ], it defines an empty class. (In
+        Perl it is not possible to have an empty class.) The empty class []
+        never matches; it forces failure and is equivalent to (*FAIL) or (?!).
+        The negative empty class [^] matches any one character, independently
+        of the DOTALL setting.
+
+14. A pattern such as /(?2)[]a()b](abc)/ which had a forward reference to a
+    non-existent subpattern following a character class starting with ']' and
+    containing () gave an internal compiling error instead of "reference to
+    non-existent subpattern". Fortunately, when the pattern did exist, the
+    compiled code was correct. (When scanning forwards to check for the
+    existence of the subpattern, it was treating the data ']' as terminating
+    the class, so got the count wrong. When actually compiling, the reference
+    was subsequently set up correctly.)
+
+15. The "always fail" assertion (?!) is optimzed to (*FAIL) by pcre_compile;
+    it was being rejected as not supported by pcre_dfa_exec(), even though
+    other assertions are supported. I have made pcre_dfa_exec() support
+    (*FAIL).
+
+16. The implementation of 13c above involved the invention of a new opcode,
+    OP_ALLANY, which is like OP_ANY but doesn't check the /s flag. Since /s
+    cannot be changed at match time, I realized I could make a small
+    improvement to matching performance by compiling OP_ALLANY instead of
+    OP_ANY for "." when DOTALL was set, and then removing the runtime tests
+    on the OP_ANY path.
+
+17. Compiling pcretest on Windows with readline support failed without the
+    following two fixes: (1) Make the unistd.h include conditional on
+    HAVE_UNISTD_H; (2) #define isatty and fileno as _isatty and _fileno.
+
+18. Changed CMakeLists.txt and cmake/FindReadline.cmake to arrange for the
+    ncurses library to be included for pcretest when ReadLine support is
+    requested, but also to allow for it to be overridden. This patch came from
+    Daniel Bergström.
+
+19. There was a typo in the file ucpinternal.h where f0_rangeflag was defined
+    as 0x00f00000 instead of 0x00800000. Luckily, this would not have caused
+    any errors with the current Unicode tables. Thanks to Peter Kankowski for
+    spotting this.
+
+
+Version 7.6 28-Jan-08
+---------------------
+
+1.  A character class containing a very large number of characters with
+    codepoints greater than 255 (in UTF-8 mode, of course) caused a buffer
+    overflow.
+
+2.  Patch to cut out the "long long" test in pcrecpp_unittest when
+    HAVE_LONG_LONG is not defined.
+
+3.  Applied Christian Ehrlicher's patch to update the CMake build files to
+    bring them up to date and include new features. This patch includes:
+
+    - Fixed PH's badly added libz and libbz2 support.
+    - Fixed a problem with static linking.
+    - Added pcredemo. [But later removed - see 7 below.]
+    - Fixed dftables problem and added an option.
+    - Added a number of HAVE_XXX tests, including HAVE_WINDOWS_H and
+        HAVE_LONG_LONG.
+    - Added readline support for pcretest.
+    - Added an listing of the option settings after cmake has run.
+
+4.  A user submitted a patch to Makefile that makes it easy to create
+    "pcre.dll" under mingw when using Configure/Make. I added stuff to
+    Makefile.am that cause it to include this special target, without
+    affecting anything else. Note that the same mingw target plus all
+    the other distribution libraries and programs are now supported
+    when configuring with CMake (see 6 below) instead of with
+    Configure/Make.
+
+5.  Applied Craig's patch that moves no_arg into the RE class in the C++ code.
+    This is an attempt to solve the reported problem "pcrecpp::no_arg is not
+    exported in the Windows port". It has not yet been confirmed that the patch
+    solves the problem, but it does no harm.
+
+6.  Applied Sheri's patch to CMakeLists.txt to add NON_STANDARD_LIB_PREFIX and
+    NON_STANDARD_LIB_SUFFIX for dll names built with mingw when configured
+    with CMake, and also correct the comment about stack recursion.
+
+7.  Remove the automatic building of pcredemo from the ./configure system and
+    from CMakeLists.txt. The whole idea of pcredemo.c is that it is an example
+    of a program that users should build themselves after PCRE is installed, so
+    building it automatically is not really right. What is more, it gave
+    trouble in some build environments.
+
+8.  Further tidies to CMakeLists.txt from Sheri and Christian.
+
+
+Version 7.5 10-Jan-08
+---------------------
+
+1.  Applied a patch from Craig: "This patch makes it possible to 'ignore'
+    values in parens when parsing an RE using the C++ wrapper."
+
+2.  Negative specials like \S did not work in character classes in UTF-8 mode.
+    Characters greater than 255 were excluded from the class instead of being
+    included.
+
+3.  The same bug as (2) above applied to negated POSIX classes such as
+    [:^space:].
+
+4.  PCRECPP_STATIC was referenced in pcrecpp_internal.h, but nowhere was it
+    defined or documented. It seems to have been a typo for PCRE_STATIC, so
+    I have changed it.
+
+5.  The construct (?&) was not diagnosed as a syntax error (it referenced the
+    first named subpattern) and a construct such as (?&a) would reference the
+    first named subpattern whose name started with "a" (in other words, the
+    length check was missing). Both these problems are fixed. "Subpattern name
+    expected" is now given for (?&) (a zero-length name), and this patch also
+    makes it give the same error for \k'' (previously it complained that that
+    was a reference to a non-existent subpattern).
+
+6.  The erroneous patterns (?+-a) and (?-+a) give different error messages;
+    this is right because (?- can be followed by option settings as well as by
+    digits. I have, however, made the messages clearer.
+
+7.  Patterns such as (?(1)a|b) (a pattern that contains fewer subpatterns
+    than the number used in the conditional) now cause a compile-time error.
+    This is actually not compatible with Perl, which accepts such patterns, but
+    treats the conditional as always being FALSE (as PCRE used to), but it
+    seems to me that giving a diagnostic is better.
+
+8.  Change "alphameric" to the more common word "alphanumeric" in comments
+    and messages.
+
+9.  Fix two occurrences of "backslash" in comments that should have been
+    "backspace".
+
+10. Remove two redundant lines of code that can never be obeyed (their function
+    was moved elsewhere).
+
+11. The program that makes PCRE's Unicode character property table had a bug
+    which caused it to generate incorrect table entries for sequences of
+    characters that have the same character type, but are in different scripts.
+    It amalgamated them into a single range, with the script of the first of
+    them. In other words, some characters were in the wrong script. There were
+    thirteen such cases, affecting characters in the following ranges:
+
+      U+002b0 - U+002c1
+      U+0060c - U+0060d
+      U+0061e - U+00612
+      U+0064b - U+0065e
+      U+0074d - U+0076d
+      U+01800 - U+01805
+      U+01d00 - U+01d77
+      U+01d9b - U+01dbf
+      U+0200b - U+0200f
+      U+030fc - U+030fe
+      U+03260 - U+0327f
+      U+0fb46 - U+0fbb1
+      U+10450 - U+1049d
+
+12. The -o option (show only the matching part of a line) for pcregrep was not
+    compatible with GNU grep in that, if there was more than one match in a
+    line, it showed only the first of them. It now behaves in the same way as
+    GNU grep.
+
+13. If the -o and -v options were combined for pcregrep, it printed a blank
+    line for every non-matching line. GNU grep prints nothing, and pcregrep now
+    does the same. The return code can be used to tell if there were any
+    non-matching lines.
+
+14. Added --file-offsets and --line-offsets to pcregrep.
+
+15. The pattern (?=something)(?R) was not being diagnosed as a potentially
+    infinitely looping recursion. The bug was that positive lookaheads were not
+    being skipped when checking for a possible empty match (negative lookaheads
+    and both kinds of lookbehind were skipped).
+
+16. Fixed two typos in the Windows-only code in pcregrep.c, and moved the
+    inclusion of <windows.h> to before rather than after the definition of
+    INVALID_FILE_ATTRIBUTES (patch from David Byron).
+
+17. Specifying a possessive quantifier with a specific limit for a Unicode
+    character property caused pcre_compile() to compile bad code, which led at
+    runtime to PCRE_ERROR_INTERNAL (-14). Examples of patterns that caused this
+    are: /\p{Zl}{2,3}+/8 and /\p{Cc}{2}+/8. It was the possessive "+" that
+    caused the error; without that there was no problem.
+
+18. Added --enable-pcregrep-libz and --enable-pcregrep-libbz2.
+
+19. Added --enable-pcretest-libreadline.
+
+20. In pcrecpp.cc, the variable 'count' was incremented twice in
+    RE::GlobalReplace(). As a result, the number of replacements returned was
+    double what it should be. I removed one of the increments, but Craig sent a
+    later patch that removed the other one (the right fix) and added unit tests
+    that check the return values (which was not done before).
+
+21. Several CMake things:
+
+    (1) Arranged that, when cmake is used on Unix, the libraries end up with
+        the names libpcre and libpcreposix, not just pcre and pcreposix.
+
+    (2) The above change means that pcretest and pcregrep are now correctly
+        linked with the newly-built libraries, not previously installed ones.
+
+    (3) Added PCRE_SUPPORT_LIBREADLINE, PCRE_SUPPORT_LIBZ, PCRE_SUPPORT_LIBBZ2.
+
+22. In UTF-8 mode, with newline set to "any", a pattern such as .*a.*=.b.*
+    crashed when matching a string such as a\x{2029}b (note that \x{2029} is a
+    UTF-8 newline character). The key issue is that the pattern starts .*;
+    this means that the match must be either at the beginning, or after a
+    newline. The bug was in the code for advancing after a failed match and
+    checking that the new position followed a newline. It was not taking
+    account of UTF-8 characters correctly.
+
+23. PCRE was behaving differently from Perl in the way it recognized POSIX
+    character classes. PCRE was not treating the sequence [:...:] as a
+    character class unless the ... were all letters. Perl, however, seems to
+    allow any characters between [: and :], though of course it rejects as
+    unknown any "names" that contain non-letters, because all the known class
+    names consist only of letters. Thus, Perl gives an error for [[:1234:]],
+    for example, whereas PCRE did not - it did not recognize a POSIX character
+    class. This seemed a bit dangerous, so the code has been changed to be
+    closer to Perl. The behaviour is not identical to Perl, because PCRE will
+    diagnose an unknown class for, for example, [[:l\ower:]] where Perl will
+    treat it as [[:lower:]]. However, PCRE does now give "unknown" errors where
+    Perl does, and where it didn't before.
+
+24. Rewrite so as to remove the single use of %n from pcregrep because in some
+    Windows environments %n is disabled by default.
+
+
+Version 7.4 21-Sep-07
+---------------------
+
+1.  Change 7.3/28 was implemented for classes by looking at the bitmap. This
+    means that a class such as [\s] counted as "explicit reference to CR or
+    LF". That isn't really right - the whole point of the change was to try to
+    help when there was an actual mention of one of the two characters. So now
+    the change happens only if \r or \n (or a literal CR or LF) character is
+    encountered.
+
+2.  The 32-bit options word was also used for 6 internal flags, but the numbers
+    of both had grown to the point where there were only 3 bits left.
+    Fortunately, there was spare space in the data structure, and so I have
+    moved the internal flags into a new 16-bit field to free up more option
+    bits.
+
+3.  The appearance of (?J) at the start of a pattern set the DUPNAMES option,
+    but did not set the internal JCHANGED flag - either of these is enough to
+    control the way the "get" function works - but the PCRE_INFO_JCHANGED
+    facility is supposed to tell if (?J) was ever used, so now (?J) at the
+    start sets both bits.
+
+4.  Added options (at build time, compile time, exec time) to change \R from
+    matching any Unicode line ending sequence to just matching CR, LF, or CRLF.
+
+5.  doc/pcresyntax.html was missing from the distribution.
+
+6.  Put back the definition of PCRE_ERROR_NULLWSLIMIT, for backward
+    compatibility, even though it is no longer used.
+
+7.  Added macro for snprintf to pcrecpp_unittest.cc and also for strtoll and
+    strtoull to pcrecpp.cc to select the available functions in WIN32 when the
+    windows.h file is present (where different names are used). [This was
+    reversed later after testing - see 16 below.]
+
+8.  Changed all #include <config.h> to #include "config.h". There were also
+    some further <pcre.h> cases that I changed to "pcre.h".
+
+9.  When pcregrep was used with the --colour option, it missed the line ending
+    sequence off the lines that it output.
+
+10. It was pointed out to me that arrays of string pointers cause lots of
+    relocations when a shared library is dynamically loaded. A technique of
+    using a single long string with a table of offsets can drastically reduce
+    these. I have refactored PCRE in four places to do this. The result is
+    dramatic:
+
+      Originally:                          290
+      After changing UCP table:            187
+      After changing error message table:   43
+      After changing table of "verbs"       36
+      After changing table of Posix names   22
+
+    Thanks to the folks working on Gregex for glib for this insight.
+
+11. --disable-stack-for-recursion caused compiling to fail unless -enable-
+    unicode-properties was also set.
+
+12. Updated the tests so that they work when \R is defaulted to ANYCRLF.
+
+13. Added checks for ANY and ANYCRLF to pcrecpp.cc where it previously
+    checked only for CRLF.
+
+14. Added casts to pcretest.c to avoid compiler warnings.
+
+15. Added Craig's patch to various pcrecpp modules to avoid compiler warnings.
+
+16. Added Craig's patch to remove the WINDOWS_H tests, that were not working,
+    and instead check for _strtoi64 explicitly, and avoid the use of snprintf()
+    entirely. This removes changes made in 7 above.
+
+17. The CMake files have been updated, and there is now more information about
+    building with CMake in the NON-UNIX-USE document.
+
+
+Version 7.3 28-Aug-07
+---------------------
+
+ 1. In the rejigging of the build system that eventually resulted in 7.1, the
+    line "#include <pcre.h>" was included in pcre_internal.h. The use of angle
+    brackets there is not right, since it causes compilers to look for an
+    installed pcre.h, not the version that is in the source that is being
+    compiled (which of course may be different). I have changed it back to:
+
+      #include "pcre.h"
+
+    I have a vague recollection that the change was concerned with compiling in
+    different directories, but in the new build system, that is taken care of
+    by the VPATH setting the Makefile.
+
+ 2. The pattern .*$ when run in not-DOTALL UTF-8 mode with newline=any failed
+    when the subject happened to end in the byte 0x85 (e.g. if the last
+    character was \x{1ec5}). *Character* 0x85 is one of the "any" newline
+    characters but of course it shouldn't be taken as a newline when it is part
+    of another character. The bug was that, for an unlimited repeat of . in
+    not-DOTALL UTF-8 mode, PCRE was advancing by bytes rather than by
+    characters when looking for a newline.
+
+ 3. A small performance improvement in the DOTALL UTF-8 mode .* case.
+
+ 4. Debugging: adjusted the names of opcodes for different kinds of parentheses
+    in debug output.
+
+ 5. Arrange to use "%I64d" instead of "%lld" and "%I64u" instead of "%llu" for
+    long printing in the pcrecpp unittest when running under MinGW.
+
+ 6. ESC_K was left out of the EBCDIC table.
+
+ 7. Change 7.0/38 introduced a new limit on the number of nested non-capturing
+    parentheses; I made it 1000, which seemed large enough. Unfortunately, the
+    limit also applies to "virtual nesting" when a pattern is recursive, and in
+    this case 1000 isn't so big. I have been able to remove this limit at the
+    expense of backing off one optimization in certain circumstances. Normally,
+    when pcre_exec() would call its internal match() function recursively and
+    immediately return the result unconditionally, it uses a "tail recursion"
+    feature to save stack. However, when a subpattern that can match an empty
+    string has an unlimited repetition quantifier, it no longer makes this
+    optimization. That gives it a stack frame in which to save the data for
+    checking that an empty string has been matched. Previously this was taken
+    from the 1000-entry workspace that had been reserved. So now there is no
+    explicit limit, but more stack is used.
+
+ 8. Applied Daniel's patches to solve problems with the import/export magic
+    syntax that is required for Windows, and which was going wrong for the
+    pcreposix and pcrecpp parts of the library. These were overlooked when this
+    problem was solved for the main library.
+
+ 9. There were some crude static tests to avoid integer overflow when computing
+    the size of patterns that contain repeated groups with explicit upper
+    limits. As the maximum quantifier is 65535, the maximum group length was
+    set at 30,000 so that the product of these two numbers did not overflow a
+    32-bit integer. However, it turns out that people want to use groups that
+    are longer than 30,000 bytes (though not repeat them that many times).
+    Change 7.0/17 (the refactoring of the way the pattern size is computed) has
+    made it possible to implement the integer overflow checks in a much more
+    dynamic way, which I have now done. The artificial limitation on group
+    length has been removed - we now have only the limit on the total length of
+    the compiled pattern, which depends on the LINK_SIZE setting.
+
+10. Fixed a bug in the documentation for get/copy named substring when
+    duplicate names are permitted. If none of the named substrings are set, the
+    functions return PCRE_ERROR_NOSUBSTRING (7); the doc said they returned an
+    empty string.
+
+11. Because Perl interprets \Q...\E at a high level, and ignores orphan \E
+    instances, patterns such as [\Q\E] or [\E] or even [^\E] cause an error,
+    because the ] is interpreted as the first data character and the
+    terminating ] is not found. PCRE has been made compatible with Perl in this
+    regard. Previously, it interpreted [\Q\E] as an empty class, and [\E] could
+    cause memory overwriting.
+
+10. Like Perl, PCRE automatically breaks an unlimited repeat after an empty
+    string has been matched (to stop an infinite loop). It was not recognizing
+    a conditional subpattern that could match an empty string if that
+    subpattern was within another subpattern. For example, it looped when
+    trying to match  (((?(1)X|))*)  but it was OK with  ((?(1)X|)*)  where the
+    condition was not nested. This bug has been fixed.
+
+12. A pattern like \X?\d or \P{L}?\d in non-UTF-8 mode could cause a backtrack
+    past the start of the subject in the presence of bytes with the top bit
+    set, for example "\x8aBCD".
+
+13. Added Perl 5.10 experimental backtracking controls (*FAIL), (*F), (*PRUNE),
+    (*SKIP), (*THEN), (*COMMIT), and (*ACCEPT).
+
+14. Optimized (?!) to (*FAIL).
+
+15. Updated the test for a valid UTF-8 string to conform to the later RFC 3629.
+    This restricts code points to be within the range 0 to 0x10FFFF, excluding
+    the "low surrogate" sequence 0xD800 to 0xDFFF. Previously, PCRE allowed the
+    full range 0 to 0x7FFFFFFF, as defined by RFC 2279. Internally, it still
+    does: it's just the validity check that is more restrictive.
+
+16. Inserted checks for integer overflows during escape sequence (backslash)
+    processing, and also fixed erroneous offset values for syntax errors during
+    backslash processing.
+
+17. Fixed another case of looking too far back in non-UTF-8 mode (cf 12 above)
+    for patterns like [\PPP\x8a]{1,}\x80 with the subject "A\x80".
+
+18. An unterminated class in a pattern like (?1)\c[ with a "forward reference"
+    caused an overrun.
+
+19. A pattern like (?:[\PPa*]*){8,} which had an "extended class" (one with
+    something other than just ASCII characters) inside a group that had an
+    unlimited repeat caused a loop at compile time (while checking to see
+    whether the group could match an empty string).
+
+20. Debugging a pattern containing \p or \P could cause a crash. For example,
+    [\P{Any}] did so. (Error in the code for printing property names.)
+
+21. An orphan \E inside a character class could cause a crash.
+
+22. A repeated capturing bracket such as (A)? could cause a wild memory
+    reference during compilation.
+
+23. There are several functions in pcre_compile() that scan along a compiled
+    expression for various reasons (e.g. to see if it's fixed length for look
+    behind). There were bugs in these functions when a repeated \p or \P was
+    present in the pattern. These operators have additional parameters compared
+    with \d, etc, and these were not being taken into account when moving along
+    the compiled data. Specifically:
+
+    (a) A item such as \p{Yi}{3} in a lookbehind was not treated as fixed
+        length.
+
+    (b) An item such as \pL+ within a repeated group could cause crashes or
+        loops.
+
+    (c) A pattern such as \p{Yi}+(\P{Yi}+)(?1) could give an incorrect
+        "reference to non-existent subpattern" error.
+
+    (d) A pattern like (\P{Yi}{2}\277)? could loop at compile time.
+
+24. A repeated \S or \W in UTF-8 mode could give wrong answers when multibyte
+    characters were involved (for example /\S{2}/8g with "A\x{a3}BC").
+
+25. Using pcregrep in multiline, inverted mode (-Mv) caused it to loop.
+
+26. Patterns such as [\P{Yi}A] which include \p or \P and just one other
+    character were causing crashes (broken optimization).
+
+27. Patterns such as (\P{Yi}*\277)* (group with possible zero repeat containing
+    \p or \P) caused a compile-time loop.
+
+28. More problems have arisen in unanchored patterns when CRLF is a valid line
+    break. For example, the unstudied pattern [\r\n]A does not match the string
+    "\r\nA" because change 7.0/46 below moves the current point on by two
+    characters after failing to match at the start. However, the pattern \nA
+    *does* match, because it doesn't start till \n, and if [\r\n]A is studied,
+    the same is true. There doesn't seem any very clean way out of this, but
+    what I have chosen to do makes the common cases work: PCRE now takes note
+    of whether there can be an explicit match for \r or \n anywhere in the
+    pattern, and if so, 7.0/46 no longer applies. As part of this change,
+    there's a new PCRE_INFO_HASCRORLF option for finding out whether a compiled
+    pattern has explicit CR or LF references.
+
+29. Added (*CR) etc for changing newline setting at start of pattern.
+
+
+Version 7.2 19-Jun-07
+---------------------
+
+ 1. If the fr_FR locale cannot be found for test 3, try the "french" locale,
+    which is apparently normally available under Windows.
+
+ 2. Re-jig the pcregrep tests with different newline settings in an attempt
+    to make them independent of the local environment's newline setting.
+
+ 3. Add code to configure.ac to remove -g from the CFLAGS default settings.
+
+ 4. Some of the "internals" tests were previously cut out when the link size
+    was not 2, because the output contained actual offsets. The recent new
+    "Z" feature of pcretest means that these can be cut out, making the tests
+    usable with all link sizes.
+
+ 5. Implemented Stan Switzer's goto replacement for longjmp() when not using
+    stack recursion. This gives a massive performance boost under BSD, but just
+    a small improvement under Linux. However, it saves one field in the frame
+    in all cases.
+
+ 6. Added more features from the forthcoming Perl 5.10:
+
+    (a) (?-n) (where n is a string of digits) is a relative subroutine or
+        recursion call. It refers to the nth most recently opened parentheses.
+
+    (b) (?+n) is also a relative subroutine call; it refers to the nth next
+        to be opened parentheses.
+
+    (c) Conditions that refer to capturing parentheses can be specified
+        relatively, for example, (?(-2)... or (?(+3)...
+
+    (d) \K resets the start of the current match so that everything before
+        is not part of it.
+
+    (e) \k{name} is synonymous with \k<name> and \k'name' (.NET compatible).
+
+    (f) \g{name} is another synonym - part of Perl 5.10's unification of
+        reference syntax.
+
+    (g) (?| introduces a group in which the numbering of parentheses in each
+        alternative starts with the same number.
+
+    (h) \h, \H, \v, and \V match horizontal and vertical whitespace.
+
+ 7. Added two new calls to pcre_fullinfo(): PCRE_INFO_OKPARTIAL and
+    PCRE_INFO_JCHANGED.
+
+ 8. A pattern such as  (.*(.)?)*  caused pcre_exec() to fail by either not
+    terminating or by crashing. Diagnosed by Viktor Griph; it was in the code
+    for detecting groups that can match an empty string.
+
+ 9. A pattern with a very large number of alternatives (more than several
+    hundred) was running out of internal workspace during the pre-compile
+    phase, where pcre_compile() figures out how much memory will be needed. A
+    bit of new cunning has reduced the workspace needed for groups with
+    alternatives. The 1000-alternative test pattern now uses 12 bytes of
+    workspace instead of running out of the 4096 that are available.
+
+10. Inserted some missing (unsigned int) casts to get rid of compiler warnings.
+
+11. Applied patch from Google to remove an optimization that didn't quite work.
+    The report of the bug said:
+
+      pcrecpp::RE("a*").FullMatch("aaa") matches, while
+      pcrecpp::RE("a*?").FullMatch("aaa") does not, and
+      pcrecpp::RE("a*?\\z").FullMatch("aaa") does again.
+
+12. If \p or \P was used in non-UTF-8 mode on a character greater than 127
+    it matched the wrong number of bytes.
+
+
+Version 7.1 24-Apr-07
+---------------------
+
+ 1. Applied Bob Rossi and Daniel G's patches to convert the build system to one
+    that is more "standard", making use of automake and other Autotools. There
+    is some re-arrangement of the files and adjustment of comments consequent
+    on this.
+
+ 2. Part of the patch fixed a problem with the pcregrep tests. The test of -r
+    for recursive directory scanning broke on some systems because the files
+    are not scanned in any specific order and on different systems the order
+    was different. A call to "sort" has been inserted into RunGrepTest for the
+    approprate test as a short-term fix. In the longer term there may be an
+    alternative.
+
+ 3. I had an email from Eric Raymond about problems translating some of PCRE's
+    man pages to HTML (despite the fact that I distribute HTML pages, some
+    people do their own conversions for various reasons). The problems
+    concerned the use of low-level troff macros .br and .in. I have therefore
+    removed all such uses from the man pages (some were redundant, some could
+    be replaced by .nf/.fi pairs). The 132html script that I use to generate
+    HTML has been updated to handle .nf/.fi and to complain if it encounters
+    .br or .in.
+
+ 4. Updated comments in configure.ac that get placed in config.h.in and also
+    arranged for config.h to be included in the distribution, with the name
+    config.h.generic, for the benefit of those who have to compile without
+    Autotools (compare pcre.h, which is now distributed as pcre.h.generic).
+
+ 5. Updated the support (such as it is) for Virtual Pascal, thanks to Stefan
+    Weber: (1) pcre_internal.h was missing some function renames; (2) updated
+    makevp.bat for the current PCRE, using the additional files
+    makevp_c.txt, makevp_l.txt, and pcregexp.pas.
+
+ 6. A Windows user reported a minor discrepancy with test 2, which turned out
+    to be caused by a trailing space on an input line that had got lost in his
+    copy. The trailing space was an accident, so I've just removed it.
+
+ 7. Add -Wl,-R... flags in pcre-config.in for *BSD* systems, as I'm told
+    that is needed.
+
+ 8. Mark ucp_table (in ucptable.h) and ucp_gentype (in pcre_ucp_searchfuncs.c)
+    as "const" (a) because they are and (b) because it helps the PHP
+    maintainers who have recently made a script to detect big data structures
+    in the php code that should be moved to the .rodata section. I remembered
+    to update Builducptable as well, so it won't revert if ucptable.h is ever
+    re-created.
+
+ 9. Added some extra #ifdef SUPPORT_UTF8 conditionals into pcretest.c,
+    pcre_printint.src, pcre_compile.c, pcre_study.c, and pcre_tables.c, in
+    order to be able to cut out the UTF-8 tables in the latter when UTF-8
+    support is not required. This saves 1.5-2K of code, which is important in
+    some applications.
+
+    Later: more #ifdefs are needed in pcre_ord2utf8.c and pcre_valid_utf8.c
+    so as not to refer to the tables, even though these functions will never be
+    called when UTF-8 support is disabled. Otherwise there are problems with a
+    shared library.
+
+10. Fixed two bugs in the emulated memmove() function in pcre_internal.h:
+
+    (a) It was defining its arguments as char * instead of void *.
+
+    (b) It was assuming that all moves were upwards in memory; this was true
+        a long time ago when I wrote it, but is no longer the case.
+
+    The emulated memove() is provided for those environments that have neither
+    memmove() nor bcopy(). I didn't think anyone used it these days, but that
+    is clearly not the case, as these two bugs were recently reported.
+
+11. The script PrepareRelease is now distributed: it calls 132html, CleanTxt,
+    and Detrail to create the HTML documentation, the .txt form of the man
+    pages, and it removes trailing spaces from listed files. It also creates
+    pcre.h.generic and config.h.generic from pcre.h and config.h. In the latter
+    case, it wraps all the #defines with #ifndefs. This script should be run
+    before "make dist".
+
+12. Fixed two fairly obscure bugs concerned with quantified caseless matching
+    with Unicode property support.
+
+    (a) For a maximizing quantifier, if the two different cases of the
+        character were of different lengths in their UTF-8 codings (there are
+        some cases like this - I found 11), and the matching function had to
+        back up over a mixture of the two cases, it incorrectly assumed they
+        were both the same length.
+
+    (b) When PCRE was configured to use the heap rather than the stack for
+        recursion during matching, it was not correctly preserving the data for
+        the other case of a UTF-8 character when checking ahead for a match
+        while processing a minimizing repeat. If the check also involved
+        matching a wide character, but failed, corruption could cause an
+        erroneous result when trying to check for a repeat of the original
+        character.
+
+13. Some tidying changes to the testing mechanism:
+
+    (a) The RunTest script now detects the internal link size and whether there
+        is UTF-8 and UCP support by running ./pcretest -C instead of relying on
+        values substituted by "configure". (The RunGrepTest script already did
+        this for UTF-8.) The configure.ac script no longer substitutes the
+        relevant variables.
+
+    (b) The debugging options /B and /D in pcretest show the compiled bytecode
+        with length and offset values. This means that the output is different
+        for different internal link sizes. Test 2 is skipped for link sizes
+        other than 2 because of this, bypassing the problem. Unfortunately,
+        there was also a test in test 3 (the locale tests) that used /B and
+        failed for link sizes other than 2. Rather than cut the whole test out,
+        I have added a new /Z option to pcretest that replaces the length and
+        offset values with spaces. This is now used to make test 3 independent
+        of link size. (Test 2 will be tidied up later.)
+
+14. If erroroffset was passed as NULL to pcre_compile, it provoked a
+    segmentation fault instead of returning the appropriate error message.
+
+15. In multiline mode when the newline sequence was set to "any", the pattern
+    ^$ would give a match between the \r and \n of a subject such as "A\r\nB".
+    This doesn't seem right; it now treats the CRLF combination as the line
+    ending, and so does not match in that case. It's only a pattern such as ^$
+    that would hit this one: something like ^ABC$ would have failed after \r
+    and then tried again after \r\n.
+
+16. Changed the comparison command for RunGrepTest from "diff -u" to "diff -ub"
+    in an attempt to make files that differ only in their line terminators
+    compare equal. This works on Linux.
+
+17. Under certain error circumstances pcregrep might try to free random memory
+    as it exited. This is now fixed, thanks to valgrind.
+
+19. In pcretest, if the pattern /(?m)^$/g<any> was matched against the string
+    "abc\r\n\r\n", it found an unwanted second match after the second \r. This
+    was because its rules for how to advance for /g after matching an empty
+    string at the end of a line did not allow for this case. They now check for
+    it specially.
+
+20. pcretest is supposed to handle patterns and data of any length, by
+    extending its buffers when necessary. It was getting this wrong when the
+    buffer for a data line had to be extended.
+
+21. Added PCRE_NEWLINE_ANYCRLF which is like ANY, but matches only CR, LF, or
+    CRLF as a newline sequence.
+
+22. Code for handling Unicode properties in pcre_dfa_exec() wasn't being cut
+    out by #ifdef SUPPORT_UCP. This did no harm, as it could never be used, but
+    I have nevertheless tidied it up.
+
+23. Added some casts to kill warnings from HP-UX ia64 compiler.
+
+24. Added a man page for pcre-config.
+
+
+Version 7.0 19-Dec-06
+---------------------
+
+ 1. Fixed a signed/unsigned compiler warning in pcre_compile.c, shown up by
+    moving to gcc 4.1.1.
+
+ 2. The -S option for pcretest uses setrlimit(); I had omitted to #include
+    sys/time.h, which is documented as needed for this function. It doesn't
+    seem to matter on Linux, but it showed up on some releases of OS X.
+
+ 3. It seems that there are systems where bytes whose values are greater than
+    127 match isprint() in the "C" locale. The "C" locale should be the
+    default when a C program starts up. In most systems, only ASCII printing
+    characters match isprint(). This difference caused the output from pcretest
+    to vary, making some of the tests fail. I have changed pcretest so that:
+
+    (a) When it is outputting text in the compiled version of a pattern, bytes
+        other than 32-126 are always shown as hex escapes.
+
+    (b) When it is outputting text that is a matched part of a subject string,
+        it does the same, unless a different locale has been set for the match
+        (using the /L modifier). In this case, it uses isprint() to decide.
+
+ 4. Fixed a major bug that caused incorrect computation of the amount of memory
+    required for a compiled pattern when options that changed within the
+    pattern affected the logic of the preliminary scan that determines the
+    length. The relevant options are -x, and -i in UTF-8 mode. The result was
+    that the computed length was too small. The symptoms of this bug were
+    either the PCRE error "internal error: code overflow" from pcre_compile(),
+    or a glibc crash with a message such as "pcretest: free(): invalid next
+    size (fast)". Examples of patterns that provoked this bug (shown in
+    pcretest format) are:
+
+      /(?-x: )/x
+      /(?x)(?-x: \s*#\s*)/
+      /((?i)[\x{c0}])/8
+      /(?i:[\x{c0}])/8
+
+    HOWEVER: Change 17 below makes this fix obsolete as the memory computation
+    is now done differently.
+
+ 5. Applied patches from Google to: (a) add a QuoteMeta function to the C++
+    wrapper classes; (b) implement a new function in the C++ scanner that is
+    more efficient than the old way of doing things because it avoids levels of
+    recursion in the regex matching; (c) add a paragraph to the documentation
+    for the FullMatch() function.
+
+ 6. The escape sequence \n was being treated as whatever was defined as
+    "newline". Not only was this contrary to the documentation, which states
+    that \n is character 10 (hex 0A), but it also went horribly wrong when
+    "newline" was defined as CRLF. This has been fixed.
+
+ 7. In pcre_dfa_exec.c the value of an unsigned integer (the variable called c)
+    was being set to -1 for the "end of line" case (supposedly a value that no
+    character can have). Though this value is never used (the check for end of
+    line is "zero bytes in current character"), it caused compiler complaints.
+    I've changed it to 0xffffffff.
+
+ 8. In pcre_version.c, the version string was being built by a sequence of
+    C macros that, in the event of PCRE_PRERELEASE being defined as an empty
+    string (as it is for production releases) called a macro with an empty
+    argument. The C standard says the result of this is undefined. The gcc
+    compiler treats it as an empty string (which was what was wanted) but it is
+    reported that Visual C gives an error. The source has been hacked around to
+    avoid this problem.
+
+ 9. On the advice of a Windows user, included <io.h> and <fcntl.h> in Windows
+    builds of pcretest, and changed the call to _setmode() to use _O_BINARY
+    instead of 0x8000. Made all the #ifdefs test both _WIN32 and WIN32 (not all
+    of them did).
+
+10. Originally, pcretest opened its input and output without "b"; then I was
+    told that "b" was needed in some environments, so it was added for release
+    5.0 to both the input and output. (It makes no difference on Unix-like
+    systems.) Later I was told that it is wrong for the input on Windows. I've
+    now abstracted the modes into two macros, to make it easier to fiddle with
+    them, and removed "b" from the input mode under Windows.
+
+11. Added pkgconfig support for the C++ wrapper library, libpcrecpp.
+
+12. Added -help and --help to pcretest as an official way of being reminded
+    of the options.
+
+13. Removed some redundant semicolons after macro calls in pcrecpparg.h.in
+    and pcrecpp.cc because they annoy compilers at high warning levels.
+
+14. A bit of tidying/refactoring in pcre_exec.c in the main bumpalong loop.
+
+15. Fixed an occurrence of == in configure.ac that should have been = (shell
+    scripts are not C programs :-) and which was not noticed because it works
+    on Linux.
+
+16. pcretest is supposed to handle any length of pattern and data line (as one
+    line or as a continued sequence of lines) by extending its input buffer if
+    necessary. This feature was broken for very long pattern lines, leading to
+    a string of junk being passed to pcre_compile() if the pattern was longer
+    than about 50K.
+
+17. I have done a major re-factoring of the way pcre_compile() computes the
+    amount of memory needed for a compiled pattern. Previously, there was code
+    that made a preliminary scan of the pattern in order to do this. That was
+    OK when PCRE was new, but as the facilities have expanded, it has become
+    harder and harder to keep it in step with the real compile phase, and there
+    have been a number of bugs (see for example, 4 above). I have now found a
+    cunning way of running the real compile function in a "fake" mode that
+    enables it to compute how much memory it would need, while actually only
+    ever using a few hundred bytes of working memory and without too many
+    tests of the mode. This should make future maintenance and development
+    easier. A side effect of this work is that the limit of 200 on the nesting
+    depth of parentheses has been removed (though this was never a serious
+    limitation, I suspect). However, there is a downside: pcre_compile() now
+    runs more slowly than before (30% or more, depending on the pattern). I
+    hope this isn't a big issue. There is no effect on runtime performance.
+
+18. Fixed a minor bug in pcretest: if a pattern line was not terminated by a
+    newline (only possible for the last line of a file) and it was a
+    pattern that set a locale (followed by /Lsomething), pcretest crashed.
+
+19. Added additional timing features to pcretest. (1) The -tm option now times
+    matching only, not compiling. (2) Both -t and -tm can be followed, as a
+    separate command line item, by a number that specifies the number of
+    repeats to use when timing. The default is 50000; this gives better
+    precision, but takes uncomfortably long for very large patterns.
+
+20. Extended pcre_study() to be more clever in cases where a branch of a
+    subpattern has no definite first character. For example, (a*|b*)[cd] would
+    previously give no result from pcre_study(). Now it recognizes that the
+    first character must be a, b, c, or d.
+
+21. There was an incorrect error "recursive call could loop indefinitely" if
+    a subpattern (or the entire pattern) that was being tested for matching an
+    empty string contained only one non-empty item after a nested subpattern.
+    For example, the pattern (?>\x{100}*)\d(?R) provoked this error
+    incorrectly, because the \d was being skipped in the check.
+
+22. The pcretest program now has a new pattern option /B and a command line
+    option -b, which is equivalent to adding /B to every pattern. This causes
+    it to show the compiled bytecode, without the additional information that
+    -d shows. The effect of -d is now the same as -b with -i (and similarly, /D
+    is the same as /B/I).
+
+23. A new optimization is now able automatically to treat some sequences such
+    as a*b as a*+b. More specifically, if something simple (such as a character
+    or a simple class like \d) has an unlimited quantifier, and is followed by
+    something that cannot possibly match the quantified thing, the quantifier
+    is automatically "possessified".
+
+24. A recursive reference to a subpattern whose number was greater than 39
+    went wrong under certain circumstances in UTF-8 mode. This bug could also
+    have affected the operation of pcre_study().
+
+25. Realized that a little bit of performance could be had by replacing
+    (c & 0xc0) == 0xc0 with c >= 0xc0 when processing UTF-8 characters.
+
+26. Timing data from pcretest is now shown to 4 decimal places instead of 3.
+
+27. Possessive quantifiers such as a++ were previously implemented by turning
+    them into atomic groups such as ($>a+). Now they have their own opcodes,
+    which improves performance. This includes the automatically created ones
+    from 23 above.
+
+28. A pattern such as (?=(\w+))\1: which simulates an atomic group using a
+    lookahead was broken if it was not anchored. PCRE was mistakenly expecting
+    the first matched character to be a colon. This applied both to named and
+    numbered groups.
+
+29. The ucpinternal.h header file was missing its idempotency #ifdef.
+
+30. I was sent a "project" file called libpcre.a.dev which I understand makes
+    building PCRE on Windows easier, so I have included it in the distribution.
+
+31. There is now a check in pcretest against a ridiculously large number being
+    returned by pcre_exec() or pcre_dfa_exec(). If this happens in a /g or /G
+    loop, the loop is abandoned.
+
+32. Forward references to subpatterns in conditions such as (?(2)...) where
+    subpattern 2 is defined later cause pcre_compile() to search forwards in
+    the pattern for the relevant set of parentheses. This search went wrong
+    when there were unescaped parentheses in a character class, parentheses
+    escaped with \Q...\E, or parentheses in a #-comment in /x mode.
+
+33. "Subroutine" calls and backreferences were previously restricted to
+    referencing subpatterns earlier in the regex. This restriction has now
+    been removed.
+
+34. Added a number of extra features that are going to be in Perl 5.10. On the
+    whole, these are just syntactic alternatives for features that PCRE had
+    previously implemented using the Python syntax or my own invention. The
+    other formats are all retained for compatibility.
+
+    (a) Named groups can now be defined as (?<name>...) or (?'name'...) as well
+        as (?P<name>...). The new forms, as well as being in Perl 5.10, are
+        also .NET compatible.
+
+    (b) A recursion or subroutine call to a named group can now be defined as
+        (?&name) as well as (?P>name).
+
+    (c) A backreference to a named group can now be defined as \k<name> or
+        \k'name' as well as (?P=name). The new forms, as well as being in Perl
+        5.10, are also .NET compatible.
+
+    (d) A conditional reference to a named group can now use the syntax
+        (?(<name>) or (?('name') as well as (?(name).
+
+    (e) A "conditional group" of the form (?(DEFINE)...) can be used to define
+        groups (named and numbered) that are never evaluated inline, but can be
+        called as "subroutines" from elsewhere. In effect, the DEFINE condition
+        is always false. There may be only one alternative in such a group.
+
+    (f) A test for recursion can be given as (?(R1).. or (?(R&name)... as well
+        as the simple (?(R). The condition is true only if the most recent
+        recursion is that of the given number or name. It does not search out
+        through the entire recursion stack.
+
+    (g) The escape \gN or \g{N} has been added, where N is a positive or
+        negative number, specifying an absolute or relative reference.
+
+35. Tidied to get rid of some further signed/unsigned compiler warnings and
+    some "unreachable code" warnings.
+
+36. Updated the Unicode property tables to Unicode version 5.0.0. Amongst other
+    things, this adds five new scripts.
+
+37. Perl ignores orphaned \E escapes completely. PCRE now does the same.
+    There were also incompatibilities regarding the handling of \Q..\E inside
+    character classes, for example with patterns like [\Qa\E-\Qz\E] where the
+    hyphen was adjacent to \Q or \E. I hope I've cleared all this up now.
+
+38. Like Perl, PCRE detects when an indefinitely repeated parenthesized group
+    matches an empty string, and forcibly breaks the loop. There were bugs in
+    this code in non-simple cases. For a pattern such as  ^(a()*)*  matched
+    against  aaaa  the result was just "a" rather than "aaaa", for example. Two
+    separate and independent bugs (that affected different cases) have been
+    fixed.
+
+39. Refactored the code to abolish the use of different opcodes for small
+    capturing bracket numbers. This is a tidy that I avoided doing when I
+    removed the limit on the number of capturing brackets for 3.5 back in 2001.
+    The new approach is not only tidier, it makes it possible to reduce the
+    memory needed to fix the previous bug (38).
+
+40. Implemented PCRE_NEWLINE_ANY to recognize any of the Unicode newline
+    sequences (http://unicode.org/unicode/reports/tr18/) as "newline" when
+    processing dot, circumflex, or dollar metacharacters, or #-comments in /x
+    mode.
+
+41. Add \R to match any Unicode newline sequence, as suggested in the Unicode
+    report.
+
+42. Applied patch, originally from Ari Pollak, modified by Google, to allow
+    copy construction and assignment in the C++ wrapper.
+
+43. Updated pcregrep to support "--newline=any". In the process, I fixed a
+    couple of bugs that could have given wrong results in the "--newline=crlf"
+    case.
+
+44. Added a number of casts and did some reorganization of signed/unsigned int
+    variables following suggestions from Dair Grant. Also renamed the variable
+    "this" as "item" because it is a C++ keyword.
+
+45. Arranged for dftables to add
+
+      #include "pcre_internal.h"
+
+    to pcre_chartables.c because without it, gcc 4.x may remove the array
+    definition from the final binary if PCRE is built into a static library and
+    dead code stripping is activated.
+
+46. For an unanchored pattern, if a match attempt fails at the start of a
+    newline sequence, and the newline setting is CRLF or ANY, and the next two
+    characters are CRLF, advance by two characters instead of one.
+
+
+Version 6.7 04-Jul-06
+---------------------
+
+ 1. In order to handle tests when input lines are enormously long, pcretest has
+    been re-factored so that it automatically extends its buffers when
+    necessary. The code is crude, but this _is_ just a test program. The
+    default size has been increased from 32K to 50K.
+
+ 2. The code in pcre_study() was using the value of the re argument before
+    testing it for NULL. (Of course, in any sensible call of the function, it
+    won't be NULL.)
+
+ 3. The memmove() emulation function in pcre_internal.h, which is used on
+    systems that lack both memmove() and bcopy() - that is, hardly ever -
+    was missing a "static" storage class specifier.
+
+ 4. When UTF-8 mode was not set, PCRE looped when compiling certain patterns
+    containing an extended class (one that cannot be represented by a bitmap
+    because it contains high-valued characters or Unicode property items, e.g.
+    [\pZ]). Almost always one would set UTF-8 mode when processing such a
+    pattern, but PCRE should not loop if you do not (it no longer does).
+    [Detail: two cases were found: (a) a repeated subpattern containing an
+    extended class; (b) a recursive reference to a subpattern that followed a
+    previous extended class. It wasn't skipping over the extended class
+    correctly when UTF-8 mode was not set.]
+
+ 5. A negated single-character class was not being recognized as fixed-length
+    in lookbehind assertions such as (?<=[^f]), leading to an incorrect
+    compile error "lookbehind assertion is not fixed length".
+
+ 6. The RunPerlTest auxiliary script was showing an unexpected difference
+    between PCRE and Perl for UTF-8 tests. It turns out that it is hard to
+    write a Perl script that can interpret lines of an input file either as
+    byte characters or as UTF-8, which is what "perltest" was being required to
+    do for the non-UTF-8 and UTF-8 tests, respectively. Essentially what you
+    can't do is switch easily at run time between having the "use utf8;" pragma
+    or not. In the end, I fudged it by using the RunPerlTest script to insert
+    "use utf8;" explicitly for the UTF-8 tests.
+
+ 7. In multiline (/m) mode, PCRE was matching ^ after a terminating newline at
+    the end of the subject string, contrary to the documentation and to what
+    Perl does. This was true of both matching functions. Now it matches only at
+    the start of the subject and immediately after *internal* newlines.
+
+ 8. A call of pcre_fullinfo() from pcretest to get the option bits was passing
+    a pointer to an int instead of a pointer to an unsigned long int. This
+    caused problems on 64-bit systems.
+
+ 9. Applied a patch from the folks at Google to pcrecpp.cc, to fix "another
+    instance of the 'standard' template library not being so standard".
+
+10. There was no check on the number of named subpatterns nor the maximum
+    length of a subpattern name. The product of these values is used to compute
+    the size of the memory block for a compiled pattern. By supplying a very
+    long subpattern name and a large number of named subpatterns, the size
+    computation could be caused to overflow. This is now prevented by limiting
+    the length of names to 32 characters, and the number of named subpatterns
+    to 10,000.
+
+11. Subpatterns that are repeated with specific counts have to be replicated in
+    the compiled pattern. The size of memory for this was computed from the
+    length of the subpattern and the repeat count. The latter is limited to
+    65535, but there was no limit on the former, meaning that integer overflow
+    could in principle occur. The compiled length of a repeated subpattern is
+    now limited to 30,000 bytes in order to prevent this.
+
+12. Added the optional facility to have named substrings with the same name.
+
+13. Added the ability to use a named substring as a condition, using the
+    Python syntax: (?(name)yes|no). This overloads (?(R)... and names that
+    are numbers (not recommended). Forward references are permitted.
+
+14. Added forward references in named backreferences (if you see what I mean).
+
+15. In UTF-8 mode, with the PCRE_DOTALL option set, a quantified dot in the
+    pattern could run off the end of the subject. For example, the pattern
+    "(?s)(.{1,5})"8 did this with the subject "ab".
+
+16. If PCRE_DOTALL or PCRE_MULTILINE were set, pcre_dfa_exec() behaved as if
+    PCRE_CASELESS was set when matching characters that were quantified with ?
+    or *.
+
+17. A character class other than a single negated character that had a minimum
+    but no maximum quantifier - for example [ab]{6,} - was not handled
+    correctly by pce_dfa_exec(). It would match only one character.
+
+18. A valid (though odd) pattern that looked like a POSIX character
+    class but used an invalid character after [ (for example [[,abc,]]) caused
+    pcre_compile() to give the error "Failed: internal error: code overflow" or
+    in some cases to crash with a glibc free() error. This could even happen if
+    the pattern terminated after [[ but there just happened to be a sequence of
+    letters, a binary zero, and a closing ] in the memory that followed.
+
+19. Perl's treatment of octal escapes in the range \400 to \777 has changed
+    over the years. Originally (before any Unicode support), just the bottom 8
+    bits were taken. Thus, for example, \500 really meant \100. Nowadays the
+    output from "man perlunicode" includes this:
+
+      The regular expression compiler produces polymorphic opcodes.  That
+      is, the pattern adapts to the data and automatically switches to
+      the Unicode character scheme when presented with Unicode data--or
+      instead uses a traditional byte scheme when presented with byte
+      data.
+
+    Sadly, a wide octal escape does not cause a switch, and in a string with
+    no other multibyte characters, these octal escapes are treated as before.
+    Thus, in Perl, the pattern  /\500/ actually matches \100 but the pattern
+    /\500|\x{1ff}/ matches \500 or \777 because the whole thing is treated as a
+    Unicode string.
+
+    I have not perpetrated such confusion in PCRE. Up till now, it took just
+    the bottom 8 bits, as in old Perl. I have now made octal escapes with
+    values greater than \377 illegal in non-UTF-8 mode. In UTF-8 mode they
+    translate to the appropriate multibyte character.
+
+29. Applied some refactoring to reduce the number of warnings from Microsoft
+    and Borland compilers. This has included removing the fudge introduced
+    seven years ago for the OS/2 compiler (see 2.02/2 below) because it caused
+    a warning about an unused variable.
+
+21. PCRE has not included VT (character 0x0b) in the set of whitespace
+    characters since release 4.0, because Perl (from release 5.004) does not.
+    [Or at least, is documented not to: some releases seem to be in conflict
+    with the documentation.] However, when a pattern was studied with
+    pcre_study() and all its branches started with \s, PCRE still included VT
+    as a possible starting character. Of course, this did no harm; it just
+    caused an unnecessary match attempt.
+
+22. Removed a now-redundant internal flag bit that recorded the fact that case
+    dependency changed within the pattern. This was once needed for "required
+    byte" processing, but is no longer used. This recovers a now-scarce options
+    bit. Also moved the least significant internal flag bit to the most-
+    significant bit of the word, which was not previously used (hangover from
+    the days when it was an int rather than a uint) to free up another bit for
+    the future.
+
+23. Added support for CRLF line endings as well as CR and LF. As well as the
+    default being selectable at build time, it can now be changed at runtime
+    via the PCRE_NEWLINE_xxx flags. There are now options for pcregrep to
+    specify that it is scanning data with non-default line endings.
+
+24. Changed the definition of CXXLINK to make it agree with the definition of
+    LINK in the Makefile, by replacing LDFLAGS to CXXFLAGS.
+
+25. Applied Ian Taylor's patches to avoid using another stack frame for tail
+    recursions. This makes a big different to stack usage for some patterns.
+
+26. If a subpattern containing a named recursion or subroutine reference such
+    as (?P>B) was quantified, for example (xxx(?P>B)){3}, the calculation of
+    the space required for the compiled pattern went wrong and gave too small a
+    value. Depending on the environment, this could lead to "Failed: internal
+    error: code overflow at offset 49" or "glibc detected double free or
+    corruption" errors.
+
+27. Applied patches from Google (a) to support the new newline modes and (b) to
+    advance over multibyte UTF-8 characters in GlobalReplace.
+
+28. Change free() to pcre_free() in pcredemo.c. Apparently this makes a
+    difference for some implementation of PCRE in some Windows version.
+
+29. Added some extra testing facilities to pcretest:
+
+    \q<number>   in a data line sets the "match limit" value
+    \Q<number>   in a data line sets the "match recursion limt" value
+    -S <number>  sets the stack size, where <number> is in megabytes
+
+    The -S option isn't available for Windows.
+
+
+Version 6.6 06-Feb-06
+---------------------
+
+ 1. Change 16(a) for 6.5 broke things, because PCRE_DATA_SCOPE was not defined
+    in pcreposix.h. I have copied the definition from pcre.h.
+
+ 2. Change 25 for 6.5 broke compilation in a build directory out-of-tree
+    because pcre.h is no longer a built file.
+
+ 3. Added Jeff Friedl's additional debugging patches to pcregrep. These are
+    not normally included in the compiled code.
+
+
+Version 6.5 01-Feb-06
+---------------------
+
+ 1. When using the partial match feature with pcre_dfa_exec(), it was not
+    anchoring the second and subsequent partial matches at the new starting
+    point. This could lead to incorrect results. For example, with the pattern
+    /1234/, partially matching against "123" and then "a4" gave a match.
+
+ 2. Changes to pcregrep:
+
+    (a) All non-match returns from pcre_exec() were being treated as failures
+        to match the line. Now, unless the error is PCRE_ERROR_NOMATCH, an
+        error message is output. Some extra information is given for the
+        PCRE_ERROR_MATCHLIMIT and PCRE_ERROR_RECURSIONLIMIT errors, which are
+        probably the only errors that are likely to be caused by users (by
+        specifying a regex that has nested indefinite repeats, for instance).
+        If there are more than 20 of these errors, pcregrep is abandoned.
+
+    (b) A binary zero was treated as data while matching, but terminated the
+        output line if it was written out. This has been fixed: binary zeroes
+        are now no different to any other data bytes.
+
+    (c) Whichever of the LC_ALL or LC_CTYPE environment variables is set is
+        used to set a locale for matching. The --locale=xxxx long option has
+        been added (no short equivalent) to specify a locale explicitly on the
+        pcregrep command, overriding the environment variables.
+
+    (d) When -B was used with -n, some line numbers in the output were one less
+        than they should have been.
+
+    (e) Added the -o (--only-matching) option.
+
+    (f) If -A or -C was used with -c (count only), some lines of context were
+        accidentally printed for the final match.
+
+    (g) Added the -H (--with-filename) option.
+
+    (h) The combination of options -rh failed to suppress file names for files
+        that were found from directory arguments.
+
+    (i) Added the -D (--devices) and -d (--directories) options.
+
+    (j) Added the -F (--fixed-strings) option.
+
+    (k) Allow "-" to be used as a file name for -f as well as for a data file.
+
+    (l) Added the --colo(u)r option.
+
+    (m) Added Jeffrey Friedl's -S testing option, but within #ifdefs so that it
+        is not present by default.
+
+ 3. A nasty bug was discovered in the handling of recursive patterns, that is,
+    items such as (?R) or (?1), when the recursion could match a number of
+    alternatives. If it matched one of the alternatives, but subsequently,
+    outside the recursion, there was a failure, the code tried to back up into
+    the recursion. However, because of the way PCRE is implemented, this is not
+    possible, and the result was an incorrect result from the match.
+
+    In order to prevent this happening, the specification of recursion has
+    been changed so that all such subpatterns are automatically treated as
+    atomic groups. Thus, for example, (?R) is treated as if it were (?>(?R)).
+
+ 4. I had overlooked the fact that, in some locales, there are characters for
+    which isalpha() is true but neither isupper() nor islower() are true. In
+    the fr_FR locale, for instance, the \xAA and \xBA characters (ordmasculine
+    and ordfeminine) are like this. This affected the treatment of \w and \W
+    when they appeared in character classes, but not when they appeared outside
+    a character class. The bit map for "word" characters is now created
+    separately from the results of isalnum() instead of just taking it from the
+    upper, lower, and digit maps. (Plus the underscore character, of course.)
+
+ 5. The above bug also affected the handling of POSIX character classes such as
+    [[:alpha:]] and [[:alnum:]]. These do not have their own bit maps in PCRE's
+    permanent tables. Instead, the bit maps for such a class were previously
+    created as the appropriate unions of the upper, lower, and digit bitmaps.
+    Now they are created by subtraction from the [[:word:]] class, which has
+    its own bitmap.
+
+ 6. The [[:blank:]] character class matches horizontal, but not vertical space.
+    It is created by subtracting the vertical space characters (\x09, \x0a,
+    \x0b, \x0c) from the [[:space:]] bitmap. Previously, however, the
+    subtraction was done in the overall bitmap for a character class, meaning
+    that a class such as [\x0c[:blank:]] was incorrect because \x0c would not
+    be recognized. This bug has been fixed.
+
+ 7. Patches from the folks at Google:
+
+      (a) pcrecpp.cc: "to handle a corner case that may or may not happen in
+      real life, but is still worth protecting against".
+
+      (b) pcrecpp.cc: "corrects a bug when negative radixes are used with
+      regular expressions".
+
+      (c) pcre_scanner.cc: avoid use of std::count() because not all systems
+      have it.
+
+      (d) Split off pcrecpparg.h from pcrecpp.h and had the former built by
+      "configure" and the latter not, in order to fix a problem somebody had
+      with compiling the Arg class on HP-UX.
+
+      (e) Improve the error-handling of the C++ wrapper a little bit.
+
+      (f) New tests for checking recursion limiting.
+
+ 8. The pcre_memmove() function, which is used only if the environment does not
+    have a standard memmove() function (and is therefore rarely compiled),
+    contained two bugs: (a) use of int instead of size_t, and (b) it was not
+    returning a result (though PCRE never actually uses the result).
+
+ 9. In the POSIX regexec() interface, if nmatch is specified as a ridiculously
+    large number - greater than INT_MAX/(3*sizeof(int)) - REG_ESPACE is
+    returned instead of calling malloc() with an overflowing number that would
+    most likely cause subsequent chaos.
+
+10. The debugging option of pcretest was not showing the NO_AUTO_CAPTURE flag.
+
+11. The POSIX flag REG_NOSUB is now supported. When a pattern that was compiled
+    with this option is matched, the nmatch and pmatch options of regexec() are
+    ignored.
+
+12. Added REG_UTF8 to the POSIX interface. This is not defined by POSIX, but is
+    provided in case anyone wants to the the POSIX interface with UTF-8
+    strings.
+
+13. Added CXXLDFLAGS to the Makefile parameters to provide settings only on the
+    C++ linking (needed for some HP-UX environments).
+
+14. Avoid compiler warnings in get_ucpname() when compiled without UCP support
+    (unused parameter) and in the pcre_printint() function (omitted "default"
+    switch label when the default is to do nothing).
+
+15. Added some code to make it possible, when PCRE is compiled as a C++
+    library, to replace subject pointers for pcre_exec() with a smart pointer
+    class, thus making it possible to process discontinuous strings.
+
+16. The two macros PCRE_EXPORT and PCRE_DATA_SCOPE are confusing, and perform
+    much the same function. They were added by different people who were trying
+    to make PCRE easy to compile on non-Unix systems. It has been suggested
+    that PCRE_EXPORT be abolished now that there is more automatic apparatus
+    for compiling on Windows systems. I have therefore replaced it with
+    PCRE_DATA_SCOPE. This is set automatically for Windows; if not set it
+    defaults to "extern" for C or "extern C" for C++, which works fine on
+    Unix-like systems. It is now possible to override the value of PCRE_DATA_
+    SCOPE with something explicit in config.h. In addition:
+
+    (a) pcreposix.h still had just "extern" instead of either of these macros;
+        I have replaced it with PCRE_DATA_SCOPE.
+
+    (b) Functions such as _pcre_xclass(), which are internal to the library,
+        but external in the C sense, all had PCRE_EXPORT in their definitions.
+        This is apparently wrong for the Windows case, so I have removed it.
+        (It makes no difference on Unix-like systems.)
+
+17. Added a new limit, MATCH_LIMIT_RECURSION, which limits the depth of nesting
+    of recursive calls to match(). This is different to MATCH_LIMIT because
+    that limits the total number of calls to match(), not all of which increase
+    the depth of recursion. Limiting the recursion depth limits the amount of
+    stack (or heap if NO_RECURSE is set) that is used. The default can be set
+    when PCRE is compiled, and changed at run time. A patch from Google adds
+    this functionality to the C++ interface.
+
+18. Changes to the handling of Unicode character properties:
+
+    (a) Updated the table to Unicode 4.1.0.
+
+    (b) Recognize characters that are not in the table as "Cn" (undefined).
+
+    (c) I revised the way the table is implemented to a much improved format
+        which includes recognition of ranges. It now supports the ranges that
+        are defined in UnicodeData.txt, and it also amalgamates other
+        characters into ranges. This has reduced the number of entries in the
+        table from around 16,000 to around 3,000, thus reducing its size
+        considerably. I realized I did not need to use a tree structure after
+        all - a binary chop search is just as efficient. Having reduced the
+        number of entries, I extended their size from 6 bytes to 8 bytes to
+        allow for more data.
+
+    (d) Added support for Unicode script names via properties such as \p{Han}.
+
+19. In UTF-8 mode, a backslash followed by a non-Ascii character was not
+    matching that character.
+
+20. When matching a repeated Unicode property with a minimum greater than zero,
+    (for example \pL{2,}), PCRE could look past the end of the subject if it
+    reached it while seeking the minimum number of characters. This could
+    happen only if some of the characters were more than one byte long, because
+    there is a check for at least the minimum number of bytes.
+
+21. Refactored the implementation of \p and \P so as to be more general, to
+    allow for more different types of property in future. This has changed the
+    compiled form incompatibly. Anybody with saved compiled patterns that use
+    \p or \P will have to recompile them.
+
+22. Added "Any" and "L&" to the supported property types.
+
+23. Recognize \x{...} as a code point specifier, even when not in UTF-8 mode,
+    but give a compile time error if the value is greater than 0xff.
+
+24. The man pages for pcrepartial, pcreprecompile, and pcre_compile2 were
+    accidentally not being installed or uninstalled.
+
+25. The pcre.h file was built from pcre.h.in, but the only changes that were
+    made were to insert the current release number. This seemed silly, because
+    it made things harder for people building PCRE on systems that don't run
+    "configure". I have turned pcre.h into a distributed file, no longer built
+    by "configure", with the version identification directly included. There is
+    no longer a pcre.h.in file.
+
+    However, this change necessitated a change to the pcre-config script as
+    well. It is built from pcre-config.in, and one of the substitutions was the
+    release number. I have updated configure.ac so that ./configure now finds
+    the release number by grepping pcre.h.
+
+26. Added the ability to run the tests under valgrind.
+
+
+Version 6.4 05-Sep-05
+---------------------
+
+ 1. Change 6.0/10/(l) to pcregrep introduced a bug that caused separator lines
+    "--" to be printed when multiple files were scanned, even when none of the
+    -A, -B, or -C options were used. This is not compatible with Gnu grep, so I
+    consider it to be a bug, and have restored the previous behaviour.
+
+ 2. A couple of code tidies to get rid of compiler warnings.
+
+ 3. The pcretest program used to cheat by referring to symbols in the library
+    whose names begin with _pcre_. These are internal symbols that are not
+    really supposed to be visible externally, and in some environments it is
+    possible to suppress them. The cheating is now confined to including
+    certain files from the library's source, which is a bit cleaner.
+
+ 4. Renamed pcre.in as pcre.h.in to go with pcrecpp.h.in; it also makes the
+    file's purpose clearer.
+
+ 5. Reorganized pcre_ucp_findchar().
+
+
+Version 6.3 15-Aug-05
+---------------------
+
+ 1. The file libpcre.pc.in did not have general read permission in the tarball.
+
+ 2. There were some problems when building without C++ support:
+
+    (a) If C++ support was not built, "make install" and "make test" still
+        tried to test it.
+
+    (b) There were problems when the value of CXX was explicitly set. Some
+        changes have been made to try to fix these, and ...
+
+    (c) --disable-cpp can now be used to explicitly disable C++ support.
+
+    (d) The use of @CPP_OBJ@ directly caused a blank line preceded by a
+        backslash in a target when C++ was disabled. This confuses some
+        versions of "make", apparently. Using an intermediate variable solves
+        this. (Same for CPP_LOBJ.)
+
+ 3. $(LINK_FOR_BUILD) now includes $(CFLAGS_FOR_BUILD) and $(LINK)
+    (non-Windows) now includes $(CFLAGS) because these flags are sometimes
+    necessary on certain architectures.
+
+ 4. Added a setting of -export-symbols-regex to the link command to remove
+    those symbols that are exported in the C sense, but actually are local
+    within the library, and not documented. Their names all begin with
+    "_pcre_". This is not a perfect job, because (a) we have to except some
+    symbols that pcretest ("illegally") uses, and (b) the facility isn't always
+    available (and never for static libraries). I have made a note to try to
+    find a way round (a) in the future.
+
+
+Version 6.2 01-Aug-05
+---------------------
+
+ 1. There was no test for integer overflow of quantifier values. A construction
+    such as {1111111111111111} would give undefined results. What is worse, if
+    a minimum quantifier for a parenthesized subpattern overflowed and became
+    negative, the calculation of the memory size went wrong. This could have
+    led to memory overwriting.
+
+ 2. Building PCRE using VPATH was broken. Hopefully it is now fixed.
+
+ 3. Added "b" to the 2nd argument of fopen() in dftables.c, for non-Unix-like
+    operating environments where this matters.
+
+ 4. Applied Giuseppe Maxia's patch to add additional features for controlling
+    PCRE options from within the C++ wrapper.
+
+ 5. Named capturing subpatterns were not being correctly counted when a pattern
+    was compiled. This caused two problems: (a) If there were more than 100
+    such subpatterns, the calculation of the memory needed for the whole
+    compiled pattern went wrong, leading to an overflow error. (b) Numerical
+    back references of the form \12, where the number was greater than 9, were
+    not recognized as back references, even though there were sufficient
+    previous subpatterns.
+
+ 6. Two minor patches to pcrecpp.cc in order to allow it to compile on older
+    versions of gcc, e.g. 2.95.4.
+
+
+Version 6.1 21-Jun-05
+---------------------
+
+ 1. There was one reference to the variable "posix" in pcretest.c that was not
+    surrounded by "#if !defined NOPOSIX".
+
+ 2. Make it possible to compile pcretest without DFA support, UTF8 support, or
+    the cross-check on the old pcre_info() function, for the benefit of the
+    cut-down version of PCRE that is currently imported into Exim.
+
+ 3. A (silly) pattern starting with (?i)(?-i) caused an internal space
+    allocation error. I've done the easy fix, which wastes 2 bytes for sensible
+    patterns that start (?i) but I don't think that matters. The use of (?i) is
+    just an example; this all applies to the other options as well.
+
+ 4. Since libtool seems to echo the compile commands it is issuing, the output
+    from "make" can be reduced a bit by putting "@" in front of each libtool
+    compile command.
+
+ 5. Patch from the folks at Google for configure.in to be a bit more thorough
+    in checking for a suitable C++ installation before trying to compile the
+    C++ stuff. This should fix a reported problem when a compiler was present,
+    but no suitable headers.
+
+ 6. The man pages all had just "PCRE" as their title. I have changed them to
+    be the relevant file name. I have also arranged that these names are
+    retained in the file doc/pcre.txt, which is a concatenation in text format
+    of all the man pages except the little individual ones for each function.
+
+ 7. The NON-UNIX-USE file had not been updated for the different set of source
+    files that come with release 6. I also added a few comments about the C++
+    wrapper.
+
+
+Version 6.0 07-Jun-05
+---------------------
+
+ 1. Some minor internal re-organization to help with my DFA experiments.
+
+ 2. Some missing #ifdef SUPPORT_UCP conditionals in pcretest and printint that
+    didn't matter for the library itself when fully configured, but did matter
+    when compiling without UCP support, or within Exim, where the ucp files are
+    not imported.
+
+ 3. Refactoring of the library code to split up the various functions into
+    different source modules. The addition of the new DFA matching code (see
+    below) to a single monolithic source would have made it really too
+    unwieldy, quite apart from causing all the code to be include in a
+    statically linked application, when only some functions are used. This is
+    relevant even without the DFA addition now that patterns can be compiled in
+    one application and matched in another.
+
+    The downside of splitting up is that there have to be some external
+    functions and data tables that are used internally in different modules of
+    the library but which are not part of the API. These have all had their
+    names changed to start with "_pcre_" so that they are unlikely to clash
+    with other external names.
+
+ 4. Added an alternate matching function, pcre_dfa_exec(), which matches using
+    a different (DFA) algorithm. Although it is slower than the original
+    function, it does have some advantages for certain types of matching
+    problem.
+
+ 5. Upgrades to pcretest in order to test the features of pcre_dfa_exec(),
+    including restarting after a partial match.
+
+ 6. A patch for pcregrep that defines INVALID_FILE_ATTRIBUTES if it is not
+    defined when compiling for Windows was sent to me. I have put it into the
+    code, though I have no means of testing or verifying it.
+
+ 7. Added the pcre_refcount() auxiliary function.
+
+ 8. Added the PCRE_FIRSTLINE option. This constrains an unanchored pattern to
+    match before or at the first newline in the subject string. In pcretest,
+    the /f option on a pattern can be used to set this.
+
+ 9. A repeated \w when used in UTF-8 mode with characters greater than 256
+    would behave wrongly. This has been present in PCRE since release 4.0.
+
+10. A number of changes to the pcregrep command:
+
+    (a) Refactored how -x works; insert ^(...)$ instead of setting
+        PCRE_ANCHORED and checking the length, in preparation for adding
+        something similar for -w.
+
+    (b) Added the -w (match as a word) option.
+
+    (c) Refactored the way lines are read and buffered so as to have more
+        than one at a time available.
+
+    (d) Implemented a pcregrep test script.
+
+    (e) Added the -M (multiline match) option. This allows patterns to match
+        over several lines of the subject. The buffering ensures that at least
+        8K, or the rest of the document (whichever is the shorter) is available
+        for matching (and similarly the previous 8K for lookbehind assertions).
+
+    (f) Changed the --help output so that it now says
+
+          -w, --word-regex(p)
+
+        instead of two lines, one with "regex" and the other with "regexp"
+        because that confused at least one person since the short forms are the
+        same. (This required a bit of code, as the output is generated
+        automatically from a table. It wasn't just a text change.)
+
+    (g) -- can be used to terminate pcregrep options if the next thing isn't an
+        option but starts with a hyphen. Could be a pattern or a path name
+        starting with a hyphen, for instance.
+
+    (h) "-" can be given as a file name to represent stdin.
+
+    (i) When file names are being printed, "(standard input)" is used for
+        the standard input, for compatibility with GNU grep. Previously
+        "<stdin>" was used.
+
+    (j) The option --label=xxx can be used to supply a name to be used for
+        stdin when file names are being printed. There is no short form.
+
+    (k) Re-factored the options decoding logic because we are going to add
+        two more options that take data. Such options can now be given in four
+        different ways, e.g. "-fname", "-f name", "--file=name", "--file name".
+
+    (l) Added the -A, -B, and -C options for requesting that lines of context
+        around matches be printed.
+
+    (m) Added the -L option to print the names of files that do not contain
+        any matching lines, that is, the complement of -l.
+
+    (n) The return code is 2 if any file cannot be opened, but pcregrep does
+        continue to scan other files.
+
+    (o) The -s option was incorrectly implemented. For compatibility with other
+        greps, it now suppresses the error message for a non-existent or non-
+        accessible file (but not the return code). There is a new option called
+        -q that suppresses the output of matching lines, which was what -s was
+        previously doing.
+
+    (p) Added --include and --exclude options to specify files for inclusion
+        and exclusion when recursing.
+
+11. The Makefile was not using the Autoconf-supported LDFLAGS macro properly.
+    Hopefully, it now does.
+
+12. Missing cast in pcre_study().
+
+13. Added an "uninstall" target to the makefile.
+
+14. Replaced "extern" in the function prototypes in Makefile.in with
+    "PCRE_DATA_SCOPE", which defaults to 'extern' or 'extern "C"' in the Unix
+    world, but is set differently for Windows.
+
+15. Added a second compiling function called pcre_compile2(). The only
+    difference is that it has an extra argument, which is a pointer to an
+    integer error code. When there is a compile-time failure, this is set
+    non-zero, in addition to the error test pointer being set to point to an
+    error message. The new argument may be NULL if no error number is required
+    (but then you may as well call pcre_compile(), which is now just a
+    wrapper). This facility is provided because some applications need a
+    numeric error indication, but it has also enabled me to tidy up the way
+    compile-time errors are handled in the POSIX wrapper.
+
+16. Added VPATH=.libs to the makefile; this should help when building with one
+    prefix path and installing with another. (Or so I'm told by someone who
+    knows more about this stuff than I do.)
+
+17. Added a new option, REG_DOTALL, to the POSIX function regcomp(). This
+    passes PCRE_DOTALL to the pcre_compile() function, making the "." character
+    match everything, including newlines. This is not POSIX-compatible, but
+    somebody wanted the feature. From pcretest it can be activated by using
+    both the P and the s flags.
+
+18. AC_PROG_LIBTOOL appeared twice in Makefile.in. Removed one.
+
+19. libpcre.pc was being incorrectly installed as executable.
+
+20. A couple of places in pcretest check for end-of-line by looking for '\n';
+    it now also looks for '\r' so that it will work unmodified on Windows.
+
+21. Added Google's contributed C++ wrapper to the distribution.
+
+22. Added some untidy missing memory free() calls in pcretest, to keep
+    Electric Fence happy when testing.
+
+
+
+Version 5.0 13-Sep-04
+---------------------
+
+ 1. Internal change: literal characters are no longer packed up into items
+    containing multiple characters in a single byte-string. Each character
+    is now matched using a separate opcode. However, there may be more than one
+    byte in the character in UTF-8 mode.
+
+ 2. The pcre_callout_block structure has two new fields: pattern_position and
+    next_item_length. These contain the offset in the pattern to the next match
+    item, and its length, respectively.
+
+ 3. The PCRE_AUTO_CALLOUT option for pcre_compile() requests the automatic
+    insertion of callouts before each pattern item. Added the /C option to
+    pcretest to make use of this.
+
+ 4. On the advice of a Windows user, the lines
+
+      #if defined(_WIN32) || defined(WIN32)
+      _setmode( _fileno( stdout ), 0x8000 );
+      #endif  /* defined(_WIN32) || defined(WIN32) */
+
+    have been added to the source of pcretest. This apparently does useful
+    magic in relation to line terminators.
+
+ 5. Changed "r" and "w" in the calls to fopen() in pcretest to "rb" and "wb"
+    for the benefit of those environments where the "b" makes a difference.
+
+ 6. The icc compiler has the same options as gcc, but "configure" doesn't seem
+    to know about it. I have put a hack into configure.in that adds in code
+    to set GCC=yes if CC=icc. This seems to end up at a point in the
+    generated configure script that is early enough to affect the setting of
+    compiler options, which is what is needed, but I have no means of testing
+    whether it really works. (The user who reported this had patched the
+    generated configure script, which of course I cannot do.)
+
+    LATER: After change 22 below (new libtool files), the configure script
+    seems to know about icc (and also ecc). Therefore, I have commented out
+    this hack in configure.in.
+
+ 7. Added support for pkg-config (2 patches were sent in).
+
+ 8. Negated POSIX character classes that used a combination of internal tables
+    were completely broken. These were [[:^alpha:]], [[:^alnum:]], and
+    [[:^ascii]]. Typically, they would match almost any characters. The other
+    POSIX classes were not broken in this way.
+
+ 9. Matching the pattern "\b.*?" against "ab cd", starting at offset 1, failed
+    to find the match, as PCRE was deluded into thinking that the match had to
+    start at the start point or following a newline. The same bug applied to
+    patterns with negative forward assertions or any backward assertions
+    preceding ".*" at the start, unless the pattern required a fixed first
+    character. This was a failing pattern: "(?!.bcd).*". The bug is now fixed.
+
+10. In UTF-8 mode, when moving forwards in the subject after a failed match
+    starting at the last subject character, bytes beyond the end of the subject
+    string were read.
+
+11. Renamed the variable "class" as "classbits" to make life easier for C++
+    users. (Previously there was a macro definition, but it apparently wasn't
+    enough.)
+
+12. Added the new field "tables" to the extra data so that tables can be passed
+    in at exec time, or the internal tables can be re-selected. This allows
+    a compiled regex to be saved and re-used at a later time by a different
+    program that might have everything at different addresses.
+
+13. Modified the pcre-config script so that, when run on Solaris, it shows a
+    -R library as well as a -L library.
+
+14. The debugging options of pcretest (-d on the command line or D on a
+    pattern) showed incorrect output for anything following an extended class
+    that contained multibyte characters and which was followed by a quantifier.
+
+15. Added optional support for general category Unicode character properties
+    via the \p, \P, and \X escapes. Unicode property support implies UTF-8
+    support. It adds about 90K to the size of the library. The meanings of the
+    inbuilt class escapes such as \d and \s have NOT been changed.
+
+16. Updated pcredemo.c to include calls to free() to release the memory for the
+    compiled pattern.
+
+17. The generated file chartables.c was being created in the source directory
+    instead of in the building directory. This caused the build to fail if the
+    source directory was different from the building directory, and was
+    read-only.
+
+18. Added some sample Win commands from Mark Tetrode into the NON-UNIX-USE
+    file. No doubt somebody will tell me if they don't make sense... Also added
+    Dan Mooney's comments about building on OpenVMS.
+
+19. Added support for partial matching via the PCRE_PARTIAL option for
+    pcre_exec() and the \P data escape in pcretest.
+
+20. Extended pcretest with 3 new pattern features:
+
+    (i)   A pattern option of the form ">rest-of-line" causes pcretest to
+          write the compiled pattern to the file whose name is "rest-of-line".
+          This is a straight binary dump of the data, with the saved pointer to
+          the character tables forced to be NULL. The study data, if any, is
+          written too. After writing, pcretest reads a new pattern.
+
+    (ii)  If, instead of a pattern, "<rest-of-line" is given, pcretest reads a
+          compiled pattern from the given file. There must not be any
+          occurrences of "<" in the file name (pretty unlikely); if there are,
+          pcretest will instead treat the initial "<" as a pattern delimiter.
+          After reading in the pattern, pcretest goes on to read data lines as
+          usual.
+
+    (iii) The F pattern option causes pcretest to flip the bytes in the 32-bit
+          and 16-bit fields in a compiled pattern, to simulate a pattern that
+          was compiled on a host of opposite endianness.
+
+21. The pcre-exec() function can now cope with patterns that were compiled on
+    hosts of opposite endianness, with this restriction:
+
+      As for any compiled expression that is saved and used later, the tables
+      pointer field cannot be preserved; the extra_data field in the arguments
+      to pcre_exec() should be used to pass in a tables address if a value
+      other than the default internal tables were used at compile time.
+
+22. Calling pcre_exec() with a negative value of the "ovecsize" parameter is
+    now diagnosed as an error. Previously, most of the time, a negative number
+    would have been treated as zero, but if in addition "ovector" was passed as
+    NULL, a crash could occur.
+
+23. Updated the files ltmain.sh, config.sub, config.guess, and aclocal.m4 with
+    new versions from the libtool 1.5 distribution (the last one is a copy of
+    a file called libtool.m4). This seems to have fixed the need to patch
+    "configure" to support Darwin 1.3 (which I used to do). However, I still
+    had to patch ltmain.sh to ensure that ${SED} is set (it isn't on my
+    workstation).
+
+24. Changed the PCRE licence to be the more standard "BSD" licence.
+
+
+Version 4.5 01-Dec-03
+---------------------
+
+ 1. There has been some re-arrangement of the code for the match() function so
+    that it can be compiled in a version that does not call itself recursively.
+    Instead, it keeps those local variables that need separate instances for
+    each "recursion" in a frame on the heap, and gets/frees frames whenever it
+    needs to "recurse". Keeping track of where control must go is done by means
+    of setjmp/longjmp. The whole thing is implemented by a set of macros that
+    hide most of the details from the main code, and operates only if
+    NO_RECURSE is defined while compiling pcre.c. If PCRE is built using the
+    "configure" mechanism, "--disable-stack-for-recursion" turns on this way of
+    operating.
+
+    To make it easier for callers to provide specially tailored get/free
+    functions for this usage, two new functions, pcre_stack_malloc, and
+    pcre_stack_free, are used. They are always called in strict stacking order,
+    and the size of block requested is always the same.
+
+    The PCRE_CONFIG_STACKRECURSE info parameter can be used to find out whether
+    PCRE has been compiled to use the stack or the heap for recursion. The
+    -C option of pcretest uses this to show which version is compiled.
+
+    A new data escape \S, is added to pcretest; it causes the amounts of store
+    obtained and freed by both kinds of malloc/free at match time to be added
+    to the output.
+
+ 2. Changed the locale test to use "fr_FR" instead of "fr" because that's
+    what's available on my current Linux desktop machine.
+
+ 3. When matching a UTF-8 string, the test for a valid string at the start has
+    been extended. If start_offset is not zero, PCRE now checks that it points
+    to a byte that is the start of a UTF-8 character. If not, it returns
+    PCRE_ERROR_BADUTF8_OFFSET (-11). Note: the whole string is still checked;
+    this is necessary because there may be backward assertions in the pattern.
+    When matching the same subject several times, it may save resources to use
+    PCRE_NO_UTF8_CHECK on all but the first call if the string is long.
+
+ 4. The code for checking the validity of UTF-8 strings has been tightened so
+    that it rejects (a) strings containing 0xfe or 0xff bytes and (b) strings
+    containing "overlong sequences".
+
+ 5. Fixed a bug (appearing twice) that I could not find any way of exploiting!
+    I had written "if ((digitab[*p++] && chtab_digit) == 0)" where the "&&"
+    should have been "&", but it just so happened that all the cases this let
+    through by mistake were picked up later in the function.
+
+ 6. I had used a variable called "isblank" - this is a C99 function, causing
+    some compilers to warn. To avoid this, I renamed it (as "blankclass").
+
+ 7. Cosmetic: (a) only output another newline at the end of pcretest if it is
+    prompting; (b) run "./pcretest /dev/null" at the start of the test script
+    so the version is shown; (c) stop "make test" echoing "./RunTest".
+
+ 8. Added patches from David Burgess to enable PCRE to run on EBCDIC systems.
+
+ 9. The prototype for memmove() for systems that don't have it was using
+    size_t, but the inclusion of the header that defines size_t was later. I've
+    moved the #includes for the C headers earlier to avoid this.
+
+10. Added some adjustments to the code to make it easier to compiler on certain
+    special systems:
+
+      (a) Some "const" qualifiers were missing.
+      (b) Added the macro EXPORT before all exported functions; by default this
+          is defined to be empty.
+      (c) Changed the dftables auxiliary program (that builds chartables.c) so
+          that it reads its output file name as an argument instead of writing
+          to the standard output and assuming this can be redirected.
+
+11. In UTF-8 mode, if a recursive reference (e.g. (?1)) followed a character
+    class containing characters with values greater than 255, PCRE compilation
+    went into a loop.
+
+12. A recursive reference to a subpattern that was within another subpattern
+    that had a minimum quantifier of zero caused PCRE to crash. For example,
+    (x(y(?2))z)? provoked this bug with a subject that got as far as the
+    recursion. If the recursively-called subpattern itself had a zero repeat,
+    that was OK.
+
+13. In pcretest, the buffer for reading a data line was set at 30K, but the
+    buffer into which it was copied (for escape processing) was still set at
+    1024, so long lines caused crashes.
+
+14. A pattern such as /[ab]{1,3}+/ failed to compile, giving the error
+    "internal error: code overflow...". This applied to any character class
+    that was followed by a possessive quantifier.
+
+15. Modified the Makefile to add libpcre.la as a prerequisite for
+    libpcreposix.la because I was told this is needed for a parallel build to
+    work.
+
+16. If a pattern that contained .* following optional items at the start was
+    studied, the wrong optimizing data was generated, leading to matching
+    errors. For example, studying /[ab]*.*c/ concluded, erroneously, that any
+    matching string must start with a or b or c. The correct conclusion for
+    this pattern is that a match can start with any character.
+
+
+Version 4.4 13-Aug-03
+---------------------
+
+ 1. In UTF-8 mode, a character class containing characters with values between
+    127 and 255 was not handled correctly if the compiled pattern was studied.
+    In fixing this, I have also improved the studying algorithm for such
+    classes (slightly).
+
+ 2. Three internal functions had redundant arguments passed to them. Removal
+    might give a very teeny performance improvement.
+
+ 3. Documentation bug: the value of the capture_top field in a callout is *one
+    more than* the number of the hightest numbered captured substring.
+
+ 4. The Makefile linked pcretest and pcregrep with -lpcre, which could result
+    in incorrectly linking with a previously installed version. They now link
+    explicitly with libpcre.la.
+
+ 5. configure.in no longer needs to recognize Cygwin specially.
+
+ 6. A problem in pcre.in for Windows platforms is fixed.
+
+ 7. If a pattern was successfully studied, and the -d (or /D) flag was given to
+    pcretest, it used to include the size of the study block as part of its
+    output. Unfortunately, the structure contains a field that has a different
+    size on different hardware architectures. This meant that the tests that
+    showed this size failed. As the block is currently always of a fixed size,
+    this information isn't actually particularly useful in pcretest output, so
+    I have just removed it.
+
+ 8. Three pre-processor statements accidentally did not start in column 1.
+    Sadly, there are *still* compilers around that complain, even though
+    standard C has not required this for well over a decade. Sigh.
+
+ 9. In pcretest, the code for checking callouts passed small integers in the
+    callout_data field, which is a void * field. However, some picky compilers
+    complained about the casts involved for this on 64-bit systems. Now
+    pcretest passes the address of the small integer instead, which should get
+    rid of the warnings.
+
+10. By default, when in UTF-8 mode, PCRE now checks for valid UTF-8 strings at
+    both compile and run time, and gives an error if an invalid UTF-8 sequence
+    is found. There is a option for disabling this check in cases where the
+    string is known to be correct and/or the maximum performance is wanted.
+
+11. In response to a bug report, I changed one line in Makefile.in from
+
+        -Wl,--out-implib,.libs/lib@WIN_PREFIX@pcreposix.dll.a \
+    to
+        -Wl,--out-implib,.libs/@WIN_PREFIX@libpcreposix.dll.a \
+
+    to look similar to other lines, but I have no way of telling whether this
+    is the right thing to do, as I do not use Windows. No doubt I'll get told
+    if it's wrong...
+
+
+Version 4.3 21-May-03
+---------------------
+
+1. Two instances of @WIN_PREFIX@ omitted from the Windows targets in the
+   Makefile.
+
+2. Some refactoring to improve the quality of the code:
+
+   (i)   The utf8_table... variables are now declared "const".
+
+   (ii)  The code for \cx, which used the "case flipping" table to upper case
+         lower case letters, now just substracts 32. This is ASCII-specific,
+         but the whole concept of \cx is ASCII-specific, so it seems
+         reasonable.
+
+   (iii) PCRE was using its character types table to recognize decimal and
+         hexadecimal digits in the pattern. This is silly, because it handles
+         only 0-9, a-f, and A-F, but the character types table is locale-
+         specific, which means strange things might happen. A private
+         table is now used for this - though it costs 256 bytes, a table is
+         much faster than multiple explicit tests. Of course, the standard
+         character types table is still used for matching digits in subject
+         strings against \d.
+
+   (iv)  Strictly, the identifier ESC_t is reserved by POSIX (all identifiers
+         ending in _t are). So I've renamed it as ESC_tee.
+
+3. The first argument for regexec() in the POSIX wrapper should have been
+   defined as "const".
+
+4. Changed pcretest to use malloc() for its buffers so that they can be
+   Electric Fenced for debugging.
+
+5. There were several places in the code where, in UTF-8 mode, PCRE would try
+   to read one or more bytes before the start of the subject string. Often this
+   had no effect on PCRE's behaviour, but in some circumstances it could
+   provoke a segmentation fault.
+
+6. A lookbehind at the start of a pattern in UTF-8 mode could also cause PCRE
+   to try to read one or more bytes before the start of the subject string.
+
+7. A lookbehind in a pattern matched in non-UTF-8 mode on a PCRE compiled with
+   UTF-8 support could misbehave in various ways if the subject string
+   contained bytes with the 0x80 bit set and the 0x40 bit unset in a lookbehind
+   area. (PCRE was not checking for the UTF-8 mode flag, and trying to move
+   back over UTF-8 characters.)
+
+
+Version 4.2 14-Apr-03
+---------------------
+
+1. Typo "#if SUPPORT_UTF8" instead of "#ifdef SUPPORT_UTF8" fixed.
+
+2. Changes to the building process, supplied by Ronald Landheer-Cieslak
+     [ON_WINDOWS]: new variable, "#" on non-Windows platforms
+     [NOT_ON_WINDOWS]: new variable, "#" on Windows platforms
+     [WIN_PREFIX]: new variable, "cyg" for Cygwin
+     * Makefile.in: use autoconf substitution for OBJEXT, EXEEXT, BUILD_OBJEXT
+       and BUILD_EXEEXT
+     Note: automatic setting of the BUILD variables is not yet working
+     set CPPFLAGS and BUILD_CPPFLAGS (but don't use yet) - should be used at
+       compile-time but not at link-time
+     [LINK]: use for linking executables only
+     make different versions for Windows and non-Windows
+     [LINKLIB]: new variable, copy of UNIX-style LINK, used for linking
+       libraries
+     [LINK_FOR_BUILD]: new variable
+     [OBJEXT]: use throughout
+     [EXEEXT]: use throughout
+     <winshared>: new target
+     <wininstall>: new target
+     <dftables.o>: use native compiler
+     <dftables>: use native linker
+     <install>: handle Windows platform correctly
+     <clean>: ditto
+     <check>: ditto
+     copy DLL to top builddir before testing
+
+   As part of these changes, -no-undefined was removed again. This was reported
+   to give trouble on HP-UX 11.0, so getting rid of it seems like a good idea
+   in any case.
+
+3. Some tidies to get rid of compiler warnings:
+
+   . In the match_data structure, match_limit was an unsigned long int, whereas
+     match_call_count was an int. I've made them both unsigned long ints.
+
+   . In pcretest the fact that a const uschar * doesn't automatically cast to
+     a void * provoked a warning.
+
+   . Turning on some more compiler warnings threw up some "shadow" variables
+     and a few more missing casts.
+
+4. If PCRE was complied with UTF-8 support, but called without the PCRE_UTF8
+   option, a class that contained a single character with a value between 128
+   and 255 (e.g. /[\xFF]/) caused PCRE to crash.
+
+5. If PCRE was compiled with UTF-8 support, but called without the PCRE_UTF8
+   option, a class that contained several characters, but with at least one
+   whose value was between 128 and 255 caused PCRE to crash.
+
+
+Version 4.1 12-Mar-03
+---------------------
+
+1. Compiling with gcc -pedantic found a couple of places where casts were
+needed, and a string in dftables.c that was longer than standard compilers are
+required to support.
+
+2. Compiling with Sun's compiler found a few more places where the code could
+be tidied up in order to avoid warnings.
+
+3. The variables for cross-compiling were called HOST_CC and HOST_CFLAGS; the
+first of these names is deprecated in the latest Autoconf in favour of the name
+CC_FOR_BUILD, because "host" is typically used to mean the system on which the
+compiled code will be run. I can't find a reference for HOST_CFLAGS, but by
+analogy I have changed it to CFLAGS_FOR_BUILD.
+
+4. Added -no-undefined to the linking command in the Makefile, because this is
+apparently helpful for Windows. To make it work, also added "-L. -lpcre" to the
+linking step for the pcreposix library.
+
+5. PCRE was failing to diagnose the case of two named groups with the same
+name.
+
+6. A problem with one of PCRE's optimizations was discovered. PCRE remembers a
+literal character that is needed in the subject for a match, and scans along to
+ensure that it is present before embarking on the full matching process. This
+saves time in cases of nested unlimited repeats that are never going to match.
+Problem: the scan can take a lot of time if the subject is very long (e.g.
+megabytes), thus penalizing straightforward matches. It is now done only if the
+amount of subject to be scanned is less than 1000 bytes.
+
+7. A lesser problem with the same optimization is that it was recording the
+first character of an anchored pattern as "needed", thus provoking a search
+right along the subject, even when the first match of the pattern was going to
+fail. The "needed" character is now not set for anchored patterns, unless it
+follows something in the pattern that is of non-fixed length. Thus, it still
+fulfils its original purpose of finding quick non-matches in cases of nested
+unlimited repeats, but isn't used for simple anchored patterns such as /^abc/.
+
+
+Version 4.0 17-Feb-03
+---------------------
+
+1. If a comment in an extended regex that started immediately after a meta-item
+extended to the end of string, PCRE compiled incorrect data. This could lead to
+all kinds of weird effects. Example: /#/ was bad; /()#/ was bad; /a#/ was not.
+
+2. Moved to autoconf 2.53 and libtool 1.4.2.
+
+3. Perl 5.8 no longer needs "use utf8" for doing UTF-8 things. Consequently,
+the special perltest8 script is no longer needed - all the tests can be run
+from a single perltest script.
+
+4. From 5.004, Perl has not included the VT character (0x0b) in the set defined
+by \s. It has now been removed in PCRE. This means it isn't recognized as
+whitespace in /x regexes too, which is the same as Perl. Note that the POSIX
+class [:space:] *does* include VT, thereby creating a mess.
+
+5. Added the class [:blank:] (a GNU extension from Perl 5.8) to match only
+space and tab.
+
+6. Perl 5.005 was a long time ago. It's time to amalgamate the tests that use
+its new features into the main test script, reducing the number of scripts.
+
+7. Perl 5.8 has changed the meaning of patterns like /a(?i)b/. Earlier versions
+were backward compatible, and made the (?i) apply to the whole pattern, as if
+/i were given. Now it behaves more logically, and applies the option setting
+only to what follows. PCRE has been changed to follow suit. However, if it
+finds options settings right at the start of the pattern, it extracts them into
+the global options, as before. Thus, they show up in the info data.
+
+8. Added support for the \Q...\E escape sequence. Characters in between are
+treated as literals. This is slightly different from Perl in that $ and @ are
+also handled as literals inside the quotes. In Perl, they will cause variable
+interpolation. Note the following examples:
+
+    Pattern            PCRE matches      Perl matches
+
+    \Qabc$xyz\E        abc$xyz           abc followed by the contents of $xyz
+    \Qabc\$xyz\E       abc\$xyz          abc\$xyz
+    \Qabc\E\$\Qxyz\E   abc$xyz           abc$xyz
+
+For compatibility with Perl, \Q...\E sequences are recognized inside character
+classes as well as outside them.
+
+9. Re-organized 3 code statements in pcretest to avoid "overflow in
+floating-point constant arithmetic" warnings from a Microsoft compiler. Added a
+(size_t) cast to one statement in pcretest and one in pcreposix to avoid
+signed/unsigned warnings.
+
+10. SunOS4 doesn't have strtoul(). This was used only for unpicking the -o
+option for pcretest, so I've replaced it by a simple function that does just
+that job.
+
+11. pcregrep was ending with code 0 instead of 2 for the commands "pcregrep" or
+"pcregrep -".
+
+12. Added "possessive quantifiers" ?+, *+, ++, and {,}+ which come from Sun's
+Java package. This provides some syntactic sugar for simple cases of what my
+documentation calls "once-only subpatterns". A pattern such as x*+ is the same
+as (?>x*). In other words, if what is inside (?>...) is just a single repeated
+item, you can use this simplified notation. Note that only makes sense with
+greedy quantifiers. Consequently, the use of the possessive quantifier forces
+greediness, whatever the setting of the PCRE_UNGREEDY option.
+
+13. A change of greediness default within a pattern was not taking effect at
+the current level for patterns like /(b+(?U)a+)/. It did apply to parenthesized
+subpatterns that followed. Patterns like /b+(?U)a+/ worked because the option
+was abstracted outside.
+
+14. PCRE now supports the \G assertion. It is true when the current matching
+position is at the start point of the match. This differs from \A when the
+starting offset is non-zero. Used with the /g option of pcretest (or similar
+code), it works in the same way as it does for Perl's /g option. If all
+alternatives of a regex begin with \G, the expression is anchored to the start
+match position, and the "anchored" flag is set in the compiled expression.
+
+15. Some bugs concerning the handling of certain option changes within patterns
+have been fixed. These applied to options other than (?ims). For example,
+"a(?x: b c )d" did not match "XabcdY" but did match "Xa b c dY". It should have
+been the other way round. Some of this was related to change 7 above.
+
+16. PCRE now gives errors for /[.x.]/ and /[=x=]/ as unsupported POSIX
+features, as Perl does. Previously, PCRE gave the warnings only for /[[.x.]]/
+and /[[=x=]]/. PCRE now also gives an error for /[:name:]/ because it supports
+POSIX classes only within a class (e.g. /[[:alpha:]]/).
+
+17. Added support for Perl's \C escape. This matches one byte, even in UTF8
+mode. Unlike ".", it always matches newline, whatever the setting of
+PCRE_DOTALL. However, PCRE does not permit \C to appear in lookbehind
+assertions. Perl allows it, but it doesn't (in general) work because it can't
+calculate the length of the lookbehind. At least, that's the case for Perl
+5.8.0 - I've been told they are going to document that it doesn't work in
+future.
+
+18. Added an error diagnosis for escapes that PCRE does not support: these are
+\L, \l, \N, \P, \p, \U, \u, and \X.
+
+19. Although correctly diagnosing a missing ']' in a character class, PCRE was
+reading past the end of the pattern in cases such as /[abcd/.
+
+20. PCRE was getting more memory than necessary for patterns with classes that
+contained both POSIX named classes and other characters, e.g. /[[:space:]abc/.
+
+21. Added some code, conditional on #ifdef VPCOMPAT, to make life easier for
+compiling PCRE for use with Virtual Pascal.
+
+22. Small fix to the Makefile to make it work properly if the build is done
+outside the source tree.
+
+23. Added a new extension: a condition to go with recursion. If a conditional
+subpattern starts with (?(R) the "true" branch is used if recursion has
+happened, whereas the "false" branch is used only at the top level.
+
+24. When there was a very long string of literal characters (over 255 bytes
+without UTF support, over 250 bytes with UTF support), the computation of how
+much memory was required could be incorrect, leading to segfaults or other
+strange effects.
+
+25. PCRE was incorrectly assuming anchoring (either to start of subject or to
+start of line for a non-DOTALL pattern) when a pattern started with (.*) and
+there was a subsequent back reference to those brackets. This meant that, for
+example, /(.*)\d+\1/ failed to match "abc123bc". Unfortunately, it isn't
+possible to check for precisely this case. All we can do is abandon the
+optimization if .* occurs inside capturing brackets when there are any back
+references whatsoever. (See below for a better fix that came later.)
+
+26. The handling of the optimization for finding the first character of a
+non-anchored pattern, and for finding a character that is required later in the
+match were failing in some cases. This didn't break the matching; it just
+failed to optimize when it could. The way this is done has been re-implemented.
+
+27. Fixed typo in error message for invalid (?R item (it said "(?p").
+
+28. Added a new feature that provides some of the functionality that Perl
+provides with (?{...}). The facility is termed a "callout". The way it is done
+in PCRE is for the caller to provide an optional function, by setting
+pcre_callout to its entry point. Like pcre_malloc and pcre_free, this is a
+global variable. By default it is unset, which disables all calling out. To get
+the function called, the regex must include (?C) at appropriate points. This
+is, in fact, equivalent to (?C0), and any number <= 255 may be given with (?C).
+This provides a means of identifying different callout points. When PCRE
+reaches such a point in the regex, if pcre_callout has been set, the external
+function is called. It is provided with data in a structure called
+pcre_callout_block, which is defined in pcre.h. If the function returns 0,
+matching continues; if it returns a non-zero value, the match at the current
+point fails. However, backtracking will occur if possible. [This was changed
+later and other features added - see item 49 below.]
+
+29. pcretest is upgraded to test the callout functionality. It provides a
+callout function that displays information. By default, it shows the start of
+the match and the current position in the text. There are some new data escapes
+to vary what happens:
+
+    \C+         in addition, show current contents of captured substrings
+    \C-         do not supply a callout function
+    \C!n        return 1 when callout number n is reached
+    \C!n!m      return 1 when callout number n is reached for the mth time
+
+30. If pcregrep was called with the -l option and just a single file name, it
+output "<stdin>" if a match was found, instead of the file name.
+
+31. Improve the efficiency of the POSIX API to PCRE. If the number of capturing
+slots is less than POSIX_MALLOC_THRESHOLD, use a block on the stack to pass to
+pcre_exec(). This saves a malloc/free per call. The default value of
+POSIX_MALLOC_THRESHOLD is 10; it can be changed by --with-posix-malloc-threshold
+when configuring.
+
+32. The default maximum size of a compiled pattern is 64K. There have been a
+few cases of people hitting this limit. The code now uses macros to handle the
+storing of links as offsets within the compiled pattern. It defaults to 2-byte
+links, but this can be changed to 3 or 4 bytes by --with-link-size when
+configuring. Tests 2 and 5 work only with 2-byte links because they output
+debugging information about compiled patterns.
+
+33. Internal code re-arrangements:
+
+(a) Moved the debugging function for printing out a compiled regex into
+    its own source file (printint.c) and used #include to pull it into
+    pcretest.c and, when DEBUG is defined, into pcre.c, instead of having two
+    separate copies.
+
+(b) Defined the list of op-code names for debugging as a macro in
+    internal.h so that it is next to the definition of the opcodes.
+
+(c) Defined a table of op-code lengths for simpler skipping along compiled
+    code. This is again a macro in internal.h so that it is next to the
+    definition of the opcodes.
+
+34. Added support for recursive calls to individual subpatterns, along the
+lines of Robin Houston's patch (but implemented somewhat differently).
+
+35. Further mods to the Makefile to help Win32. Also, added code to pcregrep to
+allow it to read and process whole directories in Win32. This code was
+contributed by Lionel Fourquaux; it has not been tested by me.
+
+36. Added support for named subpatterns. The Python syntax (?P<name>...) is
+used to name a group. Names consist of alphanumerics and underscores, and must
+be unique. Back references use the syntax (?P=name) and recursive calls use
+(?P>name) which is a PCRE extension to the Python extension. Groups still have
+numbers. The function pcre_fullinfo() can be used after compilation to extract
+a name/number map. There are three relevant calls:
+
+  PCRE_INFO_NAMEENTRYSIZE        yields the size of each entry in the map
+  PCRE_INFO_NAMECOUNT            yields the number of entries
+  PCRE_INFO_NAMETABLE            yields a pointer to the map.
+
+The map is a vector of fixed-size entries. The size of each entry depends on
+the length of the longest name used. The first two bytes of each entry are the
+group number, most significant byte first. There follows the corresponding
+name, zero terminated. The names are in alphabetical order.
+
+37. Make the maximum literal string in the compiled code 250 for the non-UTF-8
+case instead of 255. Making it the same both with and without UTF-8 support
+means that the same test output works with both.
+
+38. There was a case of malloc(0) in the POSIX testing code in pcretest. Avoid
+calling malloc() with a zero argument.
+
+39. Change 25 above had to resort to a heavy-handed test for the .* anchoring
+optimization. I've improved things by keeping a bitmap of backreferences with
+numbers 1-31 so that if .* occurs inside capturing brackets that are not in
+fact referenced, the optimization can be applied. It is unlikely that a
+relevant occurrence of .* (i.e. one which might indicate anchoring or forcing
+the match to follow \n) will appear inside brackets with a number greater than
+31, but if it does, any back reference > 31 suppresses the optimization.
+
+40. Added a new compile-time option PCRE_NO_AUTO_CAPTURE. This has the effect
+of disabling numbered capturing parentheses. Any opening parenthesis that is
+not followed by ? behaves as if it were followed by ?: but named parentheses
+can still be used for capturing (and they will acquire numbers in the usual
+way).
+
+41. Redesigned the return codes from the match() function into yes/no/error so
+that errors can be passed back from deep inside the nested calls. A malloc
+failure while inside a recursive subpattern call now causes the
+PCRE_ERROR_NOMEMORY return instead of quietly going wrong.
+
+42. It is now possible to set a limit on the number of times the match()
+function is called in a call to pcre_exec(). This facility makes it possible to
+limit the amount of recursion and backtracking, though not in a directly
+obvious way, because the match() function is used in a number of different
+circumstances. The count starts from zero for each position in the subject
+string (for non-anchored patterns). The default limit is, for compatibility, a
+large number, namely 10 000 000. You can change this in two ways:
+
+(a) When configuring PCRE before making, you can use --with-match-limit=n
+    to set a default value for the compiled library.
+
+(b) For each call to pcre_exec(), you can pass a pcre_extra block in which
+    a different value is set. See 45 below.
+
+If the limit is exceeded, pcre_exec() returns PCRE_ERROR_MATCHLIMIT.
+
+43. Added a new function pcre_config(int, void *) to enable run-time extraction
+of things that can be changed at compile time. The first argument specifies
+what is wanted and the second points to where the information is to be placed.
+The current list of available information is:
+
+  PCRE_CONFIG_UTF8
+
+The output is an integer that is set to one if UTF-8 support is available;
+otherwise it is set to zero.
+
+  PCRE_CONFIG_NEWLINE
+
+The output is an integer that it set to the value of the code that is used for
+newline. It is either LF (10) or CR (13).
+
+  PCRE_CONFIG_LINK_SIZE
+
+The output is an integer that contains the number of bytes used for internal
+linkage in compiled expressions. The value is 2, 3, or 4. See item 32 above.
+
+  PCRE_CONFIG_POSIX_MALLOC_THRESHOLD
+
+The output is an integer that contains the threshold above which the POSIX
+interface uses malloc() for output vectors. See item 31 above.
+
+  PCRE_CONFIG_MATCH_LIMIT
+
+The output is an unsigned integer that contains the default limit of the number
+of match() calls in a pcre_exec() execution. See 42 above.
+
+44. pcretest has been upgraded by the addition of the -C option. This causes it
+to extract all the available output from the new pcre_config() function, and to
+output it. The program then exits immediately.
+
+45. A need has arisen to pass over additional data with calls to pcre_exec() in
+order to support additional features. One way would have been to define
+pcre_exec2() (for example) with extra arguments, but this would not have been
+extensible, and would also have required all calls to the original function to
+be mapped to the new one. Instead, I have chosen to extend the mechanism that
+is used for passing in "extra" data from pcre_study().
+
+The pcre_extra structure is now exposed and defined in pcre.h. It currently
+contains the following fields:
+
+  flags         a bitmap indicating which of the following fields are set
+  study_data    opaque data from pcre_study()
+  match_limit   a way of specifying a limit on match() calls for a specific
+                  call to pcre_exec()
+  callout_data  data for callouts (see 49 below)
+
+The flag bits are also defined in pcre.h, and are
+
+  PCRE_EXTRA_STUDY_DATA
+  PCRE_EXTRA_MATCH_LIMIT
+  PCRE_EXTRA_CALLOUT_DATA
+
+The pcre_study() function now returns one of these new pcre_extra blocks, with
+the actual study data pointed to by the study_data field, and the
+PCRE_EXTRA_STUDY_DATA flag set. This can be passed directly to pcre_exec() as
+before. That is, this change is entirely upwards-compatible and requires no
+change to existing code.
+
+If you want to pass in additional data to pcre_exec(), you can either place it
+in a pcre_extra block provided by pcre_study(), or create your own pcre_extra
+block.
+
+46. pcretest has been extended to test the PCRE_EXTRA_MATCH_LIMIT feature. If a
+data string contains the escape sequence \M, pcretest calls pcre_exec() several
+times with different match limits, until it finds the minimum value needed for
+pcre_exec() to complete. The value is then output. This can be instructive; for
+most simple matches the number is quite small, but for pathological cases it
+gets very large very quickly.
+
+47. There's a new option for pcre_fullinfo() called PCRE_INFO_STUDYSIZE. It
+returns the size of the data block pointed to by the study_data field in a
+pcre_extra block, that is, the value that was passed as the argument to
+pcre_malloc() when PCRE was getting memory in which to place the information
+created by pcre_study(). The fourth argument should point to a size_t variable.
+pcretest has been extended so that this information is shown after a successful
+pcre_study() call when information about the compiled regex is being displayed.
+
+48. Cosmetic change to Makefile: there's no need to have / after $(DESTDIR)
+because what follows is always an absolute path. (Later: it turns out that this
+is more than cosmetic for MinGW, because it doesn't like empty path
+components.)
+
+49. Some changes have been made to the callout feature (see 28 above):
+
+(i)  A callout function now has three choices for what it returns:
+
+       0  =>  success, carry on matching
+     > 0  =>  failure at this point, but backtrack if possible
+     < 0  =>  serious error, return this value from pcre_exec()
+
+     Negative values should normally be chosen from the set of PCRE_ERROR_xxx
+     values. In particular, returning PCRE_ERROR_NOMATCH forces a standard
+     "match failed" error. The error number PCRE_ERROR_CALLOUT is reserved for
+     use by callout functions. It will never be used by PCRE itself.
+
+(ii) The pcre_extra structure (see 45 above) has a void * field called
+     callout_data, with corresponding flag bit PCRE_EXTRA_CALLOUT_DATA. The
+     pcre_callout_block structure has a field of the same name. The contents of
+     the field passed in the pcre_extra structure are passed to the callout
+     function in the corresponding field in the callout block. This makes it
+     easier to use the same callout-containing regex from multiple threads. For
+     testing, the pcretest program has a new data escape
+
+       \C*n        pass the number n (may be negative) as callout_data
+
+     If the callout function in pcretest receives a non-zero value as
+     callout_data, it returns that value.
+
+50. Makefile wasn't handling CFLAGS properly when compiling dftables. Also,
+there were some redundant $(CFLAGS) in commands that are now specified as
+$(LINK), which already includes $(CFLAGS).
+
+51. Extensions to UTF-8 support are listed below. These all apply when (a) PCRE
+has been compiled with UTF-8 support *and* pcre_compile() has been compiled
+with the PCRE_UTF8 flag. Patterns that are compiled without that flag assume
+one-byte characters throughout. Note that case-insensitive matching applies
+only to characters whose values are less than 256. PCRE doesn't support the
+notion of cases for higher-valued characters.
+
+(i)   A character class whose characters are all within 0-255 is handled as
+      a bit map, and the map is inverted for negative classes. Previously, a
+      character > 255 always failed to match such a class; however it should
+      match if the class was a negative one (e.g. [^ab]). This has been fixed.
+
+(ii)  A negated character class with a single character < 255 is coded as
+      "not this character" (OP_NOT). This wasn't working properly when the test
+      character was multibyte, either singly or repeated.
+
+(iii) Repeats of multibyte characters are now handled correctly in UTF-8
+      mode, for example: \x{100}{2,3}.
+
+(iv)  The character escapes \b, \B, \d, \D, \s, \S, \w, and \W (either
+      singly or repeated) now correctly test multibyte characters. However,
+      PCRE doesn't recognize any characters with values greater than 255 as
+      digits, spaces, or word characters. Such characters always match \D, \S,
+      and \W, and never match \d, \s, or \w.
+
+(v)   Classes may now contain characters and character ranges with values
+      greater than 255. For example: [ab\x{100}-\x{400}].
+
+(vi)  pcregrep now has a --utf-8 option (synonym -u) which makes it call
+      PCRE in UTF-8 mode.
+
+52. The info request value PCRE_INFO_FIRSTCHAR has been renamed
+PCRE_INFO_FIRSTBYTE because it is a byte value. However, the old name is
+retained for backwards compatibility. (Note that LASTLITERAL is also a byte
+value.)
+
+53. The single man page has become too large. I have therefore split it up into
+a number of separate man pages. These also give rise to individual HTML pages;
+these are now put in a separate directory, and there is an index.html page that
+lists them all. Some hyperlinking between the pages has been installed.
+
+54. Added convenience functions for handling named capturing parentheses.
+
+55. Unknown escapes inside character classes (e.g. [\M]) and escapes that
+aren't interpreted therein (e.g. [\C]) are literals in Perl. This is now also
+true in PCRE, except when the PCRE_EXTENDED option is set, in which case they
+are faulted.
+
+56. Introduced HOST_CC and HOST_CFLAGS which can be set in the environment when
+calling configure. These values are used when compiling the dftables.c program
+which is run to generate the source of the default character tables. They
+default to the values of CC and CFLAGS. If you are cross-compiling PCRE,
+you will need to set these values.
+
+57. Updated the building process for Windows DLL, as provided by Fred Cox.
+
+
+Version 3.9 02-Jan-02
+---------------------
+
+1. A bit of extraneous text had somehow crept into the pcregrep documentation.
+
+2. If --disable-static was given, the building process failed when trying to
+build pcretest and pcregrep. (For some reason it was using libtool to compile
+them, which is not right, as they aren't part of the library.)
+
+
+Version 3.8 18-Dec-01
+---------------------
+
+1. The experimental UTF-8 code was completely screwed up. It was packing the
+bytes in the wrong order. How dumb can you get?
+
+
+Version 3.7 29-Oct-01
+---------------------
+
+1. In updating pcretest to check change 1 of version 3.6, I screwed up.
+This caused pcretest, when used on the test data, to segfault. Unfortunately,
+this didn't happen under Solaris 8, where I normally test things.
+
+2. The Makefile had to be changed to make it work on BSD systems, where 'make'
+doesn't seem to recognize that ./xxx and xxx are the same file. (This entry
+isn't in ChangeLog distributed with 3.7 because I forgot when I hastily made
+this fix an hour or so after the initial 3.7 release.)
+
+
+Version 3.6 23-Oct-01
+---------------------
+
+1. Crashed with /(sens|respons)e and \1ibility/ and "sense and sensibility" if
+offsets passed as NULL with zero offset count.
+
+2. The config.guess and config.sub files had not been updated when I moved to
+the latest autoconf.
+
+
+Version 3.5 15-Aug-01
+---------------------
+
+1. Added some missing #if !defined NOPOSIX conditionals in pcretest.c that
+had been forgotten.
+
+2. By using declared but undefined structures, we can avoid using "void"
+definitions in pcre.h while keeping the internal definitions of the structures
+private.
+
+3. The distribution is now built using autoconf 2.50 and libtool 1.4. From a
+user point of view, this means that both static and shared libraries are built
+by default, but this can be individually controlled. More of the work of
+handling this static/shared cases is now inside libtool instead of PCRE's make
+file.
+
+4. The pcretest utility is now installed along with pcregrep because it is
+useful for users (to test regexs) and by doing this, it automatically gets
+relinked by libtool. The documentation has been turned into a man page, so
+there are now .1, .txt, and .html versions in /doc.
+
+5. Upgrades to pcregrep:
+   (i)   Added long-form option names like gnu grep.
+   (ii)  Added --help to list all options with an explanatory phrase.
+   (iii) Added -r, --recursive to recurse into sub-directories.
+   (iv)  Added -f, --file to read patterns from a file.
+
+6. pcre_exec() was referring to its "code" argument before testing that
+argument for NULL (and giving an error if it was NULL).
+
+7. Upgraded Makefile.in to allow for compiling in a different directory from
+the source directory.
+
+8. Tiny buglet in pcretest: when pcre_fullinfo() was called to retrieve the
+options bits, the pointer it was passed was to an int instead of to an unsigned
+long int. This mattered only on 64-bit systems.
+
+9. Fixed typo (3.4/1) in pcre.h again. Sigh. I had changed pcre.h (which is
+generated) instead of pcre.in, which it its source. Also made the same change
+in several of the .c files.
+
+10. A new release of gcc defines printf() as a macro, which broke pcretest
+because it had an ifdef in the middle of a string argument for printf(). Fixed
+by using separate calls to printf().
+
+11. Added --enable-newline-is-cr and --enable-newline-is-lf to the configure
+script, to force use of CR or LF instead of \n in the source. On non-Unix
+systems, the value can be set in config.h.
+
+12. The limit of 200 on non-capturing parentheses is a _nesting_ limit, not an
+absolute limit. Changed the text of the error message to make this clear, and
+likewise updated the man page.
+
+13. The limit of 99 on the number of capturing subpatterns has been removed.
+The new limit is 65535, which I hope will not be a "real" limit.
+
+
+Version 3.4 22-Aug-00
+---------------------
+
+1. Fixed typo in pcre.h: unsigned const char * changed to const unsigned char *.
+
+2. Diagnose condition (?(0) as an error instead of crashing on matching.
+
+
+Version 3.3 01-Aug-00
+---------------------
+
+1. If an octal character was given, but the value was greater than \377, it
+was not getting masked to the least significant bits, as documented. This could
+lead to crashes in some systems.
+
+2. Perl 5.6 (if not earlier versions) accepts classes like [a-\d] and treats
+the hyphen as a literal. PCRE used to give an error; it now behaves like Perl.
+
+3. Added the functions pcre_free_substring() and pcre_free_substring_list().
+These just pass their arguments on to (pcre_free)(), but they are provided
+because some uses of PCRE bind it to non-C systems that can call its functions,
+but cannot call free() or pcre_free() directly.
+
+4. Add "make test" as a synonym for "make check". Corrected some comments in
+the Makefile.
+
+5. Add $(DESTDIR)/ in front of all the paths in the "install" target in the
+Makefile.
+
+6. Changed the name of pgrep to pcregrep, because Solaris has introduced a
+command called pgrep for grepping around the active processes.
+
+7. Added the beginnings of support for UTF-8 character strings.
+
+8. Arranged for the Makefile to pass over the settings of CC, CFLAGS, and
+RANLIB to ./ltconfig so that they are used by libtool. I think these are all
+the relevant ones. (AR is not passed because ./ltconfig does its own figuring
+out for the ar command.)
+
+
+Version 3.2 12-May-00
+---------------------
+
+This is purely a bug fixing release.
+
+1. If the pattern /((Z)+|A)*/ was matched agained ZABCDEFG it matched Z instead
+of ZA. This was just one example of several cases that could provoke this bug,
+which was introduced by change 9 of version 2.00. The code for breaking
+infinite loops after an iteration that matches an empty string was't working
+correctly.
+
+2. The pcretest program was not imitating Perl correctly for the pattern /a*/g
+when matched against abbab (for example). After matching an empty string, it
+wasn't forcing anchoring when setting PCRE_NOTEMPTY for the next attempt; this
+caused it to match further down the string than it should.
+
+3. The code contained an inclusion of sys/types.h. It isn't clear why this
+was there because it doesn't seem to be needed, and it causes trouble on some
+systems, as it is not a Standard C header. It has been removed.
+
+4. Made 4 silly changes to the source to avoid stupid compiler warnings that
+were reported on the Macintosh. The changes were from
+
+  while ((c = *(++ptr)) != 0 && c != '\n');
+to
+  while ((c = *(++ptr)) != 0 && c != '\n') ;
+
+Totally extraordinary, but if that's what it takes...
+
+5. PCRE is being used in one environment where neither memmove() nor bcopy() is
+available. Added HAVE_BCOPY and an autoconf test for it; if neither
+HAVE_MEMMOVE nor HAVE_BCOPY is set, use a built-in emulation function which
+assumes the way PCRE uses memmove() (always moving upwards).
+
+6. PCRE is being used in one environment where strchr() is not available. There
+was only one use in pcre.c, and writing it out to avoid strchr() probably gives
+faster code anyway.
+
+
+Version 3.1 09-Feb-00
+---------------------
+
+The only change in this release is the fixing of some bugs in Makefile.in for
+the "install" target:
+
+(1) It was failing to install pcreposix.h.
+
+(2) It was overwriting the pcre.3 man page with the pcreposix.3 man page.
+
+
+Version 3.0 01-Feb-00
+---------------------
+
+1. Add support for the /+ modifier to perltest (to output $` like it does in
+pcretest).
+
+2. Add support for the /g modifier to perltest.
+
+3. Fix pcretest so that it behaves even more like Perl for /g when the pattern
+matches null strings.
+
+4. Fix perltest so that it doesn't do unwanted things when fed an empty
+pattern. Perl treats empty patterns specially - it reuses the most recent
+pattern, which is not what we want. Replace // by /(?#)/ in order to avoid this
+effect.
+
+5. The POSIX interface was broken in that it was just handing over the POSIX
+captured string vector to pcre_exec(), but (since release 2.00) PCRE has
+required a bigger vector, with some working space on the end. This means that
+the POSIX wrapper now has to get and free some memory, and copy the results.
+
+6. Added some simple autoconf support, placing the test data and the
+documentation in separate directories, re-organizing some of the
+information files, and making it build pcre-config (a GNU standard). Also added
+libtool support for building PCRE as a shared library, which is now the
+default.
+
+7. Got rid of the leading zero in the definition of PCRE_MINOR because 08 and
+09 are not valid octal constants. Single digits will be used for minor values
+less than 10.
+
+8. Defined REG_EXTENDED and REG_NOSUB as zero in the POSIX header, so that
+existing programs that set these in the POSIX interface can use PCRE without
+modification.
+
+9. Added a new function, pcre_fullinfo() with an extensible interface. It can
+return all that pcre_info() returns, plus additional data. The pcre_info()
+function is retained for compatibility, but is considered to be obsolete.
+
+10. Added experimental recursion feature (?R) to handle one common case that
+Perl 5.6 will be able to do with (?p{...}).
+
+11. Added support for POSIX character classes like [:alpha:], which Perl is
+adopting.
+
+
+Version 2.08 31-Aug-99
+----------------------
+
+1. When startoffset was not zero and the pattern began with ".*", PCRE was not
+trying to match at the startoffset position, but instead was moving forward to
+the next newline as if a previous match had failed.
+
+2. pcretest was not making use of PCRE_NOTEMPTY when repeating for /g and /G,
+and could get into a loop if a null string was matched other than at the start
+of the subject.
+
+3. Added definitions of PCRE_MAJOR and PCRE_MINOR to pcre.h so the version can
+be distinguished at compile time, and for completeness also added PCRE_DATE.
+
+5. Added Paul Sokolovsky's minor changes to make it easy to compile a Win32 DLL
+in GnuWin32 environments.
+
+
+Version 2.07 29-Jul-99
+----------------------
+
+1. The documentation is now supplied in plain text form and HTML as well as in
+the form of man page sources.
+
+2. C++ compilers don't like assigning (void *) values to other pointer types.
+In particular this affects malloc(). Although there is no problem in Standard
+C, I've put in casts to keep C++ compilers happy.
+
+3. Typo on pcretest.c; a cast of (unsigned char *) in the POSIX regexec() call
+should be (const char *).
+
+4. If NOPOSIX is defined, pcretest.c compiles without POSIX support. This may
+be useful for non-Unix systems who don't want to bother with the POSIX stuff.
+However, I haven't made this a standard facility. The documentation doesn't
+mention it, and the Makefile doesn't support it.
+
+5. The Makefile now contains an "install" target, with editable destinations at
+the top of the file. The pcretest program is not installed.
+
+6. pgrep -V now gives the PCRE version number and date.
+
+7. Fixed bug: a zero repetition after a literal string (e.g. /abcde{0}/) was
+causing the entire string to be ignored, instead of just the last character.
+
+8. If a pattern like /"([^\\"]+|\\.)*"/ is applied in the normal way to a
+non-matching string, it can take a very, very long time, even for strings of
+quite modest length, because of the nested recursion. PCRE now does better in
+some of these cases. It does this by remembering the last required literal
+character in the pattern, and pre-searching the subject to ensure it is present
+before running the real match. In other words, it applies a heuristic to detect
+some types of certain failure quickly, and in the above example, if presented
+with a string that has no trailing " it gives "no match" very quickly.
+
+9. A new runtime option PCRE_NOTEMPTY causes null string matches to be ignored;
+other alternatives are tried instead.
+
+
+Version 2.06 09-Jun-99
+----------------------
+
+1. Change pcretest's output for amount of store used to show just the code
+space, because the remainder (the data block) varies in size between 32-bit and
+64-bit systems.
+
+2. Added an extra argument to pcre_exec() to supply an offset in the subject to
+start matching at. This allows lookbehinds to work when searching for multiple
+occurrences in a string.
+
+3. Added additional options to pcretest for testing multiple occurrences:
+
+   /+   outputs the rest of the string that follows a match
+   /g   loops for multiple occurrences, using the new startoffset argument
+   /G   loops for multiple occurrences by passing an incremented pointer
+
+4. PCRE wasn't doing the "first character" optimization for patterns starting
+with \b or \B, though it was doing it for other lookbehind assertions. That is,
+it wasn't noticing that a match for a pattern such as /\bxyz/ has to start with
+the letter 'x'. On long subject strings, this gives a significant speed-up.
+
+
+Version 2.05 21-Apr-99
+----------------------
+
+1. Changed the type of magic_number from int to long int so that it works
+properly on 16-bit systems.
+
+2. Fixed a bug which caused patterns starting with .* not to work correctly
+when the subject string contained newline characters. PCRE was assuming
+anchoring for such patterns in all cases, which is not correct because .* will
+not pass a newline unless PCRE_DOTALL is set. It now assumes anchoring only if
+DOTALL is set at top level; otherwise it knows that patterns starting with .*
+must be retried after every newline in the subject.
+
+
+Version 2.04 18-Feb-99
+----------------------
+
+1. For parenthesized subpatterns with repeats whose minimum was zero, the
+computation of the store needed to hold the pattern was incorrect (too large).
+If such patterns were nested a few deep, this could multiply and become a real
+problem.
+
+2. Added /M option to pcretest to show the memory requirement of a specific
+pattern. Made -m a synonym of -s (which does this globally) for compatibility.
+
+3. Subpatterns of the form (regex){n,m} (i.e. limited maximum) were being
+compiled in such a way that the backtracking after subsequent failure was
+pessimal. Something like (a){0,3} was compiled as (a)?(a)?(a)? instead of
+((a)((a)(a)?)?)? with disastrous performance if the maximum was of any size.
+
+
+Version 2.03 02-Feb-99
+----------------------
+
+1. Fixed typo and small mistake in man page.
+
+2. Added 4th condition (GPL supersedes if conflict) and created separate
+LICENCE file containing the conditions.
+
+3. Updated pcretest so that patterns such as /abc\/def/ work like they do in
+Perl, that is the internal \ allows the delimiter to be included in the
+pattern. Locked out the use of \ as a delimiter. If \ immediately follows
+the final delimiter, add \ to the end of the pattern (to test the error).
+
+4. Added the convenience functions for extracting substrings after a successful
+match. Updated pcretest to make it able to test these functions.
+
+
+Version 2.02 14-Jan-99
+----------------------
+
+1. Initialized the working variables associated with each extraction so that
+their saving and restoring doesn't refer to uninitialized store.
+
+2. Put dummy code into study.c in order to trick the optimizer of the IBM C
+compiler for OS/2 into generating correct code. Apparently IBM isn't going to
+fix the problem.
+
+3. Pcretest: the timing code wasn't using LOOPREPEAT for timing execution
+calls, and wasn't printing the correct value for compiling calls. Increased the
+default value of LOOPREPEAT, and the number of significant figures in the
+times.
+
+4. Changed "/bin/rm" in the Makefile to "-rm" so it works on Windows NT.
+
+5. Renamed "deftables" as "dftables" to get it down to 8 characters, to avoid
+a building problem on Windows NT with a FAT file system.
+
+
+Version 2.01 21-Oct-98
+----------------------
+
+1. Changed the API for pcre_compile() to allow for the provision of a pointer
+to character tables built by pcre_maketables() in the current locale. If NULL
+is passed, the default tables are used.
+
+
+Version 2.00 24-Sep-98
+----------------------
+
+1. Since the (>?) facility is in Perl 5.005, don't require PCRE_EXTRA to enable
+it any more.
+
+2. Allow quantification of (?>) groups, and make it work correctly.
+
+3. The first character computation wasn't working for (?>) groups.
+
+4. Correct the implementation of \Z (it is permitted to match on the \n at the
+end of the subject) and add 5.005's \z, which really does match only at the
+very end of the subject.
+
+5. Remove the \X "cut" facility; Perl doesn't have it, and (?> is neater.
+
+6. Remove the ability to specify CASELESS, MULTILINE, DOTALL, and
+DOLLAR_END_ONLY at runtime, to make it possible to implement the Perl 5.005
+localized options. All options to pcre_study() were also removed.
+
+7. Add other new features from 5.005:
+
+   $(?<=           positive lookbehind
+   $(?<!           negative lookbehind
+   (?imsx-imsx)    added the unsetting capability
+                   such a setting is global if at outer level; local otherwise
+   (?imsx-imsx:)   non-capturing groups with option setting
+   (?(cond)re|re)  conditional pattern matching
+
+   A backreference to itself in a repeated group matches the previous
+   captured string.
+
+8. General tidying up of studying (both automatic and via "study")
+consequential on the addition of new assertions.
+
+9. As in 5.005, unlimited repeated groups that could match an empty substring
+are no longer faulted at compile time. Instead, the loop is forcibly broken at
+runtime if any iteration does actually match an empty substring.
+
+10. Include the RunTest script in the distribution.
+
+11. Added tests from the Perl 5.005_02 distribution. This showed up a few
+discrepancies, some of which were old and were also with respect to 5.004. They
+have now been fixed.
+
+
+Version 1.09 28-Apr-98
+----------------------
+
+1. A negated single character class followed by a quantifier with a minimum
+value of one (e.g.  [^x]{1,6}  ) was not compiled correctly. This could lead to
+program crashes, or just wrong answers. This did not apply to negated classes
+containing more than one character, or to minima other than one.
+
+
+Version 1.08 27-Mar-98
+----------------------
+
+1. Add PCRE_UNGREEDY to invert the greediness of quantifiers.
+
+2. Add (?U) and (?X) to set PCRE_UNGREEDY and PCRE_EXTRA respectively. The
+latter must appear before anything that relies on it in the pattern.
+
+
+Version 1.07 16-Feb-98
+----------------------
+
+1. A pattern such as /((a)*)*/ was not being diagnosed as in error (unlimited
+repeat of a potentially empty string).
+
+
+Version 1.06 23-Jan-98
+----------------------
+
+1. Added Markus Oberhumer's little patches for C++.
+
+2. Literal strings longer than 255 characters were broken.
+
+
+Version 1.05 23-Dec-97
+----------------------
+
+1. Negated character classes containing more than one character were failing if
+PCRE_CASELESS was set at run time.
+
+
+Version 1.04 19-Dec-97
+----------------------
+
+1. Corrected the man page, where some "const" qualifiers had been omitted.
+
+2. Made debugging output print "{0,xxx}" instead of just "{,xxx}" to agree with
+input syntax.
+
+3. Fixed memory leak which occurred when a regex with back references was
+matched with an offsets vector that wasn't big enough. The temporary memory
+that is used in this case wasn't being freed if the match failed.
+
+4. Tidied pcretest to ensure it frees memory that it gets.
+
+5. Temporary memory was being obtained in the case where the passed offsets
+vector was exactly big enough.
+
+6. Corrected definition of offsetof() from change 5 below.
+
+7. I had screwed up change 6 below and broken the rules for the use of
+setjmp(). Now fixed.
+
+
+Version 1.03 18-Dec-97
+----------------------
+
+1. A erroneous regex with a missing opening parenthesis was correctly
+diagnosed, but PCRE attempted to access brastack[-1], which could cause crashes
+on some systems.
+
+2. Replaced offsetof(real_pcre, code) by offsetof(real_pcre, code[0]) because
+it was reported that one broken compiler failed on the former because "code" is
+also an independent variable.
+
+3. The erroneous regex a[]b caused an array overrun reference.
+
+4. A regex ending with a one-character negative class (e.g. /[^k]$/) did not
+fail on data ending with that character. (It was going on too far, and checking
+the next character, typically a binary zero.) This was specific to the
+optimized code for single-character negative classes.
+
+5. Added a contributed patch from the TIN world which does the following:
+
+  + Add an undef for memmove, in case the the system defines a macro for it.
+
+  + Add a definition of offsetof(), in case there isn't one. (I don't know
+    the reason behind this - offsetof() is part of the ANSI standard - but
+    it does no harm).
+
+  + Reduce the ifdef's in pcre.c using macro DPRINTF, thereby eliminating
+    most of the places where whitespace preceded '#'. I have given up and
+    allowed the remaining 2 cases to be at the margin.
+
+  + Rename some variables in pcre to eliminate shadowing. This seems very
+    pedantic, but does no harm, of course.
+
+6. Moved the call to setjmp() into its own function, to get rid of warnings
+from gcc -Wall, and avoided calling it at all unless PCRE_EXTRA is used.
+
+7. Constructs such as \d{8,} were compiling into the equivalent of
+\d{8}\d{0,65527} instead of \d{8}\d* which didn't make much difference to the
+outcome, but in this particular case used more store than had been allocated,
+which caused the bug to be discovered because it threw up an internal error.
+
+8. The debugging code in both pcre and pcretest for outputting the compiled
+form of a regex was going wrong in the case of back references followed by
+curly-bracketed repeats.
+
+
+Version 1.02 12-Dec-97
+----------------------
+
+1. Typos in pcre.3 and comments in the source fixed.
+
+2. Applied a contributed patch to get rid of places where it used to remove
+'const' from variables, and fixed some signed/unsigned and uninitialized
+variable warnings.
+
+3. Added the "runtest" target to Makefile.
+
+4. Set default compiler flag to -O2 rather than just -O.
+
+
+Version 1.01 19-Nov-97
+----------------------
+
+1. PCRE was failing to diagnose unlimited repeat of empty string for patterns
+like /([ab]*)*/, that is, for classes with more than one character in them.
+
+2. Likewise, it wasn't diagnosing patterns with "once-only" subpatterns, such
+as /((?>a*))*/ (a PCRE_EXTRA facility).
+
+
+Version 1.00 18-Nov-97
+----------------------
+
+1. Added compile-time macros to support systems such as SunOS4 which don't have
+memmove() or strerror() but have other things that can be used instead.
+
+2. Arranged that "make clean" removes the executables.
+
+
+Version 0.99 27-Oct-97
+----------------------
+
+1. Fixed bug in code for optimizing classes with only one character. It was
+initializing a 32-byte map regardless, which could cause it to run off the end
+of the memory it had got.
+
+2. Added, conditional on PCRE_EXTRA, the proposed (?>REGEX) construction.
+
+
+Version 0.98 22-Oct-97
+----------------------
+
+1. Fixed bug in code for handling temporary memory usage when there are more
+back references than supplied space in the ovector. This could cause segfaults.
+
+
+Version 0.97 21-Oct-97
+----------------------
+
+1. Added the \X "cut" facility, conditional on PCRE_EXTRA.
+
+2. Optimized negated single characters not to use a bit map.
+
+3. Brought error texts together as macro definitions; clarified some of them;
+fixed one that was wrong - it said "range out of order" when it meant "invalid
+escape sequence".
+
+4. Changed some char * arguments to const char *.
+
+5. Added PCRE_NOTBOL and PCRE_NOTEOL (from POSIX).
+
+6. Added the POSIX-style API wrapper in pcreposix.a and testing facilities in
+pcretest.
+
+
+Version 0.96 16-Oct-97
+----------------------
+
+1. Added a simple "pgrep" utility to the distribution.
+
+2. Fixed an incompatibility with Perl: "{" is now treated as a normal character
+unless it appears in one of the precise forms "{ddd}", "{ddd,}", or "{ddd,ddd}"
+where "ddd" means "one or more decimal digits".
+
+3. Fixed serious bug. If a pattern had a back reference, but the call to
+pcre_exec() didn't supply a large enough ovector to record the related
+identifying subpattern, the match always failed. PCRE now remembers the number
+of the largest back reference, and gets some temporary memory in which to save
+the offsets during matching if necessary, in order to ensure that
+backreferences always work.
+
+4. Increased the compatibility with Perl in a number of ways:
+
+  (a) . no longer matches \n by default; an option PCRE_DOTALL is provided
+      to request this handling. The option can be set at compile or exec time.
+
+  (b) $ matches before a terminating newline by default; an option
+      PCRE_DOLLAR_ENDONLY is provided to override this (but not in multiline
+      mode). The option can be set at compile or exec time.
+
+  (c) The handling of \ followed by a digit other than 0 is now supposed to be
+      the same as Perl's. If the decimal number it represents is less than 10
+      or there aren't that many previous left capturing parentheses, an octal
+      escape is read. Inside a character class, it's always an octal escape,
+      even if it is a single digit.
+
+  (d) An escaped but undefined alphabetic character is taken as a literal,
+      unless PCRE_EXTRA is set. Currently this just reserves the remaining
+      escapes.
+
+  (e) {0} is now permitted. (The previous item is removed from the compiled
+      pattern).
+
+5. Changed all the names of code files so that the basic parts are no longer
+than 10 characters, and abolished the teeny "globals.c" file.
+
+6. Changed the handling of character classes; they are now done with a 32-byte
+bit map always.
+
+7. Added the -d and /D options to pcretest to make it possible to look at the
+internals of compilation without having to recompile pcre.
+
+
+Version 0.95 23-Sep-97
+----------------------
+
+1. Fixed bug in pre-pass concerning escaped "normal" characters such as \x5c or
+\x20 at the start of a run of normal characters. These were being treated as
+real characters, instead of the source characters being re-checked.
+
+
+Version 0.94 18-Sep-97
+----------------------
+
+1. The functions are now thread-safe, with the caveat that the global variables
+containing pointers to malloc() and free() or alternative functions are the
+same for all threads.
+
+2. Get pcre_study() to generate a bitmap of initial characters for non-
+anchored patterns when this is possible, and use it if passed to pcre_exec().
+
+
+Version 0.93 15-Sep-97
+----------------------
+
+1. /(b)|(:+)/ was computing an incorrect first character.
+
+2. Add pcre_study() to the API and the passing of pcre_extra to pcre_exec(),
+but not actually doing anything yet.
+
+3. Treat "-" characters in classes that cannot be part of ranges as literals,
+as Perl does (e.g. [-az] or [az-]).
+
+4. Set the anchored flag if a branch starts with .* or .*? because that tests
+all possible positions.
+
+5. Split up into different modules to avoid including unneeded functions in a
+compiled binary. However, compile and exec are still in one module. The "study"
+function is split off.
+
+6. The character tables are now in a separate module whose source is generated
+by an auxiliary program - but can then be edited by hand if required. There are
+now no calls to isalnum(), isspace(), isdigit(), isxdigit(), tolower() or
+toupper() in the code.
+
+7. Turn the malloc/free funtions variables into pcre_malloc and pcre_free and
+make them global. Abolish the function for setting them, as the caller can now
+set them directly.
+
+
+Version 0.92 11-Sep-97
+----------------------
+
+1. A repeat with a fixed maximum and a minimum of 1 for an ordinary character
+(e.g. /a{1,3}/) was broken (I mis-optimized it).
+
+2. Caseless matching was not working in character classes if the characters in
+the pattern were in upper case.
+
+3. Make ranges like [W-c] work in the same way as Perl for caseless matching.
+
+4. Make PCRE_ANCHORED public and accept as a compile option.
+
+5. Add an options word to pcre_exec() and accept PCRE_ANCHORED and
+PCRE_CASELESS at run time. Add escapes \A and \I to pcretest to cause it to
+pass them.
+
+6. Give an error if bad option bits passed at compile or run time.
+
+7. Add PCRE_MULTILINE at compile and exec time, and (?m) as well. Add \M to
+pcretest to cause it to pass that flag.
+
+8. Add pcre_info(), to get the number of identifying subpatterns, the stored
+options, and the first character, if set.
+
+9. Recognize C+ or C{n,m} where n >= 1 as providing a fixed starting character.
+
+
+Version 0.91 10-Sep-97
+----------------------
+
+1. PCRE was failing to diagnose unlimited repeats of subpatterns that could
+match the empty string as in /(a*)*/. It was looping and ultimately crashing.
+
+2. PCRE was looping on encountering an indefinitely repeated back reference to
+a subpattern that had matched an empty string, e.g. /(a|)\1*/. It now does what
+Perl does - treats the match as successful.
+
+****
diff --git a/libs/Pcre16/docs/HACKING b/libs/Pcre16/docs/HACKING
new file mode 100644
index 0000000000..691b7a14e5
--- /dev/null
+++ b/libs/Pcre16/docs/HACKING
@@ -0,0 +1,528 @@
+Technical Notes about PCRE
+--------------------------
+
+These are very rough technical notes that record potentially useful information 
+about PCRE internals. For information about testing PCRE, see the pcretest 
+documentation and the comment at the head of the RunTest file.
+
+
+Historical note 1
+-----------------
+
+Many years ago I implemented some regular expression functions to an algorithm
+suggested by Martin Richards. These were not Unix-like in form, and were quite
+restricted in what they could do by comparison with Perl. The interesting part
+about the algorithm was that the amount of space required to hold the compiled
+form of an expression was known in advance. The code to apply an expression did
+not operate by backtracking, as the original Henry Spencer code and current
+Perl code does, but instead checked all possibilities simultaneously by keeping
+a list of current states and checking all of them as it advanced through the
+subject string. In the terminology of Jeffrey Friedl's book, it was a "DFA
+algorithm", though it was not a traditional Finite State Machine (FSM). When
+the pattern was all used up, all remaining states were possible matches, and
+the one matching the longest subset of the subject string was chosen. This did
+not necessarily maximize the individual wild portions of the pattern, as is
+expected in Unix and Perl-style regular expressions.
+
+
+Historical note 2
+-----------------
+
+By contrast, the code originally written by Henry Spencer (which was
+subsequently heavily modified for Perl) compiles the expression twice: once in
+a dummy mode in order to find out how much store will be needed, and then for
+real. (The Perl version probably doesn't do this any more; I'm talking about
+the original library.) The execution function operates by backtracking and
+maximizing (or, optionally, minimizing in Perl) the amount of the subject that
+matches individual wild portions of the pattern. This is an "NFA algorithm" in
+Friedl's terminology.
+
+
+OK, here's the real stuff
+-------------------------
+
+For the set of functions that form the "basic" PCRE library (which are
+unrelated to those mentioned above), I tried at first to invent an algorithm
+that used an amount of store bounded by a multiple of the number of characters
+in the pattern, to save on compiling time. However, because of the greater
+complexity in Perl regular expressions, I couldn't do this. In any case, a
+first pass through the pattern is helpful for other reasons. 
+
+
+Support for 16-bit and 32-bit data strings
+-------------------------------------------
+
+From release 8.30, PCRE supports 16-bit as well as 8-bit data strings; and from
+release 8.32, PCRE supports 32-bit data strings. The library can be compiled
+in any combination of 8-bit, 16-bit or 32-bit modes, creating up to three
+different libraries. In the description that follows, the word "short" is used
+for a 16-bit data quantity, and the word "unit" is used for a quantity that is
+a byte in 8-bit mode, a short in 16-bit mode and a 32-bit word in 32-bit mode.
+However, so as not to over-complicate the text, the names of PCRE functions are
+given in 8-bit form only.
+
+
+Computing the memory requirement: how it was
+--------------------------------------------
+
+Up to and including release 6.7, PCRE worked by running a very degenerate first
+pass to calculate a maximum store size, and then a second pass to do the real
+compile - which might use a bit less than the predicted amount of memory. The
+idea was that this would turn out faster than the Henry Spencer code because
+the first pass is degenerate and the second pass can just store stuff straight
+into the vector, which it knows is big enough.
+
+
+Computing the memory requirement: how it is
+-------------------------------------------
+
+By the time I was working on a potential 6.8 release, the degenerate first pass
+had become very complicated and hard to maintain. Indeed one of the early
+things I did for 6.8 was to fix Yet Another Bug in the memory computation. Then
+I had a flash of inspiration as to how I could run the real compile function in
+a "fake" mode that enables it to compute how much memory it would need, while
+actually only ever using a few hundred bytes of working memory, and without too
+many tests of the mode that might slow it down. So I refactored the compiling
+functions to work this way. This got rid of about 600 lines of source. It
+should make future maintenance and development easier. As this was such a major 
+change, I never released 6.8, instead upping the number to 7.0 (other quite 
+major changes were also present in the 7.0 release).
+
+A side effect of this work was that the previous limit of 200 on the nesting
+depth of parentheses was removed. However, there is a downside: pcre_compile()
+runs more slowly than before (30% or more, depending on the pattern) because it
+is doing a full analysis of the pattern. My hope was that this would not be a
+big issue, and in the event, nobody has commented on it.
+
+At release 8.34, a limit on the nesting depth of parentheses was re-introduced
+(default 250, settable at build time) so as to put a limit on the amount of 
+system stack used by pcre_compile(). This is a safety feature for environments 
+with small stacks where the patterns are provided by users.
+
+
+Traditional matching function
+-----------------------------
+
+The "traditional", and original, matching function is called pcre_exec(), and 
+it implements an NFA algorithm, similar to the original Henry Spencer algorithm 
+and the way that Perl works. This is not surprising, since it is intended to be
+as compatible with Perl as possible. This is the function most users of PCRE
+will use most of the time. From release 8.20, if PCRE is compiled with 
+just-in-time (JIT) support, and studying a compiled pattern with JIT is 
+successful, the JIT code is run instead of the normal pcre_exec() code, but the 
+result is the same.
+
+
+Supplementary matching function
+-------------------------------
+
+From PCRE 6.0, there is also a supplementary matching function called 
+pcre_dfa_exec(). This implements a DFA matching algorithm that searches 
+simultaneously for all possible matches that start at one point in the subject 
+string. (Going back to my roots: see Historical Note 1 above.) This function 
+intreprets the same compiled pattern data as pcre_exec(); however, not all the 
+facilities are available, and those that are do not always work in quite the 
+same way. See the user documentation for details.
+
+The algorithm that is used for pcre_dfa_exec() is not a traditional FSM, 
+because it may have a number of states active at one time. More work would be
+needed at compile time to produce a traditional FSM where only one state is
+ever active at once. I believe some other regex matchers work this way. JIT
+support is not available for this kind of matching.
+
+
+Changeable options
+------------------
+
+The /i, /m, or /s options (PCRE_CASELESS, PCRE_MULTILINE, PCRE_DOTALL, and some 
+others) may change in the middle of patterns. From PCRE 8.13, their processing
+is handled entirely at compile time by generating different opcodes for the
+different settings. The runtime functions do not need to keep track of an
+options state any more.
+
+
+Format of compiled patterns
+---------------------------
+
+The compiled form of a pattern is a vector of unsigned units (bytes in 8-bit
+mode, shorts in 16-bit mode, 32-bit words in 32-bit mode), containing items of
+variable length. The first unit in an item contains an opcode, and the length
+of the item is either implicit in the opcode or contained in the data that
+follows it.
+
+In many cases listed below, LINK_SIZE data values are specified for offsets
+within the compiled pattern. LINK_SIZE always specifies a number of bytes. The
+default value for LINK_SIZE is 2, but PCRE can be compiled to use 3-byte or
+4-byte values for these offsets, although this impairs the performance. (3-byte
+LINK_SIZE values are available only in 8-bit mode.) Specifing a LINK_SIZE
+larger than 2 is necessary only when patterns whose compiled length is greater
+than 64K are going to be processed. In this description, we assume the "normal"
+compilation options. Data values that are counts (e.g. quantifiers) are two
+bytes long in 8-bit mode (most significant byte first), or one unit in 16-bit
+and 32-bit modes.
+
+
+Opcodes with no following data
+------------------------------
+
+These items are all just one unit long
+
+  OP_END                 end of pattern
+  OP_ANY                 match any one character other than newline
+  OP_ALLANY              match any one character, including newline
+  OP_ANYBYTE             match any single unit, even in UTF-8/16 mode
+  OP_SOD                 match start of data: \A
+  OP_SOM,                start of match (subject + offset): \G
+  OP_SET_SOM,            set start of match (\K) 
+  OP_CIRC                ^ (start of data)
+  OP_CIRCM               ^ multiline mode (start of data or after newline)
+  OP_NOT_WORD_BOUNDARY   \W
+  OP_WORD_BOUNDARY       \w
+  OP_NOT_DIGIT           \D
+  OP_DIGIT               \d
+  OP_NOT_HSPACE          \H
+  OP_HSPACE              \h  
+  OP_NOT_WHITESPACE      \S
+  OP_WHITESPACE          \s
+  OP_NOT_VSPACE          \V
+  OP_VSPACE              \v  
+  OP_NOT_WORDCHAR        \W
+  OP_WORDCHAR            \w
+  OP_EODN                match end of data or newline at end: \Z
+  OP_EOD                 match end of data: \z
+  OP_DOLL                $ (end of data, or before final newline)
+  OP_DOLLM               $ multiline mode (end of data or before newline)
+  OP_EXTUNI              match an extended Unicode grapheme cluster 
+  OP_ANYNL               match any Unicode newline sequence 
+  
+  OP_ASSERT_ACCEPT       )
+  OP_ACCEPT              ) These are Perl 5.10's "backtracking control   
+  OP_COMMIT              ) verbs". If OP_ACCEPT is inside capturing
+  OP_FAIL                ) parentheses, it may be preceded by one or more
+  OP_PRUNE               ) OP_CLOSE, each followed by a count that
+  OP_SKIP                ) indicates which parentheses must be closed.
+  OP_THEN                )
+  
+OP_ASSERT_ACCEPT is used when (*ACCEPT) is encountered within an assertion. 
+This ends the assertion, not the entire pattern match.  
+  
+
+Backtracking control verbs with optional data
+---------------------------------------------
+
+(*THEN) without an argument generates the opcode OP_THEN and no following data.
+OP_MARK is followed by the mark name, preceded by a one-unit length, and
+followed by a binary zero. For (*PRUNE), (*SKIP), and (*THEN) with arguments,
+the opcodes OP_PRUNE_ARG, OP_SKIP_ARG, and OP_THEN_ARG are used, with the name
+following in the same format as OP_MARK.
+  
+
+Matching literal characters
+---------------------------
+
+The OP_CHAR opcode is followed by a single character that is to be matched 
+casefully. For caseless matching, OP_CHARI is used. In UTF-8 or UTF-16 modes,
+the character may be more than one unit long. In UTF-32 mode, characters
+are always exactly one unit long.
+
+If there is only one character in a character class, OP_CHAR or OP_CHARI is
+used for a positive class, and OP_NOT or OP_NOTI for a negative one (that is,
+for something like [^a]).
+
+
+Repeating single characters
+---------------------------
+
+The common repeats (*, +, ?), when applied to a single character, use the
+following opcodes, which come in caseful and caseless versions:
+
+  Caseful         Caseless
+  OP_STAR         OP_STARI      
+  OP_MINSTAR      OP_MINSTARI   
+  OP_POSSTAR      OP_POSSTARI   
+  OP_PLUS         OP_PLUSI      
+  OP_MINPLUS      OP_MINPLUSI   
+  OP_POSPLUS      OP_POSPLUSI   
+  OP_QUERY        OP_QUERYI     
+  OP_MINQUERY     OP_MINQUERYI  
+  OP_POSQUERY     OP_POSQUERYI  
+
+Each opcode is followed by the character that is to be repeated. In ASCII mode,
+these are two-unit items; in UTF-8 or UTF-16 modes, the length is variable; in
+UTF-32 mode these are one-unit items. Those with "MIN" in their names are the
+minimizing versions. Those with "POS" in their names are possessive versions.
+Other repeats make use of these opcodes:
+
+  Caseful         Caseless
+  OP_UPTO         OP_UPTOI    
+  OP_MINUPTO      OP_MINUPTOI 
+  OP_POSUPTO      OP_POSUPTOI 
+  OP_EXACT        OP_EXACTI   
+
+Each of these is followed by a count and then the repeated character. OP_UPTO
+matches from 0 to the given number. A repeat with a non-zero minimum and a
+fixed maximum is coded as an OP_EXACT followed by an OP_UPTO (or OP_MINUPTO or
+OPT_POSUPTO).
+
+Another set of matching repeating opcodes (called OP_NOTSTAR, OP_NOTSTARI,
+etc.) are used for repeated, negated, single-character classes such as [^a]*.
+The normal single-character opcodes (OP_STAR, etc.) are used for repeated
+positive single-character classes.
+
+
+Repeating character types
+-------------------------
+
+Repeats of things like \d are done exactly as for single characters, except
+that instead of a character, the opcode for the type is stored in the data
+unit. The opcodes are:
+
+  OP_TYPESTAR
+  OP_TYPEMINSTAR
+  OP_TYPEPOSSTAR 
+  OP_TYPEPLUS
+  OP_TYPEMINPLUS
+  OP_TYPEPOSPLUS 
+  OP_TYPEQUERY
+  OP_TYPEMINQUERY
+  OP_TYPEPOSQUERY 
+  OP_TYPEUPTO
+  OP_TYPEMINUPTO
+  OP_TYPEPOSUPTO 
+  OP_TYPEEXACT
+
+
+Match by Unicode property
+-------------------------
+
+OP_PROP and OP_NOTPROP are used for positive and negative matches of a 
+character by testing its Unicode property (the \p and \P escape sequences).
+Each is followed by two units that encode the desired property as a type and a
+value. The types are a set of #defines of the form PT_xxx, and the values are
+enumerations of the form ucp_xx, defined in the ucp.h source file. The value is
+relevant only for PT_GC (General Category), PT_PC (Particular Category), and
+PT_SC (Script).
+
+Repeats of these items use the OP_TYPESTAR etc. set of opcodes, followed by
+three units: OP_PROP or OP_NOTPROP, and then the desired property type and
+value.
+
+
+Character classes
+-----------------
+
+If there is only one character in a class, OP_CHAR or OP_CHARI is used for a
+positive class, and OP_NOT or OP_NOTI for a negative one (that is, for
+something like [^a]). 
+
+A set of repeating opcodes (called OP_NOTSTAR etc.) are used for repeated,
+negated, single-character classes. The normal single-character opcodes
+(OP_STAR, etc.) are used for repeated positive single-character classes.
+
+When there is more than one character in a class, and all the code points are
+less than 256, OP_CLASS is used for a positive class, and OP_NCLASS for a
+negative one. In either case, the opcode is followed by a 32-byte (16-short, 
+8-word) bit map containing a 1 bit for every character that is acceptable. The
+bits are counted from the least significant end of each unit. In caseless mode,
+bits for both cases are set.
+
+The reason for having both OP_CLASS and OP_NCLASS is so that, in UTF-8/16/32
+mode, subject characters with values greater than 255 can be handled correctly.
+For OP_CLASS they do not match, whereas for OP_NCLASS they do.
+
+For classes containing characters with values greater than 255 or that contain 
+\p or \P, OP_XCLASS is used. It optionally uses a bit map if any code points
+are less than 256, followed by a list of pairs (for a range) and single
+characters. In caseless mode, both cases are explicitly listed.
+
+OP_XCLASS is followed by a unit containing flag bits: XCL_NOT indicates that 
+this is a negative class, and XCL_MAP indicates that a bit map is present.
+There follows the bit map, if XCL_MAP is set, and then a sequence of items
+coded as follows:
+
+  XCL_END      marks the end of the list
+  XCL_SINGLE   one character follows
+  XCL_RANGE    two characters follow
+  XCL_PROP     a Unicode property (type, value) follows   
+  XCL_NOTPROP  a Unicode property (type, value) follows   
+
+If a range starts with a code point less than 256 and ends with one greater 
+than 256, an XCL_RANGE item is used, without setting any bits in the bit map. 
+This means that if no other items in the class set bits in the map, a map is 
+not needed.
+
+
+Back references
+---------------
+
+OP_REF (caseful) or OP_REFI (caseless) is followed by a count containing the
+reference number if the reference is to a unique capturing group (either by
+number or by name). When named groups are used, there may be more than one
+group with the same name. In this case, a reference by name generates OP_DNREF
+or OP_DNREFI. These are followed by two counts: the index (not the byte offset) 
+in the group name table of the first entry for the requred name, followed by
+the number of groups with the same name.
+
+
+Repeating character classes and back references
+-----------------------------------------------
+
+Single-character classes are handled specially (see above). This section
+applies to other classes and also to back references. In both cases, the repeat
+information follows the base item. The matching code looks at the following
+opcode to see if it is one of
+
+  OP_CRSTAR
+  OP_CRMINSTAR
+  OP_CRPOSSTAR 
+  OP_CRPLUS
+  OP_CRMINPLUS
+  OP_CRPOSPLUS 
+  OP_CRQUERY
+  OP_CRMINQUERY
+  OP_CRPOSQUERY 
+  OP_CRRANGE
+  OP_CRMINRANGE
+  OP_CRPOSRANGE 
+
+All but the last three are single-unit items, with no data. The others are
+followed by the minimum and maximum repeat counts.
+
+
+Brackets and alternation
+------------------------
+
+A pair of non-capturing round brackets is wrapped round each expression at
+compile time, so alternation always happens in the context of brackets.
+
+[Note for North Americans: "bracket" to some English speakers, including
+myself, can be round, square, curly, or pointy. Hence this usage rather than 
+"parentheses".]
+
+Non-capturing brackets use the opcode OP_BRA. Originally PCRE was limited to 99
+capturing brackets and it used a different opcode for each one. From release
+3.5, the limit was removed by putting the bracket number into the data for
+higher-numbered brackets. From release 7.0 all capturing brackets are handled
+this way, using the single opcode OP_CBRA.
+
+A bracket opcode is followed by LINK_SIZE bytes which give the offset to the
+next alternative OP_ALT or, if there aren't any branches, to the matching
+OP_KET opcode. Each OP_ALT is followed by LINK_SIZE bytes giving the offset to
+the next one, or to the OP_KET opcode. For capturing brackets, the bracket 
+number is a count that immediately follows the offset.
+
+OP_KET is used for subpatterns that do not repeat indefinitely, and OP_KETRMIN
+and OP_KETRMAX are used for indefinite repetitions, minimally or maximally
+respectively (see below for possessive repetitions). All three are followed by
+LINK_SIZE bytes giving (as a positive number) the offset back to the matching
+bracket opcode.
+
+If a subpattern is quantified such that it is permitted to match zero times, it
+is preceded by one of OP_BRAZERO, OP_BRAMINZERO, or OP_SKIPZERO. These are
+single-unit opcodes that tell the matcher that skipping the following
+subpattern entirely is a valid branch. In the case of the first two, not 
+skipping the pattern is also valid (greedy and non-greedy). The third is used 
+when a pattern has the quantifier {0,0}. It cannot be entirely discarded,
+because it may be called as a subroutine from elsewhere in the regex.
+
+A subpattern with an indefinite maximum repetition is replicated in the
+compiled data its minimum number of times (or once with OP_BRAZERO if the
+minimum is zero), with the final copy terminating with OP_KETRMIN or OP_KETRMAX
+as appropriate.
+
+A subpattern with a bounded maximum repetition is replicated in a nested
+fashion up to the maximum number of times, with OP_BRAZERO or OP_BRAMINZERO
+before each replication after the minimum, so that, for example, (abc){2,5} is
+compiled as (abc)(abc)((abc)((abc)(abc)?)?)?, except that each bracketed group 
+has the same number.
+
+When a repeated subpattern has an unbounded upper limit, it is checked to see 
+whether it could match an empty string. If this is the case, the opcode in the 
+final replication is changed to OP_SBRA or OP_SCBRA. This tells the matcher
+that it needs to check for matching an empty string when it hits OP_KETRMIN or
+OP_KETRMAX, and if so, to break the loop.
+
+
+Possessive brackets
+-------------------
+
+When a repeated group (capturing or non-capturing) is marked as possessive by
+the "+" notation, e.g. (abc)++, different opcodes are used. Their names all
+have POS on the end, e.g. OP_BRAPOS instead of OP_BRA and OP_SCPBRPOS instead 
+of OP_SCBRA. The end of such a group is marked by OP_KETRPOS. If the minimum 
+repetition is zero, the group is preceded by OP_BRAPOSZERO.
+
+
+Once-only (atomic) groups
+-------------------------
+
+These are just like other subpatterns, but they start with the opcode
+OP_ONCE or OP_ONCE_NC. The former is used when there are no capturing brackets 
+within the atomic group; the latter when there are. The distinction is needed 
+for when there is a backtrack to before the group - any captures within the 
+group must be reset, so it is necessary to retain backtracking points inside
+the group even after it is complete in order to do this. When there are no 
+captures in an atomic group, all the backtracking can be discarded when it is 
+complete. This is more efficient, and also uses less stack.
+
+The check for matching an empty string in an unbounded repeat is handled
+entirely at runtime, so there are just these two opcodes for atomic groups.
+
+
+Assertions
+----------
+
+Forward assertions are also just like other subpatterns, but starting with one
+of the opcodes OP_ASSERT or OP_ASSERT_NOT. Backward assertions use the opcodes
+OP_ASSERTBACK and OP_ASSERTBACK_NOT, and the first opcode inside the assertion
+is OP_REVERSE, followed by a count of the number of characters to move back the
+pointer in the subject string. In ASCII mode, the count is a number of units,
+but in UTF-8/16 mode each character may occupy more than one unit; in UTF-32
+mode each character occupies exactly one unit. A separate count is present in
+each alternative of a lookbehind assertion, allowing them to have different
+fixed lengths.
+
+
+Conditional subpatterns
+-----------------------
+
+These are like other subpatterns, but they start with the opcode OP_COND, or
+OP_SCOND for one that might match an empty string in an unbounded repeat. If
+the condition is a back reference, this is stored at the start of the
+subpattern using the opcode OP_CREF followed by a count containing the
+reference number, provided that the reference is to a unique capturing group.
+If the reference was by name and there is more than one group with that name, 
+OP_DNCREF is used instead. It is followed by two counts: the index in the group 
+names table, and the number of groups with the same name.
+
+If the condition is "in recursion" (coded as "(?(R)"), or "in recursion of
+group x" (coded as "(?(Rx)"), the group number is stored at the start of the
+subpattern using the opcode OP_RREF (with a value of zero for "the whole
+pattern") or OP_DNRREF (with data as for OP_DNCREF). For a DEFINE condition,
+just the single unit OP_DEF is used (it has no associated data). Otherwise, a
+conditional subpattern always starts with one of the assertions.
+
+
+Recursion
+---------
+
+Recursion either matches the current regex, or some subexpression. The opcode
+OP_RECURSE is followed by aLINK_SIZE value that is the offset to the starting
+bracket from the start of the whole pattern. From release 6.5, OP_RECURSE is
+automatically wrapped inside OP_ONCE brackets, because otherwise some patterns
+broke it. OP_RECURSE is also used for "subroutine" calls, even though they are
+not strictly a recursion.
+
+
+Callout
+-------
+
+OP_CALLOUT is followed by one unit of data that holds a callout number in the
+range 0 to 254 for manual callouts, or 255 for an automatic callout. In both 
+cases there follows a count giving the offset in the pattern string to the
+start of the following item, and another count giving the length of this item.
+These values make is possible for pcretest to output useful tracing information 
+using automatic callouts.
+
+Philip Hazel
+November 2013
diff --git a/libs/Pcre16/docs/LICENCE b/libs/Pcre16/docs/LICENCE
new file mode 100644
index 0000000000..602e4ae680
--- /dev/null
+++ b/libs/Pcre16/docs/LICENCE
@@ -0,0 +1,92 @@
+PCRE LICENCE
+------------
+
+PCRE is a library of functions to support regular expressions whose syntax
+and semantics are as close as possible to those of the Perl 5 language.
+
+Release 8 of PCRE is distributed under the terms of the "BSD" licence, as
+specified below. The documentation for PCRE, supplied in the "doc"
+directory, is distributed under the same terms as the software itself.
+
+The basic library functions are written in C and are freestanding. Also
+included in the distribution is a set of C++ wrapper functions, and a
+just-in-time compiler that can be used to optimize pattern matching. These
+are both optional features that can be omitted when the library is built.
+
+
+THE BASIC LIBRARY FUNCTIONS
+---------------------------
+
+Written by:       Philip Hazel
+Email local part: ph10
+Email domain:     cam.ac.uk
+
+University of Cambridge Computing Service,
+Cambridge, England.
+
+Copyright (c) 1997-2014 University of Cambridge
+All rights reserved.
+
+
+PCRE JUST-IN-TIME COMPILATION SUPPORT
+-------------------------------------
+
+Written by:       Zoltan Herczeg
+Email local part: hzmester
+Emain domain:     freemail.hu
+
+Copyright(c) 2010-2014 Zoltan Herczeg
+All rights reserved.
+
+
+STACK-LESS JUST-IN-TIME COMPILER
+--------------------------------
+
+Written by:       Zoltan Herczeg
+Email local part: hzmester
+Emain domain:     freemail.hu
+
+Copyright(c) 2009-2014 Zoltan Herczeg
+All rights reserved.
+
+
+THE C++ WRAPPER FUNCTIONS
+-------------------------
+
+Contributed by:   Google Inc.
+
+Copyright (c) 2007-2012, Google Inc.
+All rights reserved.
+
+
+THE "BSD" LICENCE
+-----------------
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+    * Redistributions of source code must retain the above copyright notice,
+      this list of conditions and the following disclaimer.
+
+    * Redistributions in binary form must reproduce the above copyright
+      notice, this list of conditions and the following disclaimer in the
+      documentation and/or other materials provided with the distribution.
+
+    * Neither the name of the University of Cambridge nor the name of Google
+      Inc. nor the names of their contributors may be used to endorse or
+      promote products derived from this software without specific prior
+      written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.
+
+End
diff --git a/libs/Pcre16/docs/NEWS b/libs/Pcre16/docs/NEWS
new file mode 100644
index 0000000000..6331e9908d
--- /dev/null
+++ b/libs/Pcre16/docs/NEWS
@@ -0,0 +1,693 @@
+News about PCRE releases
+------------------------
+
+Release 8.35 04-April-2014
+--------------------------
+
+There have been performance improvements for classes containing non-ASCII
+characters and the "auto-possessification" feature has been extended. Other
+minor improvements have been implemented and bugs fixed. There is a new callout
+feature to enable applications to do detailed stack checks at compile time, to
+avoid running out of stack for deeply nested parentheses. The JIT compiler has
+been extended with experimental support for ARM-64, MIPS-64, and PPC-LE.
+
+
+Release 8.34 15-December-2013
+-----------------------------
+
+As well as fixing the inevitable bugs, performance has been improved by
+refactoring and extending the amount of "auto-possessification" that PCRE does.
+Other notable changes:
+
+.  Implemented PCRE_INFO_MATCH_EMPTY, which yields 1 if the pattern can match
+   an empty string. If it can, pcretest shows this in its information output.
+
+.  A back reference to a named subpattern when there is more than one of the
+   same name now checks them in the order in which they appear in the pattern.
+   The first one that is set is used for the reference. Previously only the
+   first one was inspected. This change makes PCRE more compatible with Perl.
+
+.  Unicode character properties were updated from Unicode 6.3.0.
+
+.  The character VT has been added to the set of characters that match \s and
+   are generally treated as white space, following this same change in Perl
+   5.18. There is now no difference between "Perl space" and "POSIX space".
+
+.  Perl has changed its handling of \8 and \9. If there is no previously
+   encountered capturing group of those numbers, they are treated as the
+   literal characters 8 and 9 instead of a binary zero followed by the
+   literals. PCRE now does the same.
+
+.  Following Perl, added \o{} to specify codepoints in octal, making it
+   possible to specify values greater than 0777 and also making them
+   unambiguous.
+
+.  In UCP mode, \s was not matching two of the characters that Perl matches,
+   namely NEL (U+0085) and MONGOLIAN VOWEL SEPARATOR (U+180E), though they
+   were matched by \h.
+
+.  Add JIT support for the 64 bit TileGX architecture.
+
+.  Upgraded the handling of the POSIX classes [:graph:], [:print:], and
+   [:punct:] when PCRE_UCP is set so as to include the same characters as Perl
+   does in Unicode mode.
+
+.  Perl no longer allows group names to start with digits, so I have made this
+   change also in PCRE.
+
+.  Added support for [[:<:]] and [[:>:]] as used in the BSD POSIX library to
+   mean "start of word" and "end of word", respectively, as a transition aid.
+
+
+Release 8.33 28-May-2013
+--------------------------
+
+A number of bugs are fixed, and some performance improvements have been made.
+There are also some new features, of which these are the most important:
+
+.  The behaviour of the backtracking verbs has been rationalized and
+   documented in more detail.
+
+.  JIT now supports callouts and all of the backtracking verbs.
+
+.  Unicode validation has been updated in the light of Unicode Corrigendum #9,
+   which points out that "non characters" are not "characters that may not
+   appear in Unicode strings" but rather "characters that are reserved for
+   internal use and have only local meaning".
+
+.  (*LIMIT_MATCH=d) and (*LIMIT_RECURSION=d) have been added so that the
+   creator of a pattern can specify lower (but not higher) limits for the
+   matching process.
+
+.  The PCRE_NEVER_UTF option is available to prevent pattern-writers from using
+   the (*UTF) feature, as this could be a security issue.
+
+
+Release 8.32 30-November-2012
+-----------------------------
+
+This release fixes a number of bugs, but also has some new features. These are
+the highlights:
+
+.  There is now support for 32-bit character strings and UTF-32. Like the
+   16-bit support, this is done by compiling a separate 32-bit library.
+
+.  \X now matches a Unicode extended grapheme cluster.
+
+.  Case-independent matching of Unicode characters that have more than one
+   "other case" now makes all three (or more) characters equivalent. This
+   applies, for example, to Greek Sigma, which has two lowercase versions.
+
+.  Unicode character properties are updated to Unicode 6.2.0.
+
+.  The EBCDIC support, which had decayed, has had a spring clean.
+
+.  A number of JIT optimizations have been added, which give faster JIT
+   execution speed. In addition, a new direct interface to JIT execution is
+   available. This bypasses some of the sanity checks of pcre_exec() to give a
+   noticeable speed-up.
+
+.  A number of issues in pcregrep have been fixed, making it more compatible
+   with GNU grep. In particular, --exclude and --include (and variants) apply
+   to all files now, not just those obtained from scanning a directory
+   recursively. In Windows environments, the default action for directories is
+   now "skip" instead of "read" (which provokes an error).
+
+.  If the --only-matching (-o) option in pcregrep is specified multiple
+   times, each one causes appropriate output. For example, -o1 -o2 outputs the
+   substrings matched by the 1st and 2nd capturing parentheses. A separating
+   string can be specified by --om-separator (default empty).
+
+.  When PCRE is built via Autotools using a version of gcc that has the
+   "visibility" feature, it is used to hide internal library functions that are
+   not part of the public API.
+
+
+Release 8.31 06-July-2012
+-------------------------
+
+This is mainly a bug-fixing release, with a small number of developments:
+
+. The JIT compiler now supports partial matching and the (*MARK) and
+  (*COMMIT) verbs.
+
+. PCRE_INFO_MAXLOOKBEHIND can be used to find the longest lookbehind in a
+  pattern.
+
+. There should be a performance improvement when using the heap instead of the
+  stack for recursion.
+
+. pcregrep can now be linked with libedit as an alternative to libreadline.
+
+. pcregrep now has a --file-list option where the list of files to scan is
+  given as a file.
+
+. pcregrep now recognizes binary files and there are related options.
+
+. The Unicode tables have been updated to 6.1.0.
+
+As always, the full list of changes is in the ChangeLog file.
+
+
+Release 8.30 04-February-2012
+-----------------------------
+
+Release 8.30 introduces a major new feature: support for 16-bit character
+strings, compiled as a separate library. There are a few changes to the
+8-bit library, in addition to some bug fixes.
+
+. The pcre_info() function, which has been obsolete for over 10 years, has
+  been removed.
+
+. When a compiled pattern was saved to a file and later reloaded on a host
+  with different endianness, PCRE used automatically to swap the bytes in some
+  of the data fields. With the advent of the 16-bit library, where more of this
+  swapping is needed, it is no longer done automatically. Instead, the bad
+  endianness is detected and a specific error is given. The user can then call
+  a new function called pcre_pattern_to_host_byte_order() (or an equivalent
+  16-bit function) to do the swap.
+
+. In UTF-8 mode, the values 0xd800 to 0xdfff are not legal Unicode
+  code points and are now faulted. (They are the so-called "surrogates"
+  that are reserved for coding high values in UTF-16.)
+
+
+Release 8.21 12-Dec-2011
+------------------------
+
+This is almost entirely a bug-fix release. The only new feature is the ability
+to obtain the size of the memory used by the JIT compiler.
+
+
+Release 8.20 21-Oct-2011
+------------------------
+
+The main change in this release is the inclusion of Zoltan Herczeg's
+just-in-time compiler support, which can be accessed by building PCRE with
+--enable-jit. Large performance benefits can be had in many situations. 8.20
+also fixes an unfortunate bug that was introduced in 8.13 as well as tidying up
+a number of infelicities and differences from Perl.
+
+
+Release 8.13 16-Aug-2011
+------------------------
+
+This is mainly a bug-fix release. There has been a lot of internal refactoring.
+The Unicode tables have been updated. The only new feature in the library is
+the passing of *MARK information to callouts. Some additions have been made to
+pcretest to make testing easier and more comprehensive. There is a new option
+for pcregrep to adjust its internal buffer size.
+
+
+Release 8.12 15-Jan-2011
+------------------------
+
+This release fixes some bugs in pcregrep, one of which caused the tests to fail
+on 64-bit big-endian systems. There are no changes to the code of the library.
+
+
+Release 8.11 10-Dec-2010
+------------------------
+
+A number of bugs in the library and in pcregrep have been fixed. As always, see
+ChangeLog for details. The following are the non-bug-fix changes:
+
+. Added --match-limit and --recursion-limit to pcregrep.
+
+. Added an optional parentheses number to the -o and --only-matching options
+  of pcregrep.
+
+. Changed the way PCRE_PARTIAL_HARD affects the matching of $, \z, \Z, \b, and
+  \B.
+
+. Added PCRE_ERROR_SHORTUTF8 to make it possible to distinguish between a
+  bad UTF-8 sequence and one that is incomplete when using PCRE_PARTIAL_HARD.
+
+. Recognize (*NO_START_OPT) at the start of a pattern to set the PCRE_NO_
+  START_OPTIMIZE option, which is now allowed at compile time
+
+
+Release 8.10 25-Jun-2010
+------------------------
+
+There are two major additions: support for (*MARK) and friends, and the option
+PCRE_UCP, which changes the behaviour of \b, \d, \s, and \w (and their
+opposites) so that they make use of Unicode properties. There are also a number
+of lesser new features, and several bugs have been fixed. A new option,
+--line-buffered, has been added to pcregrep, for use when it is connected to
+pipes.
+
+
+Release 8.02 19-Mar-2010
+------------------------
+
+Another bug-fix release.
+
+
+Release 8.01 19-Jan-2010
+------------------------
+
+This is a bug-fix release. Several bugs in the code itself and some bugs and
+infelicities in the build system have been fixed.
+
+
+Release 8.00 19-Oct-09
+----------------------
+
+Bugs have been fixed in the library and in pcregrep. There are also some
+enhancements. Restrictions on patterns used for partial matching have been
+removed, extra information is given for partial matches, the partial matching
+process has been improved, and an option to make a partial match override a
+full match is available. The "study" process has been enhanced by finding a
+lower bound matching length. Groups with duplicate numbers may now have
+duplicated names without the use of PCRE_DUPNAMES. However, they may not have
+different names. The documentation has been revised to reflect these changes.
+The version number has been expanded to 3 digits as it is clear that the rate
+of change is not slowing down.
+
+
+Release 7.9 11-Apr-09
+---------------------
+
+Mostly bugfixes and tidies with just a couple of minor functional additions.
+
+
+Release 7.8 05-Sep-08
+---------------------
+
+More bug fixes, plus a performance improvement in Unicode character property
+lookup.
+
+
+Release 7.7 07-May-08
+---------------------
+
+This is once again mainly a bug-fix release, but there are a couple of new
+features.
+
+
+Release 7.6 28-Jan-08
+---------------------
+
+The main reason for having this release so soon after 7.5 is because it fixes a
+potential buffer overflow problem in pcre_compile() when run in UTF-8 mode. In
+addition, the CMake configuration files have been brought up to date.
+
+
+Release 7.5 10-Jan-08
+---------------------
+
+This is mainly a bug-fix release. However the ability to link pcregrep with
+libz or libbz2 and the ability to link pcretest with libreadline have been
+added. Also the --line-offsets and --file-offsets options were added to
+pcregrep.
+
+
+Release 7.4 21-Sep-07
+---------------------
+
+The only change of specification is the addition of options to control whether
+\R matches any Unicode line ending (the default) or just CR, LF, and CRLF.
+Otherwise, the changes are bug fixes and a refactoring to reduce the number of
+relocations needed in a shared library. There have also been some documentation
+updates, in particular, some more information about using CMake to build PCRE
+has been added to the NON-UNIX-USE file.
+
+
+Release 7.3 28-Aug-07
+---------------------
+
+Most changes are bug fixes. Some that are not:
+
+1. There is some support for Perl 5.10's experimental "backtracking control
+   verbs" such as (*PRUNE).
+
+2. UTF-8 checking is now as per RFC 3629 instead of RFC 2279; this is more
+   restrictive in the strings it accepts.
+
+3. Checking for potential integer overflow has been made more dynamic, and as a
+   consequence there is no longer a hard limit on the size of a subpattern that
+   has a limited repeat count.
+
+4. When CRLF is a valid line-ending sequence, pcre_exec() and pcre_dfa_exec()
+   no longer advance by two characters instead of one when an unanchored match
+   fails at CRLF if there are explicit CR or LF matches within the pattern.
+   This gets rid of some anomalous effects that previously occurred.
+
+5. Some PCRE-specific settings for varying the newline options at the start of
+   a pattern have been added.
+
+
+Release 7.2 19-Jun-07
+---------------------
+
+WARNING: saved patterns that were compiled by earlier versions of PCRE must be
+recompiled for use with 7.2 (necessitated by the addition of \K, \h, \H, \v,
+and \V).
+
+Correction to the notes for 7.1: the note about shared libraries for Windows is
+wrong. Previously, three libraries were built, but each could function
+independently. For example, the pcreposix library also included all the
+functions from the basic pcre library. The change is that the three libraries
+are no longer independent. They are like the Unix libraries. To use the
+pcreposix functions, for example, you need to link with both the pcreposix and
+the basic pcre library.
+
+Some more features from Perl 5.10 have been added:
+
+  (?-n) and (?+n) relative references for recursion and subroutines.
+
+  (?(-n) and (?(+n) relative references as conditions.
+
+  \k{name} and \g{name} are synonyms for \k<name>.
+
+  \K to reset the start of the matched string; for example, (foo)\Kbar
+  matches bar preceded by foo, but only sets bar as the matched string.
+
+  (?| introduces a group where the capturing parentheses in each alternative
+  start from the same number; for example, (?|(abc)|(xyz)) sets capturing
+  parentheses number 1 in both cases.
+
+  \h, \H, \v, \V match horizontal and vertical whitespace, respectively.
+
+
+Release 7.1 24-Apr-07
+---------------------
+
+There is only one new feature in this release: a linebreak setting of
+PCRE_NEWLINE_ANYCRLF. It is a cut-down version of PCRE_NEWLINE_ANY, which
+recognizes only CRLF, CR, and LF as linebreaks.
+
+A few bugs are fixed (see ChangeLog for details), but the major change is a
+complete re-implementation of the build system. This now has full Autotools
+support and so is now "standard" in some sense. It should help with compiling
+PCRE in a wide variety of environments.
+
+NOTE: when building shared libraries for Windows, three dlls are now built,
+called libpcre, libpcreposix, and libpcrecpp. Previously, everything was
+included in a single dll.
+
+Another important change is that the dftables auxiliary program is no longer
+compiled and run at "make" time by default. Instead, a default set of character
+tables (assuming ASCII coding) is used. If you want to use dftables to generate
+the character tables as previously, add --enable-rebuild-chartables to the
+"configure" command. You must do this if you are compiling PCRE to run on a
+system that uses EBCDIC code.
+
+There is a discussion about character tables in the README file. The default is
+not to use dftables so that that there is no problem when cross-compiling.
+
+
+Release 7.0 19-Dec-06
+---------------------
+
+This release has a new major number because there have been some internal
+upheavals to facilitate the addition of new optimizations and other facilities,
+and to make subsequent maintenance and extension easier. Compilation is likely
+to be a bit slower, but there should be no major effect on runtime performance.
+Previously compiled patterns are NOT upwards compatible with this release. If
+you have saved compiled patterns from a previous release, you will have to
+re-compile them. Important changes that are visible to users are:
+
+1. The Unicode property tables have been updated to Unicode 5.0.0, which adds
+   some more scripts.
+
+2. The option PCRE_NEWLINE_ANY causes PCRE to recognize any Unicode newline
+   sequence as a newline.
+
+3. The \R escape matches a single Unicode newline sequence as a single unit.
+
+4. New features that will appear in Perl 5.10 are now in PCRE. These include
+   alternative Perl syntax for named parentheses, and Perl syntax for
+   recursion.
+
+5. The C++ wrapper interface has been extended by the addition of a
+   QuoteMeta function and the ability to allow copy construction and
+   assignment.
+
+For a complete list of changes, see the ChangeLog file.
+
+
+Release 6.7 04-Jul-06
+---------------------
+
+The main additions to this release are the ability to use the same name for
+multiple sets of parentheses, and support for CRLF line endings in both the
+library and pcregrep (and in pcretest for testing).
+
+Thanks to Ian Taylor, the stack usage for many kinds of pattern has been
+significantly reduced for certain subject strings.
+
+
+Release 6.5 01-Feb-06
+---------------------
+
+Important changes in this release:
+
+1. A number of new features have been added to pcregrep.
+
+2. The Unicode property tables have been updated to Unicode 4.1.0, and the
+   supported properties have been extended with script names such as "Arabic",
+   and the derived properties "Any" and "L&". This has necessitated a change to
+   the interal format of compiled patterns. Any saved compiled patterns that
+   use \p or \P must be recompiled.
+
+3. The specification of recursion in patterns has been changed so that all
+   recursive subpatterns are automatically treated as atomic groups. Thus, for
+   example, (?R) is treated as if it were (?>(?R)). This is necessary because
+   otherwise there are situations where recursion does not work.
+
+See the ChangeLog for a complete list of changes, which include a number of bug
+fixes and tidies.
+
+
+Release 6.0 07-Jun-05
+---------------------
+
+The release number has been increased to 6.0 because of the addition of several
+major new pieces of functionality.
+
+A new function, pcre_dfa_exec(), which implements pattern matching using a DFA
+algorithm, has been added. This has a number of advantages for certain cases,
+though it does run more slowly, and lacks the ability to capture substrings. On
+the other hand, it does find all matches, not just the first, and it works
+better for partial matching. The pcrematching man page discusses the
+differences.
+
+The pcretest program has been enhanced so that it can make use of the new
+pcre_dfa_exec() matching function and the extra features it provides.
+
+The distribution now includes a C++ wrapper library. This is built
+automatically if a C++ compiler is found. The pcrecpp man page discusses this
+interface.
+
+The code itself has been re-organized into many more files, one for each
+function, so it no longer requires everything to be linked in when static
+linkage is used. As a consequence, some internal functions have had to have
+their names exposed. These functions all have names starting with _pcre_. They
+are undocumented, and are not intended for use by outside callers.
+
+The pcregrep program has been enhanced with new functionality such as
+multiline-matching and options for output more matching context. See the
+ChangeLog for a complete list of changes to the library and the utility
+programs.
+
+
+Release 5.0 13-Sep-04
+---------------------
+
+The licence under which PCRE is released has been changed to the more
+conventional "BSD" licence.
+
+In the code, some bugs have been fixed, and there are also some major changes
+in this release (which is why I've increased the number to 5.0). Some changes
+are internal rearrangements, and some provide a number of new facilities. The
+new features are:
+
+1. There's an "automatic callout" feature that inserts callouts before every
+   item in the regex, and there's a new callout field that gives the position
+   in the pattern - useful for debugging and tracing.
+
+2. The extra_data structure can now be used to pass in a set of character
+   tables at exec time. This is useful if compiled regex are saved and re-used
+   at a later time when the tables may not be at the same address. If the
+   default internal tables are used, the pointer saved with the compiled
+   pattern is now set to NULL, which means that you don't need to do anything
+   special unless you are using custom tables.
+
+3. It is possible, with some restrictions on the content of the regex, to
+   request "partial" matching. A special return code is given if all of the
+   subject string matched part of the regex. This could be useful for testing
+   an input field as it is being typed.
+
+4. There is now some optional support for Unicode character properties, which
+   means that the patterns items such as \p{Lu} and \X can now be used. Only
+   the general category properties are supported. If PCRE is compiled with this
+   support, an additional 90K data structure is include, which increases the
+   size of the library dramatically.
+
+5. There is support for saving compiled patterns and re-using them later.
+
+6. There is support for running regular expressions that were compiled on a
+   different host with the opposite endianness.
+
+7. The pcretest program has been extended to accommodate the new features.
+
+The main internal rearrangement is that sequences of literal characters are no
+longer handled as strings. Instead, each character is handled on its own. This
+makes some UTF-8 handling easier, and makes the support of partial matching
+possible. Compiled patterns containing long literal strings will be larger as a
+result of this change; I hope that performance will not be much affected.
+
+
+Release 4.5 01-Dec-03
+---------------------
+
+Again mainly a bug-fix and tidying release, with only a couple of new features:
+
+1. It's possible now to compile PCRE so that it does not use recursive
+function calls when matching. Instead it gets memory from the heap. This slows
+things down, but may be necessary on systems with limited stacks.
+
+2. UTF-8 string checking has been tightened to reject overlong sequences and to
+check that a starting offset points to the start of a character. Failure of the
+latter returns a new error code: PCRE_ERROR_BADUTF8_OFFSET.
+
+3. PCRE can now be compiled for systems that use EBCDIC code.
+
+
+Release 4.4 21-Aug-03
+---------------------
+
+This is mainly a bug-fix and tidying release. The only new feature is that PCRE
+checks UTF-8 strings for validity by default. There is an option to suppress
+this, just in case anybody wants that teeny extra bit of performance.
+
+
+Releases 4.1 - 4.3
+------------------
+
+Sorry, I forgot about updating the NEWS file for these releases. Please take a
+look at ChangeLog.
+
+
+Release 4.0 17-Feb-03
+---------------------
+
+There have been a lot of changes for the 4.0 release, adding additional
+functionality and mending bugs. Below is a list of the highlights of the new
+functionality. For full details of these features, please consult the
+documentation. For a complete list of changes, see the ChangeLog file.
+
+1. Support for Perl's \Q...\E escapes.
+
+2. "Possessive quantifiers" ?+, *+, ++, and {,}+ which come from Sun's Java
+package. They provide some syntactic sugar for simple cases of "atomic
+grouping".
+
+3. Support for the \G assertion. It is true when the current matching position
+is at the start point of the match.
+
+4. A new feature that provides some of the functionality that Perl provides
+with (?{...}). The facility is termed a "callout". The way it is done in PCRE
+is for the caller to provide an optional function, by setting pcre_callout to
+its entry point. To get the function called, the regex must include (?C) at
+appropriate points.
+
+5. Support for recursive calls to individual subpatterns. This makes it really
+easy to get totally confused.
+
+6. Support for named subpatterns. The Python syntax (?P<name>...) is used to
+name a group.
+
+7. Several extensions to UTF-8 support; it is now fairly complete. There is an
+option for pcregrep to make it operate in UTF-8 mode.
+
+8. The single man page has been split into a number of separate man pages.
+These also give rise to individual HTML pages which are put in a separate
+directory. There is an index.html page that lists them all. Some hyperlinking
+between the pages has been installed.
+
+
+Release 3.5 15-Aug-01
+---------------------
+
+1. The configuring system has been upgraded to use later versions of autoconf
+and libtool. By default it builds both a shared and a static library if the OS
+supports it. You can use --disable-shared or --disable-static on the configure
+command if you want only one of them.
+
+2. The pcretest utility is now installed along with pcregrep because it is
+useful for users (to test regexs) and by doing this, it automatically gets
+relinked by libtool. The documentation has been turned into a man page, so
+there are now .1, .txt, and .html versions in /doc.
+
+3. Upgrades to pcregrep:
+   (i)   Added long-form option names like gnu grep.
+   (ii)  Added --help to list all options with an explanatory phrase.
+   (iii) Added -r, --recursive to recurse into sub-directories.
+   (iv)  Added -f, --file to read patterns from a file.
+
+4. Added --enable-newline-is-cr and --enable-newline-is-lf to the configure
+script, to force use of CR or LF instead of \n in the source. On non-Unix
+systems, the value can be set in config.h.
+
+5. The limit of 200 on non-capturing parentheses is a _nesting_ limit, not an
+absolute limit. Changed the text of the error message to make this clear, and
+likewise updated the man page.
+
+6. The limit of 99 on the number of capturing subpatterns has been removed.
+The new limit is 65535, which I hope will not be a "real" limit.
+
+
+Release 3.3 01-Aug-00
+---------------------
+
+There is some support for UTF-8 character strings. This is incomplete and
+experimental. The documentation describes what is and what is not implemented.
+Otherwise, this is just a bug-fixing release.
+
+
+Release 3.0 01-Feb-00
+---------------------
+
+1. A "configure" script is now used to configure PCRE for Unix systems. It
+builds a Makefile, a config.h file, and the pcre-config script.
+
+2. PCRE is built as a shared library by default.
+
+3. There is support for POSIX classes such as [:alpha:].
+
+5. There is an experimental recursion feature.
+
+----------------------------------------------------------------------------
+          IMPORTANT FOR THOSE UPGRADING FROM VERSIONS BEFORE 2.00
+
+Please note that there has been a change in the API such that a larger
+ovector is required at matching time, to provide some additional workspace.
+The new man page has details. This change was necessary in order to support
+some of the new functionality in Perl 5.005.
+
+          IMPORTANT FOR THOSE UPGRADING FROM VERSION 2.00
+
+Another (I hope this is the last!) change has been made to the API for the
+pcre_compile() function. An additional argument has been added to make it
+possible to pass over a pointer to character tables built in the current
+locale by pcre_maketables(). To use the default tables, this new argument
+should be passed as NULL.
+
+          IMPORTANT FOR THOSE UPGRADING FROM VERSION 2.05
+
+Yet another (and again I hope this really is the last) change has been made
+to the API for the pcre_exec() function. An additional argument has been
+added to make it possible to start the match other than at the start of the
+subject string. This is important if there are lookbehinds. The new man
+page has the details, but you just want to convert existing programs, all
+you need to do is to stick in a new fifth argument to pcre_exec(), with a
+value of zero. For example, change
+
+  pcre_exec(pattern, extra, subject, length, options, ovec, ovecsize)
+to
+  pcre_exec(pattern, extra, subject, length, 0, options, ovec, ovecsize)
+
+****
diff --git a/libs/Pcre16/docs/NON-AUTOTOOLS-BUILD b/libs/Pcre16/docs/NON-AUTOTOOLS-BUILD
new file mode 100644
index 0000000000..cddf3e0699
--- /dev/null
+++ b/libs/Pcre16/docs/NON-AUTOTOOLS-BUILD
@@ -0,0 +1,764 @@
+Building PCRE without using autotools
+-------------------------------------
+
+This document contains the following sections:
+
+  General
+  Generic instructions for the PCRE C library
+  The C++ wrapper functions
+  Building for virtual Pascal
+  Stack size in Windows environments
+  Linking programs in Windows environments
+  Calling conventions in Windows environments
+  Comments about Win32 builds
+  Building PCRE on Windows with CMake
+  Use of relative paths with CMake on Windows
+  Testing with RunTest.bat
+  Building under Windows CE with Visual Studio 200x
+  Building under Windows with BCC5.5
+  Building using Borland C++ Builder 2007 (CB2007) and higher
+  Building PCRE on OpenVMS
+  Building PCRE on Stratus OpenVOS
+  Building PCRE on native z/OS and z/VM
+
+
+GENERAL
+
+I (Philip Hazel) have no experience of Windows or VMS sytems and how their
+libraries work. The items in the PCRE distribution and Makefile that relate to
+anything other than Linux systems are untested by me.
+
+There are some other comments and files (including some documentation in CHM
+format) in the Contrib directory on the FTP site:
+
+  ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre/Contrib
+
+The basic PCRE library consists entirely of code written in Standard C, and so
+should compile successfully on any system that has a Standard C compiler and
+library. The C++ wrapper functions are a separate issue (see below).
+
+The PCRE distribution includes a "configure" file for use by the configure/make
+(autotools) build system, as found in many Unix-like environments. The README
+file contains information about the options for "configure".
+
+There is also support for CMake, which some users prefer, especially in Windows
+environments, though it can also be run in Unix-like environments. See the
+section entitled "Building PCRE on Windows with CMake" below.
+
+Versions of config.h and pcre.h are distributed in the PCRE tarballs under the
+names config.h.generic and pcre.h.generic. These are provided for those who
+build PCRE without using "configure" or CMake. If you use "configure" or CMake,
+the .generic versions are not used.
+
+
+GENERIC INSTRUCTIONS FOR THE PCRE C LIBRARY
+
+The following are generic instructions for building the PCRE C library "by
+hand". If you are going to use CMake, this section does not apply to you; you
+can skip ahead to the CMake section.
+
+ (1) Copy or rename the file config.h.generic as config.h, and edit the macro
+     settings that it contains to whatever is appropriate for your environment.
+
+     In particular, you can alter the definition of the NEWLINE macro to
+     specify what character(s) you want to be interpreted as line terminators.
+     In an EBCDIC environment, you MUST change NEWLINE, because its default
+     value is 10, an ASCII LF. The usual EBCDIC newline character is 21 (0x15,
+     NL), though in some cases it may be 37 (0x25).
+
+     When you compile any of the PCRE modules, you must specify -DHAVE_CONFIG_H
+     to your compiler so that config.h is included in the sources.
+
+     An alternative approach is not to edit config.h, but to use -D on the
+     compiler command line to make any changes that you need to the
+     configuration options. In this case -DHAVE_CONFIG_H must not be set.
+
+     NOTE: There have been occasions when the way in which certain parameters
+     in config.h are used has changed between releases. (In the configure/make
+     world, this is handled automatically.) When upgrading to a new release,
+     you are strongly advised to review config.h.generic before re-using what
+     you had previously.
+
+ (2) Copy or rename the file pcre.h.generic as pcre.h.
+
+ (3) EITHER:
+       Copy or rename file pcre_chartables.c.dist as pcre_chartables.c.
+
+     OR:
+       Compile dftables.c as a stand-alone program (using -DHAVE_CONFIG_H if
+       you have set up config.h), and then run it with the single argument
+       "pcre_chartables.c". This generates a set of standard character tables
+       and writes them to that file. The tables are generated using the default
+       C locale for your system. If you want to use a locale that is specified
+       by LC_xxx environment variables, add the -L option to the dftables
+       command. You must use this method if you are building on a system that
+       uses EBCDIC code.
+
+     The tables in pcre_chartables.c are defaults. The caller of PCRE can
+     specify alternative tables at run time.
+
+ (4) Ensure that you have the following header files:
+
+       pcre_internal.h
+       ucp.h
+
+ (5) For an 8-bit library, compile the following source files, setting
+     -DHAVE_CONFIG_H as a compiler option if you have set up config.h with your
+     configuration, or else use other -D settings to change the configuration
+     as required.
+
+       pcre_byte_order.c
+       pcre_chartables.c
+       pcre_compile.c
+       pcre_config.c
+       pcre_dfa_exec.c
+       pcre_exec.c
+       pcre_fullinfo.c
+       pcre_get.c
+       pcre_globals.c
+       pcre_jit_compile.c
+       pcre_maketables.c
+       pcre_newline.c
+       pcre_ord2utf8.c
+       pcre_refcount.c
+       pcre_string_utils.c
+       pcre_study.c
+       pcre_tables.c
+       pcre_ucd.c
+       pcre_valid_utf8.c
+       pcre_version.c
+       pcre_xclass.c
+
+     Make sure that you include -I. in the compiler command (or equivalent for
+     an unusual compiler) so that all included PCRE header files are first
+     sought in the current directory. Otherwise you run the risk of picking up
+     a previously-installed file from somewhere else.
+
+     Note that you must still compile pcre_jit_compile.c, even if you have not
+     defined SUPPORT_JIT in config.h, because when JIT support is not
+     configured, dummy functions are compiled. When JIT support IS configured,
+     pcre_jit_compile.c #includes sources from the sljit subdirectory, where
+     there should be 16 files, all of whose names begin with "sljit".
+
+ (6) Now link all the compiled code into an object library in whichever form
+     your system keeps such libraries. This is the basic PCRE C 8-bit library.
+     If your system has static and shared libraries, you may have to do this
+     once for each type.
+
+ (7) If you want to build a 16-bit library (as well as, or instead of the 8-bit
+     or 32-bit libraries) repeat steps 5-6 with the following files:
+
+       pcre16_byte_order.c
+       pcre16_chartables.c
+       pcre16_compile.c
+       pcre16_config.c
+       pcre16_dfa_exec.c
+       pcre16_exec.c
+       pcre16_fullinfo.c
+       pcre16_get.c
+       pcre16_globals.c
+       pcre16_jit_compile.c
+       pcre16_maketables.c
+       pcre16_newline.c
+       pcre16_ord2utf16.c
+       pcre16_refcount.c
+       pcre16_string_utils.c
+       pcre16_study.c
+       pcre16_tables.c
+       pcre16_ucd.c
+       pcre16_utf16_utils.c
+       pcre16_valid_utf16.c
+       pcre16_version.c
+       pcre16_xclass.c
+
+ (8) If you want to build a 32-bit library (as well as, or instead of the 8-bit
+     or 16-bit libraries) repeat steps 5-6 with the following files:
+
+       pcre32_byte_order.c
+       pcre32_chartables.c
+       pcre32_compile.c
+       pcre32_config.c
+       pcre32_dfa_exec.c
+       pcre32_exec.c
+       pcre32_fullinfo.c
+       pcre32_get.c
+       pcre32_globals.c
+       pcre32_jit_compile.c
+       pcre32_maketables.c
+       pcre32_newline.c
+       pcre32_ord2utf32.c
+       pcre32_refcount.c
+       pcre32_string_utils.c
+       pcre32_study.c
+       pcre32_tables.c
+       pcre32_ucd.c
+       pcre32_utf32_utils.c
+       pcre32_valid_utf32.c
+       pcre32_version.c
+       pcre32_xclass.c
+
+ (9) If you want to build the POSIX wrapper functions (which apply only to the
+     8-bit library), ensure that you have the pcreposix.h file and then compile
+     pcreposix.c (remembering -DHAVE_CONFIG_H if necessary). Link the result
+     (on its own) as the pcreposix library.
+
+(10) The pcretest program can be linked with any combination of the 8-bit,
+     16-bit and 32-bit libraries (depending on what you selected in config.h).
+     Compile pcretest.c and pcre_printint.c (again, don't forget
+     -DHAVE_CONFIG_H) and link them together with the appropriate library/ies.
+     If you compiled an 8-bit library, pcretest also needs the pcreposix
+     wrapper library unless you compiled it with -DNOPOSIX.
+
+(11) Run pcretest on the testinput files in the testdata directory, and check
+     that the output matches the corresponding testoutput files. There are
+     comments about what each test does in the section entitled "Testing PCRE"
+     in the README file. If you compiled more than one of the 8-bit, 16-bit and
+     32-bit libraries, you need to run pcretest with the -16 option to do
+     16-bit tests and with the -32 option to do 32-bit tests.
+
+     Some tests are relevant only when certain build-time options are selected.
+     For example, test 4 is for UTF-8/UTF-16/UTF-32 support, and will not run
+     if you have built PCRE without it. See the comments at the start of each
+     testinput file. If you have a suitable Unix-like shell, the RunTest script
+     will run the appropriate tests for you. The command "RunTest list" will
+     output a list of all the tests.
+
+     Note that the supplied files are in Unix format, with just LF characters
+     as line terminators. You may need to edit them to change this if your
+     system uses a different convention. If you are using Windows, you probably
+     should use the wintestinput3 file instead of testinput3 (and the
+     corresponding output file). This is a locale test; wintestinput3 sets the
+     locale to "french" rather than "fr_FR", and there some minor output
+     differences.
+
+(12) If you have built PCRE with SUPPORT_JIT, the JIT features will be tested
+     by the testdata files. However, you might also like to build and run
+     the freestanding JIT test program, pcre_jit_test.c.
+
+(13) If you want to use the pcregrep command, compile and link pcregrep.c; it
+     uses only the basic 8-bit PCRE library (it does not need the pcreposix
+     library).
+
+
+THE C++ WRAPPER FUNCTIONS
+
+The PCRE distribution also contains some C++ wrapper functions and tests,
+applicable to the 8-bit library, which were contributed by Google Inc. On a
+system that can use "configure" and "make", the functions are automatically
+built into a library called pcrecpp. It should be straightforward to compile
+the .cc files manually on other systems. The files called xxx_unittest.cc are
+test programs for each of the corresponding xxx.cc files.
+
+
+BUILDING FOR VIRTUAL PASCAL
+
+A script for building PCRE using Borland's C++ compiler for use with VPASCAL
+was contributed by Alexander Tokarev. Stefan Weber updated the script and added
+additional files. The following files in the distribution are for building PCRE
+for use with VP/Borland: makevp_c.txt, makevp_l.txt, makevp.bat, pcregexp.pas.
+
+
+STACK SIZE IN WINDOWS ENVIRONMENTS
+
+The default processor stack size of 1Mb in some Windows environments is too
+small for matching patterns that need much recursion. In particular, test 2 may
+fail because of this. Normally, running out of stack causes a crash, but there
+have been cases where the test program has just died silently. See your linker
+documentation for how to increase stack size if you experience problems. The
+Linux default of 8Mb is a reasonable choice for the stack, though even that can
+be too small for some pattern/subject combinations.
+
+PCRE has a compile configuration option to disable the use of stack for
+recursion so that heap is used instead. However, pattern matching is
+significantly slower when this is done. There is more about stack usage in the
+"pcrestack" documentation.
+
+
+LINKING PROGRAMS IN WINDOWS ENVIRONMENTS
+
+If you want to statically link a program against a PCRE library in the form of
+a non-dll .a file, you must define PCRE_STATIC before including pcre.h or
+pcrecpp.h, otherwise the pcre_malloc() and pcre_free() exported functions will
+be declared __declspec(dllimport), with unwanted results.
+
+
+CALLING CONVENTIONS IN WINDOWS ENVIRONMENTS
+
+It is possible to compile programs to use different calling conventions using
+MSVC. Search the web for "calling conventions" for more information. To make it
+easier to change the calling convention for the exported functions in the
+PCRE library, the macro PCRE_CALL_CONVENTION is present in all the external
+definitions. It can be set externally when compiling (e.g. in CFLAGS). If it is
+not set, it defaults to empty; the default calling convention is then used
+(which is what is wanted most of the time).
+
+
+COMMENTS ABOUT WIN32 BUILDS (see also "BUILDING PCRE ON WINDOWS WITH CMAKE")
+
+There are two ways of building PCRE using the "configure, make, make install"
+paradigm on Windows systems: using MinGW or using Cygwin. These are not at all
+the same thing; they are completely different from each other. There is also
+support for building using CMake, which some users find a more straightforward
+way of building PCRE under Windows.
+
+The MinGW home page (http://www.mingw.org/) says this:
+
+  MinGW: A collection of freely available and freely distributable Windows
+  specific header files and import libraries combined with GNU toolsets that
+  allow one to produce native Windows programs that do not rely on any
+  3rd-party C runtime DLLs.
+
+The Cygwin home page (http://www.cygwin.com/) says this:
+
+  Cygwin is a Linux-like environment for Windows. It consists of two parts:
+
+  . A DLL (cygwin1.dll) which acts as a Linux API emulation layer providing
+    substantial Linux API functionality
+
+  . A collection of tools which provide Linux look and feel.
+
+  The Cygwin DLL currently works with all recent, commercially released x86 32
+  bit and 64 bit versions of Windows, with the exception of Windows CE.
+
+On both MinGW and Cygwin, PCRE should build correctly using:
+
+  ./configure && make && make install
+
+This should create two libraries called libpcre and libpcreposix, and, if you
+have enabled building the C++ wrapper, a third one called libpcrecpp. These are
+independent libraries: when you link with libpcreposix or libpcrecpp you must
+also link with libpcre, which contains the basic functions. (Some earlier
+releases of PCRE included the basic libpcre functions in libpcreposix. This no
+longer happens.)
+
+A user submitted a special-purpose patch that makes it easy to create
+"pcre.dll" under mingw32 using the "msys" environment. It provides "pcre.dll"
+as a special target. If you use this target, no other files are built, and in
+particular, the pcretest and pcregrep programs are not built. An example of how
+this might be used is:
+
+  ./configure --enable-utf --disable-cpp CFLAGS="-03 -s"; make pcre.dll
+
+Using Cygwin's compiler generates libraries and executables that depend on
+cygwin1.dll. If a library that is generated this way is distributed,
+cygwin1.dll has to be distributed as well. Since cygwin1.dll is under the GPL
+licence, this forces not only PCRE to be under the GPL, but also the entire
+application. A distributor who wants to keep their own code proprietary must
+purchase an appropriate Cygwin licence.
+
+MinGW has no such restrictions. The MinGW compiler generates a library or
+executable that can run standalone on Windows without any third party dll or
+licensing issues.
+
+But there is more complication:
+
+If a Cygwin user uses the -mno-cygwin Cygwin gcc flag, what that really does is
+to tell Cygwin's gcc to use the MinGW gcc. Cygwin's gcc is only acting as a
+front end to MinGW's gcc (if you install Cygwin's gcc, you get both Cygwin's
+gcc and MinGW's gcc). So, a user can:
+
+. Build native binaries by using MinGW or by getting Cygwin and using
+  -mno-cygwin.
+
+. Build binaries that depend on cygwin1.dll by using Cygwin with the normal
+  compiler flags.
+
+The test files that are supplied with PCRE are in UNIX format, with LF
+characters as line terminators. Unless your PCRE library uses a default newline
+option that includes LF as a valid newline, it may be necessary to change the
+line terminators in the test files to get some of the tests to work.
+
+
+BUILDING PCRE ON WINDOWS WITH CMAKE
+
+CMake is an alternative configuration facility that can be used instead of
+"configure". CMake creates project files (make files, solution files, etc.)
+tailored to numerous development environments, including Visual Studio,
+Borland, Msys, MinGW, NMake, and Unix. If possible, use short paths with no
+spaces in the names for your CMake installation and your PCRE source and build
+directories.
+
+The following instructions were contributed by a PCRE user. If they are not
+followed exactly, errors may occur. In the event that errors do occur, it is
+recommended that you delete the CMake cache before attempting to repeat the
+CMake build process. In the CMake GUI, the cache can be deleted by selecting
+"File > Delete Cache".
+
+1.  Install the latest CMake version available from http://www.cmake.org/, and
+    ensure that cmake\bin is on your path.
+
+2.  Unzip (retaining folder structure) the PCRE source tree into a source
+    directory such as C:\pcre. You should ensure your local date and time
+    is not earlier than the file dates in your source dir if the release is
+    very new.
+
+3.  Create a new, empty build directory, preferably a subdirectory of the
+    source dir. For example, C:\pcre\pcre-xx\build.
+
+4.  Run cmake-gui from the Shell envirornment of your build tool, for example,
+    Msys for Msys/MinGW or Visual Studio Command Prompt for VC/VC++. Do not try
+    to start Cmake from the Windows Start menu, as this can lead to errors.
+
+5.  Enter C:\pcre\pcre-xx and C:\pcre\pcre-xx\build for the source and build
+    directories, respectively.
+
+6.  Hit the "Configure" button.
+
+7.  Select the particular IDE / build tool that you are using (Visual
+    Studio, MSYS makefiles, MinGW makefiles, etc.)
+
+8.  The GUI will then list several configuration options. This is where
+    you can enable UTF-8 support or other PCRE optional features.
+
+9.  Hit "Configure" again. The adjacent "Generate" button should now be
+    active.
+
+10. Hit "Generate".
+
+11. The build directory should now contain a usable build system, be it a
+    solution file for Visual Studio, makefiles for MinGW, etc. Exit from
+    cmake-gui and use the generated build system with your compiler or IDE.
+    E.g., for MinGW you can run "make", or for Visual Studio, open the PCRE
+    solution, select the desired configuration (Debug, or Release, etc.) and
+    build the ALL_BUILD project.
+
+12. If during configuration with cmake-gui you've elected to build the test
+    programs, you can execute them by building the test project. E.g., for
+    MinGW: "make test"; for Visual Studio build the RUN_TESTS project. The
+    most recent build configuration is targeted by the tests. A summary of
+    test results is presented. Complete test output is subsequently
+    available for review in Testing\Temporary under your build dir.
+
+
+USE OF RELATIVE PATHS WITH CMAKE ON WINDOWS
+
+A PCRE user comments as follows: I thought that others may want to know the
+current state of CMAKE_USE_RELATIVE_PATHS support on Windows. Here it is:
+
+-- AdditionalIncludeDirectories is only partially modified (only the
+   first path - see below)
+-- Only some of the contained file paths are modified - shown below for
+   pcre.vcproj
+-- It properly modifies
+
+I am sure CMake people can fix that if they want to. Until then one will
+need to replace existing absolute paths in project files with relative
+paths manually (e.g. from VS) - relative to project file location. I did
+just that before being told to try CMAKE_USE_RELATIVE_PATHS. Not a big
+deal.
+
+AdditionalIncludeDirectories="E:\builds\pcre\build;E:\builds\pcre\pcre-7.5;"
+AdditionalIncludeDirectories=".;E:\builds\pcre\pcre-7.5;"
+
+RelativePath="pcre.h"
+RelativePath="pcre_chartables.c"
+RelativePath="pcre_chartables.c.rule"
+
+
+TESTING WITH RUNTEST.BAT
+
+If configured with CMake, building the test project ("make test" or building
+ALL_TESTS in Visual Studio) creates (and runs) pcre_test.bat (and depending
+on your configuration options, possibly other test programs) in the build
+directory. Pcre_test.bat runs RunTest.Bat with correct source and exe paths.
+
+For manual testing with RunTest.bat, provided the build dir is a subdirectory
+of the source directory: Open command shell window. Chdir to the location
+of your pcretest.exe and pcregrep.exe programs. Call RunTest.bat with
+"..\RunTest.Bat" or "..\..\RunTest.bat" as appropriate.
+
+To run only a particular test with RunTest.Bat provide a test number argument.
+
+Otherwise:
+
+1. Copy RunTest.bat into the directory where pcretest.exe and pcregrep.exe
+   have been created.
+
+2. Edit RunTest.bat to indentify the full or relative location of
+   the pcre source (wherein which the testdata folder resides), e.g.:
+
+   set srcdir=C:\pcre\pcre-8.20
+
+3. In a Windows command environment, chdir to the location of your bat and
+   exe programs.
+
+4. Run RunTest.bat. Test outputs will automatically be compared to expected
+   results, and discrepancies will be identified in the console output.
+
+To independently test the just-in-time compiler, run pcre_jit_test.exe.
+To test pcrecpp, run pcrecpp_unittest.exe, pcre_stringpiece_unittest.exe and
+pcre_scanner_unittest.exe.
+
+
+BUILDING UNDER WINDOWS CE WITH VISUAL STUDIO 200x
+
+Vincent Richomme sent a zip archive of files to help with this process. They
+can be found in the file "pcre-vsbuild.zip" in the Contrib directory of the FTP
+site.
+
+
+BUILDING UNDER WINDOWS WITH BCC5.5
+
+Michael Roy sent these comments about building PCRE under Windows with BCC5.5:
+
+Some of the core BCC libraries have a version of PCRE from 1998 built in, which
+can lead to pcre_exec() giving an erroneous PCRE_ERROR_NULL from a version
+mismatch. I'm including an easy workaround below, if you'd like to include it
+in the non-unix instructions:
+
+When linking a project with BCC5.5, pcre.lib must be included before any of the
+libraries cw32.lib, cw32i.lib, cw32mt.lib, and cw32mti.lib on the command line.
+
+
+BUILDING USING BORLAND C++ BUILDER 2007 (CB2007) AND HIGHER
+
+A PCRE user sent these comments about this environment (see also the comment
+from another user that follows them):
+
+The XE versions of C++ Builder come with a RegularExpressionsCore class which
+contain a version of TPerlRegEx. However, direct use of the C PCRE library may
+be desirable.
+
+The default makevp.bat, however, supplied with PCRE builds a version of PCRE
+that is not usable with any version of C++ Builder because the compiler ships
+with an embedded version of PCRE, version 2.01 from 1998! [See also the note
+about BCC5.5 above.] If you want to use PCRE you'll need to rename the
+functions (pcre_compile to pcre_compile_bcc, etc) or do as I have done and just
+use the 16 bit versions. I'm using std::wstring everywhere anyway. Since the
+embedded version of PCRE does not have the 16 bit function names, there is no
+conflict.
+
+Building PCRE using a C++ Builder static library project file (recommended):
+
+1. Rename or remove pcre.h, pcreposi.h, and pcreposix.h from your C++ Builder
+original include path.
+
+2. Download PCRE from pcre.org and extract to a directory.
+
+3. Rename pcre_chartables.c.dist to pcre_chartables.c, pcre.h.generic to
+pcre.h, and config.h.generic to config.h.
+
+4. Edit pcre.h and pcre_config.c so that they include config.h.
+
+5. Edit config.h like so:
+
+Comment out the following lines:
+#define PACKAGE "pcre"
+#define PACKAGE_BUGREPORT ""
+#define PACKAGE_NAME "PCRE"
+#define PACKAGE_STRING "PCRE 8.32"
+#define PACKAGE_TARNAME "pcre"
+#define PACKAGE_URL ""
+#define PACKAGE_VERSION "8.32"
+
+Add the following lines:
+#ifndef SUPPORT_UTF
+#define SUPPORT_UTF 100 // any value is fine
+#endif
+
+#ifndef SUPPORT_UCP
+#define SUPPORT_UCP 101 // any value is fine
+#endif
+
+#ifndef SUPPORT_UCP
+#define SUPPORT_PCRE16 102 // any value is fine
+#endif
+
+#ifndef SUPPORT_UTF8
+#define SUPPORT_UTF8 103 // any value is fine
+#endif
+
+6. Build a C++ Builder project using the IDE. Go to File / New / Other and
+choose Static Library. You can name it pcre.cbproj or whatever. Now set your
+paths by going to Project / Options. Set the Include path. Do this from the
+"Base" option to apply to both Release and Debug builds. Now add the following
+files to the project:
+
+pcre.h
+pcre16_byte_order.c
+pcre16_chartables.c
+pcre16_compile.c
+pcre16_config.c
+pcre16_dfa_exec.c
+pcre16_exec.c
+pcre16_fullinfo.c
+pcre16_get.c
+pcre16_globals.c
+pcre16_maketables.c
+pcre16_newline.c
+pcre16_ord2utf16.c
+pcre16_printint.c
+pcre16_refcount.c
+pcre16_string_utils.c
+pcre16_study.c
+pcre16_tables.c
+pcre16_ucd.c
+pcre16_utf16_utils.c
+pcre16_valid_utf16.c
+pcre16_version.c
+pcre16_xclass.c
+
+//Optional
+pcre_version.c
+
+7. After compiling the .lib file, copy the .lib and header files to a project
+you want to use PCRE with. Enjoy.
+
+Optional ... Building PCRE using the makevp.bat file:
+
+1. Edit makevp_c.txt and makevp_l.txt and change all the names to the 16 bit
+versions.
+
+2. Edit makevp.bat and set the path to C++ Builder. Run makevp.bat.
+
+Another PCRE user added this comment:
+
+Another approach I successfully used for some years with BCB 5 and 6 was to
+make sure that include and library paths of PCRE are configured before the
+default paths of the IDE in the dialogs where one can manage those paths.
+Afterwards one can open the project files using a text editor and manually add
+the self created library for pcre itself, pcrecpp doesn't ship with the IDE, in
+the library nodes where the IDE manages its own libraries to link against in
+front of the IDE-own libraries. This way one can use the default PCRE function
+names without getting access violations on runtime.
+
+  <ALLLIB value="libpcre.lib $(LIBFILES) $(LIBRARIES) import32.lib cp32mt.lib"/>
+
+
+BUILDING PCRE ON OPENVMS
+
+Stephen Hoffman sent the following, in December 2012:
+
+"Here <http://labs.hoffmanlabs.com/node/1847> is a very short write-up on the
+OpenVMS port and here
+
+<http://labs.hoffmanlabs.com/labsnotes/pcre-vms-8_32.zip>
+
+is a zip with the OpenVMS files, and with one modified testing-related PCRE
+file." This is a port of PCRE 8.32.
+
+Earlier, Dan Mooney sent the following comments about building PCRE on OpenVMS.
+They relate to an older version of PCRE that used fewer source files, so the
+exact commands will need changing. See the current list of source files above.
+
+"It was quite easy to compile and link the library. I don't have a formal
+make file but the attached file [reproduced below] contains the OpenVMS DCL
+commands I used to build the library. I had to add #define
+POSIX_MALLOC_THRESHOLD 10 to pcre.h since it was not defined anywhere.
+
+The library was built on:
+O/S: HP OpenVMS v7.3-1
+Compiler: Compaq C v6.5-001-48BCD
+Linker: vA13-01
+
+The test results did not match 100% due to the issues you mention in your
+documentation regarding isprint(), iscntrl(), isgraph() and ispunct(). I
+modified some of the character tables temporarily and was able to get the
+results to match. Tests using the fr locale did not match since I don't have
+that locale loaded. The study size was always reported to be 3 less than the
+value in the standard test output files."
+
+=========================
+$! This DCL procedure builds PCRE on OpenVMS
+$!
+$! I followed the instructions in the non-unix-use file in the distribution.
+$!
+$ COMPILE == "CC/LIST/NOMEMBER_ALIGNMENT/PREFIX_LIBRARY_ENTRIES=ALL_ENTRIES
+$ COMPILE DFTABLES.C
+$ LINK/EXE=DFTABLES.EXE DFTABLES.OBJ
+$ RUN DFTABLES.EXE/OUTPUT=CHARTABLES.C
+$ COMPILE MAKETABLES.C
+$ COMPILE GET.C
+$ COMPILE STUDY.C
+$! I had to set POSIX_MALLOC_THRESHOLD to 10 in PCRE.H since the symbol
+$! did not seem to be defined anywhere.
+$! I edited pcre.h and added #DEFINE SUPPORT_UTF8 to enable UTF8 support.
+$ COMPILE PCRE.C
+$ LIB/CREATE PCRE MAKETABLES.OBJ, GET.OBJ, STUDY.OBJ, PCRE.OBJ
+$! I had to set POSIX_MALLOC_THRESHOLD to 10 in PCRE.H since the symbol
+$! did not seem to be defined anywhere.
+$ COMPILE PCREPOSIX.C
+$ LIB/CREATE PCREPOSIX PCREPOSIX.OBJ
+$ COMPILE PCRETEST.C
+$ LINK/EXE=PCRETEST.EXE PCRETEST.OBJ, PCRE/LIB, PCREPOSIX/LIB
+$! C programs that want access to command line arguments must be
+$! defined as a symbol
+$ PCRETEST :== "$ SYS$ROADSUSERS:[DMOONEY.REGEXP]PCRETEST.EXE"
+$! Arguments must be enclosed in quotes.
+$ PCRETEST "-C"
+$! Test results:
+$!
+$!   The test results did not match 100%. The functions isprint(), iscntrl(),
+$!   isgraph() and ispunct() on OpenVMS must not produce the same results
+$!   as the system that built the test output files provided with the
+$!   distribution.
+$!
+$!   The study size did not match and was always 3 less on OpenVMS.
+$!
+$!   Locale could not be set to fr
+$!
+=========================
+
+
+BUILDING PCRE ON STRATUS OPENVOS
+
+These notes on the port of PCRE to VOS (lightly edited) were supplied by
+Ashutosh Warikoo, whose email address has the local part awarikoo and the
+domain nse.co.in. The port was for version 7.9 in August 2009.
+
+1.   Building PCRE
+
+I built pcre on OpenVOS Release 17.0.1at using GNU Tools 3.4a without any
+problems. I used the following packages to build PCRE:
+
+  ftp://ftp.stratus.com/pub/vos/posix/ga/posix.save.evf.gz
+
+Please read and follow the instructions that come with these packages. To start
+the build of pcre, from the root of the package type:
+
+  ./build.sh
+
+2. Installing PCRE
+
+Once you have successfully built PCRE, login to the SysAdmin group, switch to
+the root user, and type
+
+  [ !create_dir (master_disk)>usr   --if needed ]
+  [ !create_dir (master_disk)>usr>local   --if needed ]
+    !gmake install
+
+This installs PCRE and its man pages into /usr/local. You can add
+(master_disk)>usr>local>bin to your command search paths, or if you are in
+BASH, add /usr/local/bin to the PATH environment variable.
+
+4. Restrictions
+
+This port requires readline library optionally. However during the build I
+faced some yet unexplored errors while linking with readline. As it was an
+optional component I chose to disable it.
+
+5. Known Problems
+
+I ran the test suite, but you will have to be your own judge of whether this
+command, and this port, suits your purposes. If you find any problems that
+appear to be related to the port itself, please let me know. Please see the
+build.log file in the root of the package also.
+
+
+BUILDING PCRE ON NATIVE Z/OS AND Z/VM
+
+z/OS and z/VM are operating systems for mainframe computers, produced by IBM.
+The character code used is EBCDIC, not ASCII or Unicode. In z/OS, UNIX APIs and
+applications can be supported through UNIX System Services, and in such an
+environment PCRE can be built in the same way as in other systems. However, in
+native z/OS (without UNIX System Services) and in z/VM, special ports are
+required. For details, please see this web site:
+
+  http://www.zaconsultants.net
+
+There is also a mirror here:
+
+  http://www.vsoft-software.com/downloads.html
+
+==========================
+Last Updated: 14 May 2013
diff --git a/libs/Pcre16/docs/NON-UNIX-USE b/libs/Pcre16/docs/NON-UNIX-USE
new file mode 100644
index 0000000000..a25546b6ff
--- /dev/null
+++ b/libs/Pcre16/docs/NON-UNIX-USE
@@ -0,0 +1,7 @@
+Compiling PCRE on non-Unix systems
+----------------------------------
+
+This has been renamed to better reflect its contents. Please see the file
+NON-AUTOTOOLS-BUILD for details of how to build PCRE without using autotools.
+
+####
diff --git a/libs/Pcre16/docs/README b/libs/Pcre16/docs/README
new file mode 100644
index 0000000000..88f2dfd4ef
--- /dev/null
+++ b/libs/Pcre16/docs/README
@@ -0,0 +1,991 @@
+README file for PCRE (Perl-compatible regular expression library)
+-----------------------------------------------------------------
+
+The latest release of PCRE is always available in three alternative formats
+from:
+
+  ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre/pcre-xxx.tar.gz
+  ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre/pcre-xxx.tar.bz2
+  ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre/pcre-xxx.zip
+
+There is a mailing list for discussion about the development of PCRE at
+pcre-dev@exim.org. You can access the archives and subscribe or manage your
+subscription here:
+
+   https://lists.exim.org/mailman/listinfo/pcre-dev
+
+Please read the NEWS file if you are upgrading from a previous release.
+The contents of this README file are:
+
+  The PCRE APIs
+  Documentation for PCRE
+  Contributions by users of PCRE
+  Building PCRE on non-Unix-like systems
+  Building PCRE without using autotools
+  Building PCRE using autotools
+  Retrieving configuration information
+  Shared libraries
+  Cross-compiling using autotools
+  Using HP's ANSI C++ compiler (aCC)
+  Compiling in Tru64 using native compilers
+  Using Sun's compilers for Solaris
+  Using PCRE from MySQL
+  Making new tarballs
+  Testing PCRE
+  Character tables
+  File manifest
+
+
+The PCRE APIs
+-------------
+
+PCRE is written in C, and it has its own API. There are three sets of
+functions, one for the 8-bit library, which processes strings of bytes, one for
+the 16-bit library, which processes strings of 16-bit values, and one for the
+32-bit library, which processes strings of 32-bit values. The distribution also
+includes a set of C++ wrapper functions (see the pcrecpp man page for details),
+courtesy of Google Inc., which can be used to call the 8-bit PCRE library from
+C++.
+
+In addition, there is a set of C wrapper functions (again, just for the 8-bit
+library) that are based on the POSIX regular expression API (see the pcreposix
+man page). These end up in the library called libpcreposix. Note that this just
+provides a POSIX calling interface to PCRE; the regular expressions themselves
+still follow Perl syntax and semantics. The POSIX API is restricted, and does
+not give full access to all of PCRE's facilities.
+
+The header file for the POSIX-style functions is called pcreposix.h. The
+official POSIX name is regex.h, but I did not want to risk possible problems
+with existing files of that name by distributing it that way. To use PCRE with
+an existing program that uses the POSIX API, pcreposix.h will have to be
+renamed or pointed at by a link.
+
+If you are using the POSIX interface to PCRE and there is already a POSIX regex
+library installed on your system, as well as worrying about the regex.h header
+file (as mentioned above), you must also take care when linking programs to
+ensure that they link with PCRE's libpcreposix library. Otherwise they may pick
+up the POSIX functions of the same name from the other library.
+
+One way of avoiding this confusion is to compile PCRE with the addition of
+-Dregcomp=PCREregcomp (and similarly for the other POSIX functions) to the
+compiler flags (CFLAGS if you are using "configure" -- see below). This has the
+effect of renaming the functions so that the names no longer clash. Of course,
+you have to do the same thing for your applications, or write them using the
+new names.
+
+
+Documentation for PCRE
+----------------------
+
+If you install PCRE in the normal way on a Unix-like system, you will end up
+with a set of man pages whose names all start with "pcre". The one that is just
+called "pcre" lists all the others. In addition to these man pages, the PCRE
+documentation is supplied in two other forms:
+
+  1. There are files called doc/pcre.txt, doc/pcregrep.txt, and
+     doc/pcretest.txt in the source distribution. The first of these is a
+     concatenation of the text forms of all the section 3 man pages except
+     the listing of pcredemo.c and those that summarize individual functions.
+     The other two are the text forms of the section 1 man pages for the
+     pcregrep and pcretest commands. These text forms are provided for ease of
+     scanning with text editors or similar tools. They are installed in
+     <prefix>/share/doc/pcre, where <prefix> is the installation prefix
+     (defaulting to /usr/local).
+
+  2. A set of files containing all the documentation in HTML form, hyperlinked
+     in various ways, and rooted in a file called index.html, is distributed in
+     doc/html and installed in <prefix>/share/doc/pcre/html.
+
+Users of PCRE have contributed files containing the documentation for various
+releases in CHM format. These can be found in the Contrib directory of the FTP
+site (see next section).
+
+
+Contributions by users of PCRE
+------------------------------
+
+You can find contributions from PCRE users in the directory
+
+  ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre/Contrib
+
+There is a README file giving brief descriptions of what they are. Some are
+complete in themselves; others are pointers to URLs containing relevant files.
+Some of this material is likely to be well out-of-date. Several of the earlier
+contributions provided support for compiling PCRE on various flavours of
+Windows (I myself do not use Windows). Nowadays there is more Windows support
+in the standard distribution, so these contibutions have been archived.
+
+A PCRE user maintains downloadable Windows binaries of the pcregrep and
+pcretest programs here:
+
+  http://www.rexegg.com/pcregrep-pcretest.html
+
+
+Building PCRE on non-Unix-like systems
+--------------------------------------
+
+For a non-Unix-like system, please read the comments in the file
+NON-AUTOTOOLS-BUILD, though if your system supports the use of "configure" and
+"make" you may be able to build PCRE using autotools in the same way as for
+many Unix-like systems.
+
+PCRE can also be configured using the GUI facility provided by CMake's
+cmake-gui command. This creates Makefiles, solution files, etc. The file
+NON-AUTOTOOLS-BUILD has information about CMake.
+
+PCRE has been compiled on many different operating systems. It should be
+straightforward to build PCRE on any system that has a Standard C compiler and
+library, because it uses only Standard C functions.
+
+
+Building PCRE without using autotools
+-------------------------------------
+
+The use of autotools (in particular, libtool) is problematic in some
+environments, even some that are Unix or Unix-like. See the NON-AUTOTOOLS-BUILD
+file for ways of building PCRE without using autotools.
+
+
+Building PCRE using autotools
+-----------------------------
+
+If you are using HP's ANSI C++ compiler (aCC), please see the special note
+in the section entitled "Using HP's ANSI C++ compiler (aCC)" below.
+
+The following instructions assume the use of the widely used "configure; make;
+make install" (autotools) process.
+
+To build PCRE on system that supports autotools, first run the "configure"
+command from the PCRE distribution directory, with your current directory set
+to the directory where you want the files to be created. This command is a
+standard GNU "autoconf" configuration script, for which generic instructions
+are supplied in the file INSTALL.
+
+Most commonly, people build PCRE within its own distribution directory, and in
+this case, on many systems, just running "./configure" is sufficient. However,
+the usual methods of changing standard defaults are available. For example:
+
+CFLAGS='-O2 -Wall' ./configure --prefix=/opt/local
+
+This command specifies that the C compiler should be run with the flags '-O2
+-Wall' instead of the default, and that "make install" should install PCRE
+under /opt/local instead of the default /usr/local.
+
+If you want to build in a different directory, just run "configure" with that
+directory as current. For example, suppose you have unpacked the PCRE source
+into /source/pcre/pcre-xxx, but you want to build it in /build/pcre/pcre-xxx:
+
+cd /build/pcre/pcre-xxx
+/source/pcre/pcre-xxx/configure
+
+PCRE is written in C and is normally compiled as a C library. However, it is
+possible to build it as a C++ library, though the provided building apparatus
+does not have any features to support this.
+
+There are some optional features that can be included or omitted from the PCRE
+library. They are also documented in the pcrebuild man page.
+
+. By default, both shared and static libraries are built. You can change this
+  by adding one of these options to the "configure" command:
+
+  --disable-shared
+  --disable-static
+
+  (See also "Shared libraries on Unix-like systems" below.)
+
+. By default, only the 8-bit library is built. If you add --enable-pcre16 to
+  the "configure" command, the 16-bit library is also built. If you add
+  --enable-pcre32 to the "configure" command, the 32-bit library is also built.
+  If you want only the 16-bit or 32-bit library, use --disable-pcre8 to disable
+  building the 8-bit library.
+
+. If you are building the 8-bit library and want to suppress the building of
+  the C++ wrapper library, you can add --disable-cpp to the "configure"
+  command. Otherwise, when "configure" is run without --disable-pcre8, it will
+  try to find a C++ compiler and C++ header files, and if it succeeds, it will
+  try to build the C++ wrapper.
+
+. If you want to include support for just-in-time compiling, which can give
+  large performance improvements on certain platforms, add --enable-jit to the
+  "configure" command. This support is available only for certain hardware
+  architectures. If you try to enable it on an unsupported architecture, there
+  will be a compile time error.
+
+. When JIT support is enabled, pcregrep automatically makes use of it, unless
+  you add --disable-pcregrep-jit to the "configure" command.
+
+. If you want to make use of the support for UTF-8 Unicode character strings in
+  the 8-bit library, or UTF-16 Unicode character strings in the 16-bit library,
+  or UTF-32 Unicode character strings in the 32-bit library, you must add
+  --enable-utf to the "configure" command. Without it, the code for handling
+  UTF-8, UTF-16 and UTF-8 is not included in the relevant library. Even
+  when --enable-utf is included, the use of a UTF encoding still has to be
+  enabled by an option at run time. When PCRE is compiled with this option, its
+  input can only either be ASCII or UTF-8/16/32, even when running on EBCDIC
+  platforms. It is not possible to use both --enable-utf and --enable-ebcdic at
+  the same time.
+
+. There are no separate options for enabling UTF-8, UTF-16 and UTF-32
+  independently because that would allow ridiculous settings such as requesting
+  UTF-16 support while building only the 8-bit library. However, the option
+  --enable-utf8 is retained for backwards compatibility with earlier releases
+  that did not support 16-bit or 32-bit character strings. It is synonymous with
+  --enable-utf. It is not possible to configure one library with UTF support
+  and the other without in the same configuration.
+
+. If, in addition to support for UTF-8/16/32 character strings, you want to
+  include support for the \P, \p, and \X sequences that recognize Unicode
+  character properties, you must add --enable-unicode-properties to the
+  "configure" command. This adds about 30K to the size of the library (in the
+  form of a property table); only the basic two-letter properties such as Lu
+  are supported.
+
+. You can build PCRE to recognize either CR or LF or the sequence CRLF or any
+  of the preceding, or any of the Unicode newline sequences as indicating the
+  end of a line. Whatever you specify at build time is the default; the caller
+  of PCRE can change the selection at run time. The default newline indicator
+  is a single LF character (the Unix standard). You can specify the default
+  newline indicator by adding --enable-newline-is-cr or --enable-newline-is-lf
+  or --enable-newline-is-crlf or --enable-newline-is-anycrlf or
+  --enable-newline-is-any to the "configure" command, respectively.
+
+  If you specify --enable-newline-is-cr or --enable-newline-is-crlf, some of
+  the standard tests will fail, because the lines in the test files end with
+  LF. Even if the files are edited to change the line endings, there are likely
+  to be some failures. With --enable-newline-is-anycrlf or
+  --enable-newline-is-any, many tests should succeed, but there may be some
+  failures.
+
+. By default, the sequence \R in a pattern matches any Unicode line ending
+  sequence. This is independent of the option specifying what PCRE considers to
+  be the end of a line (see above). However, the caller of PCRE can restrict \R
+  to match only CR, LF, or CRLF. You can make this the default by adding
+  --enable-bsr-anycrlf to the "configure" command (bsr = "backslash R").
+
+. When called via the POSIX interface, PCRE uses malloc() to get additional
+  storage for processing capturing parentheses if there are more than 10 of
+  them in a pattern. You can increase this threshold by setting, for example,
+
+  --with-posix-malloc-threshold=20
+
+  on the "configure" command.
+
+. PCRE has a counter that limits the depth of nesting of parentheses in a
+  pattern. This limits the amount of system stack that a pattern uses when it
+  is compiled. The default is 250, but you can change it by setting, for
+  example,
+
+  --with-parens-nest-limit=500
+
+. PCRE has a counter that can be set to limit the amount of resources it uses
+  when matching a pattern. If the limit is exceeded during a match, the match
+  fails. The default is ten million. You can change the default by setting, for
+  example,
+
+  --with-match-limit=500000
+
+  on the "configure" command. This is just the default; individual calls to
+  pcre_exec() can supply their own value. There is more discussion on the
+  pcreapi man page.
+
+. There is a separate counter that limits the depth of recursive function calls
+  during a matching process. This also has a default of ten million, which is
+  essentially "unlimited". You can change the default by setting, for example,
+
+  --with-match-limit-recursion=500000
+
+  Recursive function calls use up the runtime stack; running out of stack can
+  cause programs to crash in strange ways. There is a discussion about stack
+  sizes in the pcrestack man page.
+
+. The default maximum compiled pattern size is around 64K. You can increase
+  this by adding --with-link-size=3 to the "configure" command. In the 8-bit
+  library, PCRE then uses three bytes instead of two for offsets to different
+  parts of the compiled pattern. In the 16-bit library, --with-link-size=3 is
+  the same as --with-link-size=4, which (in both libraries) uses four-byte
+  offsets. Increasing the internal link size reduces performance. In the 32-bit
+  library, the only supported link size is 4.
+
+. You can build PCRE so that its internal match() function that is called from
+  pcre_exec() does not call itself recursively. Instead, it uses memory blocks
+  obtained from the heap via the special functions pcre_stack_malloc() and
+  pcre_stack_free() to save data that would otherwise be saved on the stack. To
+  build PCRE like this, use
+
+  --disable-stack-for-recursion
+
+  on the "configure" command. PCRE runs more slowly in this mode, but it may be
+  necessary in environments with limited stack sizes. This applies only to the
+  normal execution of the pcre_exec() function; if JIT support is being
+  successfully used, it is not relevant. Equally, it does not apply to
+  pcre_dfa_exec(), which does not use deeply nested recursion. There is a
+  discussion about stack sizes in the pcrestack man page.
+
+. For speed, PCRE uses four tables for manipulating and identifying characters
+  whose code point values are less than 256. By default, it uses a set of
+  tables for ASCII encoding that is part of the distribution. If you specify
+
+  --enable-rebuild-chartables
+
+  a program called dftables is compiled and run in the default C locale when
+  you obey "make". It builds a source file called pcre_chartables.c. If you do
+  not specify this option, pcre_chartables.c is created as a copy of
+  pcre_chartables.c.dist. See "Character tables" below for further information.
+
+. It is possible to compile PCRE for use on systems that use EBCDIC as their
+  character code (as opposed to ASCII/Unicode) by specifying
+
+  --enable-ebcdic
+
+  This automatically implies --enable-rebuild-chartables (see above). However,
+  when PCRE is built this way, it always operates in EBCDIC. It cannot support
+  both EBCDIC and UTF-8/16/32. There is a second option, --enable-ebcdic-nl25,
+  which specifies that the code value for the EBCDIC NL character is 0x25
+  instead of the default 0x15.
+
+. In environments where valgrind is installed, if you specify
+
+  --enable-valgrind
+
+  PCRE will use valgrind annotations to mark certain memory regions as
+  unaddressable. This allows it to detect invalid memory accesses, and is
+  mostly useful for debugging PCRE itself.
+
+. In environments where the gcc compiler is used and lcov version 1.6 or above
+  is installed, if you specify
+
+  --enable-coverage
+
+  the build process implements a code coverage report for the test suite. The
+  report is generated by running "make coverage". If ccache is installed on
+  your system, it must be disabled when building PCRE for coverage reporting.
+  You can do this by setting the environment variable CCACHE_DISABLE=1 before
+  running "make" to build PCRE. There is more information about coverage
+  reporting in the "pcrebuild" documentation.
+
+. The pcregrep program currently supports only 8-bit data files, and so
+  requires the 8-bit PCRE library. It is possible to compile pcregrep to use
+  libz and/or libbz2, in order to read .gz and .bz2 files (respectively), by
+  specifying one or both of
+
+  --enable-pcregrep-libz
+  --enable-pcregrep-libbz2
+
+  Of course, the relevant libraries must be installed on your system.
+
+. The default size (in bytes) of the internal buffer used by pcregrep can be
+  set by, for example:
+
+  --with-pcregrep-bufsize=51200
+
+  The value must be a plain integer. The default is 20480.
+
+. It is possible to compile pcretest so that it links with the libreadline
+  or libedit libraries, by specifying, respectively,
+
+  --enable-pcretest-libreadline or --enable-pcretest-libedit
+
+  If this is done, when pcretest's input is from a terminal, it reads it using
+  the readline() function. This provides line-editing and history facilities.
+  Note that libreadline is GPL-licenced, so if you distribute a binary of
+  pcretest linked in this way, there may be licensing issues. These can be
+  avoided by linking with libedit (which has a BSD licence) instead.
+
+  Enabling libreadline causes the -lreadline option to be added to the pcretest
+  build. In many operating environments with a sytem-installed readline
+  library this is sufficient. However, in some environments (e.g. if an
+  unmodified distribution version of readline is in use), it may be necessary
+  to specify something like LIBS="-lncurses" as well. This is because, to quote
+  the readline INSTALL, "Readline uses the termcap functions, but does not link
+  with the termcap or curses library itself, allowing applications which link
+  with readline the to choose an appropriate library." If you get error
+  messages about missing functions tgetstr, tgetent, tputs, tgetflag, or tgoto,
+  this is the problem, and linking with the ncurses library should fix it.
+
+The "configure" script builds the following files for the basic C library:
+
+. Makefile             the makefile that builds the library
+. config.h             build-time configuration options for the library
+. pcre.h               the public PCRE header file
+. pcre-config          script that shows the building settings such as CFLAGS
+                         that were set for "configure"
+. libpcre.pc         ) data for the pkg-config command
+. libpcre16.pc       )
+. libpcre32.pc       )
+. libpcreposix.pc    )
+. libtool              script that builds shared and/or static libraries
+
+Versions of config.h and pcre.h are distributed in the PCRE tarballs under the
+names config.h.generic and pcre.h.generic. These are provided for those who
+have to built PCRE without using "configure" or CMake. If you use "configure"
+or CMake, the .generic versions are not used.
+
+When building the 8-bit library, if a C++ compiler is found, the following
+files are also built:
+
+. libpcrecpp.pc        data for the pkg-config command
+. pcrecpparg.h         header file for calling PCRE via the C++ wrapper
+. pcre_stringpiece.h   header for the C++ "stringpiece" functions
+
+The "configure" script also creates config.status, which is an executable
+script that can be run to recreate the configuration, and config.log, which
+contains compiler output from tests that "configure" runs.
+
+Once "configure" has run, you can run "make". This builds the the libraries
+libpcre, libpcre16 and/or libpcre32, and a test program called pcretest. If you
+enabled JIT support with --enable-jit, a test program called pcre_jit_test is
+built as well.
+
+If the 8-bit library is built, libpcreposix and the pcregrep command are also
+built, and if a C++ compiler was found on your system, and you did not disable
+it with --disable-cpp, "make" builds the C++ wrapper library, which is called
+libpcrecpp, as well as some test programs called pcrecpp_unittest,
+pcre_scanner_unittest, and pcre_stringpiece_unittest.
+
+The command "make check" runs all the appropriate tests. Details of the PCRE
+tests are given below in a separate section of this document.
+
+You can use "make install" to install PCRE into live directories on your
+system. The following are installed (file names are all relative to the
+<prefix> that is set when "configure" is run):
+
+  Commands (bin):
+    pcretest
+    pcregrep (if 8-bit support is enabled)
+    pcre-config
+
+  Libraries (lib):
+    libpcre16     (if 16-bit support is enabled)
+    libpcre32     (if 32-bit support is enabled)
+    libpcre       (if 8-bit support is enabled)
+    libpcreposix  (if 8-bit support is enabled)
+    libpcrecpp    (if 8-bit and C++ support is enabled)
+
+  Configuration information (lib/pkgconfig):
+    libpcre16.pc
+    libpcre32.pc
+    libpcre.pc
+    libpcreposix.pc
+    libpcrecpp.pc (if C++ support is enabled)
+
+  Header files (include):
+    pcre.h
+    pcreposix.h
+    pcre_scanner.h      )
+    pcre_stringpiece.h  ) if C++ support is enabled
+    pcrecpp.h           )
+    pcrecpparg.h        )
+
+  Man pages (share/man/man{1,3}):
+    pcregrep.1
+    pcretest.1
+    pcre-config.1
+    pcre.3
+    pcre*.3 (lots more pages, all starting "pcre")
+
+  HTML documentation (share/doc/pcre/html):
+    index.html
+    *.html (lots more pages, hyperlinked from index.html)
+
+  Text file documentation (share/doc/pcre):
+    AUTHORS
+    COPYING
+    ChangeLog
+    LICENCE
+    NEWS
+    README
+    pcre.txt         (a concatenation of the man(3) pages)
+    pcretest.txt     the pcretest man page
+    pcregrep.txt     the pcregrep man page
+    pcre-config.txt  the pcre-config man page
+
+If you want to remove PCRE from your system, you can run "make uninstall".
+This removes all the files that "make install" installed. However, it does not
+remove any directories, because these are often shared with other programs.
+
+
+Retrieving configuration information
+------------------------------------
+
+Running "make install" installs the command pcre-config, which can be used to
+recall information about the PCRE configuration and installation. For example:
+
+  pcre-config --version
+
+prints the version number, and
+
+  pcre-config --libs
+
+outputs information about where the library is installed. This command can be
+included in makefiles for programs that use PCRE, saving the programmer from
+having to remember too many details.
+
+The pkg-config command is another system for saving and retrieving information
+about installed libraries. Instead of separate commands for each library, a
+single command is used. For example:
+
+  pkg-config --cflags pcre
+
+The data is held in *.pc files that are installed in a directory called
+<prefix>/lib/pkgconfig.
+
+
+Shared libraries
+----------------
+
+The default distribution builds PCRE as shared libraries and static libraries,
+as long as the operating system supports shared libraries. Shared library
+support relies on the "libtool" script which is built as part of the
+"configure" process.
+
+The libtool script is used to compile and link both shared and static
+libraries. They are placed in a subdirectory called .libs when they are newly
+built. The programs pcretest and pcregrep are built to use these uninstalled
+libraries (by means of wrapper scripts in the case of shared libraries). When
+you use "make install" to install shared libraries, pcregrep and pcretest are
+automatically re-built to use the newly installed shared libraries before being
+installed themselves. However, the versions left in the build directory still
+use the uninstalled libraries.
+
+To build PCRE using static libraries only you must use --disable-shared when
+configuring it. For example:
+
+./configure --prefix=/usr/gnu --disable-shared
+
+Then run "make" in the usual way. Similarly, you can use --disable-static to
+build only shared libraries.
+
+
+Cross-compiling using autotools
+-------------------------------
+
+You can specify CC and CFLAGS in the normal way to the "configure" command, in
+order to cross-compile PCRE for some other host. However, you should NOT
+specify --enable-rebuild-chartables, because if you do, the dftables.c source
+file is compiled and run on the local host, in order to generate the inbuilt
+character tables (the pcre_chartables.c file). This will probably not work,
+because dftables.c needs to be compiled with the local compiler, not the cross
+compiler.
+
+When --enable-rebuild-chartables is not specified, pcre_chartables.c is created
+by making a copy of pcre_chartables.c.dist, which is a default set of tables
+that assumes ASCII code. Cross-compiling with the default tables should not be
+a problem.
+
+If you need to modify the character tables when cross-compiling, you should
+move pcre_chartables.c.dist out of the way, then compile dftables.c by hand and
+run it on the local host to make a new version of pcre_chartables.c.dist.
+Then when you cross-compile PCRE this new version of the tables will be used.
+
+
+Using HP's ANSI C++ compiler (aCC)
+----------------------------------
+
+Unless C++ support is disabled by specifying the "--disable-cpp" option of the
+"configure" script, you must include the "-AA" option in the CXXFLAGS
+environment variable in order for the C++ components to compile correctly.
+
+Also, note that the aCC compiler on PA-RISC platforms may have a defect whereby
+needed libraries fail to get included when specifying the "-AA" compiler
+option. If you experience unresolved symbols when linking the C++ programs,
+use the workaround of specifying the following environment variable prior to
+running the "configure" script:
+
+  CXXLDFLAGS="-lstd_v2 -lCsup_v2"
+
+
+Compiling in Tru64 using native compilers
+-----------------------------------------
+
+The following error may occur when compiling with native compilers in the Tru64
+operating system:
+
+  CXX    libpcrecpp_la-pcrecpp.lo
+cxx: Error: /usr/lib/cmplrs/cxx/V7.1-006/include/cxx/iosfwd, line 58: #error
+          directive: "cannot include iosfwd -- define __USE_STD_IOSTREAM to
+          override default - see section 7.1.2 of the C++ Using Guide"
+#error "cannot include iosfwd -- define __USE_STD_IOSTREAM to override default
+- see section 7.1.2 of the C++ Using Guide"
+
+This may be followed by other errors, complaining that 'namespace "std" has no
+member'. The solution to this is to add the line
+
+#define __USE_STD_IOSTREAM 1
+
+to the config.h file.
+
+
+Using Sun's compilers for Solaris
+---------------------------------
+
+A user reports that the following configurations work on Solaris 9 sparcv9 and
+Solaris 9 x86 (32-bit):
+
+  Solaris 9 sparcv9: ./configure --disable-cpp CC=/bin/cc CFLAGS="-m64 -g"
+  Solaris 9 x86:     ./configure --disable-cpp CC=/bin/cc CFLAGS="-g"
+
+
+Using PCRE from MySQL
+---------------------
+
+On systems where both PCRE and MySQL are installed, it is possible to make use
+of PCRE from within MySQL, as an alternative to the built-in pattern matching.
+There is a web page that tells you how to do this:
+
+  http://www.mysqludf.org/lib_mysqludf_preg/index.php
+
+
+Making new tarballs
+-------------------
+
+The command "make dist" creates three PCRE tarballs, in tar.gz, tar.bz2, and
+zip formats. The command "make distcheck" does the same, but then does a trial
+build of the new distribution to ensure that it works.
+
+If you have modified any of the man page sources in the doc directory, you
+should first run the PrepareRelease script before making a distribution. This
+script creates the .txt and HTML forms of the documentation from the man pages.
+
+
+Testing PCRE
+------------
+
+To test the basic PCRE library on a Unix-like system, run the RunTest script.
+There is another script called RunGrepTest that tests the options of the
+pcregrep command. If the C++ wrapper library is built, three test programs
+called pcrecpp_unittest, pcre_scanner_unittest, and pcre_stringpiece_unittest
+are also built. When JIT support is enabled, another test program called
+pcre_jit_test is built.
+
+Both the scripts and all the program tests are run if you obey "make check" or
+"make test". For other environments, see the instructions in
+NON-AUTOTOOLS-BUILD.
+
+The RunTest script runs the pcretest test program (which is documented in its
+own man page) on each of the relevant testinput files in the testdata
+directory, and compares the output with the contents of the corresponding
+testoutput files. RunTest uses a file called testtry to hold the main output
+from pcretest. Other files whose names begin with "test" are used as working
+files in some tests.
+
+Some tests are relevant only when certain build-time options were selected. For
+example, the tests for UTF-8/16/32 support are run only if --enable-utf was
+used. RunTest outputs a comment when it skips a test.
+
+Many of the tests that are not skipped are run up to three times. The second
+run forces pcre_study() to be called for all patterns except for a few in some
+tests that are marked "never study" (see the pcretest program for how this is
+done). If JIT support is available, the non-DFA tests are run a third time,
+this time with a forced pcre_study() with the PCRE_STUDY_JIT_COMPILE option.
+This testing can be suppressed by putting "nojit" on the RunTest command line.
+
+The entire set of tests is run once for each of the 8-bit, 16-bit and 32-bit
+libraries that are enabled. If you want to run just one set of tests, call
+RunTest with either the -8, -16 or -32 option.
+
+If valgrind is installed, you can run the tests under it by putting "valgrind"
+on the RunTest command line. To run pcretest on just one or more specific test
+files, give their numbers as arguments to RunTest, for example:
+
+  RunTest 2 7 11
+
+You can also specify ranges of tests such as 3-6 or 3- (meaning 3 to the
+end), or a number preceded by ~ to exclude a test. For example:
+
+  Runtest 3-15 ~10
+
+This runs tests 3 to 15, excluding test 10, and just ~13 runs all the tests
+except test 13. Whatever order the arguments are in, the tests are always run
+in numerical order.
+
+You can also call RunTest with the single argument "list" to cause it to output
+a list of tests.
+
+The first test file can be fed directly into the perltest.pl script to check
+that Perl gives the same results. The only difference you should see is in the
+first few lines, where the Perl version is given instead of the PCRE version.
+
+The second set of tests check pcre_fullinfo(), pcre_study(),
+pcre_copy_substring(), pcre_get_substring(), pcre_get_substring_list(), error
+detection, and run-time flags that are specific to PCRE, as well as the POSIX
+wrapper API. It also uses the debugging flags to check some of the internals of
+pcre_compile().
+
+If you build PCRE with a locale setting that is not the standard C locale, the
+character tables may be different (see next paragraph). In some cases, this may
+cause failures in the second set of tests. For example, in a locale where the
+isprint() function yields TRUE for characters in the range 128-255, the use of
+[:isascii:] inside a character class defines a different set of characters, and
+this shows up in this test as a difference in the compiled code, which is being
+listed for checking. Where the comparison test output contains [\x00-\x7f] the
+test will contain [\x00-\xff], and similarly in some other cases. This is not a
+bug in PCRE.
+
+The third set of tests checks pcre_maketables(), the facility for building a
+set of character tables for a specific locale and using them instead of the
+default tables. The tests make use of the "fr_FR" (French) locale. Before
+running the test, the script checks for the presence of this locale by running
+the "locale" command. If that command fails, or if it doesn't include "fr_FR"
+in the list of available locales, the third test cannot be run, and a comment
+is output to say why. If running this test produces instances of the error
+
+  ** Failed to set locale "fr_FR"
+
+in the comparison output, it means that locale is not available on your system,
+despite being listed by "locale". This does not mean that PCRE is broken.
+
+[If you are trying to run this test on Windows, you may be able to get it to
+work by changing "fr_FR" to "french" everywhere it occurs. Alternatively, use
+RunTest.bat. The version of RunTest.bat included with PCRE 7.4 and above uses
+Windows versions of test 2. More info on using RunTest.bat is included in the
+document entitled NON-UNIX-USE.]
+
+The fourth and fifth tests check the UTF-8/16/32 support and error handling and
+internal UTF features of PCRE that are not relevant to Perl, respectively. The
+sixth and seventh tests do the same for Unicode character properties support.
+
+The eighth, ninth, and tenth tests check the pcre_dfa_exec() alternative
+matching function, in non-UTF-8/16/32 mode, UTF-8/16/32 mode, and UTF-8/16/32
+mode with Unicode property support, respectively.
+
+The eleventh test checks some internal offsets and code size features; it is
+run only when the default "link size" of 2 is set (in other cases the sizes
+change) and when Unicode property support is enabled.
+
+The twelfth test is run only when JIT support is available, and the thirteenth
+test is run only when JIT support is not available. They test some JIT-specific
+features such as information output from pcretest about JIT compilation.
+
+The fourteenth, fifteenth, and sixteenth tests are run only in 8-bit mode, and
+the seventeenth, eighteenth, and nineteenth tests are run only in 16/32-bit
+mode. These are tests that generate different output in the two modes. They are
+for general cases, UTF-8/16/32 support, and Unicode property support,
+respectively.
+
+The twentieth test is run only in 16/32-bit mode. It tests some specific
+16/32-bit features of the DFA matching engine.
+
+The twenty-first and twenty-second tests are run only in 16/32-bit mode, when
+the link size is set to 2 for the 16-bit library. They test reloading
+pre-compiled patterns.
+
+The twenty-third and twenty-fourth tests are run only in 16-bit mode. They are
+for general cases, and UTF-16 support, respectively.
+
+The twenty-fifth and twenty-sixth tests are run only in 32-bit mode. They are
+for general cases, and UTF-32 support, respectively.
+
+
+Character tables
+----------------
+
+For speed, PCRE uses four tables for manipulating and identifying characters
+whose code point values are less than 256. The final argument of the
+pcre_compile() function is a pointer to a block of memory containing the
+concatenated tables. A call to pcre_maketables() can be used to generate a set
+of tables in the current locale. If the final argument for pcre_compile() is
+passed as NULL, a set of default tables that is built into the binary is used.
+
+The source file called pcre_chartables.c contains the default set of tables. By
+default, this is created as a copy of pcre_chartables.c.dist, which contains
+tables for ASCII coding. However, if --enable-rebuild-chartables is specified
+for ./configure, a different version of pcre_chartables.c is built by the
+program dftables (compiled from dftables.c), which uses the ANSI C character
+handling functions such as isalnum(), isalpha(), isupper(), islower(), etc. to
+build the table sources. This means that the default C locale which is set for
+your system will control the contents of these default tables. You can change
+the default tables by editing pcre_chartables.c and then re-building PCRE. If
+you do this, you should take care to ensure that the file does not get
+automatically re-generated. The best way to do this is to move
+pcre_chartables.c.dist out of the way and replace it with your customized
+tables.
+
+When the dftables program is run as a result of --enable-rebuild-chartables,
+it uses the default C locale that is set on your system. It does not pay
+attention to the LC_xxx environment variables. In other words, it uses the
+system's default locale rather than whatever the compiling user happens to have
+set. If you really do want to build a source set of character tables in a
+locale that is specified by the LC_xxx variables, you can run the dftables
+program by hand with the -L option. For example:
+
+  ./dftables -L pcre_chartables.c.special
+
+The first two 256-byte tables provide lower casing and case flipping functions,
+respectively. The next table consists of three 32-byte bit maps which identify
+digits, "word" characters, and white space, respectively. These are used when
+building 32-byte bit maps that represent character classes for code points less
+than 256.
+
+The final 256-byte table has bits indicating various character types, as
+follows:
+
+    1   white space character
+    2   letter
+    4   decimal digit
+    8   hexadecimal digit
+   16   alphanumeric or '_'
+  128   regular expression metacharacter or binary zero
+
+You should not alter the set of characters that contain the 128 bit, as that
+will cause PCRE to malfunction.
+
+
+File manifest
+-------------
+
+The distribution should contain the files listed below. Where a file name is
+given as pcre[16|32]_xxx it means that there are three files, one with the name
+pcre_xxx, one with the name pcre16_xx, and a third with the name pcre32_xxx.
+
+(A) Source files of the PCRE library functions and their headers:
+
+  dftables.c              auxiliary program for building pcre_chartables.c
+                          when --enable-rebuild-chartables is specified
+
+  pcre_chartables.c.dist  a default set of character tables that assume ASCII
+                          coding; used, unless --enable-rebuild-chartables is
+                          specified, by copying to pcre[16]_chartables.c
+
+  pcreposix.c                )
+  pcre[16|32]_byte_order.c   )
+  pcre[16|32]_compile.c      )
+  pcre[16|32]_config.c       )
+  pcre[16|32]_dfa_exec.c     )
+  pcre[16|32]_exec.c         )
+  pcre[16|32]_fullinfo.c     )
+  pcre[16|32]_get.c          ) sources for the functions in the library,
+  pcre[16|32]_globals.c      )   and some internal functions that they use
+  pcre[16|32]_jit_compile.c  )
+  pcre[16|32]_maketables.c   )
+  pcre[16|32]_newline.c      )
+  pcre[16|32]_refcount.c     )
+  pcre[16|32]_string_utils.c )
+  pcre[16|32]_study.c        )
+  pcre[16|32]_tables.c       )
+  pcre[16|32]_ucd.c          )
+  pcre[16|32]_version.c      )
+  pcre[16|32]_xclass.c       )
+  pcre_ord2utf8.c            )
+  pcre_valid_utf8.c          )
+  pcre16_ord2utf16.c         )
+  pcre16_utf16_utils.c       )
+  pcre16_valid_utf16.c       )
+  pcre32_utf32_utils.c       )
+  pcre32_valid_utf32.c       )
+
+  pcre[16|32]_printint.c     ) debugging function that is used by pcretest,
+                             )   and can also be #included in pcre_compile()
+
+  pcre.h.in               template for pcre.h when built by "configure"
+  pcreposix.h             header for the external POSIX wrapper API
+  pcre_internal.h         header for internal use
+  sljit/*                 16 files that make up the JIT compiler
+  ucp.h                   header for Unicode property handling
+
+  config.h.in             template for config.h, which is built by "configure"
+
+  pcrecpp.h               public header file for the C++ wrapper
+  pcrecpparg.h.in         template for another C++ header file
+  pcre_scanner.h          public header file for C++ scanner functions
+  pcrecpp.cc              )
+  pcre_scanner.cc         ) source for the C++ wrapper library
+
+  pcre_stringpiece.h.in   template for pcre_stringpiece.h, the header for the
+                            C++ stringpiece functions
+  pcre_stringpiece.cc     source for the C++ stringpiece functions
+
+(B) Source files for programs that use PCRE:
+
+  pcredemo.c              simple demonstration of coding calls to PCRE
+  pcregrep.c              source of a grep utility that uses PCRE
+  pcretest.c              comprehensive test program
+
+(C) Auxiliary files:
+
+  132html                 script to turn "man" pages into HTML
+  AUTHORS                 information about the author of PCRE
+  ChangeLog               log of changes to the code
+  CleanTxt                script to clean nroff output for txt man pages
+  Detrail                 script to remove trailing spaces
+  HACKING                 some notes about the internals of PCRE
+  INSTALL                 generic installation instructions
+  LICENCE                 conditions for the use of PCRE
+  COPYING                 the same, using GNU's standard name
+  Makefile.in             ) template for Unix Makefile, which is built by
+                          )   "configure"
+  Makefile.am             ) the automake input that was used to create
+                          )   Makefile.in
+  NEWS                    important changes in this release
+  NON-UNIX-USE            the previous name for NON-AUTOTOOLS-BUILD
+  NON-AUTOTOOLS-BUILD     notes on building PCRE without using autotools
+  PrepareRelease          script to make preparations for "make dist"
+  README                  this file
+  RunTest                 a Unix shell script for running tests
+  RunGrepTest             a Unix shell script for pcregrep tests
+  aclocal.m4              m4 macros (generated by "aclocal")
+  config.guess            ) files used by libtool,
+  config.sub              )   used only when building a shared library
+  configure               a configuring shell script (built by autoconf)
+  configure.ac            ) the autoconf input that was used to build
+                          )   "configure" and config.h
+  depcomp                 ) script to find program dependencies, generated by
+                          )   automake
+  doc/*.3                 man page sources for PCRE
+  doc/*.1                 man page sources for pcregrep and pcretest
+  doc/index.html.src      the base HTML page
+  doc/html/*              HTML documentation
+  doc/pcre.txt            plain text version of the man pages
+  doc/pcretest.txt        plain text documentation of test program
+  doc/perltest.txt        plain text documentation of Perl test program
+  install-sh              a shell script for installing files
+  libpcre16.pc.in         template for libpcre16.pc for pkg-config
+  libpcre32.pc.in         template for libpcre32.pc for pkg-config
+  libpcre.pc.in           template for libpcre.pc for pkg-config
+  libpcreposix.pc.in      template for libpcreposix.pc for pkg-config
+  libpcrecpp.pc.in        template for libpcrecpp.pc for pkg-config
+  ltmain.sh               file used to build a libtool script
+  missing                 ) common stub for a few missing GNU programs while
+                          )   installing, generated by automake
+  mkinstalldirs           script for making install directories
+  perltest.pl             Perl test program
+  pcre-config.in          source of script which retains PCRE information
+  pcre_jit_test.c         test program for the JIT compiler
+  pcrecpp_unittest.cc          )
+  pcre_scanner_unittest.cc     ) test programs for the C++ wrapper
+  pcre_stringpiece_unittest.cc )
+  testdata/testinput*     test data for main library tests
+  testdata/testoutput*    expected test results
+  testdata/grep*          input and output for pcregrep tests
+  testdata/*              other supporting test files
+
+(D) Auxiliary files for cmake support
+
+  cmake/COPYING-CMAKE-SCRIPTS
+  cmake/FindPackageHandleStandardArgs.cmake
+  cmake/FindEditline.cmake
+  cmake/FindReadline.cmake
+  CMakeLists.txt
+  config-cmake.h.in
+
+(E) Auxiliary files for VPASCAL
+
+  makevp.bat
+  makevp_c.txt
+  makevp_l.txt
+  pcregexp.pas
+
+(F) Auxiliary files for building PCRE "by hand"
+
+  pcre.h.generic          ) a version of the public PCRE header file
+                          )   for use in non-"configure" environments
+  config.h.generic        ) a version of config.h for use in non-"configure"
+                          )   environments
+
+(F) Miscellaneous
+
+  RunTest.bat            a script for running tests under Windows
+
+Philip Hazel
+Email local part: ph10
+Email domain: cam.ac.uk
+Last updated: 17 January 2014
diff --git a/libs/Pcre16/docs/doc/html/NON-AUTOTOOLS-BUILD.txt b/libs/Pcre16/docs/doc/html/NON-AUTOTOOLS-BUILD.txt
new file mode 100644
index 0000000000..cddf3e0699
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/NON-AUTOTOOLS-BUILD.txt
@@ -0,0 +1,764 @@
+Building PCRE without using autotools
+-------------------------------------
+
+This document contains the following sections:
+
+  General
+  Generic instructions for the PCRE C library
+  The C++ wrapper functions
+  Building for virtual Pascal
+  Stack size in Windows environments
+  Linking programs in Windows environments
+  Calling conventions in Windows environments
+  Comments about Win32 builds
+  Building PCRE on Windows with CMake
+  Use of relative paths with CMake on Windows
+  Testing with RunTest.bat
+  Building under Windows CE with Visual Studio 200x
+  Building under Windows with BCC5.5
+  Building using Borland C++ Builder 2007 (CB2007) and higher
+  Building PCRE on OpenVMS
+  Building PCRE on Stratus OpenVOS
+  Building PCRE on native z/OS and z/VM
+
+
+GENERAL
+
+I (Philip Hazel) have no experience of Windows or VMS sytems and how their
+libraries work. The items in the PCRE distribution and Makefile that relate to
+anything other than Linux systems are untested by me.
+
+There are some other comments and files (including some documentation in CHM
+format) in the Contrib directory on the FTP site:
+
+  ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre/Contrib
+
+The basic PCRE library consists entirely of code written in Standard C, and so
+should compile successfully on any system that has a Standard C compiler and
+library. The C++ wrapper functions are a separate issue (see below).
+
+The PCRE distribution includes a "configure" file for use by the configure/make
+(autotools) build system, as found in many Unix-like environments. The README
+file contains information about the options for "configure".
+
+There is also support for CMake, which some users prefer, especially in Windows
+environments, though it can also be run in Unix-like environments. See the
+section entitled "Building PCRE on Windows with CMake" below.
+
+Versions of config.h and pcre.h are distributed in the PCRE tarballs under the
+names config.h.generic and pcre.h.generic. These are provided for those who
+build PCRE without using "configure" or CMake. If you use "configure" or CMake,
+the .generic versions are not used.
+
+
+GENERIC INSTRUCTIONS FOR THE PCRE C LIBRARY
+
+The following are generic instructions for building the PCRE C library "by
+hand". If you are going to use CMake, this section does not apply to you; you
+can skip ahead to the CMake section.
+
+ (1) Copy or rename the file config.h.generic as config.h, and edit the macro
+     settings that it contains to whatever is appropriate for your environment.
+
+     In particular, you can alter the definition of the NEWLINE macro to
+     specify what character(s) you want to be interpreted as line terminators.
+     In an EBCDIC environment, you MUST change NEWLINE, because its default
+     value is 10, an ASCII LF. The usual EBCDIC newline character is 21 (0x15,
+     NL), though in some cases it may be 37 (0x25).
+
+     When you compile any of the PCRE modules, you must specify -DHAVE_CONFIG_H
+     to your compiler so that config.h is included in the sources.
+
+     An alternative approach is not to edit config.h, but to use -D on the
+     compiler command line to make any changes that you need to the
+     configuration options. In this case -DHAVE_CONFIG_H must not be set.
+
+     NOTE: There have been occasions when the way in which certain parameters
+     in config.h are used has changed between releases. (In the configure/make
+     world, this is handled automatically.) When upgrading to a new release,
+     you are strongly advised to review config.h.generic before re-using what
+     you had previously.
+
+ (2) Copy or rename the file pcre.h.generic as pcre.h.
+
+ (3) EITHER:
+       Copy or rename file pcre_chartables.c.dist as pcre_chartables.c.
+
+     OR:
+       Compile dftables.c as a stand-alone program (using -DHAVE_CONFIG_H if
+       you have set up config.h), and then run it with the single argument
+       "pcre_chartables.c". This generates a set of standard character tables
+       and writes them to that file. The tables are generated using the default
+       C locale for your system. If you want to use a locale that is specified
+       by LC_xxx environment variables, add the -L option to the dftables
+       command. You must use this method if you are building on a system that
+       uses EBCDIC code.
+
+     The tables in pcre_chartables.c are defaults. The caller of PCRE can
+     specify alternative tables at run time.
+
+ (4) Ensure that you have the following header files:
+
+       pcre_internal.h
+       ucp.h
+
+ (5) For an 8-bit library, compile the following source files, setting
+     -DHAVE_CONFIG_H as a compiler option if you have set up config.h with your
+     configuration, or else use other -D settings to change the configuration
+     as required.
+
+       pcre_byte_order.c
+       pcre_chartables.c
+       pcre_compile.c
+       pcre_config.c
+       pcre_dfa_exec.c
+       pcre_exec.c
+       pcre_fullinfo.c
+       pcre_get.c
+       pcre_globals.c
+       pcre_jit_compile.c
+       pcre_maketables.c
+       pcre_newline.c
+       pcre_ord2utf8.c
+       pcre_refcount.c
+       pcre_string_utils.c
+       pcre_study.c
+       pcre_tables.c
+       pcre_ucd.c
+       pcre_valid_utf8.c
+       pcre_version.c
+       pcre_xclass.c
+
+     Make sure that you include -I. in the compiler command (or equivalent for
+     an unusual compiler) so that all included PCRE header files are first
+     sought in the current directory. Otherwise you run the risk of picking up
+     a previously-installed file from somewhere else.
+
+     Note that you must still compile pcre_jit_compile.c, even if you have not
+     defined SUPPORT_JIT in config.h, because when JIT support is not
+     configured, dummy functions are compiled. When JIT support IS configured,
+     pcre_jit_compile.c #includes sources from the sljit subdirectory, where
+     there should be 16 files, all of whose names begin with "sljit".
+
+ (6) Now link all the compiled code into an object library in whichever form
+     your system keeps such libraries. This is the basic PCRE C 8-bit library.
+     If your system has static and shared libraries, you may have to do this
+     once for each type.
+
+ (7) If you want to build a 16-bit library (as well as, or instead of the 8-bit
+     or 32-bit libraries) repeat steps 5-6 with the following files:
+
+       pcre16_byte_order.c
+       pcre16_chartables.c
+       pcre16_compile.c
+       pcre16_config.c
+       pcre16_dfa_exec.c
+       pcre16_exec.c
+       pcre16_fullinfo.c
+       pcre16_get.c
+       pcre16_globals.c
+       pcre16_jit_compile.c
+       pcre16_maketables.c
+       pcre16_newline.c
+       pcre16_ord2utf16.c
+       pcre16_refcount.c
+       pcre16_string_utils.c
+       pcre16_study.c
+       pcre16_tables.c
+       pcre16_ucd.c
+       pcre16_utf16_utils.c
+       pcre16_valid_utf16.c
+       pcre16_version.c
+       pcre16_xclass.c
+
+ (8) If you want to build a 32-bit library (as well as, or instead of the 8-bit
+     or 16-bit libraries) repeat steps 5-6 with the following files:
+
+       pcre32_byte_order.c
+       pcre32_chartables.c
+       pcre32_compile.c
+       pcre32_config.c
+       pcre32_dfa_exec.c
+       pcre32_exec.c
+       pcre32_fullinfo.c
+       pcre32_get.c
+       pcre32_globals.c
+       pcre32_jit_compile.c
+       pcre32_maketables.c
+       pcre32_newline.c
+       pcre32_ord2utf32.c
+       pcre32_refcount.c
+       pcre32_string_utils.c
+       pcre32_study.c
+       pcre32_tables.c
+       pcre32_ucd.c
+       pcre32_utf32_utils.c
+       pcre32_valid_utf32.c
+       pcre32_version.c
+       pcre32_xclass.c
+
+ (9) If you want to build the POSIX wrapper functions (which apply only to the
+     8-bit library), ensure that you have the pcreposix.h file and then compile
+     pcreposix.c (remembering -DHAVE_CONFIG_H if necessary). Link the result
+     (on its own) as the pcreposix library.
+
+(10) The pcretest program can be linked with any combination of the 8-bit,
+     16-bit and 32-bit libraries (depending on what you selected in config.h).
+     Compile pcretest.c and pcre_printint.c (again, don't forget
+     -DHAVE_CONFIG_H) and link them together with the appropriate library/ies.
+     If you compiled an 8-bit library, pcretest also needs the pcreposix
+     wrapper library unless you compiled it with -DNOPOSIX.
+
+(11) Run pcretest on the testinput files in the testdata directory, and check
+     that the output matches the corresponding testoutput files. There are
+     comments about what each test does in the section entitled "Testing PCRE"
+     in the README file. If you compiled more than one of the 8-bit, 16-bit and
+     32-bit libraries, you need to run pcretest with the -16 option to do
+     16-bit tests and with the -32 option to do 32-bit tests.
+
+     Some tests are relevant only when certain build-time options are selected.
+     For example, test 4 is for UTF-8/UTF-16/UTF-32 support, and will not run
+     if you have built PCRE without it. See the comments at the start of each
+     testinput file. If you have a suitable Unix-like shell, the RunTest script
+     will run the appropriate tests for you. The command "RunTest list" will
+     output a list of all the tests.
+
+     Note that the supplied files are in Unix format, with just LF characters
+     as line terminators. You may need to edit them to change this if your
+     system uses a different convention. If you are using Windows, you probably
+     should use the wintestinput3 file instead of testinput3 (and the
+     corresponding output file). This is a locale test; wintestinput3 sets the
+     locale to "french" rather than "fr_FR", and there some minor output
+     differences.
+
+(12) If you have built PCRE with SUPPORT_JIT, the JIT features will be tested
+     by the testdata files. However, you might also like to build and run
+     the freestanding JIT test program, pcre_jit_test.c.
+
+(13) If you want to use the pcregrep command, compile and link pcregrep.c; it
+     uses only the basic 8-bit PCRE library (it does not need the pcreposix
+     library).
+
+
+THE C++ WRAPPER FUNCTIONS
+
+The PCRE distribution also contains some C++ wrapper functions and tests,
+applicable to the 8-bit library, which were contributed by Google Inc. On a
+system that can use "configure" and "make", the functions are automatically
+built into a library called pcrecpp. It should be straightforward to compile
+the .cc files manually on other systems. The files called xxx_unittest.cc are
+test programs for each of the corresponding xxx.cc files.
+
+
+BUILDING FOR VIRTUAL PASCAL
+
+A script for building PCRE using Borland's C++ compiler for use with VPASCAL
+was contributed by Alexander Tokarev. Stefan Weber updated the script and added
+additional files. The following files in the distribution are for building PCRE
+for use with VP/Borland: makevp_c.txt, makevp_l.txt, makevp.bat, pcregexp.pas.
+
+
+STACK SIZE IN WINDOWS ENVIRONMENTS
+
+The default processor stack size of 1Mb in some Windows environments is too
+small for matching patterns that need much recursion. In particular, test 2 may
+fail because of this. Normally, running out of stack causes a crash, but there
+have been cases where the test program has just died silently. See your linker
+documentation for how to increase stack size if you experience problems. The
+Linux default of 8Mb is a reasonable choice for the stack, though even that can
+be too small for some pattern/subject combinations.
+
+PCRE has a compile configuration option to disable the use of stack for
+recursion so that heap is used instead. However, pattern matching is
+significantly slower when this is done. There is more about stack usage in the
+"pcrestack" documentation.
+
+
+LINKING PROGRAMS IN WINDOWS ENVIRONMENTS
+
+If you want to statically link a program against a PCRE library in the form of
+a non-dll .a file, you must define PCRE_STATIC before including pcre.h or
+pcrecpp.h, otherwise the pcre_malloc() and pcre_free() exported functions will
+be declared __declspec(dllimport), with unwanted results.
+
+
+CALLING CONVENTIONS IN WINDOWS ENVIRONMENTS
+
+It is possible to compile programs to use different calling conventions using
+MSVC. Search the web for "calling conventions" for more information. To make it
+easier to change the calling convention for the exported functions in the
+PCRE library, the macro PCRE_CALL_CONVENTION is present in all the external
+definitions. It can be set externally when compiling (e.g. in CFLAGS). If it is
+not set, it defaults to empty; the default calling convention is then used
+(which is what is wanted most of the time).
+
+
+COMMENTS ABOUT WIN32 BUILDS (see also "BUILDING PCRE ON WINDOWS WITH CMAKE")
+
+There are two ways of building PCRE using the "configure, make, make install"
+paradigm on Windows systems: using MinGW or using Cygwin. These are not at all
+the same thing; they are completely different from each other. There is also
+support for building using CMake, which some users find a more straightforward
+way of building PCRE under Windows.
+
+The MinGW home page (http://www.mingw.org/) says this:
+
+  MinGW: A collection of freely available and freely distributable Windows
+  specific header files and import libraries combined with GNU toolsets that
+  allow one to produce native Windows programs that do not rely on any
+  3rd-party C runtime DLLs.
+
+The Cygwin home page (http://www.cygwin.com/) says this:
+
+  Cygwin is a Linux-like environment for Windows. It consists of two parts:
+
+  . A DLL (cygwin1.dll) which acts as a Linux API emulation layer providing
+    substantial Linux API functionality
+
+  . A collection of tools which provide Linux look and feel.
+
+  The Cygwin DLL currently works with all recent, commercially released x86 32
+  bit and 64 bit versions of Windows, with the exception of Windows CE.
+
+On both MinGW and Cygwin, PCRE should build correctly using:
+
+  ./configure && make && make install
+
+This should create two libraries called libpcre and libpcreposix, and, if you
+have enabled building the C++ wrapper, a third one called libpcrecpp. These are
+independent libraries: when you link with libpcreposix or libpcrecpp you must
+also link with libpcre, which contains the basic functions. (Some earlier
+releases of PCRE included the basic libpcre functions in libpcreposix. This no
+longer happens.)
+
+A user submitted a special-purpose patch that makes it easy to create
+"pcre.dll" under mingw32 using the "msys" environment. It provides "pcre.dll"
+as a special target. If you use this target, no other files are built, and in
+particular, the pcretest and pcregrep programs are not built. An example of how
+this might be used is:
+
+  ./configure --enable-utf --disable-cpp CFLAGS="-03 -s"; make pcre.dll
+
+Using Cygwin's compiler generates libraries and executables that depend on
+cygwin1.dll. If a library that is generated this way is distributed,
+cygwin1.dll has to be distributed as well. Since cygwin1.dll is under the GPL
+licence, this forces not only PCRE to be under the GPL, but also the entire
+application. A distributor who wants to keep their own code proprietary must
+purchase an appropriate Cygwin licence.
+
+MinGW has no such restrictions. The MinGW compiler generates a library or
+executable that can run standalone on Windows without any third party dll or
+licensing issues.
+
+But there is more complication:
+
+If a Cygwin user uses the -mno-cygwin Cygwin gcc flag, what that really does is
+to tell Cygwin's gcc to use the MinGW gcc. Cygwin's gcc is only acting as a
+front end to MinGW's gcc (if you install Cygwin's gcc, you get both Cygwin's
+gcc and MinGW's gcc). So, a user can:
+
+. Build native binaries by using MinGW or by getting Cygwin and using
+  -mno-cygwin.
+
+. Build binaries that depend on cygwin1.dll by using Cygwin with the normal
+  compiler flags.
+
+The test files that are supplied with PCRE are in UNIX format, with LF
+characters as line terminators. Unless your PCRE library uses a default newline
+option that includes LF as a valid newline, it may be necessary to change the
+line terminators in the test files to get some of the tests to work.
+
+
+BUILDING PCRE ON WINDOWS WITH CMAKE
+
+CMake is an alternative configuration facility that can be used instead of
+"configure". CMake creates project files (make files, solution files, etc.)
+tailored to numerous development environments, including Visual Studio,
+Borland, Msys, MinGW, NMake, and Unix. If possible, use short paths with no
+spaces in the names for your CMake installation and your PCRE source and build
+directories.
+
+The following instructions were contributed by a PCRE user. If they are not
+followed exactly, errors may occur. In the event that errors do occur, it is
+recommended that you delete the CMake cache before attempting to repeat the
+CMake build process. In the CMake GUI, the cache can be deleted by selecting
+"File > Delete Cache".
+
+1.  Install the latest CMake version available from http://www.cmake.org/, and
+    ensure that cmake\bin is on your path.
+
+2.  Unzip (retaining folder structure) the PCRE source tree into a source
+    directory such as C:\pcre. You should ensure your local date and time
+    is not earlier than the file dates in your source dir if the release is
+    very new.
+
+3.  Create a new, empty build directory, preferably a subdirectory of the
+    source dir. For example, C:\pcre\pcre-xx\build.
+
+4.  Run cmake-gui from the Shell envirornment of your build tool, for example,
+    Msys for Msys/MinGW or Visual Studio Command Prompt for VC/VC++. Do not try
+    to start Cmake from the Windows Start menu, as this can lead to errors.
+
+5.  Enter C:\pcre\pcre-xx and C:\pcre\pcre-xx\build for the source and build
+    directories, respectively.
+
+6.  Hit the "Configure" button.
+
+7.  Select the particular IDE / build tool that you are using (Visual
+    Studio, MSYS makefiles, MinGW makefiles, etc.)
+
+8.  The GUI will then list several configuration options. This is where
+    you can enable UTF-8 support or other PCRE optional features.
+
+9.  Hit "Configure" again. The adjacent "Generate" button should now be
+    active.
+
+10. Hit "Generate".
+
+11. The build directory should now contain a usable build system, be it a
+    solution file for Visual Studio, makefiles for MinGW, etc. Exit from
+    cmake-gui and use the generated build system with your compiler or IDE.
+    E.g., for MinGW you can run "make", or for Visual Studio, open the PCRE
+    solution, select the desired configuration (Debug, or Release, etc.) and
+    build the ALL_BUILD project.
+
+12. If during configuration with cmake-gui you've elected to build the test
+    programs, you can execute them by building the test project. E.g., for
+    MinGW: "make test"; for Visual Studio build the RUN_TESTS project. The
+    most recent build configuration is targeted by the tests. A summary of
+    test results is presented. Complete test output is subsequently
+    available for review in Testing\Temporary under your build dir.
+
+
+USE OF RELATIVE PATHS WITH CMAKE ON WINDOWS
+
+A PCRE user comments as follows: I thought that others may want to know the
+current state of CMAKE_USE_RELATIVE_PATHS support on Windows. Here it is:
+
+-- AdditionalIncludeDirectories is only partially modified (only the
+   first path - see below)
+-- Only some of the contained file paths are modified - shown below for
+   pcre.vcproj
+-- It properly modifies
+
+I am sure CMake people can fix that if they want to. Until then one will
+need to replace existing absolute paths in project files with relative
+paths manually (e.g. from VS) - relative to project file location. I did
+just that before being told to try CMAKE_USE_RELATIVE_PATHS. Not a big
+deal.
+
+AdditionalIncludeDirectories="E:\builds\pcre\build;E:\builds\pcre\pcre-7.5;"
+AdditionalIncludeDirectories=".;E:\builds\pcre\pcre-7.5;"
+
+RelativePath="pcre.h"
+RelativePath="pcre_chartables.c"
+RelativePath="pcre_chartables.c.rule"
+
+
+TESTING WITH RUNTEST.BAT
+
+If configured with CMake, building the test project ("make test" or building
+ALL_TESTS in Visual Studio) creates (and runs) pcre_test.bat (and depending
+on your configuration options, possibly other test programs) in the build
+directory. Pcre_test.bat runs RunTest.Bat with correct source and exe paths.
+
+For manual testing with RunTest.bat, provided the build dir is a subdirectory
+of the source directory: Open command shell window. Chdir to the location
+of your pcretest.exe and pcregrep.exe programs. Call RunTest.bat with
+"..\RunTest.Bat" or "..\..\RunTest.bat" as appropriate.
+
+To run only a particular test with RunTest.Bat provide a test number argument.
+
+Otherwise:
+
+1. Copy RunTest.bat into the directory where pcretest.exe and pcregrep.exe
+   have been created.
+
+2. Edit RunTest.bat to indentify the full or relative location of
+   the pcre source (wherein which the testdata folder resides), e.g.:
+
+   set srcdir=C:\pcre\pcre-8.20
+
+3. In a Windows command environment, chdir to the location of your bat and
+   exe programs.
+
+4. Run RunTest.bat. Test outputs will automatically be compared to expected
+   results, and discrepancies will be identified in the console output.
+
+To independently test the just-in-time compiler, run pcre_jit_test.exe.
+To test pcrecpp, run pcrecpp_unittest.exe, pcre_stringpiece_unittest.exe and
+pcre_scanner_unittest.exe.
+
+
+BUILDING UNDER WINDOWS CE WITH VISUAL STUDIO 200x
+
+Vincent Richomme sent a zip archive of files to help with this process. They
+can be found in the file "pcre-vsbuild.zip" in the Contrib directory of the FTP
+site.
+
+
+BUILDING UNDER WINDOWS WITH BCC5.5
+
+Michael Roy sent these comments about building PCRE under Windows with BCC5.5:
+
+Some of the core BCC libraries have a version of PCRE from 1998 built in, which
+can lead to pcre_exec() giving an erroneous PCRE_ERROR_NULL from a version
+mismatch. I'm including an easy workaround below, if you'd like to include it
+in the non-unix instructions:
+
+When linking a project with BCC5.5, pcre.lib must be included before any of the
+libraries cw32.lib, cw32i.lib, cw32mt.lib, and cw32mti.lib on the command line.
+
+
+BUILDING USING BORLAND C++ BUILDER 2007 (CB2007) AND HIGHER
+
+A PCRE user sent these comments about this environment (see also the comment
+from another user that follows them):
+
+The XE versions of C++ Builder come with a RegularExpressionsCore class which
+contain a version of TPerlRegEx. However, direct use of the C PCRE library may
+be desirable.
+
+The default makevp.bat, however, supplied with PCRE builds a version of PCRE
+that is not usable with any version of C++ Builder because the compiler ships
+with an embedded version of PCRE, version 2.01 from 1998! [See also the note
+about BCC5.5 above.] If you want to use PCRE you'll need to rename the
+functions (pcre_compile to pcre_compile_bcc, etc) or do as I have done and just
+use the 16 bit versions. I'm using std::wstring everywhere anyway. Since the
+embedded version of PCRE does not have the 16 bit function names, there is no
+conflict.
+
+Building PCRE using a C++ Builder static library project file (recommended):
+
+1. Rename or remove pcre.h, pcreposi.h, and pcreposix.h from your C++ Builder
+original include path.
+
+2. Download PCRE from pcre.org and extract to a directory.
+
+3. Rename pcre_chartables.c.dist to pcre_chartables.c, pcre.h.generic to
+pcre.h, and config.h.generic to config.h.
+
+4. Edit pcre.h and pcre_config.c so that they include config.h.
+
+5. Edit config.h like so:
+
+Comment out the following lines:
+#define PACKAGE "pcre"
+#define PACKAGE_BUGREPORT ""
+#define PACKAGE_NAME "PCRE"
+#define PACKAGE_STRING "PCRE 8.32"
+#define PACKAGE_TARNAME "pcre"
+#define PACKAGE_URL ""
+#define PACKAGE_VERSION "8.32"
+
+Add the following lines:
+#ifndef SUPPORT_UTF
+#define SUPPORT_UTF 100 // any value is fine
+#endif
+
+#ifndef SUPPORT_UCP
+#define SUPPORT_UCP 101 // any value is fine
+#endif
+
+#ifndef SUPPORT_UCP
+#define SUPPORT_PCRE16 102 // any value is fine
+#endif
+
+#ifndef SUPPORT_UTF8
+#define SUPPORT_UTF8 103 // any value is fine
+#endif
+
+6. Build a C++ Builder project using the IDE. Go to File / New / Other and
+choose Static Library. You can name it pcre.cbproj or whatever. Now set your
+paths by going to Project / Options. Set the Include path. Do this from the
+"Base" option to apply to both Release and Debug builds. Now add the following
+files to the project:
+
+pcre.h
+pcre16_byte_order.c
+pcre16_chartables.c
+pcre16_compile.c
+pcre16_config.c
+pcre16_dfa_exec.c
+pcre16_exec.c
+pcre16_fullinfo.c
+pcre16_get.c
+pcre16_globals.c
+pcre16_maketables.c
+pcre16_newline.c
+pcre16_ord2utf16.c
+pcre16_printint.c
+pcre16_refcount.c
+pcre16_string_utils.c
+pcre16_study.c
+pcre16_tables.c
+pcre16_ucd.c
+pcre16_utf16_utils.c
+pcre16_valid_utf16.c
+pcre16_version.c
+pcre16_xclass.c
+
+//Optional
+pcre_version.c
+
+7. After compiling the .lib file, copy the .lib and header files to a project
+you want to use PCRE with. Enjoy.
+
+Optional ... Building PCRE using the makevp.bat file:
+
+1. Edit makevp_c.txt and makevp_l.txt and change all the names to the 16 bit
+versions.
+
+2. Edit makevp.bat and set the path to C++ Builder. Run makevp.bat.
+
+Another PCRE user added this comment:
+
+Another approach I successfully used for some years with BCB 5 and 6 was to
+make sure that include and library paths of PCRE are configured before the
+default paths of the IDE in the dialogs where one can manage those paths.
+Afterwards one can open the project files using a text editor and manually add
+the self created library for pcre itself, pcrecpp doesn't ship with the IDE, in
+the library nodes where the IDE manages its own libraries to link against in
+front of the IDE-own libraries. This way one can use the default PCRE function
+names without getting access violations on runtime.
+
+  <ALLLIB value="libpcre.lib $(LIBFILES) $(LIBRARIES) import32.lib cp32mt.lib"/>
+
+
+BUILDING PCRE ON OPENVMS
+
+Stephen Hoffman sent the following, in December 2012:
+
+"Here <http://labs.hoffmanlabs.com/node/1847> is a very short write-up on the
+OpenVMS port and here
+
+<http://labs.hoffmanlabs.com/labsnotes/pcre-vms-8_32.zip>
+
+is a zip with the OpenVMS files, and with one modified testing-related PCRE
+file." This is a port of PCRE 8.32.
+
+Earlier, Dan Mooney sent the following comments about building PCRE on OpenVMS.
+They relate to an older version of PCRE that used fewer source files, so the
+exact commands will need changing. See the current list of source files above.
+
+"It was quite easy to compile and link the library. I don't have a formal
+make file but the attached file [reproduced below] contains the OpenVMS DCL
+commands I used to build the library. I had to add #define
+POSIX_MALLOC_THRESHOLD 10 to pcre.h since it was not defined anywhere.
+
+The library was built on:
+O/S: HP OpenVMS v7.3-1
+Compiler: Compaq C v6.5-001-48BCD
+Linker: vA13-01
+
+The test results did not match 100% due to the issues you mention in your
+documentation regarding isprint(), iscntrl(), isgraph() and ispunct(). I
+modified some of the character tables temporarily and was able to get the
+results to match. Tests using the fr locale did not match since I don't have
+that locale loaded. The study size was always reported to be 3 less than the
+value in the standard test output files."
+
+=========================
+$! This DCL procedure builds PCRE on OpenVMS
+$!
+$! I followed the instructions in the non-unix-use file in the distribution.
+$!
+$ COMPILE == "CC/LIST/NOMEMBER_ALIGNMENT/PREFIX_LIBRARY_ENTRIES=ALL_ENTRIES
+$ COMPILE DFTABLES.C
+$ LINK/EXE=DFTABLES.EXE DFTABLES.OBJ
+$ RUN DFTABLES.EXE/OUTPUT=CHARTABLES.C
+$ COMPILE MAKETABLES.C
+$ COMPILE GET.C
+$ COMPILE STUDY.C
+$! I had to set POSIX_MALLOC_THRESHOLD to 10 in PCRE.H since the symbol
+$! did not seem to be defined anywhere.
+$! I edited pcre.h and added #DEFINE SUPPORT_UTF8 to enable UTF8 support.
+$ COMPILE PCRE.C
+$ LIB/CREATE PCRE MAKETABLES.OBJ, GET.OBJ, STUDY.OBJ, PCRE.OBJ
+$! I had to set POSIX_MALLOC_THRESHOLD to 10 in PCRE.H since the symbol
+$! did not seem to be defined anywhere.
+$ COMPILE PCREPOSIX.C
+$ LIB/CREATE PCREPOSIX PCREPOSIX.OBJ
+$ COMPILE PCRETEST.C
+$ LINK/EXE=PCRETEST.EXE PCRETEST.OBJ, PCRE/LIB, PCREPOSIX/LIB
+$! C programs that want access to command line arguments must be
+$! defined as a symbol
+$ PCRETEST :== "$ SYS$ROADSUSERS:[DMOONEY.REGEXP]PCRETEST.EXE"
+$! Arguments must be enclosed in quotes.
+$ PCRETEST "-C"
+$! Test results:
+$!
+$!   The test results did not match 100%. The functions isprint(), iscntrl(),
+$!   isgraph() and ispunct() on OpenVMS must not produce the same results
+$!   as the system that built the test output files provided with the
+$!   distribution.
+$!
+$!   The study size did not match and was always 3 less on OpenVMS.
+$!
+$!   Locale could not be set to fr
+$!
+=========================
+
+
+BUILDING PCRE ON STRATUS OPENVOS
+
+These notes on the port of PCRE to VOS (lightly edited) were supplied by
+Ashutosh Warikoo, whose email address has the local part awarikoo and the
+domain nse.co.in. The port was for version 7.9 in August 2009.
+
+1.   Building PCRE
+
+I built pcre on OpenVOS Release 17.0.1at using GNU Tools 3.4a without any
+problems. I used the following packages to build PCRE:
+
+  ftp://ftp.stratus.com/pub/vos/posix/ga/posix.save.evf.gz
+
+Please read and follow the instructions that come with these packages. To start
+the build of pcre, from the root of the package type:
+
+  ./build.sh
+
+2. Installing PCRE
+
+Once you have successfully built PCRE, login to the SysAdmin group, switch to
+the root user, and type
+
+  [ !create_dir (master_disk)>usr   --if needed ]
+  [ !create_dir (master_disk)>usr>local   --if needed ]
+    !gmake install
+
+This installs PCRE and its man pages into /usr/local. You can add
+(master_disk)>usr>local>bin to your command search paths, or if you are in
+BASH, add /usr/local/bin to the PATH environment variable.
+
+4. Restrictions
+
+This port requires readline library optionally. However during the build I
+faced some yet unexplored errors while linking with readline. As it was an
+optional component I chose to disable it.
+
+5. Known Problems
+
+I ran the test suite, but you will have to be your own judge of whether this
+command, and this port, suits your purposes. If you find any problems that
+appear to be related to the port itself, please let me know. Please see the
+build.log file in the root of the package also.
+
+
+BUILDING PCRE ON NATIVE Z/OS AND Z/VM
+
+z/OS and z/VM are operating systems for mainframe computers, produced by IBM.
+The character code used is EBCDIC, not ASCII or Unicode. In z/OS, UNIX APIs and
+applications can be supported through UNIX System Services, and in such an
+environment PCRE can be built in the same way as in other systems. However, in
+native z/OS (without UNIX System Services) and in z/VM, special ports are
+required. For details, please see this web site:
+
+  http://www.zaconsultants.net
+
+There is also a mirror here:
+
+  http://www.vsoft-software.com/downloads.html
+
+==========================
+Last Updated: 14 May 2013
diff --git a/libs/Pcre16/docs/doc/html/README.txt b/libs/Pcre16/docs/doc/html/README.txt
new file mode 100644
index 0000000000..88f2dfd4ef
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/README.txt
@@ -0,0 +1,991 @@
+README file for PCRE (Perl-compatible regular expression library)
+-----------------------------------------------------------------
+
+The latest release of PCRE is always available in three alternative formats
+from:
+
+  ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre/pcre-xxx.tar.gz
+  ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre/pcre-xxx.tar.bz2
+  ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre/pcre-xxx.zip
+
+There is a mailing list for discussion about the development of PCRE at
+pcre-dev@exim.org. You can access the archives and subscribe or manage your
+subscription here:
+
+   https://lists.exim.org/mailman/listinfo/pcre-dev
+
+Please read the NEWS file if you are upgrading from a previous release.
+The contents of this README file are:
+
+  The PCRE APIs
+  Documentation for PCRE
+  Contributions by users of PCRE
+  Building PCRE on non-Unix-like systems
+  Building PCRE without using autotools
+  Building PCRE using autotools
+  Retrieving configuration information
+  Shared libraries
+  Cross-compiling using autotools
+  Using HP's ANSI C++ compiler (aCC)
+  Compiling in Tru64 using native compilers
+  Using Sun's compilers for Solaris
+  Using PCRE from MySQL
+  Making new tarballs
+  Testing PCRE
+  Character tables
+  File manifest
+
+
+The PCRE APIs
+-------------
+
+PCRE is written in C, and it has its own API. There are three sets of
+functions, one for the 8-bit library, which processes strings of bytes, one for
+the 16-bit library, which processes strings of 16-bit values, and one for the
+32-bit library, which processes strings of 32-bit values. The distribution also
+includes a set of C++ wrapper functions (see the pcrecpp man page for details),
+courtesy of Google Inc., which can be used to call the 8-bit PCRE library from
+C++.
+
+In addition, there is a set of C wrapper functions (again, just for the 8-bit
+library) that are based on the POSIX regular expression API (see the pcreposix
+man page). These end up in the library called libpcreposix. Note that this just
+provides a POSIX calling interface to PCRE; the regular expressions themselves
+still follow Perl syntax and semantics. The POSIX API is restricted, and does
+not give full access to all of PCRE's facilities.
+
+The header file for the POSIX-style functions is called pcreposix.h. The
+official POSIX name is regex.h, but I did not want to risk possible problems
+with existing files of that name by distributing it that way. To use PCRE with
+an existing program that uses the POSIX API, pcreposix.h will have to be
+renamed or pointed at by a link.
+
+If you are using the POSIX interface to PCRE and there is already a POSIX regex
+library installed on your system, as well as worrying about the regex.h header
+file (as mentioned above), you must also take care when linking programs to
+ensure that they link with PCRE's libpcreposix library. Otherwise they may pick
+up the POSIX functions of the same name from the other library.
+
+One way of avoiding this confusion is to compile PCRE with the addition of
+-Dregcomp=PCREregcomp (and similarly for the other POSIX functions) to the
+compiler flags (CFLAGS if you are using "configure" -- see below). This has the
+effect of renaming the functions so that the names no longer clash. Of course,
+you have to do the same thing for your applications, or write them using the
+new names.
+
+
+Documentation for PCRE
+----------------------
+
+If you install PCRE in the normal way on a Unix-like system, you will end up
+with a set of man pages whose names all start with "pcre". The one that is just
+called "pcre" lists all the others. In addition to these man pages, the PCRE
+documentation is supplied in two other forms:
+
+  1. There are files called doc/pcre.txt, doc/pcregrep.txt, and
+     doc/pcretest.txt in the source distribution. The first of these is a
+     concatenation of the text forms of all the section 3 man pages except
+     the listing of pcredemo.c and those that summarize individual functions.
+     The other two are the text forms of the section 1 man pages for the
+     pcregrep and pcretest commands. These text forms are provided for ease of
+     scanning with text editors or similar tools. They are installed in
+     <prefix>/share/doc/pcre, where <prefix> is the installation prefix
+     (defaulting to /usr/local).
+
+  2. A set of files containing all the documentation in HTML form, hyperlinked
+     in various ways, and rooted in a file called index.html, is distributed in
+     doc/html and installed in <prefix>/share/doc/pcre/html.
+
+Users of PCRE have contributed files containing the documentation for various
+releases in CHM format. These can be found in the Contrib directory of the FTP
+site (see next section).
+
+
+Contributions by users of PCRE
+------------------------------
+
+You can find contributions from PCRE users in the directory
+
+  ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre/Contrib
+
+There is a README file giving brief descriptions of what they are. Some are
+complete in themselves; others are pointers to URLs containing relevant files.
+Some of this material is likely to be well out-of-date. Several of the earlier
+contributions provided support for compiling PCRE on various flavours of
+Windows (I myself do not use Windows). Nowadays there is more Windows support
+in the standard distribution, so these contibutions have been archived.
+
+A PCRE user maintains downloadable Windows binaries of the pcregrep and
+pcretest programs here:
+
+  http://www.rexegg.com/pcregrep-pcretest.html
+
+
+Building PCRE on non-Unix-like systems
+--------------------------------------
+
+For a non-Unix-like system, please read the comments in the file
+NON-AUTOTOOLS-BUILD, though if your system supports the use of "configure" and
+"make" you may be able to build PCRE using autotools in the same way as for
+many Unix-like systems.
+
+PCRE can also be configured using the GUI facility provided by CMake's
+cmake-gui command. This creates Makefiles, solution files, etc. The file
+NON-AUTOTOOLS-BUILD has information about CMake.
+
+PCRE has been compiled on many different operating systems. It should be
+straightforward to build PCRE on any system that has a Standard C compiler and
+library, because it uses only Standard C functions.
+
+
+Building PCRE without using autotools
+-------------------------------------
+
+The use of autotools (in particular, libtool) is problematic in some
+environments, even some that are Unix or Unix-like. See the NON-AUTOTOOLS-BUILD
+file for ways of building PCRE without using autotools.
+
+
+Building PCRE using autotools
+-----------------------------
+
+If you are using HP's ANSI C++ compiler (aCC), please see the special note
+in the section entitled "Using HP's ANSI C++ compiler (aCC)" below.
+
+The following instructions assume the use of the widely used "configure; make;
+make install" (autotools) process.
+
+To build PCRE on system that supports autotools, first run the "configure"
+command from the PCRE distribution directory, with your current directory set
+to the directory where you want the files to be created. This command is a
+standard GNU "autoconf" configuration script, for which generic instructions
+are supplied in the file INSTALL.
+
+Most commonly, people build PCRE within its own distribution directory, and in
+this case, on many systems, just running "./configure" is sufficient. However,
+the usual methods of changing standard defaults are available. For example:
+
+CFLAGS='-O2 -Wall' ./configure --prefix=/opt/local
+
+This command specifies that the C compiler should be run with the flags '-O2
+-Wall' instead of the default, and that "make install" should install PCRE
+under /opt/local instead of the default /usr/local.
+
+If you want to build in a different directory, just run "configure" with that
+directory as current. For example, suppose you have unpacked the PCRE source
+into /source/pcre/pcre-xxx, but you want to build it in /build/pcre/pcre-xxx:
+
+cd /build/pcre/pcre-xxx
+/source/pcre/pcre-xxx/configure
+
+PCRE is written in C and is normally compiled as a C library. However, it is
+possible to build it as a C++ library, though the provided building apparatus
+does not have any features to support this.
+
+There are some optional features that can be included or omitted from the PCRE
+library. They are also documented in the pcrebuild man page.
+
+. By default, both shared and static libraries are built. You can change this
+  by adding one of these options to the "configure" command:
+
+  --disable-shared
+  --disable-static
+
+  (See also "Shared libraries on Unix-like systems" below.)
+
+. By default, only the 8-bit library is built. If you add --enable-pcre16 to
+  the "configure" command, the 16-bit library is also built. If you add
+  --enable-pcre32 to the "configure" command, the 32-bit library is also built.
+  If you want only the 16-bit or 32-bit library, use --disable-pcre8 to disable
+  building the 8-bit library.
+
+. If you are building the 8-bit library and want to suppress the building of
+  the C++ wrapper library, you can add --disable-cpp to the "configure"
+  command. Otherwise, when "configure" is run without --disable-pcre8, it will
+  try to find a C++ compiler and C++ header files, and if it succeeds, it will
+  try to build the C++ wrapper.
+
+. If you want to include support for just-in-time compiling, which can give
+  large performance improvements on certain platforms, add --enable-jit to the
+  "configure" command. This support is available only for certain hardware
+  architectures. If you try to enable it on an unsupported architecture, there
+  will be a compile time error.
+
+. When JIT support is enabled, pcregrep automatically makes use of it, unless
+  you add --disable-pcregrep-jit to the "configure" command.
+
+. If you want to make use of the support for UTF-8 Unicode character strings in
+  the 8-bit library, or UTF-16 Unicode character strings in the 16-bit library,
+  or UTF-32 Unicode character strings in the 32-bit library, you must add
+  --enable-utf to the "configure" command. Without it, the code for handling
+  UTF-8, UTF-16 and UTF-8 is not included in the relevant library. Even
+  when --enable-utf is included, the use of a UTF encoding still has to be
+  enabled by an option at run time. When PCRE is compiled with this option, its
+  input can only either be ASCII or UTF-8/16/32, even when running on EBCDIC
+  platforms. It is not possible to use both --enable-utf and --enable-ebcdic at
+  the same time.
+
+. There are no separate options for enabling UTF-8, UTF-16 and UTF-32
+  independently because that would allow ridiculous settings such as requesting
+  UTF-16 support while building only the 8-bit library. However, the option
+  --enable-utf8 is retained for backwards compatibility with earlier releases
+  that did not support 16-bit or 32-bit character strings. It is synonymous with
+  --enable-utf. It is not possible to configure one library with UTF support
+  and the other without in the same configuration.
+
+. If, in addition to support for UTF-8/16/32 character strings, you want to
+  include support for the \P, \p, and \X sequences that recognize Unicode
+  character properties, you must add --enable-unicode-properties to the
+  "configure" command. This adds about 30K to the size of the library (in the
+  form of a property table); only the basic two-letter properties such as Lu
+  are supported.
+
+. You can build PCRE to recognize either CR or LF or the sequence CRLF or any
+  of the preceding, or any of the Unicode newline sequences as indicating the
+  end of a line. Whatever you specify at build time is the default; the caller
+  of PCRE can change the selection at run time. The default newline indicator
+  is a single LF character (the Unix standard). You can specify the default
+  newline indicator by adding --enable-newline-is-cr or --enable-newline-is-lf
+  or --enable-newline-is-crlf or --enable-newline-is-anycrlf or
+  --enable-newline-is-any to the "configure" command, respectively.
+
+  If you specify --enable-newline-is-cr or --enable-newline-is-crlf, some of
+  the standard tests will fail, because the lines in the test files end with
+  LF. Even if the files are edited to change the line endings, there are likely
+  to be some failures. With --enable-newline-is-anycrlf or
+  --enable-newline-is-any, many tests should succeed, but there may be some
+  failures.
+
+. By default, the sequence \R in a pattern matches any Unicode line ending
+  sequence. This is independent of the option specifying what PCRE considers to
+  be the end of a line (see above). However, the caller of PCRE can restrict \R
+  to match only CR, LF, or CRLF. You can make this the default by adding
+  --enable-bsr-anycrlf to the "configure" command (bsr = "backslash R").
+
+. When called via the POSIX interface, PCRE uses malloc() to get additional
+  storage for processing capturing parentheses if there are more than 10 of
+  them in a pattern. You can increase this threshold by setting, for example,
+
+  --with-posix-malloc-threshold=20
+
+  on the "configure" command.
+
+. PCRE has a counter that limits the depth of nesting of parentheses in a
+  pattern. This limits the amount of system stack that a pattern uses when it
+  is compiled. The default is 250, but you can change it by setting, for
+  example,
+
+  --with-parens-nest-limit=500
+
+. PCRE has a counter that can be set to limit the amount of resources it uses
+  when matching a pattern. If the limit is exceeded during a match, the match
+  fails. The default is ten million. You can change the default by setting, for
+  example,
+
+  --with-match-limit=500000
+
+  on the "configure" command. This is just the default; individual calls to
+  pcre_exec() can supply their own value. There is more discussion on the
+  pcreapi man page.
+
+. There is a separate counter that limits the depth of recursive function calls
+  during a matching process. This also has a default of ten million, which is
+  essentially "unlimited". You can change the default by setting, for example,
+
+  --with-match-limit-recursion=500000
+
+  Recursive function calls use up the runtime stack; running out of stack can
+  cause programs to crash in strange ways. There is a discussion about stack
+  sizes in the pcrestack man page.
+
+. The default maximum compiled pattern size is around 64K. You can increase
+  this by adding --with-link-size=3 to the "configure" command. In the 8-bit
+  library, PCRE then uses three bytes instead of two for offsets to different
+  parts of the compiled pattern. In the 16-bit library, --with-link-size=3 is
+  the same as --with-link-size=4, which (in both libraries) uses four-byte
+  offsets. Increasing the internal link size reduces performance. In the 32-bit
+  library, the only supported link size is 4.
+
+. You can build PCRE so that its internal match() function that is called from
+  pcre_exec() does not call itself recursively. Instead, it uses memory blocks
+  obtained from the heap via the special functions pcre_stack_malloc() and
+  pcre_stack_free() to save data that would otherwise be saved on the stack. To
+  build PCRE like this, use
+
+  --disable-stack-for-recursion
+
+  on the "configure" command. PCRE runs more slowly in this mode, but it may be
+  necessary in environments with limited stack sizes. This applies only to the
+  normal execution of the pcre_exec() function; if JIT support is being
+  successfully used, it is not relevant. Equally, it does not apply to
+  pcre_dfa_exec(), which does not use deeply nested recursion. There is a
+  discussion about stack sizes in the pcrestack man page.
+
+. For speed, PCRE uses four tables for manipulating and identifying characters
+  whose code point values are less than 256. By default, it uses a set of
+  tables for ASCII encoding that is part of the distribution. If you specify
+
+  --enable-rebuild-chartables
+
+  a program called dftables is compiled and run in the default C locale when
+  you obey "make". It builds a source file called pcre_chartables.c. If you do
+  not specify this option, pcre_chartables.c is created as a copy of
+  pcre_chartables.c.dist. See "Character tables" below for further information.
+
+. It is possible to compile PCRE for use on systems that use EBCDIC as their
+  character code (as opposed to ASCII/Unicode) by specifying
+
+  --enable-ebcdic
+
+  This automatically implies --enable-rebuild-chartables (see above). However,
+  when PCRE is built this way, it always operates in EBCDIC. It cannot support
+  both EBCDIC and UTF-8/16/32. There is a second option, --enable-ebcdic-nl25,
+  which specifies that the code value for the EBCDIC NL character is 0x25
+  instead of the default 0x15.
+
+. In environments where valgrind is installed, if you specify
+
+  --enable-valgrind
+
+  PCRE will use valgrind annotations to mark certain memory regions as
+  unaddressable. This allows it to detect invalid memory accesses, and is
+  mostly useful for debugging PCRE itself.
+
+. In environments where the gcc compiler is used and lcov version 1.6 or above
+  is installed, if you specify
+
+  --enable-coverage
+
+  the build process implements a code coverage report for the test suite. The
+  report is generated by running "make coverage". If ccache is installed on
+  your system, it must be disabled when building PCRE for coverage reporting.
+  You can do this by setting the environment variable CCACHE_DISABLE=1 before
+  running "make" to build PCRE. There is more information about coverage
+  reporting in the "pcrebuild" documentation.
+
+. The pcregrep program currently supports only 8-bit data files, and so
+  requires the 8-bit PCRE library. It is possible to compile pcregrep to use
+  libz and/or libbz2, in order to read .gz and .bz2 files (respectively), by
+  specifying one or both of
+
+  --enable-pcregrep-libz
+  --enable-pcregrep-libbz2
+
+  Of course, the relevant libraries must be installed on your system.
+
+. The default size (in bytes) of the internal buffer used by pcregrep can be
+  set by, for example:
+
+  --with-pcregrep-bufsize=51200
+
+  The value must be a plain integer. The default is 20480.
+
+. It is possible to compile pcretest so that it links with the libreadline
+  or libedit libraries, by specifying, respectively,
+
+  --enable-pcretest-libreadline or --enable-pcretest-libedit
+
+  If this is done, when pcretest's input is from a terminal, it reads it using
+  the readline() function. This provides line-editing and history facilities.
+  Note that libreadline is GPL-licenced, so if you distribute a binary of
+  pcretest linked in this way, there may be licensing issues. These can be
+  avoided by linking with libedit (which has a BSD licence) instead.
+
+  Enabling libreadline causes the -lreadline option to be added to the pcretest
+  build. In many operating environments with a sytem-installed readline
+  library this is sufficient. However, in some environments (e.g. if an
+  unmodified distribution version of readline is in use), it may be necessary
+  to specify something like LIBS="-lncurses" as well. This is because, to quote
+  the readline INSTALL, "Readline uses the termcap functions, but does not link
+  with the termcap or curses library itself, allowing applications which link
+  with readline the to choose an appropriate library." If you get error
+  messages about missing functions tgetstr, tgetent, tputs, tgetflag, or tgoto,
+  this is the problem, and linking with the ncurses library should fix it.
+
+The "configure" script builds the following files for the basic C library:
+
+. Makefile             the makefile that builds the library
+. config.h             build-time configuration options for the library
+. pcre.h               the public PCRE header file
+. pcre-config          script that shows the building settings such as CFLAGS
+                         that were set for "configure"
+. libpcre.pc         ) data for the pkg-config command
+. libpcre16.pc       )
+. libpcre32.pc       )
+. libpcreposix.pc    )
+. libtool              script that builds shared and/or static libraries
+
+Versions of config.h and pcre.h are distributed in the PCRE tarballs under the
+names config.h.generic and pcre.h.generic. These are provided for those who
+have to built PCRE without using "configure" or CMake. If you use "configure"
+or CMake, the .generic versions are not used.
+
+When building the 8-bit library, if a C++ compiler is found, the following
+files are also built:
+
+. libpcrecpp.pc        data for the pkg-config command
+. pcrecpparg.h         header file for calling PCRE via the C++ wrapper
+. pcre_stringpiece.h   header for the C++ "stringpiece" functions
+
+The "configure" script also creates config.status, which is an executable
+script that can be run to recreate the configuration, and config.log, which
+contains compiler output from tests that "configure" runs.
+
+Once "configure" has run, you can run "make". This builds the the libraries
+libpcre, libpcre16 and/or libpcre32, and a test program called pcretest. If you
+enabled JIT support with --enable-jit, a test program called pcre_jit_test is
+built as well.
+
+If the 8-bit library is built, libpcreposix and the pcregrep command are also
+built, and if a C++ compiler was found on your system, and you did not disable
+it with --disable-cpp, "make" builds the C++ wrapper library, which is called
+libpcrecpp, as well as some test programs called pcrecpp_unittest,
+pcre_scanner_unittest, and pcre_stringpiece_unittest.
+
+The command "make check" runs all the appropriate tests. Details of the PCRE
+tests are given below in a separate section of this document.
+
+You can use "make install" to install PCRE into live directories on your
+system. The following are installed (file names are all relative to the
+<prefix> that is set when "configure" is run):
+
+  Commands (bin):
+    pcretest
+    pcregrep (if 8-bit support is enabled)
+    pcre-config
+
+  Libraries (lib):
+    libpcre16     (if 16-bit support is enabled)
+    libpcre32     (if 32-bit support is enabled)
+    libpcre       (if 8-bit support is enabled)
+    libpcreposix  (if 8-bit support is enabled)
+    libpcrecpp    (if 8-bit and C++ support is enabled)
+
+  Configuration information (lib/pkgconfig):
+    libpcre16.pc
+    libpcre32.pc
+    libpcre.pc
+    libpcreposix.pc
+    libpcrecpp.pc (if C++ support is enabled)
+
+  Header files (include):
+    pcre.h
+    pcreposix.h
+    pcre_scanner.h      )
+    pcre_stringpiece.h  ) if C++ support is enabled
+    pcrecpp.h           )
+    pcrecpparg.h        )
+
+  Man pages (share/man/man{1,3}):
+    pcregrep.1
+    pcretest.1
+    pcre-config.1
+    pcre.3
+    pcre*.3 (lots more pages, all starting "pcre")
+
+  HTML documentation (share/doc/pcre/html):
+    index.html
+    *.html (lots more pages, hyperlinked from index.html)
+
+  Text file documentation (share/doc/pcre):
+    AUTHORS
+    COPYING
+    ChangeLog
+    LICENCE
+    NEWS
+    README
+    pcre.txt         (a concatenation of the man(3) pages)
+    pcretest.txt     the pcretest man page
+    pcregrep.txt     the pcregrep man page
+    pcre-config.txt  the pcre-config man page
+
+If you want to remove PCRE from your system, you can run "make uninstall".
+This removes all the files that "make install" installed. However, it does not
+remove any directories, because these are often shared with other programs.
+
+
+Retrieving configuration information
+------------------------------------
+
+Running "make install" installs the command pcre-config, which can be used to
+recall information about the PCRE configuration and installation. For example:
+
+  pcre-config --version
+
+prints the version number, and
+
+  pcre-config --libs
+
+outputs information about where the library is installed. This command can be
+included in makefiles for programs that use PCRE, saving the programmer from
+having to remember too many details.
+
+The pkg-config command is another system for saving and retrieving information
+about installed libraries. Instead of separate commands for each library, a
+single command is used. For example:
+
+  pkg-config --cflags pcre
+
+The data is held in *.pc files that are installed in a directory called
+<prefix>/lib/pkgconfig.
+
+
+Shared libraries
+----------------
+
+The default distribution builds PCRE as shared libraries and static libraries,
+as long as the operating system supports shared libraries. Shared library
+support relies on the "libtool" script which is built as part of the
+"configure" process.
+
+The libtool script is used to compile and link both shared and static
+libraries. They are placed in a subdirectory called .libs when they are newly
+built. The programs pcretest and pcregrep are built to use these uninstalled
+libraries (by means of wrapper scripts in the case of shared libraries). When
+you use "make install" to install shared libraries, pcregrep and pcretest are
+automatically re-built to use the newly installed shared libraries before being
+installed themselves. However, the versions left in the build directory still
+use the uninstalled libraries.
+
+To build PCRE using static libraries only you must use --disable-shared when
+configuring it. For example:
+
+./configure --prefix=/usr/gnu --disable-shared
+
+Then run "make" in the usual way. Similarly, you can use --disable-static to
+build only shared libraries.
+
+
+Cross-compiling using autotools
+-------------------------------
+
+You can specify CC and CFLAGS in the normal way to the "configure" command, in
+order to cross-compile PCRE for some other host. However, you should NOT
+specify --enable-rebuild-chartables, because if you do, the dftables.c source
+file is compiled and run on the local host, in order to generate the inbuilt
+character tables (the pcre_chartables.c file). This will probably not work,
+because dftables.c needs to be compiled with the local compiler, not the cross
+compiler.
+
+When --enable-rebuild-chartables is not specified, pcre_chartables.c is created
+by making a copy of pcre_chartables.c.dist, which is a default set of tables
+that assumes ASCII code. Cross-compiling with the default tables should not be
+a problem.
+
+If you need to modify the character tables when cross-compiling, you should
+move pcre_chartables.c.dist out of the way, then compile dftables.c by hand and
+run it on the local host to make a new version of pcre_chartables.c.dist.
+Then when you cross-compile PCRE this new version of the tables will be used.
+
+
+Using HP's ANSI C++ compiler (aCC)
+----------------------------------
+
+Unless C++ support is disabled by specifying the "--disable-cpp" option of the
+"configure" script, you must include the "-AA" option in the CXXFLAGS
+environment variable in order for the C++ components to compile correctly.
+
+Also, note that the aCC compiler on PA-RISC platforms may have a defect whereby
+needed libraries fail to get included when specifying the "-AA" compiler
+option. If you experience unresolved symbols when linking the C++ programs,
+use the workaround of specifying the following environment variable prior to
+running the "configure" script:
+
+  CXXLDFLAGS="-lstd_v2 -lCsup_v2"
+
+
+Compiling in Tru64 using native compilers
+-----------------------------------------
+
+The following error may occur when compiling with native compilers in the Tru64
+operating system:
+
+  CXX    libpcrecpp_la-pcrecpp.lo
+cxx: Error: /usr/lib/cmplrs/cxx/V7.1-006/include/cxx/iosfwd, line 58: #error
+          directive: "cannot include iosfwd -- define __USE_STD_IOSTREAM to
+          override default - see section 7.1.2 of the C++ Using Guide"
+#error "cannot include iosfwd -- define __USE_STD_IOSTREAM to override default
+- see section 7.1.2 of the C++ Using Guide"
+
+This may be followed by other errors, complaining that 'namespace "std" has no
+member'. The solution to this is to add the line
+
+#define __USE_STD_IOSTREAM 1
+
+to the config.h file.
+
+
+Using Sun's compilers for Solaris
+---------------------------------
+
+A user reports that the following configurations work on Solaris 9 sparcv9 and
+Solaris 9 x86 (32-bit):
+
+  Solaris 9 sparcv9: ./configure --disable-cpp CC=/bin/cc CFLAGS="-m64 -g"
+  Solaris 9 x86:     ./configure --disable-cpp CC=/bin/cc CFLAGS="-g"
+
+
+Using PCRE from MySQL
+---------------------
+
+On systems where both PCRE and MySQL are installed, it is possible to make use
+of PCRE from within MySQL, as an alternative to the built-in pattern matching.
+There is a web page that tells you how to do this:
+
+  http://www.mysqludf.org/lib_mysqludf_preg/index.php
+
+
+Making new tarballs
+-------------------
+
+The command "make dist" creates three PCRE tarballs, in tar.gz, tar.bz2, and
+zip formats. The command "make distcheck" does the same, but then does a trial
+build of the new distribution to ensure that it works.
+
+If you have modified any of the man page sources in the doc directory, you
+should first run the PrepareRelease script before making a distribution. This
+script creates the .txt and HTML forms of the documentation from the man pages.
+
+
+Testing PCRE
+------------
+
+To test the basic PCRE library on a Unix-like system, run the RunTest script.
+There is another script called RunGrepTest that tests the options of the
+pcregrep command. If the C++ wrapper library is built, three test programs
+called pcrecpp_unittest, pcre_scanner_unittest, and pcre_stringpiece_unittest
+are also built. When JIT support is enabled, another test program called
+pcre_jit_test is built.
+
+Both the scripts and all the program tests are run if you obey "make check" or
+"make test". For other environments, see the instructions in
+NON-AUTOTOOLS-BUILD.
+
+The RunTest script runs the pcretest test program (which is documented in its
+own man page) on each of the relevant testinput files in the testdata
+directory, and compares the output with the contents of the corresponding
+testoutput files. RunTest uses a file called testtry to hold the main output
+from pcretest. Other files whose names begin with "test" are used as working
+files in some tests.
+
+Some tests are relevant only when certain build-time options were selected. For
+example, the tests for UTF-8/16/32 support are run only if --enable-utf was
+used. RunTest outputs a comment when it skips a test.
+
+Many of the tests that are not skipped are run up to three times. The second
+run forces pcre_study() to be called for all patterns except for a few in some
+tests that are marked "never study" (see the pcretest program for how this is
+done). If JIT support is available, the non-DFA tests are run a third time,
+this time with a forced pcre_study() with the PCRE_STUDY_JIT_COMPILE option.
+This testing can be suppressed by putting "nojit" on the RunTest command line.
+
+The entire set of tests is run once for each of the 8-bit, 16-bit and 32-bit
+libraries that are enabled. If you want to run just one set of tests, call
+RunTest with either the -8, -16 or -32 option.
+
+If valgrind is installed, you can run the tests under it by putting "valgrind"
+on the RunTest command line. To run pcretest on just one or more specific test
+files, give their numbers as arguments to RunTest, for example:
+
+  RunTest 2 7 11
+
+You can also specify ranges of tests such as 3-6 or 3- (meaning 3 to the
+end), or a number preceded by ~ to exclude a test. For example:
+
+  Runtest 3-15 ~10
+
+This runs tests 3 to 15, excluding test 10, and just ~13 runs all the tests
+except test 13. Whatever order the arguments are in, the tests are always run
+in numerical order.
+
+You can also call RunTest with the single argument "list" to cause it to output
+a list of tests.
+
+The first test file can be fed directly into the perltest.pl script to check
+that Perl gives the same results. The only difference you should see is in the
+first few lines, where the Perl version is given instead of the PCRE version.
+
+The second set of tests check pcre_fullinfo(), pcre_study(),
+pcre_copy_substring(), pcre_get_substring(), pcre_get_substring_list(), error
+detection, and run-time flags that are specific to PCRE, as well as the POSIX
+wrapper API. It also uses the debugging flags to check some of the internals of
+pcre_compile().
+
+If you build PCRE with a locale setting that is not the standard C locale, the
+character tables may be different (see next paragraph). In some cases, this may
+cause failures in the second set of tests. For example, in a locale where the
+isprint() function yields TRUE for characters in the range 128-255, the use of
+[:isascii:] inside a character class defines a different set of characters, and
+this shows up in this test as a difference in the compiled code, which is being
+listed for checking. Where the comparison test output contains [\x00-\x7f] the
+test will contain [\x00-\xff], and similarly in some other cases. This is not a
+bug in PCRE.
+
+The third set of tests checks pcre_maketables(), the facility for building a
+set of character tables for a specific locale and using them instead of the
+default tables. The tests make use of the "fr_FR" (French) locale. Before
+running the test, the script checks for the presence of this locale by running
+the "locale" command. If that command fails, or if it doesn't include "fr_FR"
+in the list of available locales, the third test cannot be run, and a comment
+is output to say why. If running this test produces instances of the error
+
+  ** Failed to set locale "fr_FR"
+
+in the comparison output, it means that locale is not available on your system,
+despite being listed by "locale". This does not mean that PCRE is broken.
+
+[If you are trying to run this test on Windows, you may be able to get it to
+work by changing "fr_FR" to "french" everywhere it occurs. Alternatively, use
+RunTest.bat. The version of RunTest.bat included with PCRE 7.4 and above uses
+Windows versions of test 2. More info on using RunTest.bat is included in the
+document entitled NON-UNIX-USE.]
+
+The fourth and fifth tests check the UTF-8/16/32 support and error handling and
+internal UTF features of PCRE that are not relevant to Perl, respectively. The
+sixth and seventh tests do the same for Unicode character properties support.
+
+The eighth, ninth, and tenth tests check the pcre_dfa_exec() alternative
+matching function, in non-UTF-8/16/32 mode, UTF-8/16/32 mode, and UTF-8/16/32
+mode with Unicode property support, respectively.
+
+The eleventh test checks some internal offsets and code size features; it is
+run only when the default "link size" of 2 is set (in other cases the sizes
+change) and when Unicode property support is enabled.
+
+The twelfth test is run only when JIT support is available, and the thirteenth
+test is run only when JIT support is not available. They test some JIT-specific
+features such as information output from pcretest about JIT compilation.
+
+The fourteenth, fifteenth, and sixteenth tests are run only in 8-bit mode, and
+the seventeenth, eighteenth, and nineteenth tests are run only in 16/32-bit
+mode. These are tests that generate different output in the two modes. They are
+for general cases, UTF-8/16/32 support, and Unicode property support,
+respectively.
+
+The twentieth test is run only in 16/32-bit mode. It tests some specific
+16/32-bit features of the DFA matching engine.
+
+The twenty-first and twenty-second tests are run only in 16/32-bit mode, when
+the link size is set to 2 for the 16-bit library. They test reloading
+pre-compiled patterns.
+
+The twenty-third and twenty-fourth tests are run only in 16-bit mode. They are
+for general cases, and UTF-16 support, respectively.
+
+The twenty-fifth and twenty-sixth tests are run only in 32-bit mode. They are
+for general cases, and UTF-32 support, respectively.
+
+
+Character tables
+----------------
+
+For speed, PCRE uses four tables for manipulating and identifying characters
+whose code point values are less than 256. The final argument of the
+pcre_compile() function is a pointer to a block of memory containing the
+concatenated tables. A call to pcre_maketables() can be used to generate a set
+of tables in the current locale. If the final argument for pcre_compile() is
+passed as NULL, a set of default tables that is built into the binary is used.
+
+The source file called pcre_chartables.c contains the default set of tables. By
+default, this is created as a copy of pcre_chartables.c.dist, which contains
+tables for ASCII coding. However, if --enable-rebuild-chartables is specified
+for ./configure, a different version of pcre_chartables.c is built by the
+program dftables (compiled from dftables.c), which uses the ANSI C character
+handling functions such as isalnum(), isalpha(), isupper(), islower(), etc. to
+build the table sources. This means that the default C locale which is set for
+your system will control the contents of these default tables. You can change
+the default tables by editing pcre_chartables.c and then re-building PCRE. If
+you do this, you should take care to ensure that the file does not get
+automatically re-generated. The best way to do this is to move
+pcre_chartables.c.dist out of the way and replace it with your customized
+tables.
+
+When the dftables program is run as a result of --enable-rebuild-chartables,
+it uses the default C locale that is set on your system. It does not pay
+attention to the LC_xxx environment variables. In other words, it uses the
+system's default locale rather than whatever the compiling user happens to have
+set. If you really do want to build a source set of character tables in a
+locale that is specified by the LC_xxx variables, you can run the dftables
+program by hand with the -L option. For example:
+
+  ./dftables -L pcre_chartables.c.special
+
+The first two 256-byte tables provide lower casing and case flipping functions,
+respectively. The next table consists of three 32-byte bit maps which identify
+digits, "word" characters, and white space, respectively. These are used when
+building 32-byte bit maps that represent character classes for code points less
+than 256.
+
+The final 256-byte table has bits indicating various character types, as
+follows:
+
+    1   white space character
+    2   letter
+    4   decimal digit
+    8   hexadecimal digit
+   16   alphanumeric or '_'
+  128   regular expression metacharacter or binary zero
+
+You should not alter the set of characters that contain the 128 bit, as that
+will cause PCRE to malfunction.
+
+
+File manifest
+-------------
+
+The distribution should contain the files listed below. Where a file name is
+given as pcre[16|32]_xxx it means that there are three files, one with the name
+pcre_xxx, one with the name pcre16_xx, and a third with the name pcre32_xxx.
+
+(A) Source files of the PCRE library functions and their headers:
+
+  dftables.c              auxiliary program for building pcre_chartables.c
+                          when --enable-rebuild-chartables is specified
+
+  pcre_chartables.c.dist  a default set of character tables that assume ASCII
+                          coding; used, unless --enable-rebuild-chartables is
+                          specified, by copying to pcre[16]_chartables.c
+
+  pcreposix.c                )
+  pcre[16|32]_byte_order.c   )
+  pcre[16|32]_compile.c      )
+  pcre[16|32]_config.c       )
+  pcre[16|32]_dfa_exec.c     )
+  pcre[16|32]_exec.c         )
+  pcre[16|32]_fullinfo.c     )
+  pcre[16|32]_get.c          ) sources for the functions in the library,
+  pcre[16|32]_globals.c      )   and some internal functions that they use
+  pcre[16|32]_jit_compile.c  )
+  pcre[16|32]_maketables.c   )
+  pcre[16|32]_newline.c      )
+  pcre[16|32]_refcount.c     )
+  pcre[16|32]_string_utils.c )
+  pcre[16|32]_study.c        )
+  pcre[16|32]_tables.c       )
+  pcre[16|32]_ucd.c          )
+  pcre[16|32]_version.c      )
+  pcre[16|32]_xclass.c       )
+  pcre_ord2utf8.c            )
+  pcre_valid_utf8.c          )
+  pcre16_ord2utf16.c         )
+  pcre16_utf16_utils.c       )
+  pcre16_valid_utf16.c       )
+  pcre32_utf32_utils.c       )
+  pcre32_valid_utf32.c       )
+
+  pcre[16|32]_printint.c     ) debugging function that is used by pcretest,
+                             )   and can also be #included in pcre_compile()
+
+  pcre.h.in               template for pcre.h when built by "configure"
+  pcreposix.h             header for the external POSIX wrapper API
+  pcre_internal.h         header for internal use
+  sljit/*                 16 files that make up the JIT compiler
+  ucp.h                   header for Unicode property handling
+
+  config.h.in             template for config.h, which is built by "configure"
+
+  pcrecpp.h               public header file for the C++ wrapper
+  pcrecpparg.h.in         template for another C++ header file
+  pcre_scanner.h          public header file for C++ scanner functions
+  pcrecpp.cc              )
+  pcre_scanner.cc         ) source for the C++ wrapper library
+
+  pcre_stringpiece.h.in   template for pcre_stringpiece.h, the header for the
+                            C++ stringpiece functions
+  pcre_stringpiece.cc     source for the C++ stringpiece functions
+
+(B) Source files for programs that use PCRE:
+
+  pcredemo.c              simple demonstration of coding calls to PCRE
+  pcregrep.c              source of a grep utility that uses PCRE
+  pcretest.c              comprehensive test program
+
+(C) Auxiliary files:
+
+  132html                 script to turn "man" pages into HTML
+  AUTHORS                 information about the author of PCRE
+  ChangeLog               log of changes to the code
+  CleanTxt                script to clean nroff output for txt man pages
+  Detrail                 script to remove trailing spaces
+  HACKING                 some notes about the internals of PCRE
+  INSTALL                 generic installation instructions
+  LICENCE                 conditions for the use of PCRE
+  COPYING                 the same, using GNU's standard name
+  Makefile.in             ) template for Unix Makefile, which is built by
+                          )   "configure"
+  Makefile.am             ) the automake input that was used to create
+                          )   Makefile.in
+  NEWS                    important changes in this release
+  NON-UNIX-USE            the previous name for NON-AUTOTOOLS-BUILD
+  NON-AUTOTOOLS-BUILD     notes on building PCRE without using autotools
+  PrepareRelease          script to make preparations for "make dist"
+  README                  this file
+  RunTest                 a Unix shell script for running tests
+  RunGrepTest             a Unix shell script for pcregrep tests
+  aclocal.m4              m4 macros (generated by "aclocal")
+  config.guess            ) files used by libtool,
+  config.sub              )   used only when building a shared library
+  configure               a configuring shell script (built by autoconf)
+  configure.ac            ) the autoconf input that was used to build
+                          )   "configure" and config.h
+  depcomp                 ) script to find program dependencies, generated by
+                          )   automake
+  doc/*.3                 man page sources for PCRE
+  doc/*.1                 man page sources for pcregrep and pcretest
+  doc/index.html.src      the base HTML page
+  doc/html/*              HTML documentation
+  doc/pcre.txt            plain text version of the man pages
+  doc/pcretest.txt        plain text documentation of test program
+  doc/perltest.txt        plain text documentation of Perl test program
+  install-sh              a shell script for installing files
+  libpcre16.pc.in         template for libpcre16.pc for pkg-config
+  libpcre32.pc.in         template for libpcre32.pc for pkg-config
+  libpcre.pc.in           template for libpcre.pc for pkg-config
+  libpcreposix.pc.in      template for libpcreposix.pc for pkg-config
+  libpcrecpp.pc.in        template for libpcrecpp.pc for pkg-config
+  ltmain.sh               file used to build a libtool script
+  missing                 ) common stub for a few missing GNU programs while
+                          )   installing, generated by automake
+  mkinstalldirs           script for making install directories
+  perltest.pl             Perl test program
+  pcre-config.in          source of script which retains PCRE information
+  pcre_jit_test.c         test program for the JIT compiler
+  pcrecpp_unittest.cc          )
+  pcre_scanner_unittest.cc     ) test programs for the C++ wrapper
+  pcre_stringpiece_unittest.cc )
+  testdata/testinput*     test data for main library tests
+  testdata/testoutput*    expected test results
+  testdata/grep*          input and output for pcregrep tests
+  testdata/*              other supporting test files
+
+(D) Auxiliary files for cmake support
+
+  cmake/COPYING-CMAKE-SCRIPTS
+  cmake/FindPackageHandleStandardArgs.cmake
+  cmake/FindEditline.cmake
+  cmake/FindReadline.cmake
+  CMakeLists.txt
+  config-cmake.h.in
+
+(E) Auxiliary files for VPASCAL
+
+  makevp.bat
+  makevp_c.txt
+  makevp_l.txt
+  pcregexp.pas
+
+(F) Auxiliary files for building PCRE "by hand"
+
+  pcre.h.generic          ) a version of the public PCRE header file
+                          )   for use in non-"configure" environments
+  config.h.generic        ) a version of config.h for use in non-"configure"
+                          )   environments
+
+(F) Miscellaneous
+
+  RunTest.bat            a script for running tests under Windows
+
+Philip Hazel
+Email local part: ph10
+Email domain: cam.ac.uk
+Last updated: 17 January 2014
diff --git a/libs/Pcre16/docs/doc/html/index.html b/libs/Pcre16/docs/doc/html/index.html
new file mode 100644
index 0000000000..352c55df2f
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/index.html
@@ -0,0 +1,185 @@
+<html>
+<!-- This is a manually maintained file that is the root of the HTML version of
+     the PCRE documentation. When the HTML documents are built from the man
+     page versions, the entire doc/html directory is emptied, this file is then
+     copied into doc/html/index.html, and the remaining files therein are
+     created by the 132html script.
+-->
+<head>
+<title>PCRE specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>Perl-compatible Regular Expressions (PCRE)</h1>
+<p>
+The HTML documentation for PCRE consists of a number of pages that are listed
+below in alphabetical order. If you are new to PCRE, please read the first one
+first.
+</p>
+
+<table>
+<tr><td><a href="pcre.html">pcre</a></td>
+    <td>&nbsp;&nbsp;Introductory page</td></tr>
+
+<tr><td><a href="pcre-config.html">pcre-config</a></td>
+    <td>&nbsp;&nbsp;Information about the installation configuration</td></tr>
+
+<tr><td><a href="pcre16.html">pcre16</a></td>
+    <td>&nbsp;&nbsp;Discussion of the 16-bit PCRE library</td></tr>
+
+<tr><td><a href="pcre32.html">pcre32</a></td>
+    <td>&nbsp;&nbsp;Discussion of the 32-bit PCRE library</td></tr>
+
+<tr><td><a href="pcreapi.html">pcreapi</a></td>
+    <td>&nbsp;&nbsp;PCRE's native API</td></tr>
+
+<tr><td><a href="pcrebuild.html">pcrebuild</a></td>
+    <td>&nbsp;&nbsp;Building PCRE</td></tr>
+
+<tr><td><a href="pcrecallout.html">pcrecallout</a></td>
+    <td>&nbsp;&nbsp;The <i>callout</i> facility</td></tr>
+
+<tr><td><a href="pcrecompat.html">pcrecompat</a></td>
+    <td>&nbsp;&nbsp;Compability with Perl</td></tr>
+
+<tr><td><a href="pcrecpp.html">pcrecpp</a></td>
+    <td>&nbsp;&nbsp;The C++ wrapper for the PCRE library</td></tr>
+
+<tr><td><a href="pcredemo.html">pcredemo</a></td>
+    <td>&nbsp;&nbsp;A demonstration C program that uses the PCRE library</td></tr>
+
+<tr><td><a href="pcregrep.html">pcregrep</a></td>
+    <td>&nbsp;&nbsp;The <b>pcregrep</b> command</td></tr>
+
+<tr><td><a href="pcrejit.html">pcrejit</a></td>
+    <td>&nbsp;&nbsp;Discussion of the just-in-time optimization support</td></tr>
+
+<tr><td><a href="pcrelimits.html">pcrelimits</a></td>
+    <td>&nbsp;&nbsp;Details of size and other limits</td></tr>
+
+<tr><td><a href="pcrematching.html">pcrematching</a></td>
+    <td>&nbsp;&nbsp;Discussion of the two matching algorithms</td></tr>
+
+<tr><td><a href="pcrepartial.html">pcrepartial</a></td>
+    <td>&nbsp;&nbsp;Using PCRE for partial matching</td></tr>
+
+<tr><td><a href="pcrepattern.html">pcrepattern</a></td>
+    <td>&nbsp;&nbsp;Specification of the regular expressions supported by PCRE</td></tr>
+
+<tr><td><a href="pcreperform.html">pcreperform</a></td>
+    <td>&nbsp;&nbsp;Some comments on performance</td></tr>
+
+<tr><td><a href="pcreposix.html">pcreposix</a></td>
+    <td>&nbsp;&nbsp;The POSIX API to the PCRE 8-bit library</td></tr>
+
+<tr><td><a href="pcreprecompile.html">pcreprecompile</a></td>
+    <td>&nbsp;&nbsp;How to save and re-use compiled patterns</td></tr>
+
+<tr><td><a href="pcresample.html">pcresample</a></td>
+    <td>&nbsp;&nbsp;Discussion of the pcredemo program</td></tr>
+
+<tr><td><a href="pcrestack.html">pcrestack</a></td>
+    <td>&nbsp;&nbsp;Discussion of PCRE's stack usage</td></tr>
+
+<tr><td><a href="pcresyntax.html">pcresyntax</a></td>
+    <td>&nbsp;&nbsp;Syntax quick-reference summary</td></tr>
+
+<tr><td><a href="pcretest.html">pcretest</a></td>
+    <td>&nbsp;&nbsp;The <b>pcretest</b> command for testing PCRE</td></tr>
+
+<tr><td><a href="pcreunicode.html">pcreunicode</a></td>
+    <td>&nbsp;&nbsp;Discussion of Unicode and UTF-8/UTF-16/UTF-32 support</td></tr>
+</table>
+
+<p>
+There are also individual pages that summarize the interface for each function
+in the library. There is a single page for each triple of 8-bit/16-bit/32-bit
+functions.
+</p>
+
+<table>
+
+<tr><td><a href="pcre_assign_jit_stack.html">pcre_assign_jit_stack</a></td>
+    <td>&nbsp;&nbsp;Assign stack for JIT matching</td></tr>
+
+<tr><td><a href="pcre_compile.html">pcre_compile</a></td>
+    <td>&nbsp;&nbsp;Compile a regular expression</td></tr>
+
+<tr><td><a href="pcre_compile2.html">pcre_compile2</a></td>
+    <td>&nbsp;&nbsp;Compile a regular expression (alternate interface)</td></tr>
+
+<tr><td><a href="pcre_config.html">pcre_config</a></td>
+    <td>&nbsp;&nbsp;Show build-time configuration options</td></tr>
+
+<tr><td><a href="pcre_copy_named_substring.html">pcre_copy_named_substring</a></td>
+    <td>&nbsp;&nbsp;Extract named substring into given buffer</td></tr>
+
+<tr><td><a href="pcre_copy_substring.html">pcre_copy_substring</a></td>
+    <td>&nbsp;&nbsp;Extract numbered substring into given buffer</td></tr>
+
+<tr><td><a href="pcre_dfa_exec.html">pcre_dfa_exec</a></td>
+    <td>&nbsp;&nbsp;Match a compiled pattern to a subject string
+    (DFA algorithm; <i>not</i> Perl compatible)</td></tr>
+
+<tr><td><a href="pcre_exec.html">pcre_exec</a></td>
+    <td>&nbsp;&nbsp;Match a compiled pattern to a subject string
+    (Perl compatible)</td></tr>
+
+<tr><td><a href="pcre_free_study.html">pcre_free_study</a></td>
+    <td>&nbsp;&nbsp;Free study data</td></tr>
+
+<tr><td><a href="pcre_free_substring.html">pcre_free_substring</a></td>
+    <td>&nbsp;&nbsp;Free extracted substring</td></tr>
+
+<tr><td><a href="pcre_free_substring_list.html">pcre_free_substring_list</a></td>
+    <td>&nbsp;&nbsp;Free list of extracted substrings</td></tr>
+
+<tr><td><a href="pcre_fullinfo.html">pcre_fullinfo</a></td>
+    <td>&nbsp;&nbsp;Extract information about a pattern</td></tr>
+
+<tr><td><a href="pcre_get_named_substring.html">pcre_get_named_substring</a></td>
+    <td>&nbsp;&nbsp;Extract named substring into new memory</td></tr>
+
+<tr><td><a href="pcre_get_stringnumber.html">pcre_get_stringnumber</a></td>
+    <td>&nbsp;&nbsp;Convert captured string name to number</td></tr>
+
+<tr><td><a href="pcre_get_stringtable_entries.html">pcre_get_stringtable_entries</a></td>
+    <td>&nbsp;&nbsp;Find table entries for given string name</td></tr>
+
+<tr><td><a href="pcre_get_substring.html">pcre_get_substring</a></td>
+    <td>&nbsp;&nbsp;Extract numbered substring into new memory</td></tr>
+
+<tr><td><a href="pcre_get_substring_list.html">pcre_get_substring_list</a></td>
+    <td>&nbsp;&nbsp;Extract all substrings into new memory</td></tr>
+
+<tr><td><a href="pcre_jit_exec.html">pcre_jit_exec</a></td>
+    <td>&nbsp;&nbsp;Fast path interface to JIT matching</td></tr>
+
+<tr><td><a href="pcre_jit_stack_alloc.html">pcre_jit_stack_alloc</a></td>
+    <td>&nbsp;&nbsp;Create a stack for JIT matching</td></tr>
+
+<tr><td><a href="pcre_jit_stack_free.html">pcre_jit_stack_free</a></td>
+    <td>&nbsp;&nbsp;Free a JIT matching stack</td></tr>
+
+<tr><td><a href="pcre_maketables.html">pcre_maketables</a></td>
+    <td>&nbsp;&nbsp;Build character tables in current locale</td></tr>
+
+<tr><td><a href="pcre_pattern_to_host_byte_order.html">pcre_pattern_to_host_byte_order</a></td>
+    <td>&nbsp;&nbsp;Convert compiled pattern to host byte order if necessary</td></tr>
+
+<tr><td><a href="pcre_refcount.html">pcre_refcount</a></td>
+    <td>&nbsp;&nbsp;Maintain reference count in compiled pattern</td></tr>
+
+<tr><td><a href="pcre_study.html">pcre_study</a></td>
+    <td>&nbsp;&nbsp;Study a compiled pattern</td></tr>
+
+<tr><td><a href="pcre_utf16_to_host_byte_order.html">pcre_utf16_to_host_byte_order</a></td>
+    <td>&nbsp;&nbsp;Convert UTF-16 string to host byte order if necessary</td></tr>
+
+<tr><td><a href="pcre_utf32_to_host_byte_order.html">pcre_utf32_to_host_byte_order</a></td>
+    <td>&nbsp;&nbsp;Convert UTF-32 string to host byte order if necessary</td></tr>
+
+<tr><td><a href="pcre_version.html">pcre_version</a></td>
+    <td>&nbsp;&nbsp;Return PCRE version and release date</td></tr>
+</table>
+
+</html>
diff --git a/libs/Pcre16/docs/doc/html/pcre-config.html b/libs/Pcre16/docs/doc/html/pcre-config.html
new file mode 100644
index 0000000000..56a8060492
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcre-config.html
@@ -0,0 +1,109 @@
+<html>
+<head>
+<title>pcre-config specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcre-config man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<ul>
+<li><a name="TOC1" href="#SEC1">SYNOPSIS</a>
+<li><a name="TOC2" href="#SEC2">DESCRIPTION</a>
+<li><a name="TOC3" href="#SEC3">OPTIONS</a>
+<li><a name="TOC4" href="#SEC4">SEE ALSO</a>
+<li><a name="TOC5" href="#SEC5">AUTHOR</a>
+<li><a name="TOC6" href="#SEC6">REVISION</a>
+</ul>
+<br><a name="SEC1" href="#TOC1">SYNOPSIS</a><br>
+<P>
+<b>pcre-config  [--prefix] [--exec-prefix] [--version] [--libs]</b>
+<b>            [--libs16] [--libs32] [--libs-cpp] [--libs-posix]</b>
+<b>            [--cflags] [--cflags-posix]</b>
+</P>
+<br><a name="SEC2" href="#TOC1">DESCRIPTION</a><br>
+<P>
+<b>pcre-config</b> returns the configuration of the installed PCRE
+libraries and the options required to compile a program to use them. Some of
+the options apply only to the 8-bit, or 16-bit, or 32-bit libraries,
+respectively, and are
+not available if only one of those libraries has been built. If an unavailable
+option is encountered, the "usage" information is output.
+</P>
+<br><a name="SEC3" href="#TOC1">OPTIONS</a><br>
+<P>
+<b>--prefix</b>
+Writes the directory prefix used in the PCRE installation for architecture
+independent files (<i>/usr</i> on many systems, <i>/usr/local</i> on some
+systems) to the standard output.
+</P>
+<P>
+<b>--exec-prefix</b>
+Writes the directory prefix used in the PCRE installation for architecture
+dependent files (normally the same as <b>--prefix</b>) to the standard output.
+</P>
+<P>
+<b>--version</b>
+Writes the version number of the installed PCRE libraries to the standard
+output.
+</P>
+<P>
+<b>--libs</b>
+Writes to the standard output the command line options required to link
+with the 8-bit PCRE library (<b>-lpcre</b> on many systems).
+</P>
+<P>
+<b>--libs16</b>
+Writes to the standard output the command line options required to link
+with the 16-bit PCRE library (<b>-lpcre16</b> on many systems).
+</P>
+<P>
+<b>--libs32</b>
+Writes to the standard output the command line options required to link
+with the 32-bit PCRE library (<b>-lpcre32</b> on many systems).
+</P>
+<P>
+<b>--libs-cpp</b>
+Writes to the standard output the command line options required to link with
+PCRE's C++ wrapper library (<b>-lpcrecpp</b> <b>-lpcre</b> on many
+systems).
+</P>
+<P>
+<b>--libs-posix</b>
+Writes to the standard output the command line options required to link with
+PCRE's POSIX API wrapper library (<b>-lpcreposix</b> <b>-lpcre</b> on many
+systems).
+</P>
+<P>
+<b>--cflags</b>
+Writes to the standard output the command line options required to compile
+files that use PCRE (this may include some <b>-I</b> options, but is blank on
+many systems).
+</P>
+<P>
+<b>--cflags-posix</b>
+Writes to the standard output the command line options required to compile
+files that use PCRE's POSIX API wrapper library (this may include some <b>-I</b>
+options, but is blank on many systems).
+</P>
+<br><a name="SEC4" href="#TOC1">SEE ALSO</a><br>
+<P>
+<b>pcre(3)</b>
+</P>
+<br><a name="SEC5" href="#TOC1">AUTHOR</a><br>
+<P>
+This manual page was originally written by Mark Baker for the Debian GNU/Linux
+system. It has been subsequently revised as a generic PCRE man page.
+</P>
+<br><a name="SEC6" href="#TOC1">REVISION</a><br>
+<P>
+Last updated: 24 June 2012
+<br>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcre.html b/libs/Pcre16/docs/doc/html/pcre.html
new file mode 100644
index 0000000000..c2b29aa812
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcre.html
@@ -0,0 +1,213 @@
+<html>
+<head>
+<title>pcre specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcre man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<ul>
+<li><a name="TOC1" href="#SEC1">INTRODUCTION</a>
+<li><a name="TOC2" href="#SEC2">SECURITY CONSIDERATIONS</a>
+<li><a name="TOC3" href="#SEC3">USER DOCUMENTATION</a>
+<li><a name="TOC4" href="#SEC4">AUTHOR</a>
+<li><a name="TOC5" href="#SEC5">REVISION</a>
+</ul>
+<br><a name="SEC1" href="#TOC1">INTRODUCTION</a><br>
+<P>
+The PCRE library is a set of functions that implement regular expression
+pattern matching using the same syntax and semantics as Perl, with just a few
+differences. Some features that appeared in Python and PCRE before they
+appeared in Perl are also available using the Python syntax, there is some
+support for one or two .NET and Oniguruma syntax items, and there is an option
+for requesting some minor changes that give better JavaScript compatibility.
+</P>
+<P>
+Starting with release 8.30, it is possible to compile two separate PCRE
+libraries: the original, which supports 8-bit character strings (including
+UTF-8 strings), and a second library that supports 16-bit character strings
+(including UTF-16 strings). The build process allows either one or both to be
+built. The majority of the work to make this possible was done by Zoltan
+Herczeg.
+</P>
+<P>
+Starting with release 8.32 it is possible to compile a third separate PCRE
+library that supports 32-bit character strings (including UTF-32 strings). The
+build process allows any combination of the 8-, 16- and 32-bit libraries. The
+work to make this possible was done by Christian Persch.
+</P>
+<P>
+The three libraries contain identical sets of functions, except that the names
+in the 16-bit library start with <b>pcre16_</b> instead of <b>pcre_</b>, and the
+names in the 32-bit library start with <b>pcre32_</b> instead of <b>pcre_</b>. To
+avoid over-complication and reduce the documentation maintenance load, most of
+the documentation describes the 8-bit library, with the differences for the
+16-bit and 32-bit libraries described separately in the
+<a href="pcre16.html"><b>pcre16</b></a>
+and
+<a href="pcre32.html"><b>pcre32</b></a>
+pages. References to functions or structures of the form <i>pcre[16|32]_xxx</i>
+should be read as meaning "<i>pcre_xxx</i> when using the 8-bit library,
+<i>pcre16_xxx</i> when using the 16-bit library, or <i>pcre32_xxx</i> when using
+the 32-bit library".
+</P>
+<P>
+The current implementation of PCRE corresponds approximately with Perl 5.12,
+including support for UTF-8/16/32 encoded strings and Unicode general category
+properties. However, UTF-8/16/32 and Unicode support has to be explicitly
+enabled; it is not the default. The Unicode tables correspond to Unicode
+release 6.3.0.
+</P>
+<P>
+In addition to the Perl-compatible matching function, PCRE contains an
+alternative function that matches the same compiled patterns in a different
+way. In certain circumstances, the alternative function has some advantages.
+For a discussion of the two matching algorithms, see the
+<a href="pcrematching.html"><b>pcrematching</b></a>
+page.
+</P>
+<P>
+PCRE is written in C and released as a C library. A number of people have
+written wrappers and interfaces of various kinds. In particular, Google Inc.
+have provided a comprehensive C++ wrapper for the 8-bit library. This is now
+included as part of the PCRE distribution. The
+<a href="pcrecpp.html"><b>pcrecpp</b></a>
+page has details of this interface. Other people's contributions can be found
+in the <i>Contrib</i> directory at the primary FTP site, which is:
+<a href="ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre">ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre</a>
+</P>
+<P>
+Details of exactly which Perl regular expression features are and are not
+supported by PCRE are given in separate documents. See the
+<a href="pcrepattern.html"><b>pcrepattern</b></a>
+and
+<a href="pcrecompat.html"><b>pcrecompat</b></a>
+pages. There is a syntax summary in the
+<a href="pcresyntax.html"><b>pcresyntax</b></a>
+page.
+</P>
+<P>
+Some features of PCRE can be included, excluded, or changed when the library is
+built. The
+<a href="pcre_config.html"><b>pcre_config()</b></a>
+function makes it possible for a client to discover which features are
+available. The features themselves are described in the
+<a href="pcrebuild.html"><b>pcrebuild</b></a>
+page. Documentation about building PCRE for various operating systems can be
+found in the
+<a href="README.txt"><b>README</b></a>
+and
+<a href="NON-AUTOTOOLS-BUILD.txt"><b>NON-AUTOTOOLS_BUILD</b></a>
+files in the source distribution.
+</P>
+<P>
+The libraries contains a number of undocumented internal functions and data
+tables that are used by more than one of the exported external functions, but
+which are not intended for use by external callers. Their names all begin with
+"_pcre_" or "_pcre16_" or "_pcre32_", which hopefully will not provoke any name
+clashes. In some environments, it is possible to control which external symbols
+are exported when a shared library is built, and in these cases the
+undocumented symbols are not exported.
+</P>
+<br><a name="SEC2" href="#TOC1">SECURITY CONSIDERATIONS</a><br>
+<P>
+If you are using PCRE in a non-UTF application that permits users to supply
+arbitrary patterns for compilation, you should be aware of a feature that
+allows users to turn on UTF support from within a pattern, provided that PCRE
+was built with UTF support. For example, an 8-bit pattern that begins with
+"(*UTF8)" or "(*UTF)" turns on UTF-8 mode, which interprets patterns and
+subjects as strings of UTF-8 characters instead of individual 8-bit characters.
+This causes both the pattern and any data against which it is matched to be
+checked for UTF-8 validity. If the data string is very long, such a check might
+use sufficiently many resources as to cause your application to lose
+performance.
+</P>
+<P>
+One way of guarding against this possibility is to use the
+<b>pcre_fullinfo()</b> function to check the compiled pattern's options for UTF.
+Alternatively, from release 8.33, you can set the PCRE_NEVER_UTF option at
+compile time. This causes an compile time error if a pattern contains a
+UTF-setting sequence.
+</P>
+<P>
+If your application is one that supports UTF, be aware that validity checking
+can take time. If the same data string is to be matched many times, you can use
+the PCRE_NO_UTF[8|16|32]_CHECK option for the second and subsequent matches to
+save redundant checks.
+</P>
+<P>
+Another way that performance can be hit is by running a pattern that has a very
+large search tree against a string that will never match. Nested unlimited
+repeats in a pattern are a common example. PCRE provides some protection
+against this: see the PCRE_EXTRA_MATCH_LIMIT feature in the
+<a href="pcreapi.html"><b>pcreapi</b></a>
+page.
+</P>
+<br><a name="SEC3" href="#TOC1">USER DOCUMENTATION</a><br>
+<P>
+The user documentation for PCRE comprises a number of different sections. In
+the "man" format, each of these is a separate "man page". In the HTML format,
+each is a separate page, linked from the index page. In the plain text format,
+the descriptions of the <b>pcregrep</b> and <b>pcretest</b> programs are in files
+called <b>pcregrep.txt</b> and <b>pcretest.txt</b>, respectively. The remaining
+sections, except for the <b>pcredemo</b> section (which is a program listing),
+are concatenated in <b>pcre.txt</b>, for ease of searching. The sections are as
+follows:
+<pre>
+  pcre              this document
+  pcre-config       show PCRE installation configuration information
+  pcre16            details of the 16-bit library
+  pcre32            details of the 32-bit library
+  pcreapi           details of PCRE's native C API
+  pcrebuild         building PCRE
+  pcrecallout       details of the callout feature
+  pcrecompat        discussion of Perl compatibility
+  pcrecpp           details of the C++ wrapper for the 8-bit library
+  pcredemo          a demonstration C program that uses PCRE
+  pcregrep          description of the <b>pcregrep</b> command (8-bit only)
+  pcrejit           discussion of the just-in-time optimization support
+  pcrelimits        details of size and other limits
+  pcrematching      discussion of the two matching algorithms
+  pcrepartial       details of the partial matching facility
+  pcrepattern       syntax and semantics of supported regular expressions
+  pcreperform       discussion of performance issues
+  pcreposix         the POSIX-compatible C API for the 8-bit library
+  pcreprecompile    details of saving and re-using precompiled patterns
+  pcresample        discussion of the pcredemo program
+  pcrestack         discussion of stack usage
+  pcresyntax        quick syntax reference
+  pcretest          description of the <b>pcretest</b> testing command
+  pcreunicode       discussion of Unicode and UTF-8/16/32 support
+</pre>
+In the "man" and HTML formats, there is also a short page for each C library
+function, listing its arguments and results.
+</P>
+<br><a name="SEC4" href="#TOC1">AUTHOR</a><br>
+<P>
+Philip Hazel
+<br>
+University Computing Service
+<br>
+Cambridge CB2 3QH, England.
+<br>
+</P>
+<P>
+Putting an actual email address here seems to have been a spam magnet, so I've
+taken it away. If you want to email me, use my two initials, followed by the
+two digits 10, at the domain cam.ac.uk.
+</P>
+<br><a name="SEC5" href="#TOC1">REVISION</a><br>
+<P>
+Last updated: 08 January 2014
+<br>
+Copyright &copy; 1997-2014 University of Cambridge.
+<br>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcre16.html b/libs/Pcre16/docs/doc/html/pcre16.html
new file mode 100644
index 0000000000..f00859f052
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcre16.html
@@ -0,0 +1,384 @@
+<html>
+<head>
+<title>pcre16 specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcre16 man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<ul>
+<li><a name="TOC1" href="#SEC1">PCRE 16-BIT API BASIC FUNCTIONS</a>
+<li><a name="TOC2" href="#SEC2">PCRE 16-BIT API STRING EXTRACTION FUNCTIONS</a>
+<li><a name="TOC3" href="#SEC3">PCRE 16-BIT API AUXILIARY FUNCTIONS</a>
+<li><a name="TOC4" href="#SEC4">PCRE 16-BIT API INDIRECTED FUNCTIONS</a>
+<li><a name="TOC5" href="#SEC5">PCRE 16-BIT API 16-BIT-ONLY FUNCTION</a>
+<li><a name="TOC6" href="#SEC6">THE PCRE 16-BIT LIBRARY</a>
+<li><a name="TOC7" href="#SEC7">THE HEADER FILE</a>
+<li><a name="TOC8" href="#SEC8">THE LIBRARY NAME</a>
+<li><a name="TOC9" href="#SEC9">STRING TYPES</a>
+<li><a name="TOC10" href="#SEC10">STRUCTURE TYPES</a>
+<li><a name="TOC11" href="#SEC11">16-BIT FUNCTIONS</a>
+<li><a name="TOC12" href="#SEC12">SUBJECT STRING OFFSETS</a>
+<li><a name="TOC13" href="#SEC13">NAMED SUBPATTERNS</a>
+<li><a name="TOC14" href="#SEC14">OPTION NAMES</a>
+<li><a name="TOC15" href="#SEC15">CHARACTER CODES</a>
+<li><a name="TOC16" href="#SEC16">ERROR NAMES</a>
+<li><a name="TOC17" href="#SEC17">ERROR TEXTS</a>
+<li><a name="TOC18" href="#SEC18">CALLOUTS</a>
+<li><a name="TOC19" href="#SEC19">TESTING</a>
+<li><a name="TOC20" href="#SEC20">NOT SUPPORTED IN 16-BIT MODE</a>
+<li><a name="TOC21" href="#SEC21">AUTHOR</a>
+<li><a name="TOC22" href="#SEC22">REVISION</a>
+</ul>
+<P>
+<b>#include &#60;pcre.h&#62;</b>
+</P>
+<br><a name="SEC1" href="#TOC1">PCRE 16-BIT API BASIC FUNCTIONS</a><br>
+<P>
+<b>pcre16 *pcre16_compile(PCRE_SPTR16 <i>pattern</i>, int <i>options</i>,</b>
+<b>     const char **<i>errptr</i>, int *<i>erroffset</i>,</b>
+<b>     const unsigned char *<i>tableptr</i>);</b>
+<br>
+<br>
+<b>pcre16 *pcre16_compile2(PCRE_SPTR16 <i>pattern</i>, int <i>options</i>,</b>
+<b>     int *<i>errorcodeptr</i>,</b>
+<b>     const char **<i>errptr</i>, int *<i>erroffset</i>,</b>
+<b>     const unsigned char *<i>tableptr</i>);</b>
+<br>
+<br>
+<b>pcre16_extra *pcre16_study(const pcre16 *<i>code</i>, int <i>options</i>,</b>
+<b>     const char **<i>errptr</i>);</b>
+<br>
+<br>
+<b>void pcre16_free_study(pcre16_extra *<i>extra</i>);</b>
+<br>
+<br>
+<b>int pcre16_exec(const pcre16 *<i>code</i>, const pcre16_extra *<i>extra</i>,</b>
+<b>     PCRE_SPTR16 <i>subject</i>, int <i>length</i>, int <i>startoffset</i>,</b>
+<b>     int <i>options</i>, int *<i>ovector</i>, int <i>ovecsize</i>);</b>
+<br>
+<br>
+<b>int pcre16_dfa_exec(const pcre16 *<i>code</i>, const pcre16_extra *<i>extra</i>,</b>
+<b>     PCRE_SPTR16 <i>subject</i>, int <i>length</i>, int <i>startoffset</i>,</b>
+<b>     int <i>options</i>, int *<i>ovector</i>, int <i>ovecsize</i>,</b>
+<b>     int *<i>workspace</i>, int <i>wscount</i>);</b>
+</P>
+<br><a name="SEC2" href="#TOC1">PCRE 16-BIT API STRING EXTRACTION FUNCTIONS</a><br>
+<P>
+<b>int pcre16_copy_named_substring(const pcre16 *<i>code</i>,</b>
+<b>     PCRE_SPTR16 <i>subject</i>, int *<i>ovector</i>,</b>
+<b>     int <i>stringcount</i>, PCRE_SPTR16 <i>stringname</i>,</b>
+<b>     PCRE_UCHAR16 *<i>buffer</i>, int <i>buffersize</i>);</b>
+<br>
+<br>
+<b>int pcre16_copy_substring(PCRE_SPTR16 <i>subject</i>, int *<i>ovector</i>,</b>
+<b>     int <i>stringcount</i>, int <i>stringnumber</i>, PCRE_UCHAR16 *<i>buffer</i>,</b>
+<b>     int <i>buffersize</i>);</b>
+<br>
+<br>
+<b>int pcre16_get_named_substring(const pcre16 *<i>code</i>,</b>
+<b>     PCRE_SPTR16 <i>subject</i>, int *<i>ovector</i>,</b>
+<b>     int <i>stringcount</i>, PCRE_SPTR16 <i>stringname</i>,</b>
+<b>     PCRE_SPTR16 *<i>stringptr</i>);</b>
+<br>
+<br>
+<b>int pcre16_get_stringnumber(const pcre16 *<i>code</i>,</b>
+<b>"     PCRE_SPTR16 <i>name</i>);</b>
+<br>
+<br>
+<b>int pcre16_get_stringtable_entries(const pcre16 *<i>code</i>,</b>
+<b>     PCRE_SPTR16 <i>name</i>, PCRE_UCHAR16 **<i>first</i>, PCRE_UCHAR16 **<i>last</i>);</b>
+<br>
+<br>
+<b>int pcre16_get_substring(PCRE_SPTR16 <i>subject</i>, int *<i>ovector</i>,</b>
+<b>     int <i>stringcount</i>, int <i>stringnumber</i>,</b>
+<b>     PCRE_SPTR16 *<i>stringptr</i>);</b>
+<br>
+<br>
+<b>int pcre16_get_substring_list(PCRE_SPTR16 <i>subject</i>,</b>
+<b>     int *<i>ovector</i>, int <i>stringcount</i>, PCRE_SPTR16 **<i>listptr</i>);</b>
+<br>
+<br>
+<b>void pcre16_free_substring(PCRE_SPTR16 <i>stringptr</i>);</b>
+<br>
+<br>
+<b>void pcre16_free_substring_list(PCRE_SPTR16 *<i>stringptr</i>);</b>
+</P>
+<br><a name="SEC3" href="#TOC1">PCRE 16-BIT API AUXILIARY FUNCTIONS</a><br>
+<P>
+<b>pcre16_jit_stack *pcre16_jit_stack_alloc(int <i>startsize</i>, int <i>maxsize</i>);</b>
+<br>
+<br>
+<b>void pcre16_jit_stack_free(pcre16_jit_stack *<i>stack</i>);</b>
+<br>
+<br>
+<b>void pcre16_assign_jit_stack(pcre16_extra *<i>extra</i>,</b>
+<b>     pcre16_jit_callback <i>callback</i>, void *<i>data</i>);</b>
+<br>
+<br>
+<b>const unsigned char *pcre16_maketables(void);</b>
+<br>
+<br>
+<b>int pcre16_fullinfo(const pcre16 *<i>code</i>, const pcre16_extra *<i>extra</i>,</b>
+<b>     int <i>what</i>, void *<i>where</i>);</b>
+<br>
+<br>
+<b>int pcre16_refcount(pcre16 *<i>code</i>, int <i>adjust</i>);</b>
+<br>
+<br>
+<b>int pcre16_config(int <i>what</i>, void *<i>where</i>);</b>
+<br>
+<br>
+<b>const char *pcre16_version(void);</b>
+<br>
+<br>
+<b>int pcre16_pattern_to_host_byte_order(pcre16 *<i>code</i>,</b>
+<b>     pcre16_extra *<i>extra</i>, const unsigned char *<i>tables</i>);</b>
+</P>
+<br><a name="SEC4" href="#TOC1">PCRE 16-BIT API INDIRECTED FUNCTIONS</a><br>
+<P>
+<b>void *(*pcre16_malloc)(size_t);</b>
+<br>
+<br>
+<b>void (*pcre16_free)(void *);</b>
+<br>
+<br>
+<b>void *(*pcre16_stack_malloc)(size_t);</b>
+<br>
+<br>
+<b>void (*pcre16_stack_free)(void *);</b>
+<br>
+<br>
+<b>int (*pcre16_callout)(pcre16_callout_block *);</b>
+</P>
+<br><a name="SEC5" href="#TOC1">PCRE 16-BIT API 16-BIT-ONLY FUNCTION</a><br>
+<P>
+<b>int pcre16_utf16_to_host_byte_order(PCRE_UCHAR16 *<i>output</i>,</b>
+<b>     PCRE_SPTR16 <i>input</i>, int <i>length</i>, int *<i>byte_order</i>,</b>
+<b>     int <i>keep_boms</i>);</b>
+</P>
+<br><a name="SEC6" href="#TOC1">THE PCRE 16-BIT LIBRARY</a><br>
+<P>
+Starting with release 8.30, it is possible to compile a PCRE library that
+supports 16-bit character strings, including UTF-16 strings, as well as or
+instead of the original 8-bit library. The majority of the work to make this
+possible was done by Zoltan Herczeg. The two libraries contain identical sets
+of functions, used in exactly the same way. Only the names of the functions and
+the data types of their arguments and results are different. To avoid
+over-complication and reduce the documentation maintenance load, most of the
+PCRE documentation describes the 8-bit library, with only occasional references
+to the 16-bit library. This page describes what is different when you use the
+16-bit library.
+</P>
+<P>
+WARNING: A single application can be linked with both libraries, but you must
+take care when processing any particular pattern to use functions from just one
+library. For example, if you want to study a pattern that was compiled with
+<b>pcre16_compile()</b>, you must do so with <b>pcre16_study()</b>, not
+<b>pcre_study()</b>, and you must free the study data with
+<b>pcre16_free_study()</b>.
+</P>
+<br><a name="SEC7" href="#TOC1">THE HEADER FILE</a><br>
+<P>
+There is only one header file, <b>pcre.h</b>. It contains prototypes for all the
+functions in all libraries, as well as definitions of flags, structures, error
+codes, etc.
+</P>
+<br><a name="SEC8" href="#TOC1">THE LIBRARY NAME</a><br>
+<P>
+In Unix-like systems, the 16-bit library is called <b>libpcre16</b>, and can
+normally be accesss by adding <b>-lpcre16</b> to the command for linking an
+application that uses PCRE.
+</P>
+<br><a name="SEC9" href="#TOC1">STRING TYPES</a><br>
+<P>
+In the 8-bit library, strings are passed to PCRE library functions as vectors
+of bytes with the C type "char *". In the 16-bit library, strings are passed as
+vectors of unsigned 16-bit quantities. The macro PCRE_UCHAR16 specifies an
+appropriate data type, and PCRE_SPTR16 is defined as "const PCRE_UCHAR16 *". In
+very many environments, "short int" is a 16-bit data type. When PCRE is built,
+it defines PCRE_UCHAR16 as "unsigned short int", but checks that it really is a
+16-bit data type. If it is not, the build fails with an error message telling
+the maintainer to modify the definition appropriately.
+</P>
+<br><a name="SEC10" href="#TOC1">STRUCTURE TYPES</a><br>
+<P>
+The types of the opaque structures that are used for compiled 16-bit patterns
+and JIT stacks are <b>pcre16</b> and <b>pcre16_jit_stack</b> respectively. The
+type of the user-accessible structure that is returned by <b>pcre16_study()</b>
+is <b>pcre16_extra</b>, and the type of the structure that is used for passing
+data to a callout function is <b>pcre16_callout_block</b>. These structures
+contain the same fields, with the same names, as their 8-bit counterparts. The
+only difference is that pointers to character strings are 16-bit instead of
+8-bit types.
+</P>
+<br><a name="SEC11" href="#TOC1">16-BIT FUNCTIONS</a><br>
+<P>
+For every function in the 8-bit library there is a corresponding function in
+the 16-bit library with a name that starts with <b>pcre16_</b> instead of
+<b>pcre_</b>. The prototypes are listed above. In addition, there is one extra
+function, <b>pcre16_utf16_to_host_byte_order()</b>. This is a utility function
+that converts a UTF-16 character string to host byte order if necessary. The
+other 16-bit functions expect the strings they are passed to be in host byte
+order.
+</P>
+<P>
+The <i>input</i> and <i>output</i> arguments of
+<b>pcre16_utf16_to_host_byte_order()</b> may point to the same address, that is,
+conversion in place is supported. The output buffer must be at least as long as
+the input.
+</P>
+<P>
+The <i>length</i> argument specifies the number of 16-bit data units in the
+input string; a negative value specifies a zero-terminated string.
+</P>
+<P>
+If <i>byte_order</i> is NULL, it is assumed that the string starts off in host
+byte order. This may be changed by byte-order marks (BOMs) anywhere in the
+string (commonly as the first character).
+</P>
+<P>
+If <i>byte_order</i> is not NULL, a non-zero value of the integer to which it
+points means that the input starts off in host byte order, otherwise the
+opposite order is assumed. Again, BOMs in the string can change this. The final
+byte order is passed back at the end of processing.
+</P>
+<P>
+If <i>keep_boms</i> is not zero, byte-order mark characters (0xfeff) are copied
+into the output string. Otherwise they are discarded.
+</P>
+<P>
+The result of the function is the number of 16-bit units placed into the output
+buffer, including the zero terminator if the string was zero-terminated.
+</P>
+<br><a name="SEC12" href="#TOC1">SUBJECT STRING OFFSETS</a><br>
+<P>
+The lengths and starting offsets of subject strings must be specified in 16-bit
+data units, and the offsets within subject strings that are returned by the
+matching functions are in also 16-bit units rather than bytes.
+</P>
+<br><a name="SEC13" href="#TOC1">NAMED SUBPATTERNS</a><br>
+<P>
+The name-to-number translation table that is maintained for named subpatterns
+uses 16-bit characters. The <b>pcre16_get_stringtable_entries()</b> function
+returns the length of each entry in the table as the number of 16-bit data
+units.
+</P>
+<br><a name="SEC14" href="#TOC1">OPTION NAMES</a><br>
+<P>
+There are two new general option names, PCRE_UTF16 and PCRE_NO_UTF16_CHECK,
+which correspond to PCRE_UTF8 and PCRE_NO_UTF8_CHECK in the 8-bit library. In
+fact, these new options define the same bits in the options word. There is a
+discussion about the
+<a href="pcreunicode.html#utf16strings">validity of UTF-16 strings</a>
+in the
+<a href="pcreunicode.html"><b>pcreunicode</b></a>
+page.
+</P>
+<P>
+For the <b>pcre16_config()</b> function there is an option PCRE_CONFIG_UTF16
+that returns 1 if UTF-16 support is configured, otherwise 0. If this option is
+given to <b>pcre_config()</b> or <b>pcre32_config()</b>, or if the
+PCRE_CONFIG_UTF8 or PCRE_CONFIG_UTF32 option is given to <b>pcre16_config()</b>,
+the result is the PCRE_ERROR_BADOPTION error.
+</P>
+<br><a name="SEC15" href="#TOC1">CHARACTER CODES</a><br>
+<P>
+In 16-bit mode, when PCRE_UTF16 is not set, character values are treated in the
+same way as in 8-bit, non UTF-8 mode, except, of course, that they can range
+from 0 to 0xffff instead of 0 to 0xff. Character types for characters less than
+0xff can therefore be influenced by the locale in the same way as before.
+Characters greater than 0xff have only one case, and no "type" (such as letter
+or digit).
+</P>
+<P>
+In UTF-16 mode, the character code is Unicode, in the range 0 to 0x10ffff, with
+the exception of values in the range 0xd800 to 0xdfff because those are
+"surrogate" values that are used in pairs to encode values greater than 0xffff.
+</P>
+<P>
+A UTF-16 string can indicate its endianness by special code knows as a
+byte-order mark (BOM). The PCRE functions do not handle this, expecting strings
+to be in host byte order. A utility function called
+<b>pcre16_utf16_to_host_byte_order()</b> is provided to help with this (see
+above).
+</P>
+<br><a name="SEC16" href="#TOC1">ERROR NAMES</a><br>
+<P>
+The errors PCRE_ERROR_BADUTF16_OFFSET and PCRE_ERROR_SHORTUTF16 correspond to
+their 8-bit counterparts. The error PCRE_ERROR_BADMODE is given when a compiled
+pattern is passed to a function that processes patterns in the other
+mode, for example, if a pattern compiled with <b>pcre_compile()</b> is passed to
+<b>pcre16_exec()</b>.
+</P>
+<P>
+There are new error codes whose names begin with PCRE_UTF16_ERR for invalid
+UTF-16 strings, corresponding to the PCRE_UTF8_ERR codes for UTF-8 strings that
+are described in the section entitled
+<a href="pcreapi.html#badutf8reasons">"Reason codes for invalid UTF-8 strings"</a>
+in the main
+<a href="pcreapi.html"><b>pcreapi</b></a>
+page. The UTF-16 errors are:
+<pre>
+  PCRE_UTF16_ERR1  Missing low surrogate at end of string
+  PCRE_UTF16_ERR2  Invalid low surrogate follows high surrogate
+  PCRE_UTF16_ERR3  Isolated low surrogate
+  PCRE_UTF16_ERR4  Non-character
+</PRE>
+</P>
+<br><a name="SEC17" href="#TOC1">ERROR TEXTS</a><br>
+<P>
+If there is an error while compiling a pattern, the error text that is passed
+back by <b>pcre16_compile()</b> or <b>pcre16_compile2()</b> is still an 8-bit
+character string, zero-terminated.
+</P>
+<br><a name="SEC18" href="#TOC1">CALLOUTS</a><br>
+<P>
+The <i>subject</i> and <i>mark</i> fields in the callout block that is passed to
+a callout function point to 16-bit vectors.
+</P>
+<br><a name="SEC19" href="#TOC1">TESTING</a><br>
+<P>
+The <b>pcretest</b> program continues to operate with 8-bit input and output
+files, but it can be used for testing the 16-bit library. If it is run with the
+command line option <b>-16</b>, patterns and subject strings are converted from
+8-bit to 16-bit before being passed to PCRE, and the 16-bit library functions
+are used instead of the 8-bit ones. Returned 16-bit strings are converted to
+8-bit for output. If both the 8-bit and the 32-bit libraries were not compiled,
+<b>pcretest</b> defaults to 16-bit and the <b>-16</b> option is ignored.
+</P>
+<P>
+When PCRE is being built, the <b>RunTest</b> script that is called by "make
+check" uses the <b>pcretest</b> <b>-C</b> option to discover which of the 8-bit,
+16-bit and 32-bit libraries has been built, and runs the tests appropriately.
+</P>
+<br><a name="SEC20" href="#TOC1">NOT SUPPORTED IN 16-BIT MODE</a><br>
+<P>
+Not all the features of the 8-bit library are available with the 16-bit
+library. The C++ and POSIX wrapper functions support only the 8-bit library,
+and the <b>pcregrep</b> program is at present 8-bit only.
+</P>
+<br><a name="SEC21" href="#TOC1">AUTHOR</a><br>
+<P>
+Philip Hazel
+<br>
+University Computing Service
+<br>
+Cambridge CB2 3QH, England.
+<br>
+</P>
+<br><a name="SEC22" href="#TOC1">REVISION</a><br>
+<P>
+Last updated: 12 May 2013
+<br>
+Copyright &copy; 1997-2013 University of Cambridge.
+<br>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcre32.html b/libs/Pcre16/docs/doc/html/pcre32.html
new file mode 100644
index 0000000000..f96876e750
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcre32.html
@@ -0,0 +1,382 @@
+<html>
+<head>
+<title>pcre32 specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcre32 man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<ul>
+<li><a name="TOC1" href="#SEC1">PCRE 32-BIT API BASIC FUNCTIONS</a>
+<li><a name="TOC2" href="#SEC2">PCRE 32-BIT API STRING EXTRACTION FUNCTIONS</a>
+<li><a name="TOC3" href="#SEC3">PCRE 32-BIT API AUXILIARY FUNCTIONS</a>
+<li><a name="TOC4" href="#SEC4">PCRE 32-BIT API INDIRECTED FUNCTIONS</a>
+<li><a name="TOC5" href="#SEC5">PCRE 32-BIT API 32-BIT-ONLY FUNCTION</a>
+<li><a name="TOC6" href="#SEC6">THE PCRE 32-BIT LIBRARY</a>
+<li><a name="TOC7" href="#SEC7">THE HEADER FILE</a>
+<li><a name="TOC8" href="#SEC8">THE LIBRARY NAME</a>
+<li><a name="TOC9" href="#SEC9">STRING TYPES</a>
+<li><a name="TOC10" href="#SEC10">STRUCTURE TYPES</a>
+<li><a name="TOC11" href="#SEC11">32-BIT FUNCTIONS</a>
+<li><a name="TOC12" href="#SEC12">SUBJECT STRING OFFSETS</a>
+<li><a name="TOC13" href="#SEC13">NAMED SUBPATTERNS</a>
+<li><a name="TOC14" href="#SEC14">OPTION NAMES</a>
+<li><a name="TOC15" href="#SEC15">CHARACTER CODES</a>
+<li><a name="TOC16" href="#SEC16">ERROR NAMES</a>
+<li><a name="TOC17" href="#SEC17">ERROR TEXTS</a>
+<li><a name="TOC18" href="#SEC18">CALLOUTS</a>
+<li><a name="TOC19" href="#SEC19">TESTING</a>
+<li><a name="TOC20" href="#SEC20">NOT SUPPORTED IN 32-BIT MODE</a>
+<li><a name="TOC21" href="#SEC21">AUTHOR</a>
+<li><a name="TOC22" href="#SEC22">REVISION</a>
+</ul>
+<P>
+<b>#include &#60;pcre.h&#62;</b>
+</P>
+<br><a name="SEC1" href="#TOC1">PCRE 32-BIT API BASIC FUNCTIONS</a><br>
+<P>
+<b>pcre32 *pcre32_compile(PCRE_SPTR32 <i>pattern</i>, int <i>options</i>,</b>
+<b>     const char **<i>errptr</i>, int *<i>erroffset</i>,</b>
+<b>     const unsigned char *<i>tableptr</i>);</b>
+<br>
+<br>
+<b>pcre32 *pcre32_compile2(PCRE_SPTR32 <i>pattern</i>, int <i>options</i>,</b>
+<b>     int *<i>errorcodeptr</i>,</b>
+<b>     const unsigned char *<i>tableptr</i>);</b>
+<br>
+<br>
+<b>pcre32_extra *pcre32_study(const pcre32 *<i>code</i>, int <i>options</i>,</b>
+<b>     const char **<i>errptr</i>);</b>
+<br>
+<br>
+<b>void pcre32_free_study(pcre32_extra *<i>extra</i>);</b>
+<br>
+<br>
+<b>int pcre32_exec(const pcre32 *<i>code</i>, const pcre32_extra *<i>extra</i>,</b>
+<b>     PCRE_SPTR32 <i>subject</i>, int <i>length</i>, int <i>startoffset</i>,</b>
+<b>     int <i>options</i>, int *<i>ovector</i>, int <i>ovecsize</i>);</b>
+<br>
+<br>
+<b>int pcre32_dfa_exec(const pcre32 *<i>code</i>, const pcre32_extra *<i>extra</i>,</b>
+<b>     PCRE_SPTR32 <i>subject</i>, int <i>length</i>, int <i>startoffset</i>,</b>
+<b>     int <i>options</i>, int *<i>ovector</i>, int <i>ovecsize</i>,</b>
+<b>     int *<i>workspace</i>, int <i>wscount</i>);</b>
+</P>
+<br><a name="SEC2" href="#TOC1">PCRE 32-BIT API STRING EXTRACTION FUNCTIONS</a><br>
+<P>
+<b>int pcre32_copy_named_substring(const pcre32 *<i>code</i>,</b>
+<b>     PCRE_SPTR32 <i>subject</i>, int *<i>ovector</i>,</b>
+<b>     int <i>stringcount</i>, PCRE_SPTR32 <i>stringname</i>,</b>
+<b>     PCRE_UCHAR32 *<i>buffer</i>, int <i>buffersize</i>);</b>
+<br>
+<br>
+<b>int pcre32_copy_substring(PCRE_SPTR32 <i>subject</i>, int *<i>ovector</i>,</b>
+<b>     int <i>stringcount</i>, int <i>stringnumber</i>, PCRE_UCHAR32 *<i>buffer</i>,</b>
+<b>     int <i>buffersize</i>);</b>
+<br>
+<br>
+<b>int pcre32_get_named_substring(const pcre32 *<i>code</i>,</b>
+<b>     PCRE_SPTR32 <i>subject</i>, int *<i>ovector</i>,</b>
+<b>     int <i>stringcount</i>, PCRE_SPTR32 <i>stringname</i>,</b>
+<b>     PCRE_SPTR32 *<i>stringptr</i>);</b>
+<br>
+<br>
+<b>int pcre32_get_stringnumber(const pcre32 *<i>code</i>,</b>
+<b>     PCRE_SPTR32 <i>name</i>);</b>
+<br>
+<br>
+<b>int pcre32_get_stringtable_entries(const pcre32 *<i>code</i>,</b>
+<b>     PCRE_SPTR32 <i>name</i>, PCRE_UCHAR32 **<i>first</i>, PCRE_UCHAR32 **<i>last</i>);</b>
+<br>
+<br>
+<b>int pcre32_get_substring(PCRE_SPTR32 <i>subject</i>, int *<i>ovector</i>,</b>
+<b>     int <i>stringcount</i>, int <i>stringnumber</i>,</b>
+<b>     PCRE_SPTR32 *<i>stringptr</i>);</b>
+<br>
+<br>
+<b>int pcre32_get_substring_list(PCRE_SPTR32 <i>subject</i>,</b>
+<b>     int *<i>ovector</i>, int <i>stringcount</i>, PCRE_SPTR32 **<i>listptr</i>);</b>
+<br>
+<br>
+<b>void pcre32_free_substring(PCRE_SPTR32 <i>stringptr</i>);</b>
+<br>
+<br>
+<b>void pcre32_free_substring_list(PCRE_SPTR32 *<i>stringptr</i>);</b>
+</P>
+<br><a name="SEC3" href="#TOC1">PCRE 32-BIT API AUXILIARY FUNCTIONS</a><br>
+<P>
+<b>pcre32_jit_stack *pcre32_jit_stack_alloc(int <i>startsize</i>, int <i>maxsize</i>);</b>
+<br>
+<br>
+<b>void pcre32_jit_stack_free(pcre32_jit_stack *<i>stack</i>);</b>
+<br>
+<br>
+<b>void pcre32_assign_jit_stack(pcre32_extra *<i>extra</i>,</b>
+<b>     pcre32_jit_callback <i>callback</i>, void *<i>data</i>);</b>
+<br>
+<br>
+<b>const unsigned char *pcre32_maketables(void);</b>
+<br>
+<br>
+<b>int pcre32_fullinfo(const pcre32 *<i>code</i>, const pcre32_extra *<i>extra</i>,</b>
+<b>     int <i>what</i>, void *<i>where</i>);</b>
+<br>
+<br>
+<b>int pcre32_refcount(pcre32 *<i>code</i>, int <i>adjust</i>);</b>
+<br>
+<br>
+<b>int pcre32_config(int <i>what</i>, void *<i>where</i>);</b>
+<br>
+<br>
+<b>const char *pcre32_version(void);</b>
+<br>
+<br>
+<b>int pcre32_pattern_to_host_byte_order(pcre32 *<i>code</i>,</b>
+<b>     pcre32_extra *<i>extra</i>, const unsigned char *<i>tables</i>);</b>
+</P>
+<br><a name="SEC4" href="#TOC1">PCRE 32-BIT API INDIRECTED FUNCTIONS</a><br>
+<P>
+<b>void *(*pcre32_malloc)(size_t);</b>
+<br>
+<br>
+<b>void (*pcre32_free)(void *);</b>
+<br>
+<br>
+<b>void *(*pcre32_stack_malloc)(size_t);</b>
+<br>
+<br>
+<b>void (*pcre32_stack_free)(void *);</b>
+<br>
+<br>
+<b>int (*pcre32_callout)(pcre32_callout_block *);</b>
+</P>
+<br><a name="SEC5" href="#TOC1">PCRE 32-BIT API 32-BIT-ONLY FUNCTION</a><br>
+<P>
+<b>int pcre32_utf32_to_host_byte_order(PCRE_UCHAR32 *<i>output</i>,</b>
+<b>     PCRE_SPTR32 <i>input</i>, int <i>length</i>, int *<i>byte_order</i>,</b>
+<b>     int <i>keep_boms</i>);</b>
+</P>
+<br><a name="SEC6" href="#TOC1">THE PCRE 32-BIT LIBRARY</a><br>
+<P>
+Starting with release 8.32, it is possible to compile a PCRE library that
+supports 32-bit character strings, including UTF-32 strings, as well as or
+instead of the original 8-bit library. This work was done by Christian Persch,
+based on the work done by Zoltan Herczeg for the 16-bit library. All three
+libraries contain identical sets of functions, used in exactly the same way.
+Only the names of the functions and the data types of their arguments and
+results are different. To avoid over-complication and reduce the documentation
+maintenance load, most of the PCRE documentation describes the 8-bit library,
+with only occasional references to the 16-bit and 32-bit libraries. This page
+describes what is different when you use the 32-bit library.
+</P>
+<P>
+WARNING: A single application can be linked with all or any of the three
+libraries, but you must take care when processing any particular pattern
+to use functions from just one library. For example, if you want to study
+a pattern that was compiled with <b>pcre32_compile()</b>, you must do so
+with <b>pcre32_study()</b>, not <b>pcre_study()</b>, and you must free the
+study data with <b>pcre32_free_study()</b>.
+</P>
+<br><a name="SEC7" href="#TOC1">THE HEADER FILE</a><br>
+<P>
+There is only one header file, <b>pcre.h</b>. It contains prototypes for all the
+functions in all libraries, as well as definitions of flags, structures, error
+codes, etc.
+</P>
+<br><a name="SEC8" href="#TOC1">THE LIBRARY NAME</a><br>
+<P>
+In Unix-like systems, the 32-bit library is called <b>libpcre32</b>, and can
+normally be accesss by adding <b>-lpcre32</b> to the command for linking an
+application that uses PCRE.
+</P>
+<br><a name="SEC9" href="#TOC1">STRING TYPES</a><br>
+<P>
+In the 8-bit library, strings are passed to PCRE library functions as vectors
+of bytes with the C type "char *". In the 32-bit library, strings are passed as
+vectors of unsigned 32-bit quantities. The macro PCRE_UCHAR32 specifies an
+appropriate data type, and PCRE_SPTR32 is defined as "const PCRE_UCHAR32 *". In
+very many environments, "unsigned int" is a 32-bit data type. When PCRE is
+built, it defines PCRE_UCHAR32 as "unsigned int", but checks that it really is
+a 32-bit data type. If it is not, the build fails with an error message telling
+the maintainer to modify the definition appropriately.
+</P>
+<br><a name="SEC10" href="#TOC1">STRUCTURE TYPES</a><br>
+<P>
+The types of the opaque structures that are used for compiled 32-bit patterns
+and JIT stacks are <b>pcre32</b> and <b>pcre32_jit_stack</b> respectively. The
+type of the user-accessible structure that is returned by <b>pcre32_study()</b>
+is <b>pcre32_extra</b>, and the type of the structure that is used for passing
+data to a callout function is <b>pcre32_callout_block</b>. These structures
+contain the same fields, with the same names, as their 8-bit counterparts. The
+only difference is that pointers to character strings are 32-bit instead of
+8-bit types.
+</P>
+<br><a name="SEC11" href="#TOC1">32-BIT FUNCTIONS</a><br>
+<P>
+For every function in the 8-bit library there is a corresponding function in
+the 32-bit library with a name that starts with <b>pcre32_</b> instead of
+<b>pcre_</b>. The prototypes are listed above. In addition, there is one extra
+function, <b>pcre32_utf32_to_host_byte_order()</b>. This is a utility function
+that converts a UTF-32 character string to host byte order if necessary. The
+other 32-bit functions expect the strings they are passed to be in host byte
+order.
+</P>
+<P>
+The <i>input</i> and <i>output</i> arguments of
+<b>pcre32_utf32_to_host_byte_order()</b> may point to the same address, that is,
+conversion in place is supported. The output buffer must be at least as long as
+the input.
+</P>
+<P>
+The <i>length</i> argument specifies the number of 32-bit data units in the
+input string; a negative value specifies a zero-terminated string.
+</P>
+<P>
+If <i>byte_order</i> is NULL, it is assumed that the string starts off in host
+byte order. This may be changed by byte-order marks (BOMs) anywhere in the
+string (commonly as the first character).
+</P>
+<P>
+If <i>byte_order</i> is not NULL, a non-zero value of the integer to which it
+points means that the input starts off in host byte order, otherwise the
+opposite order is assumed. Again, BOMs in the string can change this. The final
+byte order is passed back at the end of processing.
+</P>
+<P>
+If <i>keep_boms</i> is not zero, byte-order mark characters (0xfeff) are copied
+into the output string. Otherwise they are discarded.
+</P>
+<P>
+The result of the function is the number of 32-bit units placed into the output
+buffer, including the zero terminator if the string was zero-terminated.
+</P>
+<br><a name="SEC12" href="#TOC1">SUBJECT STRING OFFSETS</a><br>
+<P>
+The lengths and starting offsets of subject strings must be specified in 32-bit
+data units, and the offsets within subject strings that are returned by the
+matching functions are in also 32-bit units rather than bytes.
+</P>
+<br><a name="SEC13" href="#TOC1">NAMED SUBPATTERNS</a><br>
+<P>
+The name-to-number translation table that is maintained for named subpatterns
+uses 32-bit characters. The <b>pcre32_get_stringtable_entries()</b> function
+returns the length of each entry in the table as the number of 32-bit data
+units.
+</P>
+<br><a name="SEC14" href="#TOC1">OPTION NAMES</a><br>
+<P>
+There are two new general option names, PCRE_UTF32 and PCRE_NO_UTF32_CHECK,
+which correspond to PCRE_UTF8 and PCRE_NO_UTF8_CHECK in the 8-bit library. In
+fact, these new options define the same bits in the options word. There is a
+discussion about the
+<a href="pcreunicode.html#utf32strings">validity of UTF-32 strings</a>
+in the
+<a href="pcreunicode.html"><b>pcreunicode</b></a>
+page.
+</P>
+<P>
+For the <b>pcre32_config()</b> function there is an option PCRE_CONFIG_UTF32
+that returns 1 if UTF-32 support is configured, otherwise 0. If this option is
+given to <b>pcre_config()</b> or <b>pcre16_config()</b>, or if the
+PCRE_CONFIG_UTF8 or PCRE_CONFIG_UTF16 option is given to <b>pcre32_config()</b>,
+the result is the PCRE_ERROR_BADOPTION error.
+</P>
+<br><a name="SEC15" href="#TOC1">CHARACTER CODES</a><br>
+<P>
+In 32-bit mode, when PCRE_UTF32 is not set, character values are treated in the
+same way as in 8-bit, non UTF-8 mode, except, of course, that they can range
+from 0 to 0x7fffffff instead of 0 to 0xff. Character types for characters less
+than 0xff can therefore be influenced by the locale in the same way as before.
+Characters greater than 0xff have only one case, and no "type" (such as letter
+or digit).
+</P>
+<P>
+In UTF-32 mode, the character code is Unicode, in the range 0 to 0x10ffff, with
+the exception of values in the range 0xd800 to 0xdfff because those are
+"surrogate" values that are ill-formed in UTF-32.
+</P>
+<P>
+A UTF-32 string can indicate its endianness by special code knows as a
+byte-order mark (BOM). The PCRE functions do not handle this, expecting strings
+to be in host byte order. A utility function called
+<b>pcre32_utf32_to_host_byte_order()</b> is provided to help with this (see
+above).
+</P>
+<br><a name="SEC16" href="#TOC1">ERROR NAMES</a><br>
+<P>
+The error PCRE_ERROR_BADUTF32 corresponds to its 8-bit counterpart.
+The error PCRE_ERROR_BADMODE is given when a compiled
+pattern is passed to a function that processes patterns in the other
+mode, for example, if a pattern compiled with <b>pcre_compile()</b> is passed to
+<b>pcre32_exec()</b>.
+</P>
+<P>
+There are new error codes whose names begin with PCRE_UTF32_ERR for invalid
+UTF-32 strings, corresponding to the PCRE_UTF8_ERR codes for UTF-8 strings that
+are described in the section entitled
+<a href="pcreapi.html#badutf8reasons">"Reason codes for invalid UTF-8 strings"</a>
+in the main
+<a href="pcreapi.html"><b>pcreapi</b></a>
+page. The UTF-32 errors are:
+<pre>
+  PCRE_UTF32_ERR1  Surrogate character (range from 0xd800 to 0xdfff)
+  PCRE_UTF32_ERR2  Non-character
+  PCRE_UTF32_ERR3  Character &#62; 0x10ffff
+</PRE>
+</P>
+<br><a name="SEC17" href="#TOC1">ERROR TEXTS</a><br>
+<P>
+If there is an error while compiling a pattern, the error text that is passed
+back by <b>pcre32_compile()</b> or <b>pcre32_compile2()</b> is still an 8-bit
+character string, zero-terminated.
+</P>
+<br><a name="SEC18" href="#TOC1">CALLOUTS</a><br>
+<P>
+The <i>subject</i> and <i>mark</i> fields in the callout block that is passed to
+a callout function point to 32-bit vectors.
+</P>
+<br><a name="SEC19" href="#TOC1">TESTING</a><br>
+<P>
+The <b>pcretest</b> program continues to operate with 8-bit input and output
+files, but it can be used for testing the 32-bit library. If it is run with the
+command line option <b>-32</b>, patterns and subject strings are converted from
+8-bit to 32-bit before being passed to PCRE, and the 32-bit library functions
+are used instead of the 8-bit ones. Returned 32-bit strings are converted to
+8-bit for output. If both the 8-bit and the 16-bit libraries were not compiled,
+<b>pcretest</b> defaults to 32-bit and the <b>-32</b> option is ignored.
+</P>
+<P>
+When PCRE is being built, the <b>RunTest</b> script that is called by "make
+check" uses the <b>pcretest</b> <b>-C</b> option to discover which of the 8-bit,
+16-bit and 32-bit libraries has been built, and runs the tests appropriately.
+</P>
+<br><a name="SEC20" href="#TOC1">NOT SUPPORTED IN 32-BIT MODE</a><br>
+<P>
+Not all the features of the 8-bit library are available with the 32-bit
+library. The C++ and POSIX wrapper functions support only the 8-bit library,
+and the <b>pcregrep</b> program is at present 8-bit only.
+</P>
+<br><a name="SEC21" href="#TOC1">AUTHOR</a><br>
+<P>
+Philip Hazel
+<br>
+University Computing Service
+<br>
+Cambridge CB2 3QH, England.
+<br>
+</P>
+<br><a name="SEC22" href="#TOC1">REVISION</a><br>
+<P>
+Last updated: 12 May 2013
+<br>
+Copyright &copy; 1997-2013 University of Cambridge.
+<br>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcre_assign_jit_stack.html b/libs/Pcre16/docs/doc/html/pcre_assign_jit_stack.html
new file mode 100644
index 0000000000..b2eef704db
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcre_assign_jit_stack.html
@@ -0,0 +1,76 @@
+<html>
+<head>
+<title>pcre_assign_jit_stack specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcre_assign_jit_stack man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<br><b>
+SYNOPSIS
+</b><br>
+<P>
+<b>#include &#60;pcre.h&#62;</b>
+</P>
+<P>
+<b>void pcre_assign_jit_stack(pcre_extra *<i>extra</i>,</b>
+<b>     pcre_jit_callback <i>callback</i>, void *<i>data</i>);</b>
+<br>
+<br>
+<b>void pcre16_assign_jit_stack(pcre16_extra *<i>extra</i>,</b>
+<b>     pcre16_jit_callback <i>callback</i>, void *<i>data</i>);</b>
+<br>
+<br>
+<b>void pcre32_assign_jit_stack(pcre32_extra *<i>extra</i>,</b>
+<b>     pcre32_jit_callback <i>callback</i>, void *<i>data</i>);</b>
+</P>
+<br><b>
+DESCRIPTION
+</b><br>
+<P>
+This function provides control over the memory used as a stack at run-time by a
+call to <b>pcre[16|32]_exec()</b> with a pattern that has been successfully
+compiled with JIT optimization. The arguments are:
+<pre>
+  extra     the data pointer returned by <b>pcre[16|32]_study()</b>
+  callback  a callback function
+  data      a JIT stack or a value to be passed to the callback
+              function
+</PRE>
+</P>
+<P>
+If <i>callback</i> is NULL and <i>data</i> is NULL, an internal 32K block on
+the machine stack is used.
+</P>
+<P>
+If <i>callback</i> is NULL and <i>data</i> is not NULL, <i>data</i> must
+be a valid JIT stack, the result of calling <b>pcre[16|32]_jit_stack_alloc()</b>.
+</P>
+<P>
+If <i>callback</i> not NULL, it is called with <i>data</i> as an argument at
+the start of matching, in order to set up a JIT stack. If the result is NULL,
+the internal 32K stack is used; otherwise the return value must be a valid JIT
+stack, the result of calling <b>pcre[16|32]_jit_stack_alloc()</b>.
+</P>
+<P>
+You may safely assign the same JIT stack to multiple patterns, as long as they
+are all matched in the same thread. In a multithread application, each thread
+must use its own JIT stack. For more details, see the
+<a href="pcrejit.html"><b>pcrejit</b></a>
+page.
+</P>
+<P>
+There is a complete description of the PCRE native API in the
+<a href="pcreapi.html"><b>pcreapi</b></a>
+page and a description of the POSIX API in the
+<a href="pcreposix.html"><b>pcreposix</b></a>
+page.
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcre_compile.html b/libs/Pcre16/docs/doc/html/pcre_compile.html
new file mode 100644
index 0000000000..95b4bec63c
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcre_compile.html
@@ -0,0 +1,111 @@
+<html>
+<head>
+<title>pcre_compile specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcre_compile man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<br><b>
+SYNOPSIS
+</b><br>
+<P>
+<b>#include &#60;pcre.h&#62;</b>
+</P>
+<P>
+<b>pcre *pcre_compile(const char *<i>pattern</i>, int <i>options</i>,</b>
+<b>     const char **<i>errptr</i>, int *<i>erroffset</i>,</b>
+<b>     const unsigned char *<i>tableptr</i>);</b>
+<br>
+<br>
+<b>pcre16 *pcre16_compile(PCRE_SPTR16 <i>pattern</i>, int <i>options</i>,</b>
+<b>     const char **<i>errptr</i>, int *<i>erroffset</i>,</b>
+<b>     const unsigned char *<i>tableptr</i>);</b>
+<br>
+<br>
+<b>pcre32 *pcre32_compile(PCRE_SPTR32 <i>pattern</i>, int <i>options</i>,</b>
+<b>     const char **<i>errptr</i>, int *<i>erroffset</i>,</b>
+<b>     const unsigned char *<i>tableptr</i>);</b>
+</P>
+<br><b>
+DESCRIPTION
+</b><br>
+<P>
+This function compiles a regular expression into an internal form. It is the
+same as <b>pcre[16|32]_compile2()</b>, except for the absence of the
+<i>errorcodeptr</i> argument. Its arguments are:
+<pre>
+  <i>pattern</i>       A zero-terminated string containing the
+                  regular expression to be compiled
+  <i>options</i>       Zero or more option bits
+  <i>errptr</i>        Where to put an error message
+  <i>erroffset</i>     Offset in pattern where error was found
+  <i>tableptr</i>      Pointer to character tables, or NULL to
+                  use the built-in default
+</pre>
+The option bits are:
+<pre>
+  PCRE_ANCHORED           Force pattern anchoring
+  PCRE_AUTO_CALLOUT       Compile automatic callouts
+  PCRE_BSR_ANYCRLF        \R matches only CR, LF, or CRLF
+  PCRE_BSR_UNICODE        \R matches all Unicode line endings
+  PCRE_CASELESS           Do caseless matching
+  PCRE_DOLLAR_ENDONLY     $ not to match newline at end
+  PCRE_DOTALL             . matches anything including NL
+  PCRE_DUPNAMES           Allow duplicate names for subpatterns
+  PCRE_EXTENDED           Ignore white space and # comments
+  PCRE_EXTRA              PCRE extra features
+                            (not much use currently)
+  PCRE_FIRSTLINE          Force matching to be before newline
+  PCRE_JAVASCRIPT_COMPAT  JavaScript compatibility
+  PCRE_MULTILINE          ^ and $ match newlines within data
+  PCRE_NEVER_UTF          Lock out UTF, e.g. via (*UTF)
+  PCRE_NEWLINE_ANY        Recognize any Unicode newline sequence
+  PCRE_NEWLINE_ANYCRLF    Recognize CR, LF, and CRLF as newline
+                            sequences
+  PCRE_NEWLINE_CR         Set CR as the newline sequence
+  PCRE_NEWLINE_CRLF       Set CRLF as the newline sequence
+  PCRE_NEWLINE_LF         Set LF as the newline sequence
+  PCRE_NO_AUTO_CAPTURE    Disable numbered capturing paren-
+                            theses (named ones available)
+  PCRE_NO_AUTO_POSSESS    Disable auto-possessification
+  PCRE_NO_START_OPTIMIZE  Disable match-time start optimizations
+  PCRE_NO_UTF16_CHECK     Do not check the pattern for UTF-16
+                            validity (only relevant if
+                            PCRE_UTF16 is set)
+  PCRE_NO_UTF32_CHECK     Do not check the pattern for UTF-32
+                            validity (only relevant if
+                            PCRE_UTF32 is set)
+  PCRE_NO_UTF8_CHECK      Do not check the pattern for UTF-8
+                            validity (only relevant if
+                            PCRE_UTF8 is set)
+  PCRE_UCP                Use Unicode properties for \d, \w, etc.
+  PCRE_UNGREEDY           Invert greediness of quantifiers
+  PCRE_UTF16              Run in <b>pcre16_compile()</b> UTF-16 mode
+  PCRE_UTF32              Run in <b>pcre32_compile()</b> UTF-32 mode
+  PCRE_UTF8               Run in <b>pcre_compile()</b> UTF-8 mode
+</pre>
+PCRE must be built with UTF support in order to use PCRE_UTF8/16/32 and
+PCRE_NO_UTF8/16/32_CHECK, and with UCP support if PCRE_UCP is used.
+</P>
+<P>
+The yield of the function is a pointer to a private data structure that
+contains the compiled pattern, or NULL if an error was detected. Note that
+compiling regular expressions with one version of PCRE for use with a different
+version is not guaranteed to work and may cause crashes.
+</P>
+<P>
+There is a complete description of the PCRE native API in the
+<a href="pcreapi.html"><b>pcreapi</b></a>
+page and a description of the POSIX API in the
+<a href="pcreposix.html"><b>pcreposix</b></a>
+page.
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcre_compile2.html b/libs/Pcre16/docs/doc/html/pcre_compile2.html
new file mode 100644
index 0000000000..9cd56a237b
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcre_compile2.html
@@ -0,0 +1,115 @@
+<html>
+<head>
+<title>pcre_compile2 specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcre_compile2 man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<br><b>
+SYNOPSIS
+</b><br>
+<P>
+<b>#include &#60;pcre.h&#62;</b>
+</P>
+<P>
+<b>pcre *pcre_compile2(const char *<i>pattern</i>, int <i>options</i>,</b>
+<b>     int *<i>errorcodeptr</i>,</b>
+<b>     const char **<i>errptr</i>, int *<i>erroffset</i>,</b>
+<b>     const unsigned char *<i>tableptr</i>);</b>
+<br>
+<br>
+<b>pcre16 *pcre16_compile2(PCRE_SPTR16 <i>pattern</i>, int <i>options</i>,</b>
+<b>     int *<i>errorcodeptr</i>,</b>
+<b>     const char **<i>errptr</i>, int *<i>erroffset</i>,</b>
+<b>     const unsigned char *<i>tableptr</i>);</b>
+<br>
+<br>
+<b>pcre32 *pcre32_compile2(PCRE_SPTR32 <i>pattern</i>, int <i>options</i>,</b>
+<b>"     int *<i>errorcodeptr</i>,£</b>
+<b>     const char **<i>errptr</i>, int *<i>erroffset</i>,</b>
+<b>     const unsigned char *<i>tableptr</i>);</b>
+</P>
+<br><b>
+DESCRIPTION
+</b><br>
+<P>
+This function compiles a regular expression into an internal form. It is the
+same as <b>pcre[16|32]_compile()</b>, except for the addition of the
+<i>errorcodeptr</i> argument. The arguments are:
+<pre>
+  <i>pattern</i>       A zero-terminated string containing the
+                  regular expression to be compiled
+  <i>options</i>       Zero or more option bits
+  <i>errorcodeptr</i>  Where to put an error code
+  <i>errptr</i>        Where to put an error message
+  <i>erroffset</i>     Offset in pattern where error was found
+  <i>tableptr</i>      Pointer to character tables, or NULL to
+                  use the built-in default
+</pre>
+The option bits are:
+<pre>
+  PCRE_ANCHORED           Force pattern anchoring
+  PCRE_AUTO_CALLOUT       Compile automatic callouts
+  PCRE_BSR_ANYCRLF        \R matches only CR, LF, or CRLF
+  PCRE_BSR_UNICODE        \R matches all Unicode line endings
+  PCRE_CASELESS           Do caseless matching
+  PCRE_DOLLAR_ENDONLY     $ not to match newline at end
+  PCRE_DOTALL             . matches anything including NL
+  PCRE_DUPNAMES           Allow duplicate names for subpatterns
+  PCRE_EXTENDED           Ignore white space and # comments
+  PCRE_EXTRA              PCRE extra features
+                            (not much use currently)
+  PCRE_FIRSTLINE          Force matching to be before newline
+  PCRE_JAVASCRIPT_COMPAT  JavaScript compatibility
+  PCRE_MULTILINE          ^ and $ match newlines within data
+  PCRE_NEVER_UTF          Lock out UTF, e.g. via (*UTF)
+  PCRE_NEWLINE_ANY        Recognize any Unicode newline sequence
+  PCRE_NEWLINE_ANYCRLF    Recognize CR, LF, and CRLF as newline
+                            sequences
+  PCRE_NEWLINE_CR         Set CR as the newline sequence
+  PCRE_NEWLINE_CRLF       Set CRLF as the newline sequence
+  PCRE_NEWLINE_LF         Set LF as the newline sequence
+  PCRE_NO_AUTO_CAPTURE    Disable numbered capturing paren-
+                            theses (named ones available)
+  PCRE_NO_AUTO_POSSESS    Disable auto-possessification
+  PCRE_NO_START_OPTIMIZE  Disable match-time start optimizations
+  PCRE_NO_UTF16_CHECK     Do not check the pattern for UTF-16
+                            validity (only relevant if
+                            PCRE_UTF16 is set)
+  PCRE_NO_UTF32_CHECK     Do not check the pattern for UTF-32
+                            validity (only relevant if
+                            PCRE_UTF32 is set)
+  PCRE_NO_UTF8_CHECK      Do not check the pattern for UTF-8
+                            validity (only relevant if
+                            PCRE_UTF8 is set)
+  PCRE_UCP                Use Unicode properties for \d, \w, etc.
+  PCRE_UNGREEDY           Invert greediness of quantifiers
+  PCRE_UTF16              Run <b>pcre16_compile()</b> in UTF-16 mode
+  PCRE_UTF32              Run <b>pcre32_compile()</b> in UTF-32 mode
+  PCRE_UTF8               Run <b>pcre_compile()</b> in UTF-8 mode
+</pre>
+PCRE must be built with UTF support in order to use PCRE_UTF8/16/32 and
+PCRE_NO_UTF8/16/32_CHECK, and with UCP support if PCRE_UCP is used.
+</P>
+<P>
+The yield of the function is a pointer to a private data structure that
+contains the compiled pattern, or NULL if an error was detected. Note that
+compiling regular expressions with one version of PCRE for use with a different
+version is not guaranteed to work and may cause crashes.
+</P>
+<P>
+There is a complete description of the PCRE native API in the
+<a href="pcreapi.html"><b>pcreapi</b></a>
+page and a description of the POSIX API in the
+<a href="pcreposix.html"><b>pcreposix</b></a>
+page.
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcre_config.html b/libs/Pcre16/docs/doc/html/pcre_config.html
new file mode 100644
index 0000000000..bcdcdded70
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcre_config.html
@@ -0,0 +1,92 @@
+<html>
+<head>
+<title>pcre_config specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcre_config man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<br><b>
+SYNOPSIS
+</b><br>
+<P>
+<b>#include &#60;pcre.h&#62;</b>
+</P>
+<P>
+<b>int pcre_config(int <i>what</i>, void *<i>where</i>);</b>
+</P>
+<P>
+<b>int pcre16_config(int <i>what</i>, void *<i>where</i>);</b>
+</P>
+<P>
+<b>int pcre32_config(int <i>what</i>, void *<i>where</i>);</b>
+</P>
+<br><b>
+DESCRIPTION
+</b><br>
+<P>
+This function makes it possible for a client program to find out which optional
+features are available in the version of the PCRE library it is using. The
+arguments are as follows:
+<pre>
+  <i>what</i>     A code specifying what information is required
+  <i>where</i>    Points to where to put the data
+</pre>
+The <i>where</i> argument must point to an integer variable, except for
+PCRE_CONFIG_MATCH_LIMIT and PCRE_CONFIG_MATCH_LIMIT_RECURSION, when it must
+point to an unsigned long integer. The available codes are:
+<pre>
+  PCRE_CONFIG_JIT           Availability of just-in-time compiler
+                              support (1=yes 0=no)
+  PCRE_CONFIG_JITTARGET     String containing information about the
+                              target architecture for the JIT compiler,
+                              or NULL if there is no JIT support
+  PCRE_CONFIG_LINK_SIZE     Internal link size: 2, 3, or 4
+  PCRE_CONFIG_PARENS_LIMIT  Parentheses nesting limit
+  PCRE_CONFIG_MATCH_LIMIT   Internal resource limit
+  PCRE_CONFIG_MATCH_LIMIT_RECURSION
+                            Internal recursion depth limit
+  PCRE_CONFIG_NEWLINE       Value of the default newline sequence:
+                                13 (0x000d)    for CR
+                                10 (0x000a)    for LF
+                              3338 (0x0d0a)    for CRLF
+                                -2             for ANYCRLF
+                                -1             for ANY
+  PCRE_CONFIG_BSR           Indicates what \R matches by default:
+                                 0             all Unicode line endings
+                                 1             CR, LF, or CRLF only
+  PCRE_CONFIG_POSIX_MALLOC_THRESHOLD
+                            Threshold of return slots, above which
+                              <b>malloc()</b> is used by the POSIX API
+  PCRE_CONFIG_STACKRECURSE  Recursion implementation (1=stack 0=heap)
+  PCRE_CONFIG_UTF16         Availability of UTF-16 support (1=yes
+                               0=no); option for <b>pcre16_config()</b>
+  PCRE_CONFIG_UTF32         Availability of UTF-32 support (1=yes
+                               0=no); option for <b>pcre32_config()</b>
+  PCRE_CONFIG_UTF8          Availability of UTF-8 support (1=yes 0=no);
+                              option for <b>pcre_config()</b>
+  PCRE_CONFIG_UNICODE_PROPERTIES
+                            Availability of Unicode property support
+                              (1=yes 0=no)
+</pre>
+The function yields 0 on success or PCRE_ERROR_BADOPTION otherwise. That error
+is also given if PCRE_CONFIG_UTF16 or PCRE_CONFIG_UTF32 is passed to
+<b>pcre_config()</b>, if PCRE_CONFIG_UTF8 or PCRE_CONFIG_UTF32 is passed to
+<b>pcre16_config()</b>, or if PCRE_CONFIG_UTF8 or PCRE_CONFIG_UTF16 is passed to
+<b>pcre32_config()</b>.
+</P>
+<P>
+There is a complete description of the PCRE native API in the
+<a href="pcreapi.html"><b>pcreapi</b></a>
+page and a description of the POSIX API in the
+<a href="pcreposix.html"><b>pcreposix</b></a>
+page.
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcre_copy_named_substring.html b/libs/Pcre16/docs/doc/html/pcre_copy_named_substring.html
new file mode 100644
index 0000000000..77b48043cd
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcre_copy_named_substring.html
@@ -0,0 +1,65 @@
+<html>
+<head>
+<title>pcre_copy_named_substring specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcre_copy_named_substring man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<br><b>
+SYNOPSIS
+</b><br>
+<P>
+<b>#include &#60;pcre.h&#62;</b>
+</P>
+<P>
+<b>int pcre_copy_named_substring(const pcre *<i>code</i>,</b>
+<b>     const char *<i>subject</i>, int *<i>ovector</i>,</b>
+<b>     int <i>stringcount</i>, const char *<i>stringname</i>,</b>
+<b>     char *<i>buffer</i>, int <i>buffersize</i>);</b>
+<br>
+<br>
+<b>int pcre16_copy_named_substring(const pcre16 *<i>code</i>,</b>
+<b>     PCRE_SPTR16 <i>subject</i>, int *<i>ovector</i>,</b>
+<b>     int <i>stringcount</i>, PCRE_SPTR16 <i>stringname</i>,</b>
+<b>     PCRE_UCHAR16 *<i>buffer</i>, int <i>buffersize</i>);</b>
+<br>
+<br>
+<b>int pcre32_copy_named_substring(const pcre32 *<i>code</i>,</b>
+<b>     PCRE_SPTR32 <i>subject</i>, int *<i>ovector</i>,</b>
+<b>     int <i>stringcount</i>, PCRE_SPTR32 <i>stringname</i>,</b>
+<b>     PCRE_UCHAR32 *<i>buffer</i>, int <i>buffersize</i>);</b>
+</P>
+<br><b>
+DESCRIPTION
+</b><br>
+<P>
+This is a convenience function for extracting a captured substring, identified
+by name, into a given buffer. The arguments are:
+<pre>
+  <i>code</i>          Pattern that was successfully matched
+  <i>subject</i>       Subject that has been successfully matched
+  <i>ovector</i>       Offset vector that <b>pcre[16|32]_exec()</b> used
+  <i>stringcount</i>   Value returned by <b>pcre[16|32]_exec()</b>
+  <i>stringname</i>    Name of the required substring
+  <i>buffer</i>        Buffer to receive the string
+  <i>buffersize</i>    Size of buffer
+</pre>
+The yield is the length of the substring, PCRE_ERROR_NOMEMORY if the buffer was
+too small, or PCRE_ERROR_NOSUBSTRING if the string name is invalid.
+</P>
+<P>
+There is a complete description of the PCRE native API in the
+<a href="pcreapi.html"><b>pcreapi</b></a>
+page and a description of the POSIX API in the
+<a href="pcreposix.html"><b>pcreposix</b></a>
+page.
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcre_copy_substring.html b/libs/Pcre16/docs/doc/html/pcre_copy_substring.html
new file mode 100644
index 0000000000..ecaebe8533
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcre_copy_substring.html
@@ -0,0 +1,61 @@
+<html>
+<head>
+<title>pcre_copy_substring specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcre_copy_substring man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<br><b>
+SYNOPSIS
+</b><br>
+<P>
+<b>#include &#60;pcre.h&#62;</b>
+</P>
+<P>
+<b>int pcre_copy_substring(const char *<i>subject</i>, int *<i>ovector</i>,</b>
+<b>     int <i>stringcount</i>, int <i>stringnumber</i>, char *<i>buffer</i>,</b>
+<b>     int <i>buffersize</i>);</b>
+<br>
+<br>
+<b>int pcre16_copy_substring(PCRE_SPTR16 <i>subject</i>, int *<i>ovector</i>,</b>
+<b>     int <i>stringcount</i>, int <i>stringnumber</i>, PCRE_UCHAR16 *<i>buffer</i>,</b>
+<b>     int <i>buffersize</i>);</b>
+<br>
+<br>
+<b>int pcre32_copy_substring(PCRE_SPTR32 <i>subject</i>, int *<i>ovector</i>,</b>
+<b>     int <i>stringcount</i>, int <i>stringnumber</i>, PCRE_UCHAR32 *<i>buffer</i>,</b>
+<b>     int <i>buffersize</i>);</b>
+</P>
+<br><b>
+DESCRIPTION
+</b><br>
+<P>
+This is a convenience function for extracting a captured substring into a given
+buffer. The arguments are:
+<pre>
+  <i>subject</i>       Subject that has been successfully matched
+  <i>ovector</i>       Offset vector that <b>pcre[16|32]_exec()</b> used
+  <i>stringcount</i>   Value returned by <b>pcre[16|32]_exec()</b>
+  <i>stringnumber</i>  Number of the required substring
+  <i>buffer</i>        Buffer to receive the string
+  <i>buffersize</i>    Size of buffer
+</pre>
+The yield is the length of the string, PCRE_ERROR_NOMEMORY if the buffer was
+too small, or PCRE_ERROR_NOSUBSTRING if the string number is invalid.
+</P>
+<P>
+There is a complete description of the PCRE native API in the
+<a href="pcreapi.html"><b>pcreapi</b></a>
+page and a description of the POSIX API in the
+<a href="pcreposix.html"><b>pcreposix</b></a>
+page.
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcre_dfa_exec.html b/libs/Pcre16/docs/doc/html/pcre_dfa_exec.html
new file mode 100644
index 0000000000..5fff6a7e0a
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcre_dfa_exec.html
@@ -0,0 +1,129 @@
+<html>
+<head>
+<title>pcre_dfa_exec specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcre_dfa_exec man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<br><b>
+SYNOPSIS
+</b><br>
+<P>
+<b>#include &#60;pcre.h&#62;</b>
+</P>
+<P>
+<b>int pcre_dfa_exec(const pcre *<i>code</i>, const pcre_extra *<i>extra</i>,</b>
+<b>     const char *<i>subject</i>, int <i>length</i>, int <i>startoffset</i>,</b>
+<b>     int <i>options</i>, int *<i>ovector</i>, int <i>ovecsize</i>,</b>
+<b>     int *<i>workspace</i>, int <i>wscount</i>);</b>
+<br>
+<br>
+<b>int pcre16_dfa_exec(const pcre16 *<i>code</i>, const pcre16_extra *<i>extra</i>,</b>
+<b>     PCRE_SPTR16 <i>subject</i>, int <i>length</i>, int <i>startoffset</i>,</b>
+<b>     int <i>options</i>, int *<i>ovector</i>, int <i>ovecsize</i>,</b>
+<b>     int *<i>workspace</i>, int <i>wscount</i>);</b>
+<br>
+<br>
+<b>int pcre32_dfa_exec(const pcre32 *<i>code</i>, const pcre32_extra *<i>extra</i>,</b>
+<b>     PCRE_SPTR32 <i>subject</i>, int <i>length</i>, int <i>startoffset</i>,</b>
+<b>     int <i>options</i>, int *<i>ovector</i>, int <i>ovecsize</i>,</b>
+<b>     int *<i>workspace</i>, int <i>wscount</i>);</b>
+</P>
+<br><b>
+DESCRIPTION
+</b><br>
+<P>
+This function matches a compiled regular expression against a given subject
+string, using an alternative matching algorithm that scans the subject string
+just once (<i>not</i> Perl-compatible). Note that the main, Perl-compatible,
+matching function is <b>pcre[16|32]_exec()</b>. The arguments for this function
+are:
+<pre>
+  <i>code</i>         Points to the compiled pattern
+  <i>extra</i>        Points to an associated <b>pcre[16|32]_extra</b> structure,
+                 or is NULL
+  <i>subject</i>      Points to the subject string
+  <i>length</i>       Length of the subject string
+  <i>startoffset</i>  Offset in the subject at which to start matching
+  <i>options</i>      Option bits
+  <i>ovector</i>      Points to a vector of ints for result offsets
+  <i>ovecsize</i>     Number of elements in the vector
+  <i>workspace</i>    Points to a vector of ints used as working space
+  <i>wscount</i>      Number of elements in the vector
+</pre>
+The units for <i>length</i> and <i>startoffset</i> are bytes for
+<b>pcre_exec()</b>, 16-bit data items for <b>pcre16_exec()</b>, and 32-bit items
+for <b>pcre32_exec()</b>. The options are:
+<pre>
+  PCRE_ANCHORED          Match only at the first position
+  PCRE_BSR_ANYCRLF       \R matches only CR, LF, or CRLF
+  PCRE_BSR_UNICODE       \R matches all Unicode line endings
+  PCRE_NEWLINE_ANY       Recognize any Unicode newline sequence
+  PCRE_NEWLINE_ANYCRLF   Recognize CR, LF, & CRLF as newline sequences
+  PCRE_NEWLINE_CR        Recognize CR as the only newline sequence
+  PCRE_NEWLINE_CRLF      Recognize CRLF as the only newline sequence
+  PCRE_NEWLINE_LF        Recognize LF as the only newline sequence
+  PCRE_NOTBOL            Subject is not the beginning of a line
+  PCRE_NOTEOL            Subject is not the end of a line
+  PCRE_NOTEMPTY          An empty string is not a valid match
+  PCRE_NOTEMPTY_ATSTART  An empty string at the start of the subject
+                           is not a valid match
+  PCRE_NO_START_OPTIMIZE Do not do "start-match" optimizations
+  PCRE_NO_UTF16_CHECK    Do not check the subject for UTF-16
+                           validity (only relevant if PCRE_UTF16
+                           was set at compile time)
+  PCRE_NO_UTF32_CHECK    Do not check the subject for UTF-32
+                           validity (only relevant if PCRE_UTF32
+                           was set at compile time)
+  PCRE_NO_UTF8_CHECK     Do not check the subject for UTF-8
+                           validity (only relevant if PCRE_UTF8
+                           was set at compile time)
+  PCRE_PARTIAL           ) Return PCRE_ERROR_PARTIAL for a partial
+  PCRE_PARTIAL_SOFT      )   match if no full matches are found
+  PCRE_PARTIAL_HARD      Return PCRE_ERROR_PARTIAL for a partial match
+                           even if there is a full match as well
+  PCRE_DFA_SHORTEST      Return only the shortest match
+  PCRE_DFA_RESTART       Restart after a partial match
+</pre>
+There are restrictions on what may appear in a pattern when using this matching
+function. Details are given in the
+<a href="pcrematching.html"><b>pcrematching</b></a>
+documentation. For details of partial matching, see the
+<a href="pcrepartial.html"><b>pcrepartial</b></a>
+page.
+</P>
+<P>
+A <b>pcre[16|32]_extra</b> structure contains the following fields:
+<pre>
+  <i>flags</i>            Bits indicating which fields are set
+  <i>study_data</i>       Opaque data from <b>pcre[16|32]_study()</b>
+  <i>match_limit</i>      Limit on internal resource use
+  <i>match_limit_recursion</i>  Limit on internal recursion depth
+  <i>callout_data</i>     Opaque data passed back to callouts
+  <i>tables</i>           Points to character tables or is NULL
+  <i>mark</i>             For passing back a *MARK pointer
+  <i>executable_jit</i>   Opaque data from JIT compilation
+</pre>
+The flag bits are PCRE_EXTRA_STUDY_DATA, PCRE_EXTRA_MATCH_LIMIT,
+PCRE_EXTRA_MATCH_LIMIT_RECURSION, PCRE_EXTRA_CALLOUT_DATA,
+PCRE_EXTRA_TABLES, PCRE_EXTRA_MARK and PCRE_EXTRA_EXECUTABLE_JIT. For this
+matching function, the <i>match_limit</i> and <i>match_limit_recursion</i> fields
+are not used, and must not be set. The PCRE_EXTRA_EXECUTABLE_JIT flag and
+the corresponding variable are ignored.
+</P>
+<P>
+There is a complete description of the PCRE native API in the
+<a href="pcreapi.html"><b>pcreapi</b></a>
+page and a description of the POSIX API in the
+<a href="pcreposix.html"><b>pcreposix</b></a>
+page.
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcre_exec.html b/libs/Pcre16/docs/doc/html/pcre_exec.html
new file mode 100644
index 0000000000..18e1a13ff8
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcre_exec.html
@@ -0,0 +1,111 @@
+<html>
+<head>
+<title>pcre_exec specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcre_exec man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<br><b>
+SYNOPSIS
+</b><br>
+<P>
+<b>#include &#60;pcre.h&#62;</b>
+</P>
+<P>
+<b>int pcre_exec(const pcre *<i>code</i>, const pcre_extra *<i>extra</i>,</b>
+<b>     const char *<i>subject</i>, int <i>length</i>, int <i>startoffset</i>,</b>
+<b>     int <i>options</i>, int *<i>ovector</i>, int <i>ovecsize</i>);</b>
+<br>
+<br>
+<b>int pcre16_exec(const pcre16 *<i>code</i>, const pcre16_extra *<i>extra</i>,</b>
+<b>     PCRE_SPTR16 <i>subject</i>, int <i>length</i>, int <i>startoffset</i>,</b>
+<b>     int <i>options</i>, int *<i>ovector</i>, int <i>ovecsize</i>);</b>
+<br>
+<br>
+<b>int pcre32_exec(const pcre32 *<i>code</i>, const pcre32_extra *<i>extra</i>,</b>
+<b>     PCRE_SPTR32 <i>subject</i>, int <i>length</i>, int <i>startoffset</i>,</b>
+<b>     int <i>options</i>, int *<i>ovector</i>, int <i>ovecsize</i>);</b>
+</P>
+<br><b>
+DESCRIPTION
+</b><br>
+<P>
+This function matches a compiled regular expression against a given subject
+string, using a matching algorithm that is similar to Perl's. It returns
+offsets to captured substrings. Its arguments are:
+<pre>
+  <i>code</i>         Points to the compiled pattern
+  <i>extra</i>        Points to an associated <b>pcre[16|32]_extra</b> structure,
+                 or is NULL
+  <i>subject</i>      Points to the subject string
+  <i>length</i>       Length of the subject string
+  <i>startoffset</i>  Offset in the subject at which to start matching
+  <i>options</i>      Option bits
+  <i>ovector</i>      Points to a vector of ints for result offsets
+  <i>ovecsize</i>     Number of elements in the vector (a multiple of 3)
+</pre>
+The units for <i>length</i> and <i>startoffset</i> are bytes for
+<b>pcre_exec()</b>, 16-bit data items for <b>pcre16_exec()</b>, and 32-bit items
+for <b>pcre32_exec()</b>. The options are:
+<pre>
+  PCRE_ANCHORED          Match only at the first position
+  PCRE_BSR_ANYCRLF       \R matches only CR, LF, or CRLF
+  PCRE_BSR_UNICODE       \R matches all Unicode line endings
+  PCRE_NEWLINE_ANY       Recognize any Unicode newline sequence
+  PCRE_NEWLINE_ANYCRLF   Recognize CR, LF, & CRLF as newline sequences
+  PCRE_NEWLINE_CR        Recognize CR as the only newline sequence
+  PCRE_NEWLINE_CRLF      Recognize CRLF as the only newline sequence
+  PCRE_NEWLINE_LF        Recognize LF as the only newline sequence
+  PCRE_NOTBOL            Subject string is not the beginning of a line
+  PCRE_NOTEOL            Subject string is not the end of a line
+  PCRE_NOTEMPTY          An empty string is not a valid match
+  PCRE_NOTEMPTY_ATSTART  An empty string at the start of the subject
+                           is not a valid match
+  PCRE_NO_START_OPTIMIZE Do not do "start-match" optimizations
+  PCRE_NO_UTF16_CHECK    Do not check the subject for UTF-16
+                           validity (only relevant if PCRE_UTF16
+                           was set at compile time)
+  PCRE_NO_UTF32_CHECK    Do not check the subject for UTF-32
+                           validity (only relevant if PCRE_UTF32
+                           was set at compile time)
+  PCRE_NO_UTF8_CHECK     Do not check the subject for UTF-8
+                           validity (only relevant if PCRE_UTF8
+                           was set at compile time)
+  PCRE_PARTIAL           ) Return PCRE_ERROR_PARTIAL for a partial
+  PCRE_PARTIAL_SOFT      )   match if no full matches are found
+  PCRE_PARTIAL_HARD      Return PCRE_ERROR_PARTIAL for a partial match
+                           if that is found before a full match
+</pre>
+For details of partial matching, see the
+<a href="pcrepartial.html"><b>pcrepartial</b></a>
+page. A <b>pcre_extra</b> structure contains the following fields:
+<pre>
+  <i>flags</i>            Bits indicating which fields are set
+  <i>study_data</i>       Opaque data from <b>pcre[16|32]_study()</b>
+  <i>match_limit</i>      Limit on internal resource use
+  <i>match_limit_recursion</i>  Limit on internal recursion depth
+  <i>callout_data</i>     Opaque data passed back to callouts
+  <i>tables</i>           Points to character tables or is NULL
+  <i>mark</i>             For passing back a *MARK pointer
+  <i>executable_jit</i>   Opaque data from JIT compilation
+</pre>
+The flag bits are PCRE_EXTRA_STUDY_DATA, PCRE_EXTRA_MATCH_LIMIT,
+PCRE_EXTRA_MATCH_LIMIT_RECURSION, PCRE_EXTRA_CALLOUT_DATA,
+PCRE_EXTRA_TABLES, PCRE_EXTRA_MARK and PCRE_EXTRA_EXECUTABLE_JIT.
+</P>
+<P>
+There is a complete description of the PCRE native API in the
+<a href="pcreapi.html"><b>pcreapi</b></a>
+page and a description of the POSIX API in the
+<a href="pcreposix.html"><b>pcreposix</b></a>
+page.
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcre_free_study.html b/libs/Pcre16/docs/doc/html/pcre_free_study.html
new file mode 100644
index 0000000000..7f9e10e863
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcre_free_study.html
@@ -0,0 +1,46 @@
+<html>
+<head>
+<title>pcre_free_study specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcre_free_study man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<br><b>
+SYNOPSIS
+</b><br>
+<P>
+<b>#include &#60;pcre.h&#62;</b>
+</P>
+<P>
+<b>void pcre_free_study(pcre_extra *<i>extra</i>);</b>
+</P>
+<P>
+<b>void pcre16_free_study(pcre16_extra *<i>extra</i>);</b>
+</P>
+<P>
+<b>void pcre32_free_study(pcre32_extra *<i>extra</i>);</b>
+</P>
+<br><b>
+DESCRIPTION
+</b><br>
+<P>
+This function is used to free the memory used for the data generated by a call
+to <b>pcre[16|32]_study()</b> when it is no longer needed. The argument must be the
+result of such a call.
+</P>
+<P>
+There is a complete description of the PCRE native API in the
+<a href="pcreapi.html"><b>pcreapi</b></a>
+page and a description of the POSIX API in the
+<a href="pcreposix.html"><b>pcreposix</b></a>
+page.
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcre_free_substring.html b/libs/Pcre16/docs/doc/html/pcre_free_substring.html
new file mode 100644
index 0000000000..1fe6610746
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcre_free_substring.html
@@ -0,0 +1,46 @@
+<html>
+<head>
+<title>pcre_free_substring specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcre_free_substring man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<br><b>
+SYNOPSIS
+</b><br>
+<P>
+<b>#include &#60;pcre.h&#62;</b>
+</P>
+<P>
+<b>void pcre_free_substring(const char *<i>stringptr</i>);</b>
+</P>
+<P>
+<b>void pcre16_free_substring(PCRE_SPTR16 <i>stringptr</i>);</b>
+</P>
+<P>
+<b>void pcre32_free_substring(PCRE_SPTR32 <i>stringptr</i>);</b>
+</P>
+<br><b>
+DESCRIPTION
+</b><br>
+<P>
+This is a convenience function for freeing the store obtained by a previous
+call to <b>pcre[16|32]_get_substring()</b> or <b>pcre[16|32]_get_named_substring()</b>.
+Its only argument is a pointer to the string.
+</P>
+<P>
+There is a complete description of the PCRE native API in the
+<a href="pcreapi.html"><b>pcreapi</b></a>
+page and a description of the POSIX API in the
+<a href="pcreposix.html"><b>pcreposix</b></a>
+page.
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcre_free_substring_list.html b/libs/Pcre16/docs/doc/html/pcre_free_substring_list.html
new file mode 100644
index 0000000000..c0861780b4
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcre_free_substring_list.html
@@ -0,0 +1,46 @@
+<html>
+<head>
+<title>pcre_free_substring_list specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcre_free_substring_list man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<br><b>
+SYNOPSIS
+</b><br>
+<P>
+<b>#include &#60;pcre.h&#62;</b>
+</P>
+<P>
+<b>void pcre_free_substring_list(const char **<i>stringptr</i>);</b>
+</P>
+<P>
+<b>void pcre16_free_substring_list(PCRE_SPTR16 *<i>stringptr</i>);</b>
+</P>
+<P>
+<b>void pcre32_free_substring_list(PCRE_SPTR32 *<i>stringptr</i>);</b>
+</P>
+<br><b>
+DESCRIPTION
+</b><br>
+<P>
+This is a convenience function for freeing the store obtained by a previous
+call to <b>pcre[16|32]_get_substring_list()</b>. Its only argument is a pointer to
+the list of string pointers.
+</P>
+<P>
+There is a complete description of the PCRE native API in the
+<a href="pcreapi.html"><b>pcreapi</b></a>
+page and a description of the POSIX API in the
+<a href="pcreposix.html"><b>pcreposix</b></a>
+page.
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcre_fullinfo.html b/libs/Pcre16/docs/doc/html/pcre_fullinfo.html
new file mode 100644
index 0000000000..b88fc1155b
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcre_fullinfo.html
@@ -0,0 +1,108 @@
+<html>
+<head>
+<title>pcre_fullinfo specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcre_fullinfo man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<br><b>
+SYNOPSIS
+</b><br>
+<P>
+<b>#include &#60;pcre.h&#62;</b>
+</P>
+<P>
+<b>int pcre_fullinfo(const pcre *<i>code</i>, const pcre_extra *<i>extra</i>,</b>
+<b>     int <i>what</i>, void *<i>where</i>);</b>
+<br>
+<br>
+<b>int pcre16_fullinfo(const pcre16 *<i>code</i>, const pcre16_extra *<i>extra</i>,</b>
+<b>     int <i>what</i>, void *<i>where</i>);</b>
+<br>
+<br>
+<b>int pcre32_fullinfo(const pcre32 *<i>code</i>, const pcre32_extra *<i>extra</i>,</b>
+<b>     int <i>what</i>, void *<i>where</i>);</b>
+</P>
+<br><b>
+DESCRIPTION
+</b><br>
+<P>
+This function returns information about a compiled pattern. Its arguments are:
+<pre>
+  <i>code</i>                      Compiled regular expression
+  <i>extra</i>                     Result of <b>pcre[16|32]_study()</b> or NULL
+  <i>what</i>                      What information is required
+  <i>where</i>                     Where to put the information
+</pre>
+The following information is available:
+<pre>
+  PCRE_INFO_BACKREFMAX      Number of highest back reference
+  PCRE_INFO_CAPTURECOUNT    Number of capturing subpatterns
+  PCRE_INFO_DEFAULT_TABLES  Pointer to default tables
+  PCRE_INFO_FIRSTBYTE       Fixed first data unit for a match, or
+                              -1 for start of string
+                                 or after newline, or
+                              -2 otherwise
+  PCRE_INFO_FIRSTTABLE      Table of first data units (after studying)
+  PCRE_INFO_HASCRORLF       Return 1 if explicit CR or LF matches exist
+  PCRE_INFO_JCHANGED        Return 1 if (?J) or (?-J) was used
+  PCRE_INFO_JIT             Return 1 after successful JIT compilation
+  PCRE_INFO_JITSIZE         Size of JIT compiled code
+  PCRE_INFO_LASTLITERAL     Literal last data unit required
+  PCRE_INFO_MINLENGTH       Lower bound length of matching strings
+  PCRE_INFO_NAMECOUNT       Number of named subpatterns
+  PCRE_INFO_NAMEENTRYSIZE   Size of name table entry
+  PCRE_INFO_NAMETABLE       Pointer to name table
+  PCRE_INFO_OKPARTIAL       Return 1 if partial matching can be tried
+                              (always returns 1 after release 8.00)
+  PCRE_INFO_OPTIONS         Option bits used for compilation
+  PCRE_INFO_SIZE            Size of compiled pattern
+  PCRE_INFO_STUDYSIZE       Size of study data
+  PCRE_INFO_FIRSTCHARACTER      Fixed first data unit for a match
+  PCRE_INFO_FIRSTCHARACTERFLAGS Returns
+                                  1 if there is a first data character set, which can
+                                    then be retrieved using PCRE_INFO_FIRSTCHARACTER,
+                                  2 if the first character is at the start of the data
+                                    string or after a newline, and
+                                  0 otherwise
+  PCRE_INFO_REQUIREDCHAR      Literal last data unit required
+  PCRE_INFO_REQUIREDCHARFLAGS Returns 1 if the last data character is set (which can then
+                              be retrieved using PCRE_INFO_REQUIREDCHAR); 0 otherwise
+</pre>
+The <i>where</i> argument must point to an integer variable, except for the
+following <i>what</i> values:
+<pre>
+  PCRE_INFO_DEFAULT_TABLES  const unsigned char *
+  PCRE_INFO_FIRSTTABLE      const unsigned char *
+  PCRE_INFO_NAMETABLE       PCRE_SPTR16           (16-bit library)
+  PCRE_INFO_NAMETABLE       PCRE_SPTR32           (32-bit library)
+  PCRE_INFO_NAMETABLE       const unsigned char * (8-bit library)
+  PCRE_INFO_OPTIONS         unsigned long int
+  PCRE_INFO_SIZE            size_t
+  PCRE_INFO_FIRSTCHARACTER  uint32_t
+  PCRE_INFO_REQUIREDCHAR    uint32_t
+</pre>
+The yield of the function is zero on success or:
+<pre>
+  PCRE_ERROR_NULL           the argument <i>code</i> was NULL
+                            the argument <i>where</i> was NULL
+  PCRE_ERROR_BADMAGIC       the "magic number" was not found
+  PCRE_ERROR_BADOPTION      the value of <i>what</i> was invalid
+</PRE>
+</P>
+<P>
+There is a complete description of the PCRE native API in the
+<a href="pcreapi.html"><b>pcreapi</b></a>
+page and a description of the POSIX API in the
+<a href="pcreposix.html"><b>pcreposix</b></a>
+page.
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcre_get_named_substring.html b/libs/Pcre16/docs/doc/html/pcre_get_named_substring.html
new file mode 100644
index 0000000000..72924d9b25
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcre_get_named_substring.html
@@ -0,0 +1,68 @@
+<html>
+<head>
+<title>pcre_get_named_substring specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcre_get_named_substring man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<br><b>
+SYNOPSIS
+</b><br>
+<P>
+<b>#include &#60;pcre.h&#62;</b>
+</P>
+<P>
+<b>int pcre_get_named_substring(const pcre *<i>code</i>,</b>
+<b>     const char *<i>subject</i>, int *<i>ovector</i>,</b>
+<b>     int <i>stringcount</i>, const char *<i>stringname</i>,</b>
+<b>     const char **<i>stringptr</i>);</b>
+<br>
+<br>
+<b>int pcre16_get_named_substring(const pcre16 *<i>code</i>,</b>
+<b>     PCRE_SPTR16 <i>subject</i>, int *<i>ovector</i>,</b>
+<b>     int <i>stringcount</i>, PCRE_SPTR16 <i>stringname</i>,</b>
+<b>     PCRE_SPTR16 *<i>stringptr</i>);</b>
+<br>
+<br>
+<b>int pcre32_get_named_substring(const pcre32 *<i>code</i>,</b>
+<b>     PCRE_SPTR32 <i>subject</i>, int *<i>ovector</i>,</b>
+<b>     int <i>stringcount</i>, PCRE_SPTR32 <i>stringname</i>,</b>
+<b>     PCRE_SPTR32 *<i>stringptr</i>);</b>
+</P>
+<br><b>
+DESCRIPTION
+</b><br>
+<P>
+This is a convenience function for extracting a captured substring by name. The
+arguments are:
+<pre>
+  <i>code</i>          Compiled pattern
+  <i>subject</i>       Subject that has been successfully matched
+  <i>ovector</i>       Offset vector that <b>pcre[16|32]_exec()</b> used
+  <i>stringcount</i>   Value returned by <b>pcre[16|32]_exec()</b>
+  <i>stringname</i>    Name of the required substring
+  <i>stringptr</i>     Where to put the string pointer
+</pre>
+The memory in which the substring is placed is obtained by calling
+<b>pcre[16|32]_malloc()</b>. The convenience function
+<b>pcre[16|32]_free_substring()</b> can be used to free it when it is no longer
+needed. The yield of the function is the length of the extracted substring,
+PCRE_ERROR_NOMEMORY if sufficient memory could not be obtained, or
+PCRE_ERROR_NOSUBSTRING if the string name is invalid.
+</P>
+<P>
+There is a complete description of the PCRE native API in the
+<a href="pcreapi.html"><b>pcreapi</b></a>
+page and a description of the POSIX API in the
+<a href="pcreposix.html"><b>pcreposix</b></a>
+page.
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcre_get_stringnumber.html b/libs/Pcre16/docs/doc/html/pcre_get_stringnumber.html
new file mode 100644
index 0000000000..7324d782e7
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcre_get_stringnumber.html
@@ -0,0 +1,57 @@
+<html>
+<head>
+<title>pcre_get_stringnumber specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcre_get_stringnumber man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<br><b>
+SYNOPSIS
+</b><br>
+<P>
+<b>#include &#60;pcre.h&#62;</b>
+</P>
+<P>
+<b>int pcre_get_stringnumber(const pcre *<i>code</i>,</b>
+<b>     const char *<i>name</i>);</b>
+<br>
+<br>
+<b>int pcre16_get_stringnumber(const pcre16 *<i>code</i>,</b>
+<b>     PCRE_SPTR16 <i>name</i>);</b>
+<br>
+<br>
+<b>int pcre32_get_stringnumber(const pcre32 *<i>code</i>,</b>
+<b>     PCRE_SPTR32 <i>name</i>);</b>
+</P>
+<br><b>
+DESCRIPTION
+</b><br>
+<P>
+This convenience function finds the number of a named substring capturing
+parenthesis in a compiled pattern. Its arguments are:
+<pre>
+  <i>code</i>    Compiled regular expression
+  <i>name</i>    Name whose number is required
+</pre>
+The yield of the function is the number of the parenthesis if the name is
+found, or PCRE_ERROR_NOSUBSTRING otherwise. When duplicate names are allowed
+(PCRE_DUPNAMES is set), it is not defined which of the numbers is returned by
+<b>pcre[16|32]_get_stringnumber()</b>. You can obtain the complete list by calling
+<b>pcre[16|32]_get_stringtable_entries()</b>.
+</P>
+<P>
+There is a complete description of the PCRE native API in the
+<a href="pcreapi.html"><b>pcreapi</b></a>
+page and a description of the POSIX API in the
+<a href="pcreposix.html"><b>pcreposix</b></a>
+page.
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcre_get_stringtable_entries.html b/libs/Pcre16/docs/doc/html/pcre_get_stringtable_entries.html
new file mode 100644
index 0000000000..79906798e6
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcre_get_stringtable_entries.html
@@ -0,0 +1,60 @@
+<html>
+<head>
+<title>pcre_get_stringtable_entries specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcre_get_stringtable_entries man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<br><b>
+SYNOPSIS
+</b><br>
+<P>
+<b>#include &#60;pcre.h&#62;</b>
+</P>
+<P>
+<b>int pcre_get_stringtable_entries(const pcre *<i>code</i>,</b>
+<b>     const char *<i>name</i>, char **<i>first</i>, char **<i>last</i>);</b>
+<br>
+<br>
+<b>int pcre16_get_stringtable_entries(const pcre16 *<i>code</i>,</b>
+<b>     PCRE_SPTR16 <i>name</i>, PCRE_UCHAR16 **<i>first</i>, PCRE_UCHAR16 **<i>last</i>);</b>
+<br>
+<br>
+<b>int pcre32_get_stringtable_entries(const pcre32 *<i>code</i>,</b>
+<b>     PCRE_SPTR32 <i>name</i>, PCRE_UCHAR32 **<i>first</i>, PCRE_UCHAR32 **<i>last</i>);</b>
+</P>
+<br><b>
+DESCRIPTION
+</b><br>
+<P>
+This convenience function finds, for a compiled pattern, the first and last
+entries for a given name in the table that translates capturing parenthesis
+names into numbers. When names are required to be unique (PCRE_DUPNAMES is
+<i>not</i> set), it is usually easier to use <b>pcre[16|32]_get_stringnumber()</b>
+instead.
+<pre>
+  <i>code</i>    Compiled regular expression
+  <i>name</i>    Name whose entries required
+  <i>first</i>   Where to return a pointer to the first entry
+  <i>last</i>    Where to return a pointer to the last entry
+</pre>
+The yield of the function is the length of each entry, or
+PCRE_ERROR_NOSUBSTRING if none are found.
+</P>
+<P>
+There is a complete description of the PCRE native API, including the format of
+the table entries, in the
+<a href="pcreapi.html"><b>pcreapi</b></a>
+page, and a description of the POSIX API in the
+<a href="pcreposix.html"><b>pcreposix</b></a>
+page.
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcre_get_substring.html b/libs/Pcre16/docs/doc/html/pcre_get_substring.html
new file mode 100644
index 0000000000..1a8e4f5a49
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcre_get_substring.html
@@ -0,0 +1,64 @@
+<html>
+<head>
+<title>pcre_get_substring specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcre_get_substring man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<br><b>
+SYNOPSIS
+</b><br>
+<P>
+<b>#include &#60;pcre.h&#62;</b>
+</P>
+<P>
+<b>int pcre_get_substring(const char *<i>subject</i>, int *<i>ovector</i>,</b>
+<b>     int <i>stringcount</i>, int <i>stringnumber</i>,</b>
+<b>     const char **<i>stringptr</i>);</b>
+<br>
+<br>
+<b>int pcre16_get_substring(PCRE_SPTR16 <i>subject</i>, int *<i>ovector</i>,</b>
+<b>     int <i>stringcount</i>, int <i>stringnumber</i>,</b>
+<b>     PCRE_SPTR16 *<i>stringptr</i>);</b>
+<br>
+<br>
+<b>int pcre32_get_substring(PCRE_SPTR32 <i>subject</i>, int *<i>ovector</i>,</b>
+<b>     int <i>stringcount</i>, int <i>stringnumber</i>,</b>
+<b>     PCRE_SPTR32 *<i>stringptr</i>);</b>
+</P>
+<br><b>
+DESCRIPTION
+</b><br>
+<P>
+This is a convenience function for extracting a captured substring. The
+arguments are:
+<pre>
+  <i>subject</i>       Subject that has been successfully matched
+  <i>ovector</i>       Offset vector that <b>pcre[16|32]_exec()</b> used
+  <i>stringcount</i>   Value returned by <b>pcre[16|32]_exec()</b>
+  <i>stringnumber</i>  Number of the required substring
+  <i>stringptr</i>     Where to put the string pointer
+</pre>
+The memory in which the substring is placed is obtained by calling
+<b>pcre[16|32]_malloc()</b>. The convenience function
+<b>pcre[16|32]_free_substring()</b> can be used to free it when it is no longer
+needed. The yield of the function is the length of the substring,
+PCRE_ERROR_NOMEMORY if sufficient memory could not be obtained, or
+PCRE_ERROR_NOSUBSTRING if the string number is invalid.
+</P>
+<P>
+There is a complete description of the PCRE native API in the
+<a href="pcreapi.html"><b>pcreapi</b></a>
+page and a description of the POSIX API in the
+<a href="pcreposix.html"><b>pcreposix</b></a>
+page.
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcre_get_substring_list.html b/libs/Pcre16/docs/doc/html/pcre_get_substring_list.html
new file mode 100644
index 0000000000..7e8c6bc858
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcre_get_substring_list.html
@@ -0,0 +1,61 @@
+<html>
+<head>
+<title>pcre_get_substring_list specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcre_get_substring_list man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<br><b>
+SYNOPSIS
+</b><br>
+<P>
+<b>#include &#60;pcre.h&#62;</b>
+</P>
+<P>
+<b>int pcre_get_substring_list(const char *<i>subject</i>,</b>
+<b>     int *<i>ovector</i>, int <i>stringcount</i>, const char ***<i>listptr</i>);</b>
+<br>
+<br>
+<b>int pcre16_get_substring_list(PCRE_SPTR16 <i>subject</i>,</b>
+<b>     int *<i>ovector</i>, int <i>stringcount</i>, PCRE_SPTR16 **<i>listptr</i>);</b>
+<br>
+<br>
+<b>int pcre32_get_substring_list(PCRE_SPTR32 <i>subject</i>,</b>
+<b>     int *<i>ovector</i>, int <i>stringcount</i>, PCRE_SPTR32 **<i>listptr</i>);</b>
+</P>
+<br><b>
+DESCRIPTION
+</b><br>
+<P>
+This is a convenience function for extracting a list of all the captured
+substrings. The arguments are:
+<pre>
+  <i>subject</i>       Subject that has been successfully matched
+  <i>ovector</i>       Offset vector that <b>pcre[16|32]_exec</b> used
+  <i>stringcount</i>   Value returned by <b>pcre[16|32]_exec</b>
+  <i>listptr</i>       Where to put a pointer to the list
+</pre>
+The memory in which the substrings and the list are placed is obtained by
+calling <b>pcre[16|32]_malloc()</b>. The convenience function
+<b>pcre[16|32]_free_substring_list()</b> can be used to free it when it is no
+longer needed. A pointer to a list of pointers is put in the variable whose
+address is in <i>listptr</i>. The list is terminated by a NULL pointer. The
+yield of the function is zero on success or PCRE_ERROR_NOMEMORY if sufficient
+memory could not be obtained.
+</P>
+<P>
+There is a complete description of the PCRE native API in the
+<a href="pcreapi.html"><b>pcreapi</b></a>
+page and a description of the POSIX API in the
+<a href="pcreposix.html"><b>pcreposix</b></a>
+page.
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcre_jit_exec.html b/libs/Pcre16/docs/doc/html/pcre_jit_exec.html
new file mode 100644
index 0000000000..4ebb0cbcac
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcre_jit_exec.html
@@ -0,0 +1,108 @@
+<html>
+<head>
+<title>pcre_jit_exec specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcre_jit_exec man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<br><b>
+SYNOPSIS
+</b><br>
+<P>
+<b>#include &#60;pcre.h&#62;</b>
+</P>
+<P>
+<b>int pcre_jit_exec(const pcre *<i>code</i>, const pcre_extra *<i>extra</i>,</b>
+<b>     const char *<i>subject</i>, int <i>length</i>, int <i>startoffset</i>,</b>
+<b>     int <i>options</i>, int *<i>ovector</i>, int <i>ovecsize</i>,</b>
+<b>     pcre_jit_stack *<i>jstack</i>);</b>
+<br>
+<br>
+<b>int pcre16_jit_exec(const pcre16 *<i>code</i>, const pcre16_extra *<i>extra</i>,</b>
+<b>     PCRE_SPTR16 <i>subject</i>, int <i>length</i>, int <i>startoffset</i>,</b>
+<b>     int <i>options</i>, int *<i>ovector</i>, int <i>ovecsize</i>,</b>
+<b>     pcre_jit_stack *<i>jstack</i>);</b>
+<br>
+<br>
+<b>int pcre32_jit_exec(const pcre32 *<i>code</i>, const pcre32_extra *<i>extra</i>,</b>
+<b>     PCRE_SPTR32 <i>subject</i>, int <i>length</i>, int <i>startoffset</i>,</b>
+<b>     int <i>options</i>, int *<i>ovector</i>, int <i>ovecsize</i>,</b>
+<b>     pcre_jit_stack *<i>jstack</i>);</b>
+</P>
+<br><b>
+DESCRIPTION
+</b><br>
+<P>
+This function matches a compiled regular expression that has been successfully
+studied with one of the JIT options against a given subject string, using a
+matching algorithm that is similar to Perl's. It is a "fast path" interface to
+JIT, and it bypasses some of the sanity checks that <b>pcre_exec()</b> applies.
+It returns offsets to captured substrings. Its arguments are:
+<pre>
+  <i>code</i>         Points to the compiled pattern
+  <i>extra</i>        Points to an associated <b>pcre[16|32]_extra</b> structure,
+                 or is NULL
+  <i>subject</i>      Points to the subject string
+  <i>length</i>       Length of the subject string, in bytes
+  <i>startoffset</i>  Offset in bytes in the subject at which to
+                 start matching
+  <i>options</i>      Option bits
+  <i>ovector</i>      Points to a vector of ints for result offsets
+  <i>ovecsize</i>     Number of elements in the vector (a multiple of 3)
+  <i>jstack</i>       Pointer to a JIT stack
+</pre>
+The allowed options are:
+<pre>
+  PCRE_NOTBOL            Subject string is not the beginning of a line
+  PCRE_NOTEOL            Subject string is not the end of a line
+  PCRE_NOTEMPTY          An empty string is not a valid match
+  PCRE_NOTEMPTY_ATSTART  An empty string at the start of the subject
+                           is not a valid match
+  PCRE_NO_UTF16_CHECK    Do not check the subject for UTF-16
+                           validity (only relevant if PCRE_UTF16
+                           was set at compile time)
+  PCRE_NO_UTF32_CHECK    Do not check the subject for UTF-32
+                           validity (only relevant if PCRE_UTF32
+                           was set at compile time)
+  PCRE_NO_UTF8_CHECK     Do not check the subject for UTF-8
+                           validity (only relevant if PCRE_UTF8
+                           was set at compile time)
+  PCRE_PARTIAL           ) Return PCRE_ERROR_PARTIAL for a partial
+  PCRE_PARTIAL_SOFT      )   match if no full matches are found
+  PCRE_PARTIAL_HARD      Return PCRE_ERROR_PARTIAL for a partial match
+                           if that is found before a full match
+</pre>
+However, the PCRE_NO_UTF[8|16|32]_CHECK options have no effect, as this check
+is never applied. For details of partial matching, see the
+<a href="pcrepartial.html"><b>pcrepartial</b></a>
+page. A <b>pcre_extra</b> structure contains the following fields:
+<pre>
+  <i>flags</i>            Bits indicating which fields are set
+  <i>study_data</i>       Opaque data from <b>pcre[16|32]_study()</b>
+  <i>match_limit</i>      Limit on internal resource use
+  <i>match_limit_recursion</i>  Limit on internal recursion depth
+  <i>callout_data</i>     Opaque data passed back to callouts
+  <i>tables</i>           Points to character tables or is NULL
+  <i>mark</i>             For passing back a *MARK pointer
+  <i>executable_jit</i>   Opaque data from JIT compilation
+</pre>
+The flag bits are PCRE_EXTRA_STUDY_DATA, PCRE_EXTRA_MATCH_LIMIT,
+PCRE_EXTRA_MATCH_LIMIT_RECURSION, PCRE_EXTRA_CALLOUT_DATA,
+PCRE_EXTRA_TABLES, PCRE_EXTRA_MARK and PCRE_EXTRA_EXECUTABLE_JIT.
+</P>
+<P>
+There is a complete description of the PCRE native API in the
+<a href="pcreapi.html"><b>pcreapi</b></a>
+page and a description of the JIT API in the
+<a href="pcrejit.html"><b>pcrejit</b></a>
+page.
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcre_jit_stack_alloc.html b/libs/Pcre16/docs/doc/html/pcre_jit_stack_alloc.html
new file mode 100644
index 0000000000..23ba450750
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcre_jit_stack_alloc.html
@@ -0,0 +1,55 @@
+<html>
+<head>
+<title>pcre_jit_stack_alloc specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcre_jit_stack_alloc man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<br><b>
+SYNOPSIS
+</b><br>
+<P>
+<b>#include &#60;pcre.h&#62;</b>
+</P>
+<P>
+<b>pcre_jit_stack *pcre_jit_stack_alloc(int <i>startsize</i>,</b>
+<b>     int <i>maxsize</i>);</b>
+<br>
+<br>
+<b>pcre16_jit_stack *pcre16_jit_stack_alloc(int <i>startsize</i>,</b>
+<b>     int <i>maxsize</i>);</b>
+<br>
+<br>
+<b>pcre32_jit_stack *pcre32_jit_stack_alloc(int <i>startsize</i>,</b>
+<b>     int <i>maxsize</i>);</b>
+</P>
+<br><b>
+DESCRIPTION
+</b><br>
+<P>
+This function is used to create a stack for use by the code compiled by the JIT
+optimization of <b>pcre[16|32]_study()</b>. The arguments are a starting size for
+the stack, and a maximum size to which it is allowed to grow. The result can be
+passed to the JIT run-time code by <b>pcre[16|32]_assign_jit_stack()</b>, or that
+function can set up a callback for obtaining a stack. A maximum stack size of
+512K to 1M should be more than enough for any pattern. For more details, see
+the
+<a href="pcrejit.html"><b>pcrejit</b></a>
+page.
+</P>
+<P>
+There is a complete description of the PCRE native API in the
+<a href="pcreapi.html"><b>pcreapi</b></a>
+page and a description of the POSIX API in the
+<a href="pcreposix.html"><b>pcreposix</b></a>
+page.
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcre_jit_stack_free.html b/libs/Pcre16/docs/doc/html/pcre_jit_stack_free.html
new file mode 100644
index 0000000000..8bd06e4655
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcre_jit_stack_free.html
@@ -0,0 +1,48 @@
+<html>
+<head>
+<title>pcre_jit_stack_free specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcre_jit_stack_free man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<br><b>
+SYNOPSIS
+</b><br>
+<P>
+<b>#include &#60;pcre.h&#62;</b>
+</P>
+<P>
+<b>void pcre_jit_stack_free(pcre_jit_stack *<i>stack</i>);</b>
+</P>
+<P>
+<b>void pcre16_jit_stack_free(pcre16_jit_stack *<i>stack</i>);</b>
+</P>
+<P>
+<b>void pcre32_jit_stack_free(pcre32_jit_stack *<i>stack</i>);</b>
+</P>
+<br><b>
+DESCRIPTION
+</b><br>
+<P>
+This function is used to free a JIT stack that was created by
+<b>pcre[16|32]_jit_stack_alloc()</b> when it is no longer needed. For more details,
+see the
+<a href="pcrejit.html"><b>pcrejit</b></a>
+page.
+</P>
+<P>
+There is a complete description of the PCRE native API in the
+<a href="pcreapi.html"><b>pcreapi</b></a>
+page and a description of the POSIX API in the
+<a href="pcreposix.html"><b>pcreposix</b></a>
+page.
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcre_maketables.html b/libs/Pcre16/docs/doc/html/pcre_maketables.html
new file mode 100644
index 0000000000..3a7b5ebc4a
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcre_maketables.html
@@ -0,0 +1,48 @@
+<html>
+<head>
+<title>pcre_maketables specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcre_maketables man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<br><b>
+SYNOPSIS
+</b><br>
+<P>
+<b>#include &#60;pcre.h&#62;</b>
+</P>
+<P>
+<b>const unsigned char *pcre_maketables(void);</b>
+</P>
+<P>
+<b>const unsigned char *pcre16_maketables(void);</b>
+</P>
+<P>
+<b>const unsigned char *pcre32_maketables(void);</b>
+</P>
+<br><b>
+DESCRIPTION
+</b><br>
+<P>
+This function builds a set of character tables for character values less than
+256. These can be passed to <b>pcre[16|32]_compile()</b> to override PCRE's
+internal, built-in tables (which were made by <b>pcre[16|32]_maketables()</b> when
+PCRE was compiled). You might want to do this if you are using a non-standard
+locale. The function yields a pointer to the tables.
+</P>
+<P>
+There is a complete description of the PCRE native API in the
+<a href="pcreapi.html"><b>pcreapi</b></a>
+page and a description of the POSIX API in the
+<a href="pcreposix.html"><b>pcreposix</b></a>
+page.
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcre_pattern_to_host_byte_order.html b/libs/Pcre16/docs/doc/html/pcre_pattern_to_host_byte_order.html
new file mode 100644
index 0000000000..1b1c80372b
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcre_pattern_to_host_byte_order.html
@@ -0,0 +1,58 @@
+<html>
+<head>
+<title>pcre_pattern_to_host_byte_order specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcre_pattern_to_host_byte_order man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<br><b>
+SYNOPSIS
+</b><br>
+<P>
+<b>#include &#60;pcre.h&#62;</b>
+</P>
+<P>
+<b>int pcre_pattern_to_host_byte_order(pcre *<i>code</i>,</b>
+<b>     pcre_extra *<i>extra</i>, const unsigned char *<i>tables</i>);</b>
+<br>
+<br>
+<b>int pcre16_pattern_to_host_byte_order(pcre16 *<i>code</i>,</b>
+<b>     pcre16_extra *<i>extra</i>, const unsigned char *<i>tables</i>);</b>
+<br>
+<br>
+<b>int pcre32_pattern_to_host_byte_order(pcre32 *<i>code</i>,</b>
+<b>     pcre32_extra *<i>extra</i>, const unsigned char *<i>tables</i>);</b>
+</P>
+<br><b>
+DESCRIPTION
+</b><br>
+<P>
+This function ensures that the bytes in 2-byte and 4-byte values in a compiled
+pattern are in the correct order for the current host. It is useful when a
+pattern that has been compiled on one host is transferred to another that might
+have different endianness. The arguments are:
+<pre>
+  <i>code</i>         A compiled regular expression
+  <i>extra</i>        Points to an associated <b>pcre[16|32]_extra</b> structure,
+                 or is NULL
+  <i>tables</i>       Pointer to character tables, or NULL to
+                 set the built-in default
+</pre>
+The result is 0 for success, a negative PCRE_ERROR_xxx value otherwise.
+</P>
+<P>
+There is a complete description of the PCRE native API in the
+<a href="pcreapi.html"><b>pcreapi</b></a>
+page and a description of the POSIX API in the
+<a href="pcreposix.html"><b>pcreposix</b></a>
+page.
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcre_refcount.html b/libs/Pcre16/docs/doc/html/pcre_refcount.html
new file mode 100644
index 0000000000..bfb92e6d8a
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcre_refcount.html
@@ -0,0 +1,51 @@
+<html>
+<head>
+<title>pcre_refcount specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcre_refcount man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<br><b>
+SYNOPSIS
+</b><br>
+<P>
+<b>#include &#60;pcre.h&#62;</b>
+</P>
+<P>
+<b>int pcre_refcount(pcre *<i>code</i>, int <i>adjust</i>);</b>
+</P>
+<P>
+<b>int pcre16_refcount(pcre16 *<i>code</i>, int <i>adjust</i>);</b>
+</P>
+<P>
+<b>int pcre32_refcount(pcre32 *<i>code</i>, int <i>adjust</i>);</b>
+</P>
+<br><b>
+DESCRIPTION
+</b><br>
+<P>
+This function is used to maintain a reference count inside a data block that
+contains a compiled pattern. Its arguments are:
+<pre>
+  <i>code</i>                      Compiled regular expression
+  <i>adjust</i>                    Adjustment to reference value
+</pre>
+The yield of the function is the adjusted reference value, which is constrained
+to lie between 0 and 65535.
+</P>
+<P>
+There is a complete description of the PCRE native API in the
+<a href="pcreapi.html"><b>pcreapi</b></a>
+page and a description of the POSIX API in the
+<a href="pcreposix.html"><b>pcreposix</b></a>
+page.
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcre_study.html b/libs/Pcre16/docs/doc/html/pcre_study.html
new file mode 100644
index 0000000000..af82f11409
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcre_study.html
@@ -0,0 +1,68 @@
+<html>
+<head>
+<title>pcre_study specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcre_study man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<br><b>
+SYNOPSIS
+</b><br>
+<P>
+<b>#include &#60;pcre.h&#62;</b>
+</P>
+<P>
+<b>pcre_extra *pcre_study(const pcre *<i>code</i>, int <i>options</i>,</b>
+<b>     const char **<i>errptr</i>);</b>
+<br>
+<br>
+<b>pcre16_extra *pcre16_study(const pcre16 *<i>code</i>, int <i>options</i>,</b>
+<b>     const char **<i>errptr</i>);</b>
+<br>
+<br>
+<b>pcre32_extra *pcre32_study(const pcre32 *<i>code</i>, int <i>options</i>,</b>
+<b>     const char **<i>errptr</i>);</b>
+</P>
+<br><b>
+DESCRIPTION
+</b><br>
+<P>
+This function studies a compiled pattern, to see if additional information can
+be extracted that might speed up matching. Its arguments are:
+<pre>
+  <i>code</i>       A compiled regular expression
+  <i>options</i>    Options for <b>pcre[16|32]_study()</b>
+  <i>errptr</i>     Where to put an error message
+</pre>
+If the function succeeds, it returns a value that can be passed to
+<b>pcre[16|32]_exec()</b> or <b>pcre[16|32]_dfa_exec()</b> via their <i>extra</i>
+arguments.
+</P>
+<P>
+If the function returns NULL, either it could not find any additional
+information, or there was an error. You can tell the difference by looking at
+the error value. It is NULL in first case.
+</P>
+<P>
+The only option is PCRE_STUDY_JIT_COMPILE. It requests just-in-time compilation
+if possible. If PCRE has been compiled without JIT support, this option is
+ignored. See the
+<a href="pcrejit.html"><b>pcrejit</b></a>
+page for further details.
+</P>
+<P>
+There is a complete description of the PCRE native API in the
+<a href="pcreapi.html"><b>pcreapi</b></a>
+page and a description of the POSIX API in the
+<a href="pcreposix.html"><b>pcreposix</b></a>
+page.
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcre_utf16_to_host_byte_order.html b/libs/Pcre16/docs/doc/html/pcre_utf16_to_host_byte_order.html
new file mode 100644
index 0000000000..18e7788f68
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcre_utf16_to_host_byte_order.html
@@ -0,0 +1,57 @@
+<html>
+<head>
+<title>pcre_utf16_to_host_byte_order specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcre_utf16_to_host_byte_order man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<br><b>
+SYNOPSIS
+</b><br>
+<P>
+<b>#include &#60;pcre.h&#62;</b>
+</P>
+<P>
+<b>int pcre16_utf16_to_host_byte_order(PCRE_UCHAR16 *<i>output</i>,</b>
+<b>     PCRE_SPTR16 <i>input</i>, int <i>length</i>, int *<i>host_byte_order</i>,</b>
+<b>     int <i>keep_boms</i>);</b>
+</P>
+<br><b>
+DESCRIPTION
+</b><br>
+<P>
+This function, which exists only in the 16-bit library, converts a UTF-16
+string to the correct order for the current host, taking account of any byte
+order marks (BOMs) within the string. Its arguments are:
+<pre>
+  <i>output</i>           pointer to output buffer, may be the same as <i>input</i>
+  <i>input</i>            pointer to input buffer
+  <i>length</i>           number of 16-bit units in the input, or negative for
+                     a zero-terminated string
+  <i>host_byte_order</i>  a NULL value or a non-zero value pointed to means
+                     start in host byte order
+  <i>keep_boms</i>        if non-zero, BOMs are copied to the output string
+</pre>
+The result of the function is the number of 16-bit units placed into the output
+buffer, including the zero terminator if the string was zero-terminated.
+</P>
+<P>
+If <i>host_byte_order</i> is not NULL, it is set to indicate the byte order that
+is current at the end of the string.
+</P>
+<P>
+There is a complete description of the PCRE native API in the
+<a href="pcreapi.html"><b>pcreapi</b></a>
+page and a description of the POSIX API in the
+<a href="pcreposix.html"><b>pcreposix</b></a>
+page.
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcre_utf32_to_host_byte_order.html b/libs/Pcre16/docs/doc/html/pcre_utf32_to_host_byte_order.html
new file mode 100644
index 0000000000..772ae40cd9
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcre_utf32_to_host_byte_order.html
@@ -0,0 +1,57 @@
+<html>
+<head>
+<title>pcre_utf32_to_host_byte_order specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcre_utf32_to_host_byte_order man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<br><b>
+SYNOPSIS
+</b><br>
+<P>
+<b>#include &#60;pcre.h&#62;</b>
+</P>
+<P>
+<b>int pcre32_utf32_to_host_byte_order(PCRE_UCHAR32 *<i>output</i>,</b>
+<b>     PCRE_SPTR32 <i>input</i>, int <i>length</i>, int *<i>host_byte_order</i>,</b>
+<b>     int <i>keep_boms</i>);</b>
+</P>
+<br><b>
+DESCRIPTION
+</b><br>
+<P>
+This function, which exists only in the 32-bit library, converts a UTF-32
+string to the correct order for the current host, taking account of any byte
+order marks (BOMs) within the string. Its arguments are:
+<pre>
+  <i>output</i>           pointer to output buffer, may be the same as <i>input</i>
+  <i>input</i>            pointer to input buffer
+  <i>length</i>           number of 32-bit units in the input, or negative for
+                     a zero-terminated string
+  <i>host_byte_order</i>  a NULL value or a non-zero value pointed to means
+                     start in host byte order
+  <i>keep_boms</i>        if non-zero, BOMs are copied to the output string
+</pre>
+The result of the function is the number of 32-bit units placed into the output
+buffer, including the zero terminator if the string was zero-terminated.
+</P>
+<P>
+If <i>host_byte_order</i> is not NULL, it is set to indicate the byte order that
+is current at the end of the string.
+</P>
+<P>
+There is a complete description of the PCRE native API in the
+<a href="pcreapi.html"><b>pcreapi</b></a>
+page and a description of the POSIX API in the
+<a href="pcreposix.html"><b>pcreposix</b></a>
+page.
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcre_version.html b/libs/Pcre16/docs/doc/html/pcre_version.html
new file mode 100644
index 0000000000..d33e718955
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcre_version.html
@@ -0,0 +1,46 @@
+<html>
+<head>
+<title>pcre_version specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcre_version man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<br><b>
+SYNOPSIS
+</b><br>
+<P>
+<b>#include &#60;pcre.h&#62;</b>
+</P>
+<P>
+<b>const char *pcre_version(void);</b>
+</P>
+<P>
+<b>const char *pcre16_version(void);</b>
+</P>
+<P>
+<b>const char *pcre32_version(void);</b>
+</P>
+<br><b>
+DESCRIPTION
+</b><br>
+<P>
+This function (even in the 16-bit and 32-bit libraries) returns a
+zero-terminated, 8-bit character string that gives the version number of the
+PCRE library and the date of its release.
+</P>
+<P>
+There is a complete description of the PCRE native API in the
+<a href="pcreapi.html"><b>pcreapi</b></a>
+page and a description of the POSIX API in the
+<a href="pcreposix.html"><b>pcreposix</b></a>
+page.
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcreapi.html b/libs/Pcre16/docs/doc/html/pcreapi.html
new file mode 100644
index 0000000000..b401ecc76d
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcreapi.html
@@ -0,0 +1,2922 @@
+<html>
+<head>
+<title>pcreapi specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcreapi man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<ul>
+<li><a name="TOC1" href="#SEC1">PCRE NATIVE API BASIC FUNCTIONS</a>
+<li><a name="TOC2" href="#SEC2">PCRE NATIVE API STRING EXTRACTION FUNCTIONS</a>
+<li><a name="TOC3" href="#SEC3">PCRE NATIVE API AUXILIARY FUNCTIONS</a>
+<li><a name="TOC4" href="#SEC4">PCRE NATIVE API INDIRECTED FUNCTIONS</a>
+<li><a name="TOC5" href="#SEC5">PCRE 8-BIT, 16-BIT, AND 32-BIT LIBRARIES</a>
+<li><a name="TOC6" href="#SEC6">PCRE API OVERVIEW</a>
+<li><a name="TOC7" href="#SEC7">NEWLINES</a>
+<li><a name="TOC8" href="#SEC8">MULTITHREADING</a>
+<li><a name="TOC9" href="#SEC9">SAVING PRECOMPILED PATTERNS FOR LATER USE</a>
+<li><a name="TOC10" href="#SEC10">CHECKING BUILD-TIME OPTIONS</a>
+<li><a name="TOC11" href="#SEC11">COMPILING A PATTERN</a>
+<li><a name="TOC12" href="#SEC12">COMPILATION ERROR CODES</a>
+<li><a name="TOC13" href="#SEC13">STUDYING A PATTERN</a>
+<li><a name="TOC14" href="#SEC14">LOCALE SUPPORT</a>
+<li><a name="TOC15" href="#SEC15">INFORMATION ABOUT A PATTERN</a>
+<li><a name="TOC16" href="#SEC16">REFERENCE COUNTS</a>
+<li><a name="TOC17" href="#SEC17">MATCHING A PATTERN: THE TRADITIONAL FUNCTION</a>
+<li><a name="TOC18" href="#SEC18">EXTRACTING CAPTURED SUBSTRINGS BY NUMBER</a>
+<li><a name="TOC19" href="#SEC19">EXTRACTING CAPTURED SUBSTRINGS BY NAME</a>
+<li><a name="TOC20" href="#SEC20">DUPLICATE SUBPATTERN NAMES</a>
+<li><a name="TOC21" href="#SEC21">FINDING ALL POSSIBLE MATCHES</a>
+<li><a name="TOC22" href="#SEC22">OBTAINING AN ESTIMATE OF STACK USAGE</a>
+<li><a name="TOC23" href="#SEC23">MATCHING A PATTERN: THE ALTERNATIVE FUNCTION</a>
+<li><a name="TOC24" href="#SEC24">SEE ALSO</a>
+<li><a name="TOC25" href="#SEC25">AUTHOR</a>
+<li><a name="TOC26" href="#SEC26">REVISION</a>
+</ul>
+<P>
+<b>#include &#60;pcre.h&#62;</b>
+</P>
+<br><a name="SEC1" href="#TOC1">PCRE NATIVE API BASIC FUNCTIONS</a><br>
+<P>
+<b>pcre *pcre_compile(const char *<i>pattern</i>, int <i>options</i>,</b>
+<b>     const char **<i>errptr</i>, int *<i>erroffset</i>,</b>
+<b>     const unsigned char *<i>tableptr</i>);</b>
+<br>
+<br>
+<b>pcre *pcre_compile2(const char *<i>pattern</i>, int <i>options</i>,</b>
+<b>     int *<i>errorcodeptr</i>,</b>
+<b>     const char **<i>errptr</i>, int *<i>erroffset</i>,</b>
+<b>     const unsigned char *<i>tableptr</i>);</b>
+<br>
+<br>
+<b>pcre_extra *pcre_study(const pcre *<i>code</i>, int <i>options</i>,</b>
+<b>     const char **<i>errptr</i>);</b>
+<br>
+<br>
+<b>void pcre_free_study(pcre_extra *<i>extra</i>);</b>
+<br>
+<br>
+<b>int pcre_exec(const pcre *<i>code</i>, const pcre_extra *<i>extra</i>,</b>
+<b>     const char *<i>subject</i>, int <i>length</i>, int <i>startoffset</i>,</b>
+<b>     int <i>options</i>, int *<i>ovector</i>, int <i>ovecsize</i>);</b>
+<br>
+<br>
+<b>int pcre_dfa_exec(const pcre *<i>code</i>, const pcre_extra *<i>extra</i>,</b>
+<b>     const char *<i>subject</i>, int <i>length</i>, int <i>startoffset</i>,</b>
+<b>     int <i>options</i>, int *<i>ovector</i>, int <i>ovecsize</i>,</b>
+<b>     int *<i>workspace</i>, int <i>wscount</i>);</b>
+</P>
+<br><a name="SEC2" href="#TOC1">PCRE NATIVE API STRING EXTRACTION FUNCTIONS</a><br>
+<P>
+<b>int pcre_copy_named_substring(const pcre *<i>code</i>,</b>
+<b>     const char *<i>subject</i>, int *<i>ovector</i>,</b>
+<b>     int <i>stringcount</i>, const char *<i>stringname</i>,</b>
+<b>     char *<i>buffer</i>, int <i>buffersize</i>);</b>
+<br>
+<br>
+<b>int pcre_copy_substring(const char *<i>subject</i>, int *<i>ovector</i>,</b>
+<b>     int <i>stringcount</i>, int <i>stringnumber</i>, char *<i>buffer</i>,</b>
+<b>     int <i>buffersize</i>);</b>
+<br>
+<br>
+<b>int pcre_get_named_substring(const pcre *<i>code</i>,</b>
+<b>     const char *<i>subject</i>, int *<i>ovector</i>,</b>
+<b>     int <i>stringcount</i>, const char *<i>stringname</i>,</b>
+<b>     const char **<i>stringptr</i>);</b>
+<br>
+<br>
+<b>int pcre_get_stringnumber(const pcre *<i>code</i>,</b>
+<b>     const char *<i>name</i>);</b>
+<br>
+<br>
+<b>int pcre_get_stringtable_entries(const pcre *<i>code</i>,</b>
+<b>     const char *<i>name</i>, char **<i>first</i>, char **<i>last</i>);</b>
+<br>
+<br>
+<b>int pcre_get_substring(const char *<i>subject</i>, int *<i>ovector</i>,</b>
+<b>     int <i>stringcount</i>, int <i>stringnumber</i>,</b>
+<b>     const char **<i>stringptr</i>);</b>
+<br>
+<br>
+<b>int pcre_get_substring_list(const char *<i>subject</i>,</b>
+<b>     int *<i>ovector</i>, int <i>stringcount</i>, const char ***<i>listptr</i>);</b>
+<br>
+<br>
+<b>void pcre_free_substring(const char *<i>stringptr</i>);</b>
+<br>
+<br>
+<b>void pcre_free_substring_list(const char **<i>stringptr</i>);</b>
+</P>
+<br><a name="SEC3" href="#TOC1">PCRE NATIVE API AUXILIARY FUNCTIONS</a><br>
+<P>
+<b>int pcre_jit_exec(const pcre *<i>code</i>, const pcre_extra *<i>extra</i>,</b>
+<b>     const char *<i>subject</i>, int <i>length</i>, int <i>startoffset</i>,</b>
+<b>     int <i>options</i>, int *<i>ovector</i>, int <i>ovecsize</i>,</b>
+<b>     pcre_jit_stack *<i>jstack</i>);</b>
+<br>
+<br>
+<b>pcre_jit_stack *pcre_jit_stack_alloc(int <i>startsize</i>, int <i>maxsize</i>);</b>
+<br>
+<br>
+<b>void pcre_jit_stack_free(pcre_jit_stack *<i>stack</i>);</b>
+<br>
+<br>
+<b>void pcre_assign_jit_stack(pcre_extra *<i>extra</i>,</b>
+<b>     pcre_jit_callback <i>callback</i>, void *<i>data</i>);</b>
+<br>
+<br>
+<b>const unsigned char *pcre_maketables(void);</b>
+<br>
+<br>
+<b>int pcre_fullinfo(const pcre *<i>code</i>, const pcre_extra *<i>extra</i>,</b>
+<b>     int <i>what</i>, void *<i>where</i>);</b>
+<br>
+<br>
+<b>int pcre_refcount(pcre *<i>code</i>, int <i>adjust</i>);</b>
+<br>
+<br>
+<b>int pcre_config(int <i>what</i>, void *<i>where</i>);</b>
+<br>
+<br>
+<b>const char *pcre_version(void);</b>
+<br>
+<br>
+<b>int pcre_pattern_to_host_byte_order(pcre *<i>code</i>,</b>
+<b>     pcre_extra *<i>extra</i>, const unsigned char *<i>tables</i>);</b>
+</P>
+<br><a name="SEC4" href="#TOC1">PCRE NATIVE API INDIRECTED FUNCTIONS</a><br>
+<P>
+<b>void *(*pcre_malloc)(size_t);</b>
+<br>
+<br>
+<b>void (*pcre_free)(void *);</b>
+<br>
+<br>
+<b>void *(*pcre_stack_malloc)(size_t);</b>
+<br>
+<br>
+<b>void (*pcre_stack_free)(void *);</b>
+<br>
+<br>
+<b>int (*pcre_callout)(pcre_callout_block *);</b>
+<br>
+<br>
+<b>int (*pcre_stack_guard)(void);</b>
+</P>
+<br><a name="SEC5" href="#TOC1">PCRE 8-BIT, 16-BIT, AND 32-BIT LIBRARIES</a><br>
+<P>
+As well as support for 8-bit character strings, PCRE also supports 16-bit
+strings (from release 8.30) and 32-bit strings (from release 8.32), by means of
+two additional libraries. They can be built as well as, or instead of, the
+8-bit library. To avoid too much complication, this document describes the
+8-bit versions of the functions, with only occasional references to the 16-bit
+and 32-bit libraries.
+</P>
+<P>
+The 16-bit and 32-bit functions operate in the same way as their 8-bit
+counterparts; they just use different data types for their arguments and
+results, and their names start with <b>pcre16_</b> or <b>pcre32_</b> instead of
+<b>pcre_</b>. For every option that has UTF8 in its name (for example,
+PCRE_UTF8), there are corresponding 16-bit and 32-bit names with UTF8 replaced
+by UTF16 or UTF32, respectively. This facility is in fact just cosmetic; the
+16-bit and 32-bit option names define the same bit values.
+</P>
+<P>
+References to bytes and UTF-8 in this document should be read as references to
+16-bit data units and UTF-16 when using the 16-bit library, or 32-bit data
+units and UTF-32 when using the 32-bit library, unless specified otherwise.
+More details of the specific differences for the 16-bit and 32-bit libraries
+are given in the
+<a href="pcre16.html"><b>pcre16</b></a>
+and
+<a href="pcre32.html"><b>pcre32</b></a>
+pages.
+</P>
+<br><a name="SEC6" href="#TOC1">PCRE API OVERVIEW</a><br>
+<P>
+PCRE has its own native API, which is described in this document. There are
+also some wrapper functions (for the 8-bit library only) that correspond to the
+POSIX regular expression API, but they do not give access to all the
+functionality. They are described in the
+<a href="pcreposix.html"><b>pcreposix</b></a>
+documentation. Both of these APIs define a set of C function calls. A C++
+wrapper (again for the 8-bit library only) is also distributed with PCRE. It is
+documented in the
+<a href="pcrecpp.html"><b>pcrecpp</b></a>
+page.
+</P>
+<P>
+The native API C function prototypes are defined in the header file
+<b>pcre.h</b>, and on Unix-like systems the (8-bit) library itself is called
+<b>libpcre</b>. It can normally be accessed by adding <b>-lpcre</b> to the
+command for linking an application that uses PCRE. The header file defines the
+macros PCRE_MAJOR and PCRE_MINOR to contain the major and minor release numbers
+for the library. Applications can use these to include support for different
+releases of PCRE.
+</P>
+<P>
+In a Windows environment, if you want to statically link an application program
+against a non-dll <b>pcre.a</b> file, you must define PCRE_STATIC before
+including <b>pcre.h</b> or <b>pcrecpp.h</b>, because otherwise the
+<b>pcre_malloc()</b> and <b>pcre_free()</b> exported functions will be declared
+<b>__declspec(dllimport)</b>, with unwanted results.
+</P>
+<P>
+The functions <b>pcre_compile()</b>, <b>pcre_compile2()</b>, <b>pcre_study()</b>,
+and <b>pcre_exec()</b> are used for compiling and matching regular expressions
+in a Perl-compatible manner. A sample program that demonstrates the simplest
+way of using them is provided in the file called <i>pcredemo.c</i> in the PCRE
+source distribution. A listing of this program is given in the
+<a href="pcredemo.html"><b>pcredemo</b></a>
+documentation, and the
+<a href="pcresample.html"><b>pcresample</b></a>
+documentation describes how to compile and run it.
+</P>
+<P>
+Just-in-time compiler support is an optional feature of PCRE that can be built
+in appropriate hardware environments. It greatly speeds up the matching
+performance of many patterns. Simple programs can easily request that it be
+used if available, by setting an option that is ignored when it is not
+relevant. More complicated programs might need to make use of the functions
+<b>pcre_jit_stack_alloc()</b>, <b>pcre_jit_stack_free()</b>, and
+<b>pcre_assign_jit_stack()</b> in order to control the JIT code's memory usage.
+</P>
+<P>
+From release 8.32 there is also a direct interface for JIT execution, which
+gives improved performance. The JIT-specific functions are discussed in the
+<a href="pcrejit.html"><b>pcrejit</b></a>
+documentation.
+</P>
+<P>
+A second matching function, <b>pcre_dfa_exec()</b>, which is not
+Perl-compatible, is also provided. This uses a different algorithm for the
+matching. The alternative algorithm finds all possible matches (at a given
+point in the subject), and scans the subject just once (unless there are
+lookbehind assertions). However, this algorithm does not return captured
+substrings. A description of the two matching algorithms and their advantages
+and disadvantages is given in the
+<a href="pcrematching.html"><b>pcrematching</b></a>
+documentation.
+</P>
+<P>
+In addition to the main compiling and matching functions, there are convenience
+functions for extracting captured substrings from a subject string that is
+matched by <b>pcre_exec()</b>. They are:
+<pre>
+  <b>pcre_copy_substring()</b>
+  <b>pcre_copy_named_substring()</b>
+  <b>pcre_get_substring()</b>
+  <b>pcre_get_named_substring()</b>
+  <b>pcre_get_substring_list()</b>
+  <b>pcre_get_stringnumber()</b>
+  <b>pcre_get_stringtable_entries()</b>
+</pre>
+<b>pcre_free_substring()</b> and <b>pcre_free_substring_list()</b> are also
+provided, to free the memory used for extracted strings.
+</P>
+<P>
+The function <b>pcre_maketables()</b> is used to build a set of character tables
+in the current locale for passing to <b>pcre_compile()</b>, <b>pcre_exec()</b>,
+or <b>pcre_dfa_exec()</b>. This is an optional facility that is provided for
+specialist use. Most commonly, no special tables are passed, in which case
+internal tables that are generated when PCRE is built are used.
+</P>
+<P>
+The function <b>pcre_fullinfo()</b> is used to find out information about a
+compiled pattern. The function <b>pcre_version()</b> returns a pointer to a
+string containing the version of PCRE and its date of release.
+</P>
+<P>
+The function <b>pcre_refcount()</b> maintains a reference count in a data block
+containing a compiled pattern. This is provided for the benefit of
+object-oriented applications.
+</P>
+<P>
+The global variables <b>pcre_malloc</b> and <b>pcre_free</b> initially contain
+the entry points of the standard <b>malloc()</b> and <b>free()</b> functions,
+respectively. PCRE calls the memory management functions via these variables,
+so a calling program can replace them if it wishes to intercept the calls. This
+should be done before calling any PCRE functions.
+</P>
+<P>
+The global variables <b>pcre_stack_malloc</b> and <b>pcre_stack_free</b> are also
+indirections to memory management functions. These special functions are used
+only when PCRE is compiled to use the heap for remembering data, instead of
+recursive function calls, when running the <b>pcre_exec()</b> function. See the
+<a href="pcrebuild.html"><b>pcrebuild</b></a>
+documentation for details of how to do this. It is a non-standard way of
+building PCRE, for use in environments that have limited stacks. Because of the
+greater use of memory management, it runs more slowly. Separate functions are
+provided so that special-purpose external code can be used for this case. When
+used, these functions are always called in a stack-like manner (last obtained,
+first freed), and always for memory blocks of the same size. There is a
+discussion about PCRE's stack usage in the
+<a href="pcrestack.html"><b>pcrestack</b></a>
+documentation.
+</P>
+<P>
+The global variable <b>pcre_callout</b> initially contains NULL. It can be set
+by the caller to a "callout" function, which PCRE will then call at specified
+points during a matching operation. Details are given in the
+<a href="pcrecallout.html"><b>pcrecallout</b></a>
+documentation.
+</P>
+<P>
+The global variable <b>pcre_stack_guard</b> initially contains NULL. It can be
+set by the caller to a function that is called by PCRE whenever it starts
+to compile a parenthesized part of a pattern. When parentheses are nested, PCRE
+uses recursive function calls, which use up the system stack. This function is
+provided so that applications with restricted stacks can force a compilation
+error if the stack runs out. The function should return zero if all is well, or
+non-zero to force an error.
+<a name="newlines"></a></P>
+<br><a name="SEC7" href="#TOC1">NEWLINES</a><br>
+<P>
+PCRE supports five different conventions for indicating line breaks in
+strings: a single CR (carriage return) character, a single LF (linefeed)
+character, the two-character sequence CRLF, any of the three preceding, or any
+Unicode newline sequence. The Unicode newline sequences are the three just
+mentioned, plus the single characters VT (vertical tab, U+000B), FF (form feed,
+U+000C), NEL (next line, U+0085), LS (line separator, U+2028), and PS
+(paragraph separator, U+2029).
+</P>
+<P>
+Each of the first three conventions is used by at least one operating system as
+its standard newline sequence. When PCRE is built, a default can be specified.
+The default default is LF, which is the Unix standard. When PCRE is run, the
+default can be overridden, either when a pattern is compiled, or when it is
+matched.
+</P>
+<P>
+At compile time, the newline convention can be specified by the <i>options</i>
+argument of <b>pcre_compile()</b>, or it can be specified by special text at the
+start of the pattern itself; this overrides any other settings. See the
+<a href="pcrepattern.html"><b>pcrepattern</b></a>
+page for details of the special character sequences.
+</P>
+<P>
+In the PCRE documentation the word "newline" is used to mean "the character or
+pair of characters that indicate a line break". The choice of newline
+convention affects the handling of the dot, circumflex, and dollar
+metacharacters, the handling of #-comments in /x mode, and, when CRLF is a
+recognized line ending sequence, the match position advancement for a
+non-anchored pattern. There is more detail about this in the
+<a href="#execoptions">section on <b>pcre_exec()</b> options</a>
+below.
+</P>
+<P>
+The choice of newline convention does not affect the interpretation of
+the \n or \r escape sequences, nor does it affect what \R matches, which is
+controlled in a similar way, but by separate options.
+</P>
+<br><a name="SEC8" href="#TOC1">MULTITHREADING</a><br>
+<P>
+The PCRE functions can be used in multi-threading applications, with the
+proviso that the memory management functions pointed to by <b>pcre_malloc</b>,
+<b>pcre_free</b>, <b>pcre_stack_malloc</b>, and <b>pcre_stack_free</b>, and the
+callout and stack-checking functions pointed to by <b>pcre_callout</b> and
+<b>pcre_stack_guard</b>, are shared by all threads.
+</P>
+<P>
+The compiled form of a regular expression is not altered during matching, so
+the same compiled pattern can safely be used by several threads at once.
+</P>
+<P>
+If the just-in-time optimization feature is being used, it needs separate
+memory stack areas for each thread. See the
+<a href="pcrejit.html"><b>pcrejit</b></a>
+documentation for more details.
+</P>
+<br><a name="SEC9" href="#TOC1">SAVING PRECOMPILED PATTERNS FOR LATER USE</a><br>
+<P>
+The compiled form of a regular expression can be saved and re-used at a later
+time, possibly by a different program, and even on a host other than the one on
+which it was compiled. Details are given in the
+<a href="pcreprecompile.html"><b>pcreprecompile</b></a>
+documentation, which includes a description of the
+<b>pcre_pattern_to_host_byte_order()</b> function. However, compiling a regular
+expression with one version of PCRE for use with a different version is not
+guaranteed to work and may cause crashes.
+</P>
+<br><a name="SEC10" href="#TOC1">CHECKING BUILD-TIME OPTIONS</a><br>
+<P>
+<b>int pcre_config(int <i>what</i>, void *<i>where</i>);</b>
+</P>
+<P>
+The function <b>pcre_config()</b> makes it possible for a PCRE client to
+discover which optional features have been compiled into the PCRE library. The
+<a href="pcrebuild.html"><b>pcrebuild</b></a>
+documentation has more details about these optional features.
+</P>
+<P>
+The first argument for <b>pcre_config()</b> is an integer, specifying which
+information is required; the second argument is a pointer to a variable into
+which the information is placed. The returned value is zero on success, or the
+negative error code PCRE_ERROR_BADOPTION if the value in the first argument is
+not recognized. The following information is available:
+<pre>
+  PCRE_CONFIG_UTF8
+</pre>
+The output is an integer that is set to one if UTF-8 support is available;
+otherwise it is set to zero. This value should normally be given to the 8-bit
+version of this function, <b>pcre_config()</b>. If it is given to the 16-bit
+or 32-bit version of this function, the result is PCRE_ERROR_BADOPTION.
+<pre>
+  PCRE_CONFIG_UTF16
+</pre>
+The output is an integer that is set to one if UTF-16 support is available;
+otherwise it is set to zero. This value should normally be given to the 16-bit
+version of this function, <b>pcre16_config()</b>. If it is given to the 8-bit
+or 32-bit version of this function, the result is PCRE_ERROR_BADOPTION.
+<pre>
+  PCRE_CONFIG_UTF32
+</pre>
+The output is an integer that is set to one if UTF-32 support is available;
+otherwise it is set to zero. This value should normally be given to the 32-bit
+version of this function, <b>pcre32_config()</b>. If it is given to the 8-bit
+or 16-bit version of this function, the result is PCRE_ERROR_BADOPTION.
+<pre>
+  PCRE_CONFIG_UNICODE_PROPERTIES
+</pre>
+The output is an integer that is set to one if support for Unicode character
+properties is available; otherwise it is set to zero.
+<pre>
+  PCRE_CONFIG_JIT
+</pre>
+The output is an integer that is set to one if support for just-in-time
+compiling is available; otherwise it is set to zero.
+<pre>
+  PCRE_CONFIG_JITTARGET
+</pre>
+The output is a pointer to a zero-terminated "const char *" string. If JIT
+support is available, the string contains the name of the architecture for
+which the JIT compiler is configured, for example "x86 32bit (little endian +
+unaligned)". If JIT support is not available, the result is NULL.
+<pre>
+  PCRE_CONFIG_NEWLINE
+</pre>
+The output is an integer whose value specifies the default character sequence
+that is recognized as meaning "newline". The values that are supported in
+ASCII/Unicode environments are: 10 for LF, 13 for CR, 3338 for CRLF, -2 for
+ANYCRLF, and -1 for ANY. In EBCDIC environments, CR, ANYCRLF, and ANY yield the
+same values. However, the value for LF is normally 21, though some EBCDIC
+environments use 37. The corresponding values for CRLF are 3349 and 3365. The
+default should normally correspond to the standard sequence for your operating
+system.
+<pre>
+  PCRE_CONFIG_BSR
+</pre>
+The output is an integer whose value indicates what character sequences the \R
+escape sequence matches by default. A value of 0 means that \R matches any
+Unicode line ending sequence; a value of 1 means that \R matches only CR, LF,
+or CRLF. The default can be overridden when a pattern is compiled or matched.
+<pre>
+  PCRE_CONFIG_LINK_SIZE
+</pre>
+The output is an integer that contains the number of bytes used for internal
+linkage in compiled regular expressions. For the 8-bit library, the value can
+be 2, 3, or 4. For the 16-bit library, the value is either 2 or 4 and is still
+a number of bytes. For the 32-bit library, the value is either 2 or 4 and is
+still a number of bytes. The default value of 2 is sufficient for all but the
+most massive patterns, since it allows the compiled pattern to be up to 64K in
+size. Larger values allow larger regular expressions to be compiled, at the
+expense of slower matching.
+<pre>
+  PCRE_CONFIG_POSIX_MALLOC_THRESHOLD
+</pre>
+The output is an integer that contains the threshold above which the POSIX
+interface uses <b>malloc()</b> for output vectors. Further details are given in
+the
+<a href="pcreposix.html"><b>pcreposix</b></a>
+documentation.
+<pre>
+  PCRE_CONFIG_PARENS_LIMIT
+</pre>
+The output is a long integer that gives the maximum depth of nesting of
+parentheses (of any kind) in a pattern. This limit is imposed to cap the amount
+of system stack used when a pattern is compiled. It is specified when PCRE is
+built; the default is 250. This limit does not take into account the stack that
+may already be used by the calling application. For finer control over
+compilation stack usage, you can set a pointer to an external checking function
+in <b>pcre_stack_guard</b>.
+<pre>
+  PCRE_CONFIG_MATCH_LIMIT
+</pre>
+The output is a long integer that gives the default limit for the number of
+internal matching function calls in a <b>pcre_exec()</b> execution. Further
+details are given with <b>pcre_exec()</b> below.
+<pre>
+  PCRE_CONFIG_MATCH_LIMIT_RECURSION
+</pre>
+The output is a long integer that gives the default limit for the depth of
+recursion when calling the internal matching function in a <b>pcre_exec()</b>
+execution. Further details are given with <b>pcre_exec()</b> below.
+<pre>
+  PCRE_CONFIG_STACKRECURSE
+</pre>
+The output is an integer that is set to one if internal recursion when running
+<b>pcre_exec()</b> is implemented by recursive function calls that use the stack
+to remember their state. This is the usual way that PCRE is compiled. The
+output is zero if PCRE was compiled to use blocks of data on the heap instead
+of recursive function calls. In this case, <b>pcre_stack_malloc</b> and
+<b>pcre_stack_free</b> are called to manage memory blocks on the heap, thus
+avoiding the use of the stack.
+</P>
+<br><a name="SEC11" href="#TOC1">COMPILING A PATTERN</a><br>
+<P>
+<b>pcre *pcre_compile(const char *<i>pattern</i>, int <i>options</i>,</b>
+<b>     const char **<i>errptr</i>, int *<i>erroffset</i>,</b>
+<b>     const unsigned char *<i>tableptr</i>);</b>
+<br>
+<br>
+<b>pcre *pcre_compile2(const char *<i>pattern</i>, int <i>options</i>,</b>
+<b>     int *<i>errorcodeptr</i>,</b>
+<b>     const char **<i>errptr</i>, int *<i>erroffset</i>,</b>
+<b>     const unsigned char *<i>tableptr</i>);</b>
+</P>
+<P>
+Either of the functions <b>pcre_compile()</b> or <b>pcre_compile2()</b> can be
+called to compile a pattern into an internal form. The only difference between
+the two interfaces is that <b>pcre_compile2()</b> has an additional argument,
+<i>errorcodeptr</i>, via which a numerical error code can be returned. To avoid
+too much repetition, we refer just to <b>pcre_compile()</b> below, but the
+information applies equally to <b>pcre_compile2()</b>.
+</P>
+<P>
+The pattern is a C string terminated by a binary zero, and is passed in the
+<i>pattern</i> argument. A pointer to a single block of memory that is obtained
+via <b>pcre_malloc</b> is returned. This contains the compiled code and related
+data. The <b>pcre</b> type is defined for the returned block; this is a typedef
+for a structure whose contents are not externally defined. It is up to the
+caller to free the memory (via <b>pcre_free</b>) when it is no longer required.
+</P>
+<P>
+Although the compiled code of a PCRE regex is relocatable, that is, it does not
+depend on memory location, the complete <b>pcre</b> data block is not
+fully relocatable, because it may contain a copy of the <i>tableptr</i>
+argument, which is an address (see below).
+</P>
+<P>
+The <i>options</i> argument contains various bit settings that affect the
+compilation. It should be zero if no options are required. The available
+options are described below. Some of them (in particular, those that are
+compatible with Perl, but some others as well) can also be set and unset from
+within the pattern (see the detailed description in the
+<a href="pcrepattern.html"><b>pcrepattern</b></a>
+documentation). For those options that can be different in different parts of
+the pattern, the contents of the <i>options</i> argument specifies their
+settings at the start of compilation and execution. The PCRE_ANCHORED,
+PCRE_BSR_<i>xxx</i>, PCRE_NEWLINE_<i>xxx</i>, PCRE_NO_UTF8_CHECK, and
+PCRE_NO_START_OPTIMIZE options can be set at the time of matching as well as at
+compile time.
+</P>
+<P>
+If <i>errptr</i> is NULL, <b>pcre_compile()</b> returns NULL immediately.
+Otherwise, if compilation of a pattern fails, <b>pcre_compile()</b> returns
+NULL, and sets the variable pointed to by <i>errptr</i> to point to a textual
+error message. This is a static string that is part of the library. You must
+not try to free it. Normally, the offset from the start of the pattern to the
+data unit that was being processed when the error was discovered is placed in
+the variable pointed to by <i>erroffset</i>, which must not be NULL (if it is,
+an immediate error is given). However, for an invalid UTF-8 or UTF-16 string,
+the offset is that of the first data unit of the failing character.
+</P>
+<P>
+Some errors are not detected until the whole pattern has been scanned; in these
+cases, the offset passed back is the length of the pattern. Note that the
+offset is in data units, not characters, even in a UTF mode. It may sometimes
+point into the middle of a UTF-8 or UTF-16 character.
+</P>
+<P>
+If <b>pcre_compile2()</b> is used instead of <b>pcre_compile()</b>, and the
+<i>errorcodeptr</i> argument is not NULL, a non-zero error code number is
+returned via this argument in the event of an error. This is in addition to the
+textual error message. Error codes and messages are listed below.
+</P>
+<P>
+If the final argument, <i>tableptr</i>, is NULL, PCRE uses a default set of
+character tables that are built when PCRE is compiled, using the default C
+locale. Otherwise, <i>tableptr</i> must be an address that is the result of a
+call to <b>pcre_maketables()</b>. This value is stored with the compiled
+pattern, and used again by <b>pcre_exec()</b> and <b>pcre_dfa_exec()</b> when the
+pattern is matched. For more discussion, see the section on locale support
+below.
+</P>
+<P>
+This code fragment shows a typical straightforward call to <b>pcre_compile()</b>:
+<pre>
+  pcre *re;
+  const char *error;
+  int erroffset;
+  re = pcre_compile(
+    "^A.*Z",          /* the pattern */
+    0,                /* default options */
+    &error,           /* for error message */
+    &erroffset,       /* for error offset */
+    NULL);            /* use default character tables */
+</pre>
+The following names for option bits are defined in the <b>pcre.h</b> header
+file:
+<pre>
+  PCRE_ANCHORED
+</pre>
+If this bit is set, the pattern is forced to be "anchored", that is, it is
+constrained to match only at the first matching point in the string that is
+being searched (the "subject string"). This effect can also be achieved by
+appropriate constructs in the pattern itself, which is the only way to do it in
+Perl.
+<pre>
+  PCRE_AUTO_CALLOUT
+</pre>
+If this bit is set, <b>pcre_compile()</b> automatically inserts callout items,
+all with number 255, before each pattern item. For discussion of the callout
+facility, see the
+<a href="pcrecallout.html"><b>pcrecallout</b></a>
+documentation.
+<pre>
+  PCRE_BSR_ANYCRLF
+  PCRE_BSR_UNICODE
+</pre>
+These options (which are mutually exclusive) control what the \R escape
+sequence matches. The choice is either to match only CR, LF, or CRLF, or to
+match any Unicode newline sequence. The default is specified when PCRE is
+built. It can be overridden from within the pattern, or by setting an option
+when a compiled pattern is matched.
+<pre>
+  PCRE_CASELESS
+</pre>
+If this bit is set, letters in the pattern match both upper and lower case
+letters. It is equivalent to Perl's /i option, and it can be changed within a
+pattern by a (?i) option setting. In UTF-8 mode, PCRE always understands the
+concept of case for characters whose values are less than 128, so caseless
+matching is always possible. For characters with higher values, the concept of
+case is supported if PCRE is compiled with Unicode property support, but not
+otherwise. If you want to use caseless matching for characters 128 and above,
+you must ensure that PCRE is compiled with Unicode property support as well as
+with UTF-8 support.
+<pre>
+  PCRE_DOLLAR_ENDONLY
+</pre>
+If this bit is set, a dollar metacharacter in the pattern matches only at the
+end of the subject string. Without this option, a dollar also matches
+immediately before a newline at the end of the string (but not before any other
+newlines). The PCRE_DOLLAR_ENDONLY option is ignored if PCRE_MULTILINE is set.
+There is no equivalent to this option in Perl, and no way to set it within a
+pattern.
+<pre>
+  PCRE_DOTALL
+</pre>
+If this bit is set, a dot metacharacter in the pattern matches a character of
+any value, including one that indicates a newline. However, it only ever
+matches one character, even if newlines are coded as CRLF. Without this option,
+a dot does not match when the current position is at a newline. This option is
+equivalent to Perl's /s option, and it can be changed within a pattern by a
+(?s) option setting. A negative class such as [^a] always matches newline
+characters, independent of the setting of this option.
+<pre>
+  PCRE_DUPNAMES
+</pre>
+If this bit is set, names used to identify capturing subpatterns need not be
+unique. This can be helpful for certain types of pattern when it is known that
+only one instance of the named subpattern can ever be matched. There are more
+details of named subpatterns below; see also the
+<a href="pcrepattern.html"><b>pcrepattern</b></a>
+documentation.
+<pre>
+  PCRE_EXTENDED
+</pre>
+If this bit is set, most white space characters in the pattern are totally
+ignored except when escaped or inside a character class. However, white space
+is not allowed within sequences such as (?&#62; that introduce various
+parenthesized subpatterns, nor within a numerical quantifier such as {1,3}.
+However, ignorable white space is permitted between an item and a following
+quantifier and between a quantifier and a following + that indicates
+possessiveness.
+</P>
+<P>
+White space did not used to include the VT character (code 11), because Perl
+did not treat this character as white space. However, Perl changed at release
+5.18, so PCRE followed at release 8.34, and VT is now treated as white space.
+</P>
+<P>
+PCRE_EXTENDED also causes characters between an unescaped # outside a character
+class and the next newline, inclusive, to be ignored. PCRE_EXTENDED is
+equivalent to Perl's /x option, and it can be changed within a pattern by a
+(?x) option setting.
+</P>
+<P>
+Which characters are interpreted as newlines is controlled by the options
+passed to <b>pcre_compile()</b> or by a special sequence at the start of the
+pattern, as described in the section entitled
+<a href="pcrepattern.html#newlines">"Newline conventions"</a>
+in the <b>pcrepattern</b> documentation. Note that the end of this type of
+comment is a literal newline sequence in the pattern; escape sequences that
+happen to represent a newline do not count.
+</P>
+<P>
+This option makes it possible to include comments inside complicated patterns.
+Note, however, that this applies only to data characters. White space characters
+may never appear within special character sequences in a pattern, for example
+within the sequence (?( that introduces a conditional subpattern.
+<pre>
+  PCRE_EXTRA
+</pre>
+This option was invented in order to turn on additional functionality of PCRE
+that is incompatible with Perl, but it is currently of very little use. When
+set, any backslash in a pattern that is followed by a letter that has no
+special meaning causes an error, thus reserving these combinations for future
+expansion. By default, as in Perl, a backslash followed by a letter with no
+special meaning is treated as a literal. (Perl can, however, be persuaded to
+give an error for this, by running it with the -w option.) There are at present
+no other features controlled by this option. It can also be set by a (?X)
+option setting within a pattern.
+<pre>
+  PCRE_FIRSTLINE
+</pre>
+If this option is set, an unanchored pattern is required to match before or at
+the first newline in the subject string, though the matched text may continue
+over the newline.
+<pre>
+  PCRE_JAVASCRIPT_COMPAT
+</pre>
+If this option is set, PCRE's behaviour is changed in some ways so that it is
+compatible with JavaScript rather than Perl. The changes are as follows:
+</P>
+<P>
+(1) A lone closing square bracket in a pattern causes a compile-time error,
+because this is illegal in JavaScript (by default it is treated as a data
+character). Thus, the pattern AB]CD becomes illegal when this option is set.
+</P>
+<P>
+(2) At run time, a back reference to an unset subpattern group matches an empty
+string (by default this causes the current matching alternative to fail). A
+pattern such as (\1)(a) succeeds when this option is set (assuming it can find
+an "a" in the subject), whereas it fails by default, for Perl compatibility.
+</P>
+<P>
+(3) \U matches an upper case "U" character; by default \U causes a compile
+time error (Perl uses \U to upper case subsequent characters).
+</P>
+<P>
+(4) \u matches a lower case "u" character unless it is followed by four
+hexadecimal digits, in which case the hexadecimal number defines the code point
+to match. By default, \u causes a compile time error (Perl uses it to upper
+case the following character).
+</P>
+<P>
+(5) \x matches a lower case "x" character unless it is followed by two
+hexadecimal digits, in which case the hexadecimal number defines the code point
+to match. By default, as in Perl, a hexadecimal number is always expected after
+\x, but it may have zero, one, or two digits (so, for example, \xz matches a
+binary zero character followed by z).
+<pre>
+  PCRE_MULTILINE
+</pre>
+By default, for the purposes of matching "start of line" and "end of line",
+PCRE treats the subject string as consisting of a single line of characters,
+even if it actually contains newlines. The "start of line" metacharacter (^)
+matches only at the start of the string, and the "end of line" metacharacter
+($) matches only at the end of the string, or before a terminating newline
+(except when PCRE_DOLLAR_ENDONLY is set). Note, however, that unless
+PCRE_DOTALL is set, the "any character" metacharacter (.) does not match at a
+newline. This behaviour (for ^, $, and dot) is the same as Perl.
+</P>
+<P>
+When PCRE_MULTILINE it is set, the "start of line" and "end of line" constructs
+match immediately following or immediately before internal newlines in the
+subject string, respectively, as well as at the very start and end. This is
+equivalent to Perl's /m option, and it can be changed within a pattern by a
+(?m) option setting. If there are no newlines in a subject string, or no
+occurrences of ^ or $ in a pattern, setting PCRE_MULTILINE has no effect.
+<pre>
+  PCRE_NEVER_UTF
+</pre>
+This option locks out interpretation of the pattern as UTF-8 (or UTF-16 or
+UTF-32 in the 16-bit and 32-bit libraries). In particular, it prevents the
+creator of the pattern from switching to UTF interpretation by starting the
+pattern with (*UTF). This may be useful in applications that process patterns
+from external sources. The combination of PCRE_UTF8 and PCRE_NEVER_UTF also
+causes an error.
+<pre>
+  PCRE_NEWLINE_CR
+  PCRE_NEWLINE_LF
+  PCRE_NEWLINE_CRLF
+  PCRE_NEWLINE_ANYCRLF
+  PCRE_NEWLINE_ANY
+</pre>
+These options override the default newline definition that was chosen when PCRE
+was built. Setting the first or the second specifies that a newline is
+indicated by a single character (CR or LF, respectively). Setting
+PCRE_NEWLINE_CRLF specifies that a newline is indicated by the two-character
+CRLF sequence. Setting PCRE_NEWLINE_ANYCRLF specifies that any of the three
+preceding sequences should be recognized. Setting PCRE_NEWLINE_ANY specifies
+that any Unicode newline sequence should be recognized.
+</P>
+<P>
+In an ASCII/Unicode environment, the Unicode newline sequences are the three
+just mentioned, plus the single characters VT (vertical tab, U+000B), FF (form
+feed, U+000C), NEL (next line, U+0085), LS (line separator, U+2028), and PS
+(paragraph separator, U+2029). For the 8-bit library, the last two are
+recognized only in UTF-8 mode.
+</P>
+<P>
+When PCRE is compiled to run in an EBCDIC (mainframe) environment, the code for
+CR is 0x0d, the same as ASCII. However, the character code for LF is normally
+0x15, though in some EBCDIC environments 0x25 is used. Whichever of these is
+not LF is made to correspond to Unicode's NEL character. EBCDIC codes are all
+less than 256. For more details, see the
+<a href="pcrebuild.html"><b>pcrebuild</b></a>
+documentation.
+</P>
+<P>
+The newline setting in the options word uses three bits that are treated
+as a number, giving eight possibilities. Currently only six are used (default
+plus the five values above). This means that if you set more than one newline
+option, the combination may or may not be sensible. For example,
+PCRE_NEWLINE_CR with PCRE_NEWLINE_LF is equivalent to PCRE_NEWLINE_CRLF, but
+other combinations may yield unused numbers and cause an error.
+</P>
+<P>
+The only time that a line break in a pattern is specially recognized when
+compiling is when PCRE_EXTENDED is set. CR and LF are white space characters,
+and so are ignored in this mode. Also, an unescaped # outside a character class
+indicates a comment that lasts until after the next line break sequence. In
+other circumstances, line break sequences in patterns are treated as literal
+data.
+</P>
+<P>
+The newline option that is set at compile time becomes the default that is used
+for <b>pcre_exec()</b> and <b>pcre_dfa_exec()</b>, but it can be overridden.
+<pre>
+  PCRE_NO_AUTO_CAPTURE
+</pre>
+If this option is set, it disables the use of numbered capturing parentheses in
+the pattern. Any opening parenthesis that is not followed by ? behaves as if it
+were followed by ?: but named parentheses can still be used for capturing (and
+they acquire numbers in the usual way). There is no equivalent of this option
+in Perl.
+<pre>
+  PCRE_NO_AUTO_POSSESS
+</pre>
+If this option is set, it disables "auto-possessification". This is an
+optimization that, for example, turns a+b into a++b in order to avoid
+backtracks into a+ that can never be successful. However, if callouts are in
+use, auto-possessification means that some of them are never taken. You can set
+this option if you want the matching functions to do a full unoptimized search
+and run all the callouts, but it is mainly provided for testing purposes.
+<pre>
+  PCRE_NO_START_OPTIMIZE
+</pre>
+This is an option that acts at matching time; that is, it is really an option
+for <b>pcre_exec()</b> or <b>pcre_dfa_exec()</b>. If it is set at compile time,
+it is remembered with the compiled pattern and assumed at matching time. This
+is necessary if you want to use JIT execution, because the JIT compiler needs
+to know whether or not this option is set. For details see the discussion of
+PCRE_NO_START_OPTIMIZE
+<a href="#execoptions">below.</a>
+<pre>
+  PCRE_UCP
+</pre>
+This option changes the way PCRE processes \B, \b, \D, \d, \S, \s, \W,
+\w, and some of the POSIX character classes. By default, only ASCII characters
+are recognized, but if PCRE_UCP is set, Unicode properties are used instead to
+classify characters. More details are given in the section on
+<a href="pcre.html#genericchartypes">generic character types</a>
+in the
+<a href="pcrepattern.html"><b>pcrepattern</b></a>
+page. If you set PCRE_UCP, matching one of the items it affects takes much
+longer. The option is available only if PCRE has been compiled with Unicode
+property support.
+<pre>
+  PCRE_UNGREEDY
+</pre>
+This option inverts the "greediness" of the quantifiers so that they are not
+greedy by default, but become greedy if followed by "?". It is not compatible
+with Perl. It can also be set by a (?U) option setting within the pattern.
+<pre>
+  PCRE_UTF8
+</pre>
+This option causes PCRE to regard both the pattern and the subject as strings
+of UTF-8 characters instead of single-byte strings. However, it is available
+only when PCRE is built to include UTF support. If not, the use of this option
+provokes an error. Details of how this option changes the behaviour of PCRE are
+given in the
+<a href="pcreunicode.html"><b>pcreunicode</b></a>
+page.
+<pre>
+  PCRE_NO_UTF8_CHECK
+</pre>
+When PCRE_UTF8 is set, the validity of the pattern as a UTF-8 string is
+automatically checked. There is a discussion about the
+<a href="pcreunicode.html#utf8strings">validity of UTF-8 strings</a>
+in the
+<a href="pcreunicode.html"><b>pcreunicode</b></a>
+page. If an invalid UTF-8 sequence is found, <b>pcre_compile()</b> returns an
+error. If you already know that your pattern is valid, and you want to skip
+this check for performance reasons, you can set the PCRE_NO_UTF8_CHECK option.
+When it is set, the effect of passing an invalid UTF-8 string as a pattern is
+undefined. It may cause your program to crash or loop. Note that this option
+can also be passed to <b>pcre_exec()</b> and <b>pcre_dfa_exec()</b>, to suppress
+the validity checking of subject strings only. If the same string is being
+matched many times, the option can be safely set for the second and subsequent
+matchings to improve performance.
+</P>
+<br><a name="SEC12" href="#TOC1">COMPILATION ERROR CODES</a><br>
+<P>
+The following table lists the error codes than may be returned by
+<b>pcre_compile2()</b>, along with the error messages that may be returned by
+both compiling functions. Note that error messages are always 8-bit ASCII
+strings, even in 16-bit or 32-bit mode. As PCRE has developed, some error codes
+have fallen out of use. To avoid confusion, they have not been re-used.
+<pre>
+   0  no error
+   1  \ at end of pattern
+   2  \c at end of pattern
+   3  unrecognized character follows \
+   4  numbers out of order in {} quantifier
+   5  number too big in {} quantifier
+   6  missing terminating ] for character class
+   7  invalid escape sequence in character class
+   8  range out of order in character class
+   9  nothing to repeat
+  10  [this code is not in use]
+  11  internal error: unexpected repeat
+  12  unrecognized character after (? or (?-
+  13  POSIX named classes are supported only within a class
+  14  missing )
+  15  reference to non-existent subpattern
+  16  erroffset passed as NULL
+  17  unknown option bit(s) set
+  18  missing ) after comment
+  19  [this code is not in use]
+  20  regular expression is too large
+  21  failed to get memory
+  22  unmatched parentheses
+  23  internal error: code overflow
+  24  unrecognized character after (?&#60;
+  25  lookbehind assertion is not fixed length
+  26  malformed number or name after (?(
+  27  conditional group contains more than two branches
+  28  assertion expected after (?(
+  29  (?R or (?[+-]digits must be followed by )
+  30  unknown POSIX class name
+  31  POSIX collating elements are not supported
+  32  this version of PCRE is compiled without UTF support
+  33  [this code is not in use]
+  34  character value in \x{} or \o{} is too large
+  35  invalid condition (?(0)
+  36  \C not allowed in lookbehind assertion
+  37  PCRE does not support \L, \l, \N{name}, \U, or \u
+  38  number after (?C is &#62; 255
+  39  closing ) for (?C expected
+  40  recursive call could loop indefinitely
+  41  unrecognized character after (?P
+  42  syntax error in subpattern name (missing terminator)
+  43  two named subpatterns have the same name
+  44  invalid UTF-8 string (specifically UTF-8)
+  45  support for \P, \p, and \X has not been compiled
+  46  malformed \P or \p sequence
+  47  unknown property name after \P or \p
+  48  subpattern name is too long (maximum 32 characters)
+  49  too many named subpatterns (maximum 10000)
+  50  [this code is not in use]
+  51  octal value is greater than \377 in 8-bit non-UTF-8 mode
+  52  internal error: overran compiling workspace
+  53  internal error: previously-checked referenced subpattern
+        not found
+  54  DEFINE group contains more than one branch
+  55  repeating a DEFINE group is not allowed
+  56  inconsistent NEWLINE options
+  57  \g is not followed by a braced, angle-bracketed, or quoted
+        name/number or by a plain number
+  58  a numbered reference must not be zero
+  59  an argument is not allowed for (*ACCEPT), (*FAIL), or (*COMMIT)
+  60  (*VERB) not recognized or malformed
+  61  number is too big
+  62  subpattern name expected
+  63  digit expected after (?+
+  64  ] is an invalid data character in JavaScript compatibility mode
+  65  different names for subpatterns of the same number are
+        not allowed
+  66  (*MARK) must have an argument
+  67  this version of PCRE is not compiled with Unicode property
+        support
+  68  \c must be followed by an ASCII character
+  69  \k is not followed by a braced, angle-bracketed, or quoted name
+  70  internal error: unknown opcode in find_fixedlength()
+  71  \N is not supported in a class
+  72  too many forward references
+  73  disallowed Unicode code point (&#62;= 0xd800 && &#60;= 0xdfff)
+  74  invalid UTF-16 string (specifically UTF-16)
+  75  name is too long in (*MARK), (*PRUNE), (*SKIP), or (*THEN)
+  76  character value in \u.... sequence is too large
+  77  invalid UTF-32 string (specifically UTF-32)
+  78  setting UTF is disabled by the application
+  79  non-hex character in \x{} (closing brace missing?)
+  80  non-octal character in \o{} (closing brace missing?)
+  81  missing opening brace after \o
+  82  parentheses are too deeply nested
+  83  invalid range in character class
+  84  group name must start with a non-digit
+  85  parentheses are too deeply nested (stack check)
+</pre>
+The numbers 32 and 10000 in errors 48 and 49 are defaults; different values may
+be used if the limits were changed when PCRE was built.
+<a name="studyingapattern"></a></P>
+<br><a name="SEC13" href="#TOC1">STUDYING A PATTERN</a><br>
+<P>
+<b>pcre_extra *pcre_study(const pcre *<i>code</i>, int <i>options</i>,</b>
+<b>     const char **<i>errptr</i>);</b>
+</P>
+<P>
+If a compiled pattern is going to be used several times, it is worth spending
+more time analyzing it in order to speed up the time taken for matching. The
+function <b>pcre_study()</b> takes a pointer to a compiled pattern as its first
+argument. If studying the pattern produces additional information that will
+help speed up matching, <b>pcre_study()</b> returns a pointer to a
+<b>pcre_extra</b> block, in which the <i>study_data</i> field points to the
+results of the study.
+</P>
+<P>
+The returned value from <b>pcre_study()</b> can be passed directly to
+<b>pcre_exec()</b> or <b>pcre_dfa_exec()</b>. However, a <b>pcre_extra</b> block
+also contains other fields that can be set by the caller before the block is
+passed; these are described
+<a href="#extradata">below</a>
+in the section on matching a pattern.
+</P>
+<P>
+If studying the pattern does not produce any useful information,
+<b>pcre_study()</b> returns NULL by default. In that circumstance, if the
+calling program wants to pass any of the other fields to <b>pcre_exec()</b> or
+<b>pcre_dfa_exec()</b>, it must set up its own <b>pcre_extra</b> block. However,
+if <b>pcre_study()</b> is called with the PCRE_STUDY_EXTRA_NEEDED option, it
+returns a <b>pcre_extra</b> block even if studying did not find any additional
+information. It may still return NULL, however, if an error occurs in
+<b>pcre_study()</b>.
+</P>
+<P>
+The second argument of <b>pcre_study()</b> contains option bits. There are three
+further options in addition to PCRE_STUDY_EXTRA_NEEDED:
+<pre>
+  PCRE_STUDY_JIT_COMPILE
+  PCRE_STUDY_JIT_PARTIAL_HARD_COMPILE
+  PCRE_STUDY_JIT_PARTIAL_SOFT_COMPILE
+</pre>
+If any of these are set, and the just-in-time compiler is available, the
+pattern is further compiled into machine code that executes much faster than
+the <b>pcre_exec()</b> interpretive matching function. If the just-in-time
+compiler is not available, these options are ignored. All undefined bits in the
+<i>options</i> argument must be zero.
+</P>
+<P>
+JIT compilation is a heavyweight optimization. It can take some time for
+patterns to be analyzed, and for one-off matches and simple patterns the
+benefit of faster execution might be offset by a much slower study time.
+Not all patterns can be optimized by the JIT compiler. For those that cannot be
+handled, matching automatically falls back to the <b>pcre_exec()</b>
+interpreter. For more details, see the
+<a href="pcrejit.html"><b>pcrejit</b></a>
+documentation.
+</P>
+<P>
+The third argument for <b>pcre_study()</b> is a pointer for an error message. If
+studying succeeds (even if no data is returned), the variable it points to is
+set to NULL. Otherwise it is set to point to a textual error message. This is a
+static string that is part of the library. You must not try to free it. You
+should test the error pointer for NULL after calling <b>pcre_study()</b>, to be
+sure that it has run successfully.
+</P>
+<P>
+When you are finished with a pattern, you can free the memory used for the
+study data by calling <b>pcre_free_study()</b>. This function was added to the
+API for release 8.20. For earlier versions, the memory could be freed with
+<b>pcre_free()</b>, just like the pattern itself. This will still work in cases
+where JIT optimization is not used, but it is advisable to change to the new
+function when convenient.
+</P>
+<P>
+This is a typical way in which <b>pcre_study</b>() is used (except that in a
+real application there should be tests for errors):
+<pre>
+  int rc;
+  pcre *re;
+  pcre_extra *sd;
+  re = pcre_compile("pattern", 0, &error, &erroroffset, NULL);
+  sd = pcre_study(
+    re,             /* result of pcre_compile() */
+    0,              /* no options */
+    &error);        /* set to NULL or points to a message */
+  rc = pcre_exec(   /* see below for details of pcre_exec() options */
+    re, sd, "subject", 7, 0, 0, ovector, 30);
+  ...
+  pcre_free_study(sd);
+  pcre_free(re);
+</pre>
+Studying a pattern does two things: first, a lower bound for the length of
+subject string that is needed to match the pattern is computed. This does not
+mean that there are any strings of that length that match, but it does
+guarantee that no shorter strings match. The value is used to avoid wasting
+time by trying to match strings that are shorter than the lower bound. You can
+find out the value in a calling program via the <b>pcre_fullinfo()</b> function.
+</P>
+<P>
+Studying a pattern is also useful for non-anchored patterns that do not have a
+single fixed starting character. A bitmap of possible starting bytes is
+created. This speeds up finding a position in the subject at which to start
+matching. (In 16-bit mode, the bitmap is used for 16-bit values less than 256.
+In 32-bit mode, the bitmap is used for 32-bit values less than 256.)
+</P>
+<P>
+These two optimizations apply to both <b>pcre_exec()</b> and
+<b>pcre_dfa_exec()</b>, and the information is also used by the JIT compiler.
+The optimizations can be disabled by setting the PCRE_NO_START_OPTIMIZE option.
+You might want to do this if your pattern contains callouts or (*MARK) and you
+want to make use of these facilities in cases where matching fails.
+</P>
+<P>
+PCRE_NO_START_OPTIMIZE can be specified at either compile time or execution
+time. However, if PCRE_NO_START_OPTIMIZE is passed to <b>pcre_exec()</b>, (that
+is, after any JIT compilation has happened) JIT execution is disabled. For JIT
+execution to work with PCRE_NO_START_OPTIMIZE, the option must be set at
+compile time.
+</P>
+<P>
+There is a longer discussion of PCRE_NO_START_OPTIMIZE
+<a href="#execoptions">below.</a>
+<a name="localesupport"></a></P>
+<br><a name="SEC14" href="#TOC1">LOCALE SUPPORT</a><br>
+<P>
+PCRE handles caseless matching, and determines whether characters are letters,
+digits, or whatever, by reference to a set of tables, indexed by character
+code point. When running in UTF-8 mode, or in the 16- or 32-bit libraries, this
+applies only to characters with code points less than 256. By default,
+higher-valued code points never match escapes such as \w or \d. However, if
+PCRE is built with Unicode property support, all characters can be tested with
+\p and \P, or, alternatively, the PCRE_UCP option can be set when a pattern
+is compiled; this causes \w and friends to use Unicode property support
+instead of the built-in tables.
+</P>
+<P>
+The use of locales with Unicode is discouraged. If you are handling characters
+with code points greater than 128, you should either use Unicode support, or
+use locales, but not try to mix the two.
+</P>
+<P>
+PCRE contains an internal set of tables that are used when the final argument
+of <b>pcre_compile()</b> is NULL. These are sufficient for many applications.
+Normally, the internal tables recognize only ASCII characters. However, when
+PCRE is built, it is possible to cause the internal tables to be rebuilt in the
+default "C" locale of the local system, which may cause them to be different.
+</P>
+<P>
+The internal tables can always be overridden by tables supplied by the
+application that calls PCRE. These may be created in a different locale from
+the default. As more and more applications change to using Unicode, the need
+for this locale support is expected to die away.
+</P>
+<P>
+External tables are built by calling the <b>pcre_maketables()</b> function,
+which has no arguments, in the relevant locale. The result can then be passed
+to <b>pcre_compile()</b> as often as necessary. For example, to build and use
+tables that are appropriate for the French locale (where accented characters
+with values greater than 128 are treated as letters), the following code could
+be used:
+<pre>
+  setlocale(LC_CTYPE, "fr_FR");
+  tables = pcre_maketables();
+  re = pcre_compile(..., tables);
+</pre>
+The locale name "fr_FR" is used on Linux and other Unix-like systems; if you
+are using Windows, the name for the French locale is "french".
+</P>
+<P>
+When <b>pcre_maketables()</b> runs, the tables are built in memory that is
+obtained via <b>pcre_malloc</b>. It is the caller's responsibility to ensure
+that the memory containing the tables remains available for as long as it is
+needed.
+</P>
+<P>
+The pointer that is passed to <b>pcre_compile()</b> is saved with the compiled
+pattern, and the same tables are used via this pointer by <b>pcre_study()</b>
+and also by <b>pcre_exec()</b> and <b>pcre_dfa_exec()</b>. Thus, for any single
+pattern, compilation, studying and matching all happen in the same locale, but
+different patterns can be processed in different locales.
+</P>
+<P>
+It is possible to pass a table pointer or NULL (indicating the use of the
+internal tables) to <b>pcre_exec()</b> or <b>pcre_dfa_exec()</b> (see the
+discussion below in the section on matching a pattern). This facility is
+provided for use with pre-compiled patterns that have been saved and reloaded.
+Character tables are not saved with patterns, so if a non-standard table was
+used at compile time, it must be provided again when the reloaded pattern is
+matched. Attempting to use this facility to match a pattern in a different
+locale from the one in which it was compiled is likely to lead to anomalous
+(usually incorrect) results.
+<a name="infoaboutpattern"></a></P>
+<br><a name="SEC15" href="#TOC1">INFORMATION ABOUT A PATTERN</a><br>
+<P>
+<b>int pcre_fullinfo(const pcre *<i>code</i>, const pcre_extra *<i>extra</i>,</b>
+<b>     int <i>what</i>, void *<i>where</i>);</b>
+</P>
+<P>
+The <b>pcre_fullinfo()</b> function returns information about a compiled
+pattern. It replaces the <b>pcre_info()</b> function, which was removed from the
+library at version 8.30, after more than 10 years of obsolescence.
+</P>
+<P>
+The first argument for <b>pcre_fullinfo()</b> is a pointer to the compiled
+pattern. The second argument is the result of <b>pcre_study()</b>, or NULL if
+the pattern was not studied. The third argument specifies which piece of
+information is required, and the fourth argument is a pointer to a variable
+to receive the data. The yield of the function is zero for success, or one of
+the following negative numbers:
+<pre>
+  PCRE_ERROR_NULL           the argument <i>code</i> was NULL
+                            the argument <i>where</i> was NULL
+  PCRE_ERROR_BADMAGIC       the "magic number" was not found
+  PCRE_ERROR_BADENDIANNESS  the pattern was compiled with different
+                            endianness
+  PCRE_ERROR_BADOPTION      the value of <i>what</i> was invalid
+  PCRE_ERROR_UNSET          the requested field is not set
+</pre>
+The "magic number" is placed at the start of each compiled pattern as an simple
+check against passing an arbitrary memory pointer. The endianness error can
+occur if a compiled pattern is saved and reloaded on a different host. Here is
+a typical call of <b>pcre_fullinfo()</b>, to obtain the length of the compiled
+pattern:
+<pre>
+  int rc;
+  size_t length;
+  rc = pcre_fullinfo(
+    re,               /* result of pcre_compile() */
+    sd,               /* result of pcre_study(), or NULL */
+    PCRE_INFO_SIZE,   /* what is required */
+    &length);         /* where to put the data */
+</pre>
+The possible values for the third argument are defined in <b>pcre.h</b>, and are
+as follows:
+<pre>
+  PCRE_INFO_BACKREFMAX
+</pre>
+Return the number of the highest back reference in the pattern. The fourth
+argument should point to an <b>int</b> variable. Zero is returned if there are
+no back references.
+<pre>
+  PCRE_INFO_CAPTURECOUNT
+</pre>
+Return the number of capturing subpatterns in the pattern. The fourth argument
+should point to an <b>int</b> variable.
+<pre>
+  PCRE_INFO_DEFAULT_TABLES
+</pre>
+Return a pointer to the internal default character tables within PCRE. The
+fourth argument should point to an <b>unsigned char *</b> variable. This
+information call is provided for internal use by the <b>pcre_study()</b>
+function. External callers can cause PCRE to use its internal tables by passing
+a NULL table pointer.
+<pre>
+  PCRE_INFO_FIRSTBYTE (deprecated)
+</pre>
+Return information about the first data unit of any matched string, for a
+non-anchored pattern. The name of this option refers to the 8-bit library,
+where data units are bytes. The fourth argument should point to an <b>int</b>
+variable. Negative values are used for special cases. However, this means that
+when the 32-bit library is in non-UTF-32 mode, the full 32-bit range of
+characters cannot be returned. For this reason, this value is deprecated; use
+PCRE_INFO_FIRSTCHARACTERFLAGS and PCRE_INFO_FIRSTCHARACTER instead.
+</P>
+<P>
+If there is a fixed first value, for example, the letter "c" from a pattern
+such as (cat|cow|coyote), its value is returned. In the 8-bit library, the
+value is always less than 256. In the 16-bit library the value can be up to
+0xffff. In the 32-bit library the value can be up to 0x10ffff.
+</P>
+<P>
+If there is no fixed first value, and if either
+<br>
+<br>
+(a) the pattern was compiled with the PCRE_MULTILINE option, and every branch
+starts with "^", or
+<br>
+<br>
+(b) every branch of the pattern starts with ".*" and PCRE_DOTALL is not set
+(if it were set, the pattern would be anchored),
+<br>
+<br>
+-1 is returned, indicating that the pattern matches only at the start of a
+subject string or after any newline within the string. Otherwise -2 is
+returned. For anchored patterns, -2 is returned.
+<pre>
+  PCRE_INFO_FIRSTCHARACTER
+</pre>
+Return the value of the first data unit (non-UTF character) of any matched
+string in the situation where PCRE_INFO_FIRSTCHARACTERFLAGS returns 1;
+otherwise return 0. The fourth argument should point to an <b>uint_t</b>
+variable.
+</P>
+<P>
+In the 8-bit library, the value is always less than 256. In the 16-bit library
+the value can be up to 0xffff. In the 32-bit library in UTF-32 mode the value
+can be up to 0x10ffff, and up to 0xffffffff when not using UTF-32 mode.
+<pre>
+  PCRE_INFO_FIRSTCHARACTERFLAGS
+</pre>
+Return information about the first data unit of any matched string, for a
+non-anchored pattern. The fourth argument should point to an <b>int</b>
+variable.
+</P>
+<P>
+If there is a fixed first value, for example, the letter "c" from a pattern
+such as (cat|cow|coyote), 1 is returned, and the character value can be
+retrieved using PCRE_INFO_FIRSTCHARACTER. If there is no fixed first value, and
+if either
+<br>
+<br>
+(a) the pattern was compiled with the PCRE_MULTILINE option, and every branch
+starts with "^", or
+<br>
+<br>
+(b) every branch of the pattern starts with ".*" and PCRE_DOTALL is not set
+(if it were set, the pattern would be anchored),
+<br>
+<br>
+2 is returned, indicating that the pattern matches only at the start of a
+subject string or after any newline within the string. Otherwise 0 is
+returned. For anchored patterns, 0 is returned.
+<pre>
+  PCRE_INFO_FIRSTTABLE
+</pre>
+If the pattern was studied, and this resulted in the construction of a 256-bit
+table indicating a fixed set of values for the first data unit in any matching
+string, a pointer to the table is returned. Otherwise NULL is returned. The
+fourth argument should point to an <b>unsigned char *</b> variable.
+<pre>
+  PCRE_INFO_HASCRORLF
+</pre>
+Return 1 if the pattern contains any explicit matches for CR or LF characters,
+otherwise 0. The fourth argument should point to an <b>int</b> variable. An
+explicit match is either a literal CR or LF character, or \r or \n.
+<pre>
+  PCRE_INFO_JCHANGED
+</pre>
+Return 1 if the (?J) or (?-J) option setting is used in the pattern, otherwise
+0. The fourth argument should point to an <b>int</b> variable. (?J) and
+(?-J) set and unset the local PCRE_DUPNAMES option, respectively.
+<pre>
+  PCRE_INFO_JIT
+</pre>
+Return 1 if the pattern was studied with one of the JIT options, and
+just-in-time compiling was successful. The fourth argument should point to an
+<b>int</b> variable. A return value of 0 means that JIT support is not available
+in this version of PCRE, or that the pattern was not studied with a JIT option,
+or that the JIT compiler could not handle this particular pattern. See the
+<a href="pcrejit.html"><b>pcrejit</b></a>
+documentation for details of what can and cannot be handled.
+<pre>
+  PCRE_INFO_JITSIZE
+</pre>
+If the pattern was successfully studied with a JIT option, return the size of
+the JIT compiled code, otherwise return zero. The fourth argument should point
+to a <b>size_t</b> variable.
+<pre>
+  PCRE_INFO_LASTLITERAL
+</pre>
+Return the value of the rightmost literal data unit that must exist in any
+matched string, other than at its start, if such a value has been recorded. The
+fourth argument should point to an <b>int</b> variable. If there is no such
+value, -1 is returned. For anchored patterns, a last literal value is recorded
+only if it follows something of variable length. For example, for the pattern
+/^a\d+z\d+/ the returned value is "z", but for /^a\dz\d/ the returned value
+is -1.
+</P>
+<P>
+Since for the 32-bit library using the non-UTF-32 mode, this function is unable
+to return the full 32-bit range of characters, this value is deprecated;
+instead the PCRE_INFO_REQUIREDCHARFLAGS and PCRE_INFO_REQUIREDCHAR values should
+be used.
+<pre>
+  PCRE_INFO_MATCH_EMPTY
+</pre>
+Return 1 if the pattern can match an empty string, otherwise 0. The fourth
+argument should point to an <b>int</b> variable.
+<pre>
+  PCRE_INFO_MATCHLIMIT
+</pre>
+If the pattern set a match limit by including an item of the form
+(*LIMIT_MATCH=nnnn) at the start, the value is returned. The fourth argument
+should point to an unsigned 32-bit integer. If no such value has been set, the
+call to <b>pcre_fullinfo()</b> returns the error PCRE_ERROR_UNSET.
+<pre>
+  PCRE_INFO_MAXLOOKBEHIND
+</pre>
+Return the number of characters (NB not data units) in the longest lookbehind
+assertion in the pattern. This information is useful when doing multi-segment
+matching using the partial matching facilities. Note that the simple assertions
+\b and \B require a one-character lookbehind. \A also registers a
+one-character lookbehind, though it does not actually inspect the previous
+character. This is to ensure that at least one character from the old segment
+is retained when a new segment is processed. Otherwise, if there are no
+lookbehinds in the pattern, \A might match incorrectly at the start of a new
+segment.
+<pre>
+  PCRE_INFO_MINLENGTH
+</pre>
+If the pattern was studied and a minimum length for matching subject strings
+was computed, its value is returned. Otherwise the returned value is -1. The
+value is a number of characters, which in UTF mode may be different from the
+number of data units. The fourth argument should point to an <b>int</b>
+variable. A non-negative value is a lower bound to the length of any matching
+string. There may not be any strings of that length that do actually match, but
+every string that does match is at least that long.
+<pre>
+  PCRE_INFO_NAMECOUNT
+  PCRE_INFO_NAMEENTRYSIZE
+  PCRE_INFO_NAMETABLE
+</pre>
+PCRE supports the use of named as well as numbered capturing parentheses. The
+names are just an additional way of identifying the parentheses, which still
+acquire numbers. Several convenience functions such as
+<b>pcre_get_named_substring()</b> are provided for extracting captured
+substrings by name. It is also possible to extract the data directly, by first
+converting the name to a number in order to access the correct pointers in the
+output vector (described with <b>pcre_exec()</b> below). To do the conversion,
+you need to use the name-to-number map, which is described by these three
+values.
+</P>
+<P>
+The map consists of a number of fixed-size entries. PCRE_INFO_NAMECOUNT gives
+the number of entries, and PCRE_INFO_NAMEENTRYSIZE gives the size of each
+entry; both of these return an <b>int</b> value. The entry size depends on the
+length of the longest name. PCRE_INFO_NAMETABLE returns a pointer to the first
+entry of the table. This is a pointer to <b>char</b> in the 8-bit library, where
+the first two bytes of each entry are the number of the capturing parenthesis,
+most significant byte first. In the 16-bit library, the pointer points to
+16-bit data units, the first of which contains the parenthesis number. In the
+32-bit library, the pointer points to 32-bit data units, the first of which
+contains the parenthesis number. The rest of the entry is the corresponding
+name, zero terminated.
+</P>
+<P>
+The names are in alphabetical order. If (?| is used to create multiple groups
+with the same number, as described in the
+<a href="pcrepattern.html#dupsubpatternnumber">section on duplicate subpattern numbers</a>
+in the
+<a href="pcrepattern.html"><b>pcrepattern</b></a>
+page, the groups may be given the same name, but there is only one entry in the
+table. Different names for groups of the same number are not permitted.
+Duplicate names for subpatterns with different numbers are permitted,
+but only if PCRE_DUPNAMES is set. They appear in the table in the order in
+which they were found in the pattern. In the absence of (?| this is the order
+of increasing number; when (?| is used this is not necessarily the case because
+later subpatterns may have lower numbers.
+</P>
+<P>
+As a simple example of the name/number table, consider the following pattern
+after compilation by the 8-bit library (assume PCRE_EXTENDED is set, so white
+space - including newlines - is ignored):
+<pre>
+  (?&#60;date&#62; (?&#60;year&#62;(\d\d)?\d\d) - (?&#60;month&#62;\d\d) - (?&#60;day&#62;\d\d) )
+</pre>
+There are four named subpatterns, so the table has four entries, and each entry
+in the table is eight bytes long. The table is as follows, with non-printing
+bytes shows in hexadecimal, and undefined bytes shown as ??:
+<pre>
+  00 01 d  a  t  e  00 ??
+  00 05 d  a  y  00 ?? ??
+  00 04 m  o  n  t  h  00
+  00 02 y  e  a  r  00 ??
+</pre>
+When writing code to extract data from named subpatterns using the
+name-to-number map, remember that the length of the entries is likely to be
+different for each compiled pattern.
+<pre>
+  PCRE_INFO_OKPARTIAL
+</pre>
+Return 1 if the pattern can be used for partial matching with
+<b>pcre_exec()</b>, otherwise 0. The fourth argument should point to an
+<b>int</b> variable. From release 8.00, this always returns 1, because the
+restrictions that previously applied to partial matching have been lifted. The
+<a href="pcrepartial.html"><b>pcrepartial</b></a>
+documentation gives details of partial matching.
+<pre>
+  PCRE_INFO_OPTIONS
+</pre>
+Return a copy of the options with which the pattern was compiled. The fourth
+argument should point to an <b>unsigned long int</b> variable. These option bits
+are those specified in the call to <b>pcre_compile()</b>, modified by any
+top-level option settings at the start of the pattern itself. In other words,
+they are the options that will be in force when matching starts. For example,
+if the pattern /(?im)abc(?-i)d/ is compiled with the PCRE_EXTENDED option, the
+result is PCRE_CASELESS, PCRE_MULTILINE, and PCRE_EXTENDED.
+</P>
+<P>
+A pattern is automatically anchored by PCRE if all of its top-level
+alternatives begin with one of the following:
+<pre>
+  ^     unless PCRE_MULTILINE is set
+  \A    always
+  \G    always
+  .*    if PCRE_DOTALL is set and there are no back references to the subpattern in which .* appears
+</pre>
+For such patterns, the PCRE_ANCHORED bit is set in the options returned by
+<b>pcre_fullinfo()</b>.
+<pre>
+  PCRE_INFO_RECURSIONLIMIT
+</pre>
+If the pattern set a recursion limit by including an item of the form
+(*LIMIT_RECURSION=nnnn) at the start, the value is returned. The fourth
+argument should point to an unsigned 32-bit integer. If no such value has been
+set, the call to <b>pcre_fullinfo()</b> returns the error PCRE_ERROR_UNSET.
+<pre>
+  PCRE_INFO_SIZE
+</pre>
+Return the size of the compiled pattern in bytes (for all three libraries). The
+fourth argument should point to a <b>size_t</b> variable. This value does not
+include the size of the <b>pcre</b> structure that is returned by
+<b>pcre_compile()</b>. The value that is passed as the argument to
+<b>pcre_malloc()</b> when <b>pcre_compile()</b> is getting memory in which to
+place the compiled data is the value returned by this option plus the size of
+the <b>pcre</b> structure. Studying a compiled pattern, with or without JIT,
+does not alter the value returned by this option.
+<pre>
+  PCRE_INFO_STUDYSIZE
+</pre>
+Return the size in bytes (for all three libraries) of the data block pointed to
+by the <i>study_data</i> field in a <b>pcre_extra</b> block. If <b>pcre_extra</b>
+is NULL, or there is no study data, zero is returned. The fourth argument
+should point to a <b>size_t</b> variable. The <i>study_data</i> field is set by
+<b>pcre_study()</b> to record information that will speed up matching (see the
+section entitled
+<a href="#studyingapattern">"Studying a pattern"</a>
+above). The format of the <i>study_data</i> block is private, but its length
+is made available via this option so that it can be saved and restored (see the
+<a href="pcreprecompile.html"><b>pcreprecompile</b></a>
+documentation for details).
+<pre>
+  PCRE_INFO_REQUIREDCHARFLAGS
+</pre>
+Returns 1 if there is a rightmost literal data unit that must exist in any
+matched string, other than at its start. The fourth argument should  point to
+an <b>int</b> variable. If there is no such value, 0 is returned. If returning
+1, the character value itself can be retrieved using PCRE_INFO_REQUIREDCHAR.
+</P>
+<P>
+For anchored patterns, a last literal value is recorded only if it follows
+something of variable length. For example, for the pattern /^a\d+z\d+/ the
+returned value 1 (with "z" returned from PCRE_INFO_REQUIREDCHAR), but for
+/^a\dz\d/ the returned value is 0.
+<pre>
+  PCRE_INFO_REQUIREDCHAR
+</pre>
+Return the value of the rightmost literal data unit that must exist in any
+matched string, other than at its start, if such a value has been recorded. The
+fourth argument should point to an <b>uint32_t</b> variable. If there is no such
+value, 0 is returned.
+</P>
+<br><a name="SEC16" href="#TOC1">REFERENCE COUNTS</a><br>
+<P>
+<b>int pcre_refcount(pcre *<i>code</i>, int <i>adjust</i>);</b>
+</P>
+<P>
+The <b>pcre_refcount()</b> function is used to maintain a reference count in the
+data block that contains a compiled pattern. It is provided for the benefit of
+applications that operate in an object-oriented manner, where different parts
+of the application may be using the same compiled pattern, but you want to free
+the block when they are all done.
+</P>
+<P>
+When a pattern is compiled, the reference count field is initialized to zero.
+It is changed only by calling this function, whose action is to add the
+<i>adjust</i> value (which may be positive or negative) to it. The yield of the
+function is the new value. However, the value of the count is constrained to
+lie between 0 and 65535, inclusive. If the new value is outside these limits,
+it is forced to the appropriate limit value.
+</P>
+<P>
+Except when it is zero, the reference count is not correctly preserved if a
+pattern is compiled on one host and then transferred to a host whose byte-order
+is different. (This seems a highly unlikely scenario.)
+</P>
+<br><a name="SEC17" href="#TOC1">MATCHING A PATTERN: THE TRADITIONAL FUNCTION</a><br>
+<P>
+<b>int pcre_exec(const pcre *<i>code</i>, const pcre_extra *<i>extra</i>,</b>
+<b>     const char *<i>subject</i>, int <i>length</i>, int <i>startoffset</i>,</b>
+<b>     int <i>options</i>, int *<i>ovector</i>, int <i>ovecsize</i>);</b>
+</P>
+<P>
+The function <b>pcre_exec()</b> is called to match a subject string against a
+compiled pattern, which is passed in the <i>code</i> argument. If the
+pattern was studied, the result of the study should be passed in the
+<i>extra</i> argument. You can call <b>pcre_exec()</b> with the same <i>code</i>
+and <i>extra</i> arguments as many times as you like, in order to match
+different subject strings with the same pattern.
+</P>
+<P>
+This function is the main matching facility of the library, and it operates in
+a Perl-like manner. For specialist use there is also an alternative matching
+function, which is described
+<a href="#dfamatch">below</a>
+in the section about the <b>pcre_dfa_exec()</b> function.
+</P>
+<P>
+In most applications, the pattern will have been compiled (and optionally
+studied) in the same process that calls <b>pcre_exec()</b>. However, it is
+possible to save compiled patterns and study data, and then use them later
+in different processes, possibly even on different hosts. For a discussion
+about this, see the
+<a href="pcreprecompile.html"><b>pcreprecompile</b></a>
+documentation.
+</P>
+<P>
+Here is an example of a simple call to <b>pcre_exec()</b>:
+<pre>
+  int rc;
+  int ovector[30];
+  rc = pcre_exec(
+    re,             /* result of pcre_compile() */
+    NULL,           /* we didn't study the pattern */
+    "some string",  /* the subject string */
+    11,             /* the length of the subject string */
+    0,              /* start at offset 0 in the subject */
+    0,              /* default options */
+    ovector,        /* vector of integers for substring information */
+    30);            /* number of elements (NOT size in bytes) */
+<a name="extradata"></a></PRE>
+</P>
+<br><b>
+Extra data for <b>pcre_exec()</b>
+</b><br>
+<P>
+If the <i>extra</i> argument is not NULL, it must point to a <b>pcre_extra</b>
+data block. The <b>pcre_study()</b> function returns such a block (when it
+doesn't return NULL), but you can also create one for yourself, and pass
+additional information in it. The <b>pcre_extra</b> block contains the following
+fields (not necessarily in this order):
+<pre>
+  unsigned long int <i>flags</i>;
+  void *<i>study_data</i>;
+  void *<i>executable_jit</i>;
+  unsigned long int <i>match_limit</i>;
+  unsigned long int <i>match_limit_recursion</i>;
+  void *<i>callout_data</i>;
+  const unsigned char *<i>tables</i>;
+  unsigned char **<i>mark</i>;
+</pre>
+In the 16-bit version of this structure, the <i>mark</i> field has type
+"PCRE_UCHAR16 **".
+<br>
+<br>
+In the 32-bit version of this structure, the <i>mark</i> field has type
+"PCRE_UCHAR32 **".
+</P>
+<P>
+The <i>flags</i> field is used to specify which of the other fields are set. The
+flag bits are:
+<pre>
+  PCRE_EXTRA_CALLOUT_DATA
+  PCRE_EXTRA_EXECUTABLE_JIT
+  PCRE_EXTRA_MARK
+  PCRE_EXTRA_MATCH_LIMIT
+  PCRE_EXTRA_MATCH_LIMIT_RECURSION
+  PCRE_EXTRA_STUDY_DATA
+  PCRE_EXTRA_TABLES
+</pre>
+Other flag bits should be set to zero. The <i>study_data</i> field and sometimes
+the <i>executable_jit</i> field are set in the <b>pcre_extra</b> block that is
+returned by <b>pcre_study()</b>, together with the appropriate flag bits. You
+should not set these yourself, but you may add to the block by setting other
+fields and their corresponding flag bits.
+</P>
+<P>
+The <i>match_limit</i> field provides a means of preventing PCRE from using up a
+vast amount of resources when running patterns that are not going to match,
+but which have a very large number of possibilities in their search trees. The
+classic example is a pattern that uses nested unlimited repeats.
+</P>
+<P>
+Internally, <b>pcre_exec()</b> uses a function called <b>match()</b>, which it
+calls repeatedly (sometimes recursively). The limit set by <i>match_limit</i> is
+imposed on the number of times this function is called during a match, which
+has the effect of limiting the amount of backtracking that can take place. For
+patterns that are not anchored, the count restarts from zero for each position
+in the subject string.
+</P>
+<P>
+When <b>pcre_exec()</b> is called with a pattern that was successfully studied
+with a JIT option, the way that the matching is executed is entirely different.
+However, there is still the possibility of runaway matching that goes on for a
+very long time, and so the <i>match_limit</i> value is also used in this case
+(but in a different way) to limit how long the matching can continue.
+</P>
+<P>
+The default value for the limit can be set when PCRE is built; the default
+default is 10 million, which handles all but the most extreme cases. You can
+override the default by suppling <b>pcre_exec()</b> with a <b>pcre_extra</b>
+block in which <i>match_limit</i> is set, and PCRE_EXTRA_MATCH_LIMIT is set in
+the <i>flags</i> field. If the limit is exceeded, <b>pcre_exec()</b> returns
+PCRE_ERROR_MATCHLIMIT.
+</P>
+<P>
+A value for the match limit may also be supplied by an item at the start of a
+pattern of the form
+<pre>
+  (*LIMIT_MATCH=d)
+</pre>
+where d is a decimal number. However, such a setting is ignored unless d is
+less than the limit set by the caller of <b>pcre_exec()</b> or, if no such limit
+is set, less than the default.
+</P>
+<P>
+The <i>match_limit_recursion</i> field is similar to <i>match_limit</i>, but
+instead of limiting the total number of times that <b>match()</b> is called, it
+limits the depth of recursion. The recursion depth is a smaller number than the
+total number of calls, because not all calls to <b>match()</b> are recursive.
+This limit is of use only if it is set smaller than <i>match_limit</i>.
+</P>
+<P>
+Limiting the recursion depth limits the amount of machine stack that can be
+used, or, when PCRE has been compiled to use memory on the heap instead of the
+stack, the amount of heap memory that can be used. This limit is not relevant,
+and is ignored, when matching is done using JIT compiled code.
+</P>
+<P>
+The default value for <i>match_limit_recursion</i> can be set when PCRE is
+built; the default default is the same value as the default for
+<i>match_limit</i>. You can override the default by suppling <b>pcre_exec()</b>
+with a <b>pcre_extra</b> block in which <i>match_limit_recursion</i> is set, and
+PCRE_EXTRA_MATCH_LIMIT_RECURSION is set in the <i>flags</i> field. If the limit
+is exceeded, <b>pcre_exec()</b> returns PCRE_ERROR_RECURSIONLIMIT.
+</P>
+<P>
+A value for the recursion limit may also be supplied by an item at the start of
+a pattern of the form
+<pre>
+  (*LIMIT_RECURSION=d)
+</pre>
+where d is a decimal number. However, such a setting is ignored unless d is
+less than the limit set by the caller of <b>pcre_exec()</b> or, if no such limit
+is set, less than the default.
+</P>
+<P>
+The <i>callout_data</i> field is used in conjunction with the "callout" feature,
+and is described in the
+<a href="pcrecallout.html"><b>pcrecallout</b></a>
+documentation.
+</P>
+<P>
+The <i>tables</i> field is provided for use with patterns that have been
+pre-compiled using custom character tables, saved to disc or elsewhere, and
+then reloaded, because the tables that were used to compile a pattern are not
+saved with it. See the
+<a href="pcreprecompile.html"><b>pcreprecompile</b></a>
+documentation for a discussion of saving compiled patterns for later use. If
+NULL is passed using this mechanism, it forces PCRE's internal tables to be
+used.
+</P>
+<P>
+<b>Warning:</b> The tables that <b>pcre_exec()</b> uses must be the same as those
+that were used when the pattern was compiled. If this is not the case, the
+behaviour of <b>pcre_exec()</b> is undefined. Therefore, when a pattern is
+compiled and matched in the same process, this field should never be set. In
+this (the most common) case, the correct table pointer is automatically passed
+with the compiled pattern from <b>pcre_compile()</b> to <b>pcre_exec()</b>.
+</P>
+<P>
+If PCRE_EXTRA_MARK is set in the <i>flags</i> field, the <i>mark</i> field must
+be set to point to a suitable variable. If the pattern contains any
+backtracking control verbs such as (*MARK:NAME), and the execution ends up with
+a name to pass back, a pointer to the name string (zero terminated) is placed
+in the variable pointed to by the <i>mark</i> field. The names are within the
+compiled pattern; if you wish to retain such a name you must copy it before
+freeing the memory of a compiled pattern. If there is no name to pass back, the
+variable pointed to by the <i>mark</i> field is set to NULL. For details of the
+backtracking control verbs, see the section entitled
+<a href="pcrepattern#backtrackcontrol">"Backtracking control"</a>
+in the
+<a href="pcrepattern.html"><b>pcrepattern</b></a>
+documentation.
+<a name="execoptions"></a></P>
+<br><b>
+Option bits for <b>pcre_exec()</b>
+</b><br>
+<P>
+The unused bits of the <i>options</i> argument for <b>pcre_exec()</b> must be
+zero. The only bits that may be set are PCRE_ANCHORED, PCRE_NEWLINE_<i>xxx</i>,
+PCRE_NOTBOL, PCRE_NOTEOL, PCRE_NOTEMPTY, PCRE_NOTEMPTY_ATSTART,
+PCRE_NO_START_OPTIMIZE, PCRE_NO_UTF8_CHECK, PCRE_PARTIAL_HARD, and
+PCRE_PARTIAL_SOFT.
+</P>
+<P>
+If the pattern was successfully studied with one of the just-in-time (JIT)
+compile options, the only supported options for JIT execution are
+PCRE_NO_UTF8_CHECK, PCRE_NOTBOL, PCRE_NOTEOL, PCRE_NOTEMPTY,
+PCRE_NOTEMPTY_ATSTART, PCRE_PARTIAL_HARD, and PCRE_PARTIAL_SOFT. If an
+unsupported option is used, JIT execution is disabled and the normal
+interpretive code in <b>pcre_exec()</b> is run.
+<pre>
+  PCRE_ANCHORED
+</pre>
+The PCRE_ANCHORED option limits <b>pcre_exec()</b> to matching at the first
+matching position. If a pattern was compiled with PCRE_ANCHORED, or turned out
+to be anchored by virtue of its contents, it cannot be made unachored at
+matching time.
+<pre>
+  PCRE_BSR_ANYCRLF
+  PCRE_BSR_UNICODE
+</pre>
+These options (which are mutually exclusive) control what the \R escape
+sequence matches. The choice is either to match only CR, LF, or CRLF, or to
+match any Unicode newline sequence. These options override the choice that was
+made or defaulted when the pattern was compiled.
+<pre>
+  PCRE_NEWLINE_CR
+  PCRE_NEWLINE_LF
+  PCRE_NEWLINE_CRLF
+  PCRE_NEWLINE_ANYCRLF
+  PCRE_NEWLINE_ANY
+</pre>
+These options override the newline definition that was chosen or defaulted when
+the pattern was compiled. For details, see the description of
+<b>pcre_compile()</b> above. During matching, the newline choice affects the
+behaviour of the dot, circumflex, and dollar metacharacters. It may also alter
+the way the match position is advanced after a match failure for an unanchored
+pattern.
+</P>
+<P>
+When PCRE_NEWLINE_CRLF, PCRE_NEWLINE_ANYCRLF, or PCRE_NEWLINE_ANY is set, and a
+match attempt for an unanchored pattern fails when the current position is at a
+CRLF sequence, and the pattern contains no explicit matches for CR or LF
+characters, the match position is advanced by two characters instead of one, in
+other words, to after the CRLF.
+</P>
+<P>
+The above rule is a compromise that makes the most common cases work as
+expected. For example, if the pattern is .+A (and the PCRE_DOTALL option is not
+set), it does not match the string "\r\nA" because, after failing at the
+start, it skips both the CR and the LF before retrying. However, the pattern
+[\r\n]A does match that string, because it contains an explicit CR or LF
+reference, and so advances only by one character after the first failure.
+</P>
+<P>
+An explicit match for CR of LF is either a literal appearance of one of those
+characters, or one of the \r or \n escape sequences. Implicit matches such as
+[^X] do not count, nor does \s (which includes CR and LF in the characters
+that it matches).
+</P>
+<P>
+Notwithstanding the above, anomalous effects may still occur when CRLF is a
+valid newline sequence and explicit \r or \n escapes appear in the pattern.
+<pre>
+  PCRE_NOTBOL
+</pre>
+This option specifies that first character of the subject string is not the
+beginning of a line, so the circumflex metacharacter should not match before
+it. Setting this without PCRE_MULTILINE (at compile time) causes circumflex
+never to match. This option affects only the behaviour of the circumflex
+metacharacter. It does not affect \A.
+<pre>
+  PCRE_NOTEOL
+</pre>
+This option specifies that the end of the subject string is not the end of a
+line, so the dollar metacharacter should not match it nor (except in multiline
+mode) a newline immediately before it. Setting this without PCRE_MULTILINE (at
+compile time) causes dollar never to match. This option affects only the
+behaviour of the dollar metacharacter. It does not affect \Z or \z.
+<pre>
+  PCRE_NOTEMPTY
+</pre>
+An empty string is not considered to be a valid match if this option is set. If
+there are alternatives in the pattern, they are tried. If all the alternatives
+match the empty string, the entire match fails. For example, if the pattern
+<pre>
+  a?b?
+</pre>
+is applied to a string not beginning with "a" or "b", it matches an empty
+string at the start of the subject. With PCRE_NOTEMPTY set, this match is not
+valid, so PCRE searches further into the string for occurrences of "a" or "b".
+<pre>
+  PCRE_NOTEMPTY_ATSTART
+</pre>
+This is like PCRE_NOTEMPTY, except that an empty string match that is not at
+the start of the subject is permitted. If the pattern is anchored, such a match
+can occur only if the pattern contains \K.
+</P>
+<P>
+Perl has no direct equivalent of PCRE_NOTEMPTY or PCRE_NOTEMPTY_ATSTART, but it
+does make a special case of a pattern match of the empty string within its
+<b>split()</b> function, and when using the /g modifier. It is possible to
+emulate Perl's behaviour after matching a null string by first trying the match
+again at the same offset with PCRE_NOTEMPTY_ATSTART and PCRE_ANCHORED, and then
+if that fails, by advancing the starting offset (see below) and trying an
+ordinary match again. There is some code that demonstrates how to do this in
+the
+<a href="pcredemo.html"><b>pcredemo</b></a>
+sample program. In the most general case, you have to check to see if the
+newline convention recognizes CRLF as a newline, and if so, and the current
+character is CR followed by LF, advance the starting offset by two characters
+instead of one.
+<pre>
+  PCRE_NO_START_OPTIMIZE
+</pre>
+There are a number of optimizations that <b>pcre_exec()</b> uses at the start of
+a match, in order to speed up the process. For example, if it is known that an
+unanchored match must start with a specific character, it searches the subject
+for that character, and fails immediately if it cannot find it, without
+actually running the main matching function. This means that a special item
+such as (*COMMIT) at the start of a pattern is not considered until after a
+suitable starting point for the match has been found. Also, when callouts or
+(*MARK) items are in use, these "start-up" optimizations can cause them to be
+skipped if the pattern is never actually used. The start-up optimizations are
+in effect a pre-scan of the subject that takes place before the pattern is run.
+</P>
+<P>
+The PCRE_NO_START_OPTIMIZE option disables the start-up optimizations, possibly
+causing performance to suffer, but ensuring that in cases where the result is
+"no match", the callouts do occur, and that items such as (*COMMIT) and (*MARK)
+are considered at every possible starting position in the subject string. If
+PCRE_NO_START_OPTIMIZE is set at compile time, it cannot be unset at matching
+time. The use of PCRE_NO_START_OPTIMIZE at matching time (that is, passing it
+to <b>pcre_exec()</b>) disables JIT execution; in this situation, matching is
+always done using interpretively.
+</P>
+<P>
+Setting PCRE_NO_START_OPTIMIZE can change the outcome of a matching operation.
+Consider the pattern
+<pre>
+  (*COMMIT)ABC
+</pre>
+When this is compiled, PCRE records the fact that a match must start with the
+character "A". Suppose the subject string is "DEFABC". The start-up
+optimization scans along the subject, finds "A" and runs the first match
+attempt from there. The (*COMMIT) item means that the pattern must match the
+current starting position, which in this case, it does. However, if the same
+match is run with PCRE_NO_START_OPTIMIZE set, the initial scan along the
+subject string does not happen. The first match attempt is run starting from
+"D" and when this fails, (*COMMIT) prevents any further matches being tried, so
+the overall result is "no match". If the pattern is studied, more start-up
+optimizations may be used. For example, a minimum length for the subject may be
+recorded. Consider the pattern
+<pre>
+  (*MARK:A)(X|Y)
+</pre>
+The minimum length for a match is one character. If the subject is "ABC", there
+will be attempts to match "ABC", "BC", "C", and then finally an empty string.
+If the pattern is studied, the final attempt does not take place, because PCRE
+knows that the subject is too short, and so the (*MARK) is never encountered.
+In this case, studying the pattern does not affect the overall match result,
+which is still "no match", but it does affect the auxiliary information that is
+returned.
+<pre>
+  PCRE_NO_UTF8_CHECK
+</pre>
+When PCRE_UTF8 is set at compile time, the validity of the subject as a UTF-8
+string is automatically checked when <b>pcre_exec()</b> is subsequently called.
+The entire string is checked before any other processing takes place. The value
+of <i>startoffset</i> is also checked to ensure that it points to the start of a
+UTF-8 character. There is a discussion about the
+<a href="pcreunicode.html#utf8strings">validity of UTF-8 strings</a>
+in the
+<a href="pcreunicode.html"><b>pcreunicode</b></a>
+page. If an invalid sequence of bytes is found, <b>pcre_exec()</b> returns the
+error PCRE_ERROR_BADUTF8 or, if PCRE_PARTIAL_HARD is set and the problem is a
+truncated character at the end of the subject, PCRE_ERROR_SHORTUTF8. In both
+cases, information about the precise nature of the error may also be returned
+(see the descriptions of these errors in the section entitled \fIError return
+values from\fP <b>pcre_exec()</b>
+<a href="#errorlist">below).</a>
+If <i>startoffset</i> contains a value that does not point to the start of a
+UTF-8 character (or to the end of the subject), PCRE_ERROR_BADUTF8_OFFSET is
+returned.
+</P>
+<P>
+If you already know that your subject is valid, and you want to skip these
+checks for performance reasons, you can set the PCRE_NO_UTF8_CHECK option when
+calling <b>pcre_exec()</b>. You might want to do this for the second and
+subsequent calls to <b>pcre_exec()</b> if you are making repeated calls to find
+all the matches in a single subject string. However, you should be sure that
+the value of <i>startoffset</i> points to the start of a character (or the end
+of the subject). When PCRE_NO_UTF8_CHECK is set, the effect of passing an
+invalid string as a subject or an invalid value of <i>startoffset</i> is
+undefined. Your program may crash or loop.
+<pre>
+  PCRE_PARTIAL_HARD
+  PCRE_PARTIAL_SOFT
+</pre>
+These options turn on the partial matching feature. For backwards
+compatibility, PCRE_PARTIAL is a synonym for PCRE_PARTIAL_SOFT. A partial match
+occurs if the end of the subject string is reached successfully, but there are
+not enough subject characters to complete the match. If this happens when
+PCRE_PARTIAL_SOFT (but not PCRE_PARTIAL_HARD) is set, matching continues by
+testing any remaining alternatives. Only if no complete match can be found is
+PCRE_ERROR_PARTIAL returned instead of PCRE_ERROR_NOMATCH. In other words,
+PCRE_PARTIAL_SOFT says that the caller is prepared to handle a partial match,
+but only if no complete match can be found.
+</P>
+<P>
+If PCRE_PARTIAL_HARD is set, it overrides PCRE_PARTIAL_SOFT. In this case, if a
+partial match is found, <b>pcre_exec()</b> immediately returns
+PCRE_ERROR_PARTIAL, without considering any other alternatives. In other words,
+when PCRE_PARTIAL_HARD is set, a partial match is considered to be more
+important that an alternative complete match.
+</P>
+<P>
+In both cases, the portion of the string that was inspected when the partial
+match was found is set as the first matching string. There is a more detailed
+discussion of partial and multi-segment matching, with examples, in the
+<a href="pcrepartial.html"><b>pcrepartial</b></a>
+documentation.
+</P>
+<br><b>
+The string to be matched by <b>pcre_exec()</b>
+</b><br>
+<P>
+The subject string is passed to <b>pcre_exec()</b> as a pointer in
+<i>subject</i>, a length in <i>length</i>, and a starting offset in
+<i>startoffset</i>. The units for <i>length</i> and <i>startoffset</i> are bytes
+for the 8-bit library, 16-bit data items for the 16-bit library, and 32-bit
+data items for the 32-bit library.
+</P>
+<P>
+If <i>startoffset</i> is negative or greater than the length of the subject,
+<b>pcre_exec()</b> returns PCRE_ERROR_BADOFFSET. When the starting offset is
+zero, the search for a match starts at the beginning of the subject, and this
+is by far the most common case. In UTF-8 or UTF-16 mode, the offset must point
+to the start of a character, or the end of the subject (in UTF-32 mode, one
+data unit equals one character, so all offsets are valid). Unlike the pattern
+string, the subject may contain binary zeroes.
+</P>
+<P>
+A non-zero starting offset is useful when searching for another match in the
+same subject by calling <b>pcre_exec()</b> again after a previous success.
+Setting <i>startoffset</i> differs from just passing over a shortened string and
+setting PCRE_NOTBOL in the case of a pattern that begins with any kind of
+lookbehind. For example, consider the pattern
+<pre>
+  \Biss\B
+</pre>
+which finds occurrences of "iss" in the middle of words. (\B matches only if
+the current position in the subject is not a word boundary.) When applied to
+the string "Mississipi" the first call to <b>pcre_exec()</b> finds the first
+occurrence. If <b>pcre_exec()</b> is called again with just the remainder of the
+subject, namely "issipi", it does not match, because \B is always false at the
+start of the subject, which is deemed to be a word boundary. However, if
+<b>pcre_exec()</b> is passed the entire string again, but with <i>startoffset</i>
+set to 4, it finds the second occurrence of "iss" because it is able to look
+behind the starting point to discover that it is preceded by a letter.
+</P>
+<P>
+Finding all the matches in a subject is tricky when the pattern can match an
+empty string. It is possible to emulate Perl's /g behaviour by first trying the
+match again at the same offset, with the PCRE_NOTEMPTY_ATSTART and
+PCRE_ANCHORED options, and then if that fails, advancing the starting offset
+and trying an ordinary match again. There is some code that demonstrates how to
+do this in the
+<a href="pcredemo.html"><b>pcredemo</b></a>
+sample program. In the most general case, you have to check to see if the
+newline convention recognizes CRLF as a newline, and if so, and the current
+character is CR followed by LF, advance the starting offset by two characters
+instead of one.
+</P>
+<P>
+If a non-zero starting offset is passed when the pattern is anchored, one
+attempt to match at the given offset is made. This can only succeed if the
+pattern does not require the match to be at the start of the subject.
+</P>
+<br><b>
+How <b>pcre_exec()</b> returns captured substrings
+</b><br>
+<P>
+In general, a pattern matches a certain portion of the subject, and in
+addition, further substrings from the subject may be picked out by parts of the
+pattern. Following the usage in Jeffrey Friedl's book, this is called
+"capturing" in what follows, and the phrase "capturing subpattern" is used for
+a fragment of a pattern that picks out a substring. PCRE supports several other
+kinds of parenthesized subpattern that do not cause substrings to be captured.
+</P>
+<P>
+Captured substrings are returned to the caller via a vector of integers whose
+address is passed in <i>ovector</i>. The number of elements in the vector is
+passed in <i>ovecsize</i>, which must be a non-negative number. <b>Note</b>: this
+argument is NOT the size of <i>ovector</i> in bytes.
+</P>
+<P>
+The first two-thirds of the vector is used to pass back captured substrings,
+each substring using a pair of integers. The remaining third of the vector is
+used as workspace by <b>pcre_exec()</b> while matching capturing subpatterns,
+and is not available for passing back information. The number passed in
+<i>ovecsize</i> should always be a multiple of three. If it is not, it is
+rounded down.
+</P>
+<P>
+When a match is successful, information about captured substrings is returned
+in pairs of integers, starting at the beginning of <i>ovector</i>, and
+continuing up to two-thirds of its length at the most. The first element of
+each pair is set to the offset of the first character in a substring, and the
+second is set to the offset of the first character after the end of a
+substring. These values are always data unit offsets, even in UTF mode. They
+are byte offsets in the 8-bit library, 16-bit data item offsets in the 16-bit
+library, and 32-bit data item offsets in the 32-bit library. <b>Note</b>: they
+are not character counts.
+</P>
+<P>
+The first pair of integers, <i>ovector[0]</i> and <i>ovector[1]</i>, identify the
+portion of the subject string matched by the entire pattern. The next pair is
+used for the first capturing subpattern, and so on. The value returned by
+<b>pcre_exec()</b> is one more than the highest numbered pair that has been set.
+For example, if two substrings have been captured, the returned value is 3. If
+there are no capturing subpatterns, the return value from a successful match is
+1, indicating that just the first pair of offsets has been set.
+</P>
+<P>
+If a capturing subpattern is matched repeatedly, it is the last portion of the
+string that it matched that is returned.
+</P>
+<P>
+If the vector is too small to hold all the captured substring offsets, it is
+used as far as possible (up to two-thirds of its length), and the function
+returns a value of zero. If neither the actual string matched nor any captured
+substrings are of interest, <b>pcre_exec()</b> may be called with <i>ovector</i>
+passed as NULL and <i>ovecsize</i> as zero. However, if the pattern contains
+back references and the <i>ovector</i> is not big enough to remember the related
+substrings, PCRE has to get additional memory for use during matching. Thus it
+is usually advisable to supply an <i>ovector</i> of reasonable size.
+</P>
+<P>
+There are some cases where zero is returned (indicating vector overflow) when
+in fact the vector is exactly the right size for the final match. For example,
+consider the pattern
+<pre>
+  (a)(?:(b)c|bd)
+</pre>
+If a vector of 6 elements (allowing for only 1 captured substring) is given
+with subject string "abd", <b>pcre_exec()</b> will try to set the second
+captured string, thereby recording a vector overflow, before failing to match
+"c" and backing up to try the second alternative. The zero return, however,
+does correctly indicate that the maximum number of slots (namely 2) have been
+filled. In similar cases where there is temporary overflow, but the final
+number of used slots is actually less than the maximum, a non-zero value is
+returned.
+</P>
+<P>
+The <b>pcre_fullinfo()</b> function can be used to find out how many capturing
+subpatterns there are in a compiled pattern. The smallest size for
+<i>ovector</i> that will allow for <i>n</i> captured substrings, in addition to
+the offsets of the substring matched by the whole pattern, is (<i>n</i>+1)*3.
+</P>
+<P>
+It is possible for capturing subpattern number <i>n+1</i> to match some part of
+the subject when subpattern <i>n</i> has not been used at all. For example, if
+the string "abc" is matched against the pattern (a|(z))(bc) the return from the
+function is 4, and subpatterns 1 and 3 are matched, but 2 is not. When this
+happens, both values in the offset pairs corresponding to unused subpatterns
+are set to -1.
+</P>
+<P>
+Offset values that correspond to unused subpatterns at the end of the
+expression are also set to -1. For example, if the string "abc" is matched
+against the pattern (abc)(x(yz)?)? subpatterns 2 and 3 are not matched. The
+return from the function is 2, because the highest used capturing subpattern
+number is 1, and the offsets for for the second and third capturing subpatterns
+(assuming the vector is large enough, of course) are set to -1.
+</P>
+<P>
+<b>Note</b>: Elements in the first two-thirds of <i>ovector</i> that do not
+correspond to capturing parentheses in the pattern are never changed. That is,
+if a pattern contains <i>n</i> capturing parentheses, no more than
+<i>ovector[0]</i> to <i>ovector[2n+1]</i> are set by <b>pcre_exec()</b>. The other
+elements (in the first two-thirds) retain whatever values they previously had.
+</P>
+<P>
+Some convenience functions are provided for extracting the captured substrings
+as separate strings. These are described below.
+<a name="errorlist"></a></P>
+<br><b>
+Error return values from <b>pcre_exec()</b>
+</b><br>
+<P>
+If <b>pcre_exec()</b> fails, it returns a negative number. The following are
+defined in the header file:
+<pre>
+  PCRE_ERROR_NOMATCH        (-1)
+</pre>
+The subject string did not match the pattern.
+<pre>
+  PCRE_ERROR_NULL           (-2)
+</pre>
+Either <i>code</i> or <i>subject</i> was passed as NULL, or <i>ovector</i> was
+NULL and <i>ovecsize</i> was not zero.
+<pre>
+  PCRE_ERROR_BADOPTION      (-3)
+</pre>
+An unrecognized bit was set in the <i>options</i> argument.
+<pre>
+  PCRE_ERROR_BADMAGIC       (-4)
+</pre>
+PCRE stores a 4-byte "magic number" at the start of the compiled code, to catch
+the case when it is passed a junk pointer and to detect when a pattern that was
+compiled in an environment of one endianness is run in an environment with the
+other endianness. This is the error that PCRE gives when the magic number is
+not present.
+<pre>
+  PCRE_ERROR_UNKNOWN_OPCODE (-5)
+</pre>
+While running the pattern match, an unknown item was encountered in the
+compiled pattern. This error could be caused by a bug in PCRE or by overwriting
+of the compiled pattern.
+<pre>
+  PCRE_ERROR_NOMEMORY       (-6)
+</pre>
+If a pattern contains back references, but the <i>ovector</i> that is passed to
+<b>pcre_exec()</b> is not big enough to remember the referenced substrings, PCRE
+gets a block of memory at the start of matching to use for this purpose. If the
+call via <b>pcre_malloc()</b> fails, this error is given. The memory is
+automatically freed at the end of matching.
+</P>
+<P>
+This error is also given if <b>pcre_stack_malloc()</b> fails in
+<b>pcre_exec()</b>. This can happen only when PCRE has been compiled with
+<b>--disable-stack-for-recursion</b>.
+<pre>
+  PCRE_ERROR_NOSUBSTRING    (-7)
+</pre>
+This error is used by the <b>pcre_copy_substring()</b>,
+<b>pcre_get_substring()</b>, and <b>pcre_get_substring_list()</b> functions (see
+below). It is never returned by <b>pcre_exec()</b>.
+<pre>
+  PCRE_ERROR_MATCHLIMIT     (-8)
+</pre>
+The backtracking limit, as specified by the <i>match_limit</i> field in a
+<b>pcre_extra</b> structure (or defaulted) was reached. See the description
+above.
+<pre>
+  PCRE_ERROR_CALLOUT        (-9)
+</pre>
+This error is never generated by <b>pcre_exec()</b> itself. It is provided for
+use by callout functions that want to yield a distinctive error code. See the
+<a href="pcrecallout.html"><b>pcrecallout</b></a>
+documentation for details.
+<pre>
+  PCRE_ERROR_BADUTF8        (-10)
+</pre>
+A string that contains an invalid UTF-8 byte sequence was passed as a subject,
+and the PCRE_NO_UTF8_CHECK option was not set. If the size of the output vector
+(<i>ovecsize</i>) is at least 2, the byte offset to the start of the the invalid
+UTF-8 character is placed in the first element, and a reason code is placed in
+the second element. The reason codes are listed in the
+<a href="#badutf8reasons">following section.</a>
+For backward compatibility, if PCRE_PARTIAL_HARD is set and the problem is a
+truncated UTF-8 character at the end of the subject (reason codes 1 to 5),
+PCRE_ERROR_SHORTUTF8 is returned instead of PCRE_ERROR_BADUTF8.
+<pre>
+  PCRE_ERROR_BADUTF8_OFFSET (-11)
+</pre>
+The UTF-8 byte sequence that was passed as a subject was checked and found to
+be valid (the PCRE_NO_UTF8_CHECK option was not set), but the value of
+<i>startoffset</i> did not point to the beginning of a UTF-8 character or the
+end of the subject.
+<pre>
+  PCRE_ERROR_PARTIAL        (-12)
+</pre>
+The subject string did not match, but it did match partially. See the
+<a href="pcrepartial.html"><b>pcrepartial</b></a>
+documentation for details of partial matching.
+<pre>
+  PCRE_ERROR_BADPARTIAL     (-13)
+</pre>
+This code is no longer in use. It was formerly returned when the PCRE_PARTIAL
+option was used with a compiled pattern containing items that were not
+supported for partial matching. From release 8.00 onwards, there are no
+restrictions on partial matching.
+<pre>
+  PCRE_ERROR_INTERNAL       (-14)
+</pre>
+An unexpected internal error has occurred. This error could be caused by a bug
+in PCRE or by overwriting of the compiled pattern.
+<pre>
+  PCRE_ERROR_BADCOUNT       (-15)
+</pre>
+This error is given if the value of the <i>ovecsize</i> argument is negative.
+<pre>
+  PCRE_ERROR_RECURSIONLIMIT (-21)
+</pre>
+The internal recursion limit, as specified by the <i>match_limit_recursion</i>
+field in a <b>pcre_extra</b> structure (or defaulted) was reached. See the
+description above.
+<pre>
+  PCRE_ERROR_BADNEWLINE     (-23)
+</pre>
+An invalid combination of PCRE_NEWLINE_<i>xxx</i> options was given.
+<pre>
+  PCRE_ERROR_BADOFFSET      (-24)
+</pre>
+The value of <i>startoffset</i> was negative or greater than the length of the
+subject, that is, the value in <i>length</i>.
+<pre>
+  PCRE_ERROR_SHORTUTF8      (-25)
+</pre>
+This error is returned instead of PCRE_ERROR_BADUTF8 when the subject string
+ends with a truncated UTF-8 character and the PCRE_PARTIAL_HARD option is set.
+Information about the failure is returned as for PCRE_ERROR_BADUTF8. It is in
+fact sufficient to detect this case, but this special error code for
+PCRE_PARTIAL_HARD precedes the implementation of returned information; it is
+retained for backwards compatibility.
+<pre>
+  PCRE_ERROR_RECURSELOOP    (-26)
+</pre>
+This error is returned when <b>pcre_exec()</b> detects a recursion loop within
+the pattern. Specifically, it means that either the whole pattern or a
+subpattern has been called recursively for the second time at the same position
+in the subject string. Some simple patterns that might do this are detected and
+faulted at compile time, but more complicated cases, in particular mutual
+recursions between two different subpatterns, cannot be detected until run
+time.
+<pre>
+  PCRE_ERROR_JIT_STACKLIMIT (-27)
+</pre>
+This error is returned when a pattern that was successfully studied using a
+JIT compile option is being matched, but the memory available for the
+just-in-time processing stack is not large enough. See the
+<a href="pcrejit.html"><b>pcrejit</b></a>
+documentation for more details.
+<pre>
+  PCRE_ERROR_BADMODE        (-28)
+</pre>
+This error is given if a pattern that was compiled by the 8-bit library is
+passed to a 16-bit or 32-bit library function, or vice versa.
+<pre>
+  PCRE_ERROR_BADENDIANNESS  (-29)
+</pre>
+This error is given if a pattern that was compiled and saved is reloaded on a
+host with different endianness. The utility function
+<b>pcre_pattern_to_host_byte_order()</b> can be used to convert such a pattern
+so that it runs on the new host.
+<pre>
+  PCRE_ERROR_JIT_BADOPTION
+</pre>
+This error is returned when a pattern that was successfully studied using a JIT
+compile option is being matched, but the matching mode (partial or complete
+match) does not correspond to any JIT compilation mode. When the JIT fast path
+function is used, this error may be also given for invalid options. See the
+<a href="pcrejit.html"><b>pcrejit</b></a>
+documentation for more details.
+<pre>
+  PCRE_ERROR_BADLENGTH      (-32)
+</pre>
+This error is given if <b>pcre_exec()</b> is called with a negative value for
+the <i>length</i> argument.
+</P>
+<P>
+Error numbers -16 to -20, -22, and 30 are not used by <b>pcre_exec()</b>.
+<a name="badutf8reasons"></a></P>
+<br><b>
+Reason codes for invalid UTF-8 strings
+</b><br>
+<P>
+This section applies only to the 8-bit library. The corresponding information
+for the 16-bit and 32-bit libraries is given in the
+<a href="pcre16.html"><b>pcre16</b></a>
+and
+<a href="pcre32.html"><b>pcre32</b></a>
+pages.
+</P>
+<P>
+When <b>pcre_exec()</b> returns either PCRE_ERROR_BADUTF8 or
+PCRE_ERROR_SHORTUTF8, and the size of the output vector (<i>ovecsize</i>) is at
+least 2, the offset of the start of the invalid UTF-8 character is placed in
+the first output vector element (<i>ovector[0]</i>) and a reason code is placed
+in the second element (<i>ovector[1]</i>). The reason codes are given names in
+the <b>pcre.h</b> header file:
+<pre>
+  PCRE_UTF8_ERR1
+  PCRE_UTF8_ERR2
+  PCRE_UTF8_ERR3
+  PCRE_UTF8_ERR4
+  PCRE_UTF8_ERR5
+</pre>
+The string ends with a truncated UTF-8 character; the code specifies how many
+bytes are missing (1 to 5). Although RFC 3629 restricts UTF-8 characters to be
+no longer than 4 bytes, the encoding scheme (originally defined by RFC 2279)
+allows for up to 6 bytes, and this is checked first; hence the possibility of
+4 or 5 missing bytes.
+<pre>
+  PCRE_UTF8_ERR6
+  PCRE_UTF8_ERR7
+  PCRE_UTF8_ERR8
+  PCRE_UTF8_ERR9
+  PCRE_UTF8_ERR10
+</pre>
+The two most significant bits of the 2nd, 3rd, 4th, 5th, or 6th byte of the
+character do not have the binary value 0b10 (that is, either the most
+significant bit is 0, or the next bit is 1).
+<pre>
+  PCRE_UTF8_ERR11
+  PCRE_UTF8_ERR12
+</pre>
+A character that is valid by the RFC 2279 rules is either 5 or 6 bytes long;
+these code points are excluded by RFC 3629.
+<pre>
+  PCRE_UTF8_ERR13
+</pre>
+A 4-byte character has a value greater than 0x10fff; these code points are
+excluded by RFC 3629.
+<pre>
+  PCRE_UTF8_ERR14
+</pre>
+A 3-byte character has a value in the range 0xd800 to 0xdfff; this range of
+code points are reserved by RFC 3629 for use with UTF-16, and so are excluded
+from UTF-8.
+<pre>
+  PCRE_UTF8_ERR15
+  PCRE_UTF8_ERR16
+  PCRE_UTF8_ERR17
+  PCRE_UTF8_ERR18
+  PCRE_UTF8_ERR19
+</pre>
+A 2-, 3-, 4-, 5-, or 6-byte character is "overlong", that is, it codes for a
+value that can be represented by fewer bytes, which is invalid. For example,
+the two bytes 0xc0, 0xae give the value 0x2e, whose correct coding uses just
+one byte.
+<pre>
+  PCRE_UTF8_ERR20
+</pre>
+The two most significant bits of the first byte of a character have the binary
+value 0b10 (that is, the most significant bit is 1 and the second is 0). Such a
+byte can only validly occur as the second or subsequent byte of a multi-byte
+character.
+<pre>
+  PCRE_UTF8_ERR21
+</pre>
+The first byte of a character has the value 0xfe or 0xff. These values can
+never occur in a valid UTF-8 string.
+<pre>
+  PCRE_UTF8_ERR22
+</pre>
+This error code was formerly used when the presence of a so-called
+"non-character" caused an error. Unicode corrigendum #9 makes it clear that
+such characters should not cause a string to be rejected, and so this code is
+no longer in use and is never returned.
+</P>
+<br><a name="SEC18" href="#TOC1">EXTRACTING CAPTURED SUBSTRINGS BY NUMBER</a><br>
+<P>
+<b>int pcre_copy_substring(const char *<i>subject</i>, int *<i>ovector</i>,</b>
+<b>     int <i>stringcount</i>, int <i>stringnumber</i>, char *<i>buffer</i>,</b>
+<b>     int <i>buffersize</i>);</b>
+<br>
+<br>
+<b>int pcre_get_substring(const char *<i>subject</i>, int *<i>ovector</i>,</b>
+<b>     int <i>stringcount</i>, int <i>stringnumber</i>,</b>
+<b>     const char **<i>stringptr</i>);</b>
+<br>
+<br>
+<b>int pcre_get_substring_list(const char *<i>subject</i>,</b>
+<b>     int *<i>ovector</i>, int <i>stringcount</i>, const char ***<i>listptr</i>);</b>
+</P>
+<P>
+Captured substrings can be accessed directly by using the offsets returned by
+<b>pcre_exec()</b> in <i>ovector</i>. For convenience, the functions
+<b>pcre_copy_substring()</b>, <b>pcre_get_substring()</b>, and
+<b>pcre_get_substring_list()</b> are provided for extracting captured substrings
+as new, separate, zero-terminated strings. These functions identify substrings
+by number. The next section describes functions for extracting named
+substrings.
+</P>
+<P>
+A substring that contains a binary zero is correctly extracted and has a
+further zero added on the end, but the result is not, of course, a C string.
+However, you can process such a string by referring to the length that is
+returned by <b>pcre_copy_substring()</b> and <b>pcre_get_substring()</b>.
+Unfortunately, the interface to <b>pcre_get_substring_list()</b> is not adequate
+for handling strings containing binary zeros, because the end of the final
+string is not independently indicated.
+</P>
+<P>
+The first three arguments are the same for all three of these functions:
+<i>subject</i> is the subject string that has just been successfully matched,
+<i>ovector</i> is a pointer to the vector of integer offsets that was passed to
+<b>pcre_exec()</b>, and <i>stringcount</i> is the number of substrings that were
+captured by the match, including the substring that matched the entire regular
+expression. This is the value returned by <b>pcre_exec()</b> if it is greater
+than zero. If <b>pcre_exec()</b> returned zero, indicating that it ran out of
+space in <i>ovector</i>, the value passed as <i>stringcount</i> should be the
+number of elements in the vector divided by three.
+</P>
+<P>
+The functions <b>pcre_copy_substring()</b> and <b>pcre_get_substring()</b>
+extract a single substring, whose number is given as <i>stringnumber</i>. A
+value of zero extracts the substring that matched the entire pattern, whereas
+higher values extract the captured substrings. For <b>pcre_copy_substring()</b>,
+the string is placed in <i>buffer</i>, whose length is given by
+<i>buffersize</i>, while for <b>pcre_get_substring()</b> a new block of memory is
+obtained via <b>pcre_malloc</b>, and its address is returned via
+<i>stringptr</i>. The yield of the function is the length of the string, not
+including the terminating zero, or one of these error codes:
+<pre>
+  PCRE_ERROR_NOMEMORY       (-6)
+</pre>
+The buffer was too small for <b>pcre_copy_substring()</b>, or the attempt to get
+memory failed for <b>pcre_get_substring()</b>.
+<pre>
+  PCRE_ERROR_NOSUBSTRING    (-7)
+</pre>
+There is no substring whose number is <i>stringnumber</i>.
+</P>
+<P>
+The <b>pcre_get_substring_list()</b> function extracts all available substrings
+and builds a list of pointers to them. All this is done in a single block of
+memory that is obtained via <b>pcre_malloc</b>. The address of the memory block
+is returned via <i>listptr</i>, which is also the start of the list of string
+pointers. The end of the list is marked by a NULL pointer. The yield of the
+function is zero if all went well, or the error code
+<pre>
+  PCRE_ERROR_NOMEMORY       (-6)
+</pre>
+if the attempt to get the memory block failed.
+</P>
+<P>
+When any of these functions encounter a substring that is unset, which can
+happen when capturing subpattern number <i>n+1</i> matches some part of the
+subject, but subpattern <i>n</i> has not been used at all, they return an empty
+string. This can be distinguished from a genuine zero-length substring by
+inspecting the appropriate offset in <i>ovector</i>, which is negative for unset
+substrings.
+</P>
+<P>
+The two convenience functions <b>pcre_free_substring()</b> and
+<b>pcre_free_substring_list()</b> can be used to free the memory returned by
+a previous call of <b>pcre_get_substring()</b> or
+<b>pcre_get_substring_list()</b>, respectively. They do nothing more than call
+the function pointed to by <b>pcre_free</b>, which of course could be called
+directly from a C program. However, PCRE is used in some situations where it is
+linked via a special interface to another programming language that cannot use
+<b>pcre_free</b> directly; it is for these cases that the functions are
+provided.
+</P>
+<br><a name="SEC19" href="#TOC1">EXTRACTING CAPTURED SUBSTRINGS BY NAME</a><br>
+<P>
+<b>int pcre_get_stringnumber(const pcre *<i>code</i>,</b>
+<b>     const char *<i>name</i>);</b>
+<br>
+<br>
+<b>int pcre_copy_named_substring(const pcre *<i>code</i>,</b>
+<b>     const char *<i>subject</i>, int *<i>ovector</i>,</b>
+<b>     int <i>stringcount</i>, const char *<i>stringname</i>,</b>
+<b>     char *<i>buffer</i>, int <i>buffersize</i>);</b>
+<br>
+<br>
+<b>int pcre_get_named_substring(const pcre *<i>code</i>,</b>
+<b>     const char *<i>subject</i>, int *<i>ovector</i>,</b>
+<b>     int <i>stringcount</i>, const char *<i>stringname</i>,</b>
+<b>     const char **<i>stringptr</i>);</b>
+</P>
+<P>
+To extract a substring by name, you first have to find associated number.
+For example, for this pattern
+<pre>
+  (a+)b(?&#60;xxx&#62;\d+)...
+</pre>
+the number of the subpattern called "xxx" is 2. If the name is known to be
+unique (PCRE_DUPNAMES was not set), you can find the number from the name by
+calling <b>pcre_get_stringnumber()</b>. The first argument is the compiled
+pattern, and the second is the name. The yield of the function is the
+subpattern number, or PCRE_ERROR_NOSUBSTRING (-7) if there is no subpattern of
+that name.
+</P>
+<P>
+Given the number, you can extract the substring directly, or use one of the
+functions described in the previous section. For convenience, there are also
+two functions that do the whole job.
+</P>
+<P>
+Most of the arguments of <b>pcre_copy_named_substring()</b> and
+<b>pcre_get_named_substring()</b> are the same as those for the similarly named
+functions that extract by number. As these are described in the previous
+section, they are not re-described here. There are just two differences:
+</P>
+<P>
+First, instead of a substring number, a substring name is given. Second, there
+is an extra argument, given at the start, which is a pointer to the compiled
+pattern. This is needed in order to gain access to the name-to-number
+translation table.
+</P>
+<P>
+These functions call <b>pcre_get_stringnumber()</b>, and if it succeeds, they
+then call <b>pcre_copy_substring()</b> or <b>pcre_get_substring()</b>, as
+appropriate. <b>NOTE:</b> If PCRE_DUPNAMES is set and there are duplicate names,
+the behaviour may not be what you want (see the next section).
+</P>
+<P>
+<b>Warning:</b> If the pattern uses the (?| feature to set up multiple
+subpatterns with the same number, as described in the
+<a href="pcrepattern.html#dupsubpatternnumber">section on duplicate subpattern numbers</a>
+in the
+<a href="pcrepattern.html"><b>pcrepattern</b></a>
+page, you cannot use names to distinguish the different subpatterns, because
+names are not included in the compiled code. The matching process uses only
+numbers. For this reason, the use of different names for subpatterns of the
+same number causes an error at compile time.
+</P>
+<br><a name="SEC20" href="#TOC1">DUPLICATE SUBPATTERN NAMES</a><br>
+<P>
+<b>int pcre_get_stringtable_entries(const pcre *<i>code</i>,</b>
+<b>     const char *<i>name</i>, char **<i>first</i>, char **<i>last</i>);</b>
+</P>
+<P>
+When a pattern is compiled with the PCRE_DUPNAMES option, names for subpatterns
+are not required to be unique. (Duplicate names are always allowed for
+subpatterns with the same number, created by using the (?| feature. Indeed, if
+such subpatterns are named, they are required to use the same names.)
+</P>
+<P>
+Normally, patterns with duplicate names are such that in any one match, only
+one of the named subpatterns participates. An example is shown in the
+<a href="pcrepattern.html"><b>pcrepattern</b></a>
+documentation.
+</P>
+<P>
+When duplicates are present, <b>pcre_copy_named_substring()</b> and
+<b>pcre_get_named_substring()</b> return the first substring corresponding to
+the given name that is set. If none are set, PCRE_ERROR_NOSUBSTRING (-7) is
+returned; no data is returned. The <b>pcre_get_stringnumber()</b> function
+returns one of the numbers that are associated with the name, but it is not
+defined which it is.
+</P>
+<P>
+If you want to get full details of all captured substrings for a given name,
+you must use the <b>pcre_get_stringtable_entries()</b> function. The first
+argument is the compiled pattern, and the second is the name. The third and
+fourth are pointers to variables which are updated by the function. After it
+has run, they point to the first and last entries in the name-to-number table
+for the given name. The function itself returns the length of each entry, or
+PCRE_ERROR_NOSUBSTRING (-7) if there are none. The format of the table is
+described above in the section entitled <i>Information about a pattern</i>
+<a href="#infoaboutpattern">above.</a>
+Given all the relevant entries for the name, you can extract each of their
+numbers, and hence the captured data, if any.
+</P>
+<br><a name="SEC21" href="#TOC1">FINDING ALL POSSIBLE MATCHES</a><br>
+<P>
+The traditional matching function uses a similar algorithm to Perl, which stops
+when it finds the first match, starting at a given point in the subject. If you
+want to find all possible matches, or the longest possible match, consider
+using the alternative matching function (see below) instead. If you cannot use
+the alternative function, but still need to find all possible matches, you
+can kludge it up by making use of the callout facility, which is described in
+the
+<a href="pcrecallout.html"><b>pcrecallout</b></a>
+documentation.
+</P>
+<P>
+What you have to do is to insert a callout right at the end of the pattern.
+When your callout function is called, extract and save the current matched
+substring. Then return 1, which forces <b>pcre_exec()</b> to backtrack and try
+other alternatives. Ultimately, when it runs out of matches, <b>pcre_exec()</b>
+will yield PCRE_ERROR_NOMATCH.
+</P>
+<br><a name="SEC22" href="#TOC1">OBTAINING AN ESTIMATE OF STACK USAGE</a><br>
+<P>
+Matching certain patterns using <b>pcre_exec()</b> can use a lot of process
+stack, which in certain environments can be rather limited in size. Some users
+find it helpful to have an estimate of the amount of stack that is used by
+<b>pcre_exec()</b>, to help them set recursion limits, as described in the
+<a href="pcrestack.html"><b>pcrestack</b></a>
+documentation. The estimate that is output by <b>pcretest</b> when called with
+the <b>-m</b> and <b>-C</b> options is obtained by calling <b>pcre_exec</b> with
+the values NULL, NULL, NULL, -999, and -999 for its first five arguments.
+</P>
+<P>
+Normally, if its first argument is NULL, <b>pcre_exec()</b> immediately returns
+the negative error code PCRE_ERROR_NULL, but with this special combination of
+arguments, it returns instead a negative number whose absolute value is the
+approximate stack frame size in bytes. (A negative number is used so that it is
+clear that no match has happened.) The value is approximate because in some
+cases, recursive calls to <b>pcre_exec()</b> occur when there are one or two
+additional variables on the stack.
+</P>
+<P>
+If PCRE has been compiled to use the heap instead of the stack for recursion,
+the value returned is the size of each block that is obtained from the heap.
+<a name="dfamatch"></a></P>
+<br><a name="SEC23" href="#TOC1">MATCHING A PATTERN: THE ALTERNATIVE FUNCTION</a><br>
+<P>
+<b>int pcre_dfa_exec(const pcre *<i>code</i>, const pcre_extra *<i>extra</i>,</b>
+<b>     const char *<i>subject</i>, int <i>length</i>, int <i>startoffset</i>,</b>
+<b>     int <i>options</i>, int *<i>ovector</i>, int <i>ovecsize</i>,</b>
+<b>     int *<i>workspace</i>, int <i>wscount</i>);</b>
+</P>
+<P>
+The function <b>pcre_dfa_exec()</b> is called to match a subject string against
+a compiled pattern, using a matching algorithm that scans the subject string
+just once, and does not backtrack. This has different characteristics to the
+normal algorithm, and is not compatible with Perl. Some of the features of PCRE
+patterns are not supported. Nevertheless, there are times when this kind of
+matching can be useful. For a discussion of the two matching algorithms, and a
+list of features that <b>pcre_dfa_exec()</b> does not support, see the
+<a href="pcrematching.html"><b>pcrematching</b></a>
+documentation.
+</P>
+<P>
+The arguments for the <b>pcre_dfa_exec()</b> function are the same as for
+<b>pcre_exec()</b>, plus two extras. The <i>ovector</i> argument is used in a
+different way, and this is described below. The other common arguments are used
+in the same way as for <b>pcre_exec()</b>, so their description is not repeated
+here.
+</P>
+<P>
+The two additional arguments provide workspace for the function. The workspace
+vector should contain at least 20 elements. It is used for keeping track of
+multiple paths through the pattern tree. More workspace will be needed for
+patterns and subjects where there are a lot of potential matches.
+</P>
+<P>
+Here is an example of a simple call to <b>pcre_dfa_exec()</b>:
+<pre>
+  int rc;
+  int ovector[10];
+  int wspace[20];
+  rc = pcre_dfa_exec(
+    re,             /* result of pcre_compile() */
+    NULL,           /* we didn't study the pattern */
+    "some string",  /* the subject string */
+    11,             /* the length of the subject string */
+    0,              /* start at offset 0 in the subject */
+    0,              /* default options */
+    ovector,        /* vector of integers for substring information */
+    10,             /* number of elements (NOT size in bytes) */
+    wspace,         /* working space vector */
+    20);            /* number of elements (NOT size in bytes) */
+</PRE>
+</P>
+<br><b>
+Option bits for <b>pcre_dfa_exec()</b>
+</b><br>
+<P>
+The unused bits of the <i>options</i> argument for <b>pcre_dfa_exec()</b> must be
+zero. The only bits that may be set are PCRE_ANCHORED, PCRE_NEWLINE_<i>xxx</i>,
+PCRE_NOTBOL, PCRE_NOTEOL, PCRE_NOTEMPTY, PCRE_NOTEMPTY_ATSTART,
+PCRE_NO_UTF8_CHECK, PCRE_BSR_ANYCRLF, PCRE_BSR_UNICODE, PCRE_NO_START_OPTIMIZE,
+PCRE_PARTIAL_HARD, PCRE_PARTIAL_SOFT, PCRE_DFA_SHORTEST, and PCRE_DFA_RESTART.
+All but the last four of these are exactly the same as for <b>pcre_exec()</b>,
+so their description is not repeated here.
+<pre>
+  PCRE_PARTIAL_HARD
+  PCRE_PARTIAL_SOFT
+</pre>
+These have the same general effect as they do for <b>pcre_exec()</b>, but the
+details are slightly different. When PCRE_PARTIAL_HARD is set for
+<b>pcre_dfa_exec()</b>, it returns PCRE_ERROR_PARTIAL if the end of the subject
+is reached and there is still at least one matching possibility that requires
+additional characters. This happens even if some complete matches have also
+been found. When PCRE_PARTIAL_SOFT is set, the return code PCRE_ERROR_NOMATCH
+is converted into PCRE_ERROR_PARTIAL if the end of the subject is reached,
+there have been no complete matches, but there is still at least one matching
+possibility. The portion of the string that was inspected when the longest
+partial match was found is set as the first matching string in both cases.
+There is a more detailed discussion of partial and multi-segment matching, with
+examples, in the
+<a href="pcrepartial.html"><b>pcrepartial</b></a>
+documentation.
+<pre>
+  PCRE_DFA_SHORTEST
+</pre>
+Setting the PCRE_DFA_SHORTEST option causes the matching algorithm to stop as
+soon as it has found one match. Because of the way the alternative algorithm
+works, this is necessarily the shortest possible match at the first possible
+matching point in the subject string.
+<pre>
+  PCRE_DFA_RESTART
+</pre>
+When <b>pcre_dfa_exec()</b> returns a partial match, it is possible to call it
+again, with additional subject characters, and have it continue with the same
+match. The PCRE_DFA_RESTART option requests this action; when it is set, the
+<i>workspace</i> and <i>wscount</i> options must reference the same vector as
+before because data about the match so far is left in them after a partial
+match. There is more discussion of this facility in the
+<a href="pcrepartial.html"><b>pcrepartial</b></a>
+documentation.
+</P>
+<br><b>
+Successful returns from <b>pcre_dfa_exec()</b>
+</b><br>
+<P>
+When <b>pcre_dfa_exec()</b> succeeds, it may have matched more than one
+substring in the subject. Note, however, that all the matches from one run of
+the function start at the same point in the subject. The shorter matches are
+all initial substrings of the longer matches. For example, if the pattern
+<pre>
+  &#60;.*&#62;
+</pre>
+is matched against the string
+<pre>
+  This is &#60;something&#62; &#60;something else&#62; &#60;something further&#62; no more
+</pre>
+the three matched strings are
+<pre>
+  &#60;something&#62;
+  &#60;something&#62; &#60;something else&#62;
+  &#60;something&#62; &#60;something else&#62; &#60;something further&#62;
+</pre>
+On success, the yield of the function is a number greater than zero, which is
+the number of matched substrings. The substrings themselves are returned in
+<i>ovector</i>. Each string uses two elements; the first is the offset to the
+start, and the second is the offset to the end. In fact, all the strings have
+the same start offset. (Space could have been saved by giving this only once,
+but it was decided to retain some compatibility with the way <b>pcre_exec()</b>
+returns data, even though the meaning of the strings is different.)
+</P>
+<P>
+The strings are returned in reverse order of length; that is, the longest
+matching string is given first. If there were too many matches to fit into
+<i>ovector</i>, the yield of the function is zero, and the vector is filled with
+the longest matches. Unlike <b>pcre_exec()</b>, <b>pcre_dfa_exec()</b> can use
+the entire <i>ovector</i> for returning matched strings.
+</P>
+<P>
+NOTE: PCRE's "auto-possessification" optimization usually applies to character
+repeats at the end of a pattern (as well as internally). For example, the
+pattern "a\d+" is compiled as if it were "a\d++" because there is no point
+even considering the possibility of backtracking into the repeated digits. For
+DFA matching, this means that only one possible match is found. If you really
+do want multiple matches in such cases, either use an ungreedy repeat
+("a\d+?") or set the PCRE_NO_AUTO_POSSESS option when compiling.
+</P>
+<br><b>
+Error returns from <b>pcre_dfa_exec()</b>
+</b><br>
+<P>
+The <b>pcre_dfa_exec()</b> function returns a negative number when it fails.
+Many of the errors are the same as for <b>pcre_exec()</b>, and these are
+described
+<a href="#errorlist">above.</a>
+There are in addition the following errors that are specific to
+<b>pcre_dfa_exec()</b>:
+<pre>
+  PCRE_ERROR_DFA_UITEM      (-16)
+</pre>
+This return is given if <b>pcre_dfa_exec()</b> encounters an item in the pattern
+that it does not support, for instance, the use of \C or a back reference.
+<pre>
+  PCRE_ERROR_DFA_UCOND      (-17)
+</pre>
+This return is given if <b>pcre_dfa_exec()</b> encounters a condition item that
+uses a back reference for the condition, or a test for recursion in a specific
+group. These are not supported.
+<pre>
+  PCRE_ERROR_DFA_UMLIMIT    (-18)
+</pre>
+This return is given if <b>pcre_dfa_exec()</b> is called with an <i>extra</i>
+block that contains a setting of the <i>match_limit</i> or
+<i>match_limit_recursion</i> fields. This is not supported (these fields are
+meaningless for DFA matching).
+<pre>
+  PCRE_ERROR_DFA_WSSIZE     (-19)
+</pre>
+This return is given if <b>pcre_dfa_exec()</b> runs out of space in the
+<i>workspace</i> vector.
+<pre>
+  PCRE_ERROR_DFA_RECURSE    (-20)
+</pre>
+When a recursive subpattern is processed, the matching function calls itself
+recursively, using private vectors for <i>ovector</i> and <i>workspace</i>. This
+error is given if the output vector is not large enough. This should be
+extremely rare, as a vector of size 1000 is used.
+<pre>
+  PCRE_ERROR_DFA_BADRESTART (-30)
+</pre>
+When <b>pcre_dfa_exec()</b> is called with the <b>PCRE_DFA_RESTART</b> option,
+some plausibility checks are made on the contents of the workspace, which
+should contain data about the previous partial match. If any of these checks
+fail, this error is given.
+</P>
+<br><a name="SEC24" href="#TOC1">SEE ALSO</a><br>
+<P>
+<b>pcre16</b>(3), <b>pcre32</b>(3), <b>pcrebuild</b>(3), <b>pcrecallout</b>(3),
+<b>pcrecpp(3)</b>(3), <b>pcrematching</b>(3), <b>pcrepartial</b>(3),
+<b>pcreposix</b>(3), <b>pcreprecompile</b>(3), <b>pcresample</b>(3),
+<b>pcrestack</b>(3).
+</P>
+<br><a name="SEC25" href="#TOC1">AUTHOR</a><br>
+<P>
+Philip Hazel
+<br>
+University Computing Service
+<br>
+Cambridge CB2 3QH, England.
+<br>
+</P>
+<br><a name="SEC26" href="#TOC1">REVISION</a><br>
+<P>
+Last updated: 09 February 2014
+<br>
+Copyright &copy; 1997-2014 University of Cambridge.
+<br>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcrebuild.html b/libs/Pcre16/docs/doc/html/pcrebuild.html
new file mode 100644
index 0000000000..03c8cbe0b2
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcrebuild.html
@@ -0,0 +1,534 @@
+<html>
+<head>
+<title>pcrebuild specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcrebuild man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<ul>
+<li><a name="TOC1" href="#SEC1">BUILDING PCRE</a>
+<li><a name="TOC2" href="#SEC2">PCRE BUILD-TIME OPTIONS</a>
+<li><a name="TOC3" href="#SEC3">BUILDING 8-BIT, 16-BIT AND 32-BIT LIBRARIES</a>
+<li><a name="TOC4" href="#SEC4">BUILDING SHARED AND STATIC LIBRARIES</a>
+<li><a name="TOC5" href="#SEC5">C++ SUPPORT</a>
+<li><a name="TOC6" href="#SEC6">UTF-8, UTF-16 AND UTF-32 SUPPORT</a>
+<li><a name="TOC7" href="#SEC7">UNICODE CHARACTER PROPERTY SUPPORT</a>
+<li><a name="TOC8" href="#SEC8">JUST-IN-TIME COMPILER SUPPORT</a>
+<li><a name="TOC9" href="#SEC9">CODE VALUE OF NEWLINE</a>
+<li><a name="TOC10" href="#SEC10">WHAT \R MATCHES</a>
+<li><a name="TOC11" href="#SEC11">POSIX MALLOC USAGE</a>
+<li><a name="TOC12" href="#SEC12">HANDLING VERY LARGE PATTERNS</a>
+<li><a name="TOC13" href="#SEC13">AVOIDING EXCESSIVE STACK USAGE</a>
+<li><a name="TOC14" href="#SEC14">LIMITING PCRE RESOURCE USAGE</a>
+<li><a name="TOC15" href="#SEC15">CREATING CHARACTER TABLES AT BUILD TIME</a>
+<li><a name="TOC16" href="#SEC16">USING EBCDIC CODE</a>
+<li><a name="TOC17" href="#SEC17">PCREGREP OPTIONS FOR COMPRESSED FILE SUPPORT</a>
+<li><a name="TOC18" href="#SEC18">PCREGREP BUFFER SIZE</a>
+<li><a name="TOC19" href="#SEC19">PCRETEST OPTION FOR LIBREADLINE SUPPORT</a>
+<li><a name="TOC20" href="#SEC20">DEBUGGING WITH VALGRIND SUPPORT</a>
+<li><a name="TOC21" href="#SEC21">CODE COVERAGE REPORTING</a>
+<li><a name="TOC22" href="#SEC22">SEE ALSO</a>
+<li><a name="TOC23" href="#SEC23">AUTHOR</a>
+<li><a name="TOC24" href="#SEC24">REVISION</a>
+</ul>
+<br><a name="SEC1" href="#TOC1">BUILDING PCRE</a><br>
+<P>
+PCRE is distributed with a <b>configure</b> script that can be used to build the
+library in Unix-like environments using the applications known as Autotools.
+Also in the distribution are files to support building using <b>CMake</b>
+instead of <b>configure</b>. The text file
+<a href="README.txt"><b>README</b></a>
+contains general information about building with Autotools (some of which is
+repeated below), and also has some comments about building on various operating
+systems. There is a lot more information about building PCRE without using
+Autotools (including information about using <b>CMake</b> and building "by
+hand") in the text file called
+<a href="NON-AUTOTOOLS-BUILD.txt"><b>NON-AUTOTOOLS-BUILD</b>.</a>
+You should consult this file as well as the
+<a href="README.txt"><b>README</b></a>
+file if you are building in a non-Unix-like environment.
+</P>
+<br><a name="SEC2" href="#TOC1">PCRE BUILD-TIME OPTIONS</a><br>
+<P>
+The rest of this document describes the optional features of PCRE that can be
+selected when the library is compiled. It assumes use of the <b>configure</b>
+script, where the optional features are selected or deselected by providing
+options to <b>configure</b> before running the <b>make</b> command. However, the
+same options can be selected in both Unix-like and non-Unix-like environments
+using the GUI facility of <b>cmake-gui</b> if you are using <b>CMake</b> instead
+of <b>configure</b> to build PCRE.
+</P>
+<P>
+If you are not using Autotools or <b>CMake</b>, option selection can be done by
+editing the <b>config.h</b> file, or by passing parameter settings to the
+compiler, as described in
+<a href="NON-AUTOTOOLS-BUILD.txt"><b>NON-AUTOTOOLS-BUILD</b>.</a>
+</P>
+<P>
+The complete list of options for <b>configure</b> (which includes the standard
+ones such as the selection of the installation directory) can be obtained by
+running
+<pre>
+  ./configure --help
+</pre>
+The following sections include descriptions of options whose names begin with
+--enable or --disable. These settings specify changes to the defaults for the
+<b>configure</b> command. Because of the way that <b>configure</b> works,
+--enable and --disable always come in pairs, so the complementary option always
+exists as well, but as it specifies the default, it is not described.
+</P>
+<br><a name="SEC3" href="#TOC1">BUILDING 8-BIT, 16-BIT AND 32-BIT LIBRARIES</a><br>
+<P>
+By default, a library called <b>libpcre</b> is built, containing functions that
+take string arguments contained in vectors of bytes, either as single-byte
+characters, or interpreted as UTF-8 strings. You can also build a separate
+library, called <b>libpcre16</b>, in which strings are contained in vectors of
+16-bit data units and interpreted either as single-unit characters or UTF-16
+strings, by adding
+<pre>
+  --enable-pcre16
+</pre>
+to the <b>configure</b> command. You can also build yet another separate
+library, called <b>libpcre32</b>, in which strings are contained in vectors of
+32-bit data units and interpreted either as single-unit characters or UTF-32
+strings, by adding
+<pre>
+  --enable-pcre32
+</pre>
+to the <b>configure</b> command. If you do not want the 8-bit library, add
+<pre>
+  --disable-pcre8
+</pre>
+as well. At least one of the three libraries must be built. Note that the C++
+and POSIX wrappers are for the 8-bit library only, and that <b>pcregrep</b> is
+an 8-bit program. None of these are built if you select only the 16-bit or
+32-bit libraries.
+</P>
+<br><a name="SEC4" href="#TOC1">BUILDING SHARED AND STATIC LIBRARIES</a><br>
+<P>
+The Autotools PCRE building process uses <b>libtool</b> to build both shared and
+static libraries by default. You can suppress one of these by adding one of
+<pre>
+  --disable-shared
+  --disable-static
+</pre>
+to the <b>configure</b> command, as required.
+</P>
+<br><a name="SEC5" href="#TOC1">C++ SUPPORT</a><br>
+<P>
+By default, if the 8-bit library is being built, the <b>configure</b> script
+will search for a C++ compiler and C++ header files. If it finds them, it
+automatically builds the C++ wrapper library (which supports only 8-bit
+strings). You can disable this by adding
+<pre>
+  --disable-cpp
+</pre>
+to the <b>configure</b> command.
+</P>
+<br><a name="SEC6" href="#TOC1">UTF-8, UTF-16 AND UTF-32 SUPPORT</a><br>
+<P>
+To build PCRE with support for UTF Unicode character strings, add
+<pre>
+  --enable-utf
+</pre>
+to the <b>configure</b> command. This setting applies to all three libraries,
+adding support for UTF-8 to the 8-bit library, support for UTF-16 to the 16-bit
+library, and support for UTF-32 to the to the 32-bit library. There are no
+separate options for enabling UTF-8, UTF-16 and UTF-32 independently because
+that would allow ridiculous settings such as requesting UTF-16 support while
+building only the 8-bit library. It is not possible to build one library with
+UTF support and another without in the same configuration. (For backwards
+compatibility, --enable-utf8 is a synonym of --enable-utf.)
+</P>
+<P>
+Of itself, this setting does not make PCRE treat strings as UTF-8, UTF-16 or
+UTF-32. As well as compiling PCRE with this option, you also have have to set
+the PCRE_UTF8, PCRE_UTF16 or PCRE_UTF32 option (as appropriate) when you call
+one of the pattern compiling functions.
+</P>
+<P>
+If you set --enable-utf when compiling in an EBCDIC environment, PCRE expects
+its input to be either ASCII or UTF-8 (depending on the run-time option). It is
+not possible to support both EBCDIC and UTF-8 codes in the same version of the
+library. Consequently, --enable-utf and --enable-ebcdic are mutually
+exclusive.
+</P>
+<br><a name="SEC7" href="#TOC1">UNICODE CHARACTER PROPERTY SUPPORT</a><br>
+<P>
+UTF support allows the libraries to process character codepoints up to 0x10ffff
+in the strings that they handle. On its own, however, it does not provide any
+facilities for accessing the properties of such characters. If you want to be
+able to use the pattern escapes \P, \p, and \X, which refer to Unicode
+character properties, you must add
+<pre>
+  --enable-unicode-properties
+</pre>
+to the <b>configure</b> command. This implies UTF support, even if you have
+not explicitly requested it.
+</P>
+<P>
+Including Unicode property support adds around 30K of tables to the PCRE
+library. Only the general category properties such as <i>Lu</i> and <i>Nd</i> are
+supported. Details are given in the
+<a href="pcrepattern.html"><b>pcrepattern</b></a>
+documentation.
+</P>
+<br><a name="SEC8" href="#TOC1">JUST-IN-TIME COMPILER SUPPORT</a><br>
+<P>
+Just-in-time compiler support is included in the build by specifying
+<pre>
+  --enable-jit
+</pre>
+This support is available only for certain hardware architectures. If this
+option is set for an unsupported architecture, a compile time error occurs.
+See the
+<a href="pcrejit.html"><b>pcrejit</b></a>
+documentation for a discussion of JIT usage. When JIT support is enabled,
+pcregrep automatically makes use of it, unless you add
+<pre>
+  --disable-pcregrep-jit
+</pre>
+to the "configure" command.
+</P>
+<br><a name="SEC9" href="#TOC1">CODE VALUE OF NEWLINE</a><br>
+<P>
+By default, PCRE interprets the linefeed (LF) character as indicating the end
+of a line. This is the normal newline character on Unix-like systems. You can
+compile PCRE to use carriage return (CR) instead, by adding
+<pre>
+  --enable-newline-is-cr
+</pre>
+to the <b>configure</b> command. There is also a --enable-newline-is-lf option,
+which explicitly specifies linefeed as the newline character.
+<br>
+<br>
+Alternatively, you can specify that line endings are to be indicated by the two
+character sequence CRLF. If you want this, add
+<pre>
+  --enable-newline-is-crlf
+</pre>
+to the <b>configure</b> command. There is a fourth option, specified by
+<pre>
+  --enable-newline-is-anycrlf
+</pre>
+which causes PCRE to recognize any of the three sequences CR, LF, or CRLF as
+indicating a line ending. Finally, a fifth option, specified by
+<pre>
+  --enable-newline-is-any
+</pre>
+causes PCRE to recognize any Unicode newline sequence.
+</P>
+<P>
+Whatever line ending convention is selected when PCRE is built can be
+overridden when the library functions are called. At build time it is
+conventional to use the standard for your operating system.
+</P>
+<br><a name="SEC10" href="#TOC1">WHAT \R MATCHES</a><br>
+<P>
+By default, the sequence \R in a pattern matches any Unicode newline sequence,
+whatever has been selected as the line ending sequence. If you specify
+<pre>
+  --enable-bsr-anycrlf
+</pre>
+the default is changed so that \R matches only CR, LF, or CRLF. Whatever is
+selected when PCRE is built can be overridden when the library functions are
+called.
+</P>
+<br><a name="SEC11" href="#TOC1">POSIX MALLOC USAGE</a><br>
+<P>
+When the 8-bit library is called through the POSIX interface (see the
+<a href="pcreposix.html"><b>pcreposix</b></a>
+documentation), additional working storage is required for holding the pointers
+to capturing substrings, because PCRE requires three integers per substring,
+whereas the POSIX interface provides only two. If the number of expected
+substrings is small, the wrapper function uses space on the stack, because this
+is faster than using <b>malloc()</b> for each call. The default threshold above
+which the stack is no longer used is 10; it can be changed by adding a setting
+such as
+<pre>
+  --with-posix-malloc-threshold=20
+</pre>
+to the <b>configure</b> command.
+</P>
+<br><a name="SEC12" href="#TOC1">HANDLING VERY LARGE PATTERNS</a><br>
+<P>
+Within a compiled pattern, offset values are used to point from one part to
+another (for example, from an opening parenthesis to an alternation
+metacharacter). By default, in the 8-bit and 16-bit libraries, two-byte values
+are used for these offsets, leading to a maximum size for a compiled pattern of
+around 64K. This is sufficient to handle all but the most gigantic patterns.
+Nevertheless, some people do want to process truly enormous patterns, so it is
+possible to compile PCRE to use three-byte or four-byte offsets by adding a
+setting such as
+<pre>
+  --with-link-size=3
+</pre>
+to the <b>configure</b> command. The value given must be 2, 3, or 4. For the
+16-bit library, a value of 3 is rounded up to 4. In these libraries, using
+longer offsets slows down the operation of PCRE because it has to load
+additional data when handling them. For the 32-bit library the value is always
+4 and cannot be overridden; the value of --with-link-size is ignored.
+</P>
+<br><a name="SEC13" href="#TOC1">AVOIDING EXCESSIVE STACK USAGE</a><br>
+<P>
+When matching with the <b>pcre_exec()</b> function, PCRE implements backtracking
+by making recursive calls to an internal function called <b>match()</b>. In
+environments where the size of the stack is limited, this can severely limit
+PCRE's operation. (The Unix environment does not usually suffer from this
+problem, but it may sometimes be necessary to increase the maximum stack size.
+There is a discussion in the
+<a href="pcrestack.html"><b>pcrestack</b></a>
+documentation.) An alternative approach to recursion that uses memory from the
+heap to remember data, instead of using recursive function calls, has been
+implemented to work round the problem of limited stack size. If you want to
+build a version of PCRE that works this way, add
+<pre>
+  --disable-stack-for-recursion
+</pre>
+to the <b>configure</b> command. With this configuration, PCRE will use the
+<b>pcre_stack_malloc</b> and <b>pcre_stack_free</b> variables to call memory
+management functions. By default these point to <b>malloc()</b> and
+<b>free()</b>, but you can replace the pointers so that your own functions are
+used instead.
+</P>
+<P>
+Separate functions are provided rather than using <b>pcre_malloc</b> and
+<b>pcre_free</b> because the usage is very predictable: the block sizes
+requested are always the same, and the blocks are always freed in reverse
+order. A calling program might be able to implement optimized functions that
+perform better than <b>malloc()</b> and <b>free()</b>. PCRE runs noticeably more
+slowly when built in this way. This option affects only the <b>pcre_exec()</b>
+function; it is not relevant for <b>pcre_dfa_exec()</b>.
+</P>
+<br><a name="SEC14" href="#TOC1">LIMITING PCRE RESOURCE USAGE</a><br>
+<P>
+Internally, PCRE has a function called <b>match()</b>, which it calls repeatedly
+(sometimes recursively) when matching a pattern with the <b>pcre_exec()</b>
+function. By controlling the maximum number of times this function may be
+called during a single matching operation, a limit can be placed on the
+resources used by a single call to <b>pcre_exec()</b>. The limit can be changed
+at run time, as described in the
+<a href="pcreapi.html"><b>pcreapi</b></a>
+documentation. The default is 10 million, but this can be changed by adding a
+setting such as
+<pre>
+  --with-match-limit=500000
+</pre>
+to the <b>configure</b> command. This setting has no effect on the
+<b>pcre_dfa_exec()</b> matching function.
+</P>
+<P>
+In some environments it is desirable to limit the depth of recursive calls of
+<b>match()</b> more strictly than the total number of calls, in order to
+restrict the maximum amount of stack (or heap, if --disable-stack-for-recursion
+is specified) that is used. A second limit controls this; it defaults to the
+value that is set for --with-match-limit, which imposes no additional
+constraints. However, you can set a lower limit by adding, for example,
+<pre>
+  --with-match-limit-recursion=10000
+</pre>
+to the <b>configure</b> command. This value can also be overridden at run time.
+</P>
+<br><a name="SEC15" href="#TOC1">CREATING CHARACTER TABLES AT BUILD TIME</a><br>
+<P>
+PCRE uses fixed tables for processing characters whose code values are less
+than 256. By default, PCRE is built with a set of tables that are distributed
+in the file <i>pcre_chartables.c.dist</i>. These tables are for ASCII codes
+only. If you add
+<pre>
+  --enable-rebuild-chartables
+</pre>
+to the <b>configure</b> command, the distributed tables are no longer used.
+Instead, a program called <b>dftables</b> is compiled and run. This outputs the
+source for new set of tables, created in the default locale of your C run-time
+system. (This method of replacing the tables does not work if you are cross
+compiling, because <b>dftables</b> is run on the local host. If you need to
+create alternative tables when cross compiling, you will have to do so "by
+hand".)
+</P>
+<br><a name="SEC16" href="#TOC1">USING EBCDIC CODE</a><br>
+<P>
+PCRE assumes by default that it will run in an environment where the character
+code is ASCII (or Unicode, which is a superset of ASCII). This is the case for
+most computer operating systems. PCRE can, however, be compiled to run in an
+EBCDIC environment by adding
+<pre>
+  --enable-ebcdic
+</pre>
+to the <b>configure</b> command. This setting implies
+--enable-rebuild-chartables. You should only use it if you know that you are in
+an EBCDIC environment (for example, an IBM mainframe operating system). The
+--enable-ebcdic option is incompatible with --enable-utf.
+</P>
+<P>
+The EBCDIC character that corresponds to an ASCII LF is assumed to have the
+value 0x15 by default. However, in some EBCDIC environments, 0x25 is used. In
+such an environment you should use
+<pre>
+  --enable-ebcdic-nl25
+</pre>
+as well as, or instead of, --enable-ebcdic. The EBCDIC character for CR has the
+same value as in ASCII, namely, 0x0d. Whichever of 0x15 and 0x25 is <i>not</i>
+chosen as LF is made to correspond to the Unicode NEL character (which, in
+Unicode, is 0x85).
+</P>
+<P>
+The options that select newline behaviour, such as --enable-newline-is-cr,
+and equivalent run-time options, refer to these character values in an EBCDIC
+environment.
+</P>
+<br><a name="SEC17" href="#TOC1">PCREGREP OPTIONS FOR COMPRESSED FILE SUPPORT</a><br>
+<P>
+By default, <b>pcregrep</b> reads all files as plain text. You can build it so
+that it recognizes files whose names end in <b>.gz</b> or <b>.bz2</b>, and reads
+them with <b>libz</b> or <b>libbz2</b>, respectively, by adding one or both of
+<pre>
+  --enable-pcregrep-libz
+  --enable-pcregrep-libbz2
+</pre>
+to the <b>configure</b> command. These options naturally require that the
+relevant libraries are installed on your system. Configuration will fail if
+they are not.
+</P>
+<br><a name="SEC18" href="#TOC1">PCREGREP BUFFER SIZE</a><br>
+<P>
+<b>pcregrep</b> uses an internal buffer to hold a "window" on the file it is
+scanning, in order to be able to output "before" and "after" lines when it
+finds a match. The size of the buffer is controlled by a parameter whose
+default value is 20K. The buffer itself is three times this size, but because
+of the way it is used for holding "before" lines, the longest line that is
+guaranteed to be processable is the parameter size. You can change the default
+parameter value by adding, for example,
+<pre>
+  --with-pcregrep-bufsize=50K
+</pre>
+to the <b>configure</b> command. The caller of \fPpcregrep\fP can, however,
+override this value by specifying a run-time option.
+</P>
+<br><a name="SEC19" href="#TOC1">PCRETEST OPTION FOR LIBREADLINE SUPPORT</a><br>
+<P>
+If you add
+<pre>
+  --enable-pcretest-libreadline
+</pre>
+to the <b>configure</b> command, <b>pcretest</b> is linked with the
+<b>libreadline</b> library, and when its input is from a terminal, it reads it
+using the <b>readline()</b> function. This provides line-editing and history
+facilities. Note that <b>libreadline</b> is GPL-licensed, so if you distribute a
+binary of <b>pcretest</b> linked in this way, there may be licensing issues.
+</P>
+<P>
+Setting this option causes the <b>-lreadline</b> option to be added to the
+<b>pcretest</b> build. In many operating environments with a sytem-installed
+<b>libreadline</b> this is sufficient. However, in some environments (e.g.
+if an unmodified distribution version of readline is in use), some extra
+configuration may be necessary. The INSTALL file for <b>libreadline</b> says
+this:
+<pre>
+  "Readline uses the termcap functions, but does not link with the
+  termcap or curses library itself, allowing applications which link
+  with readline the to choose an appropriate library."
+</pre>
+If your environment has not been set up so that an appropriate library is
+automatically included, you may need to add something like
+<pre>
+  LIBS="-ncurses"
+</pre>
+immediately before the <b>configure</b> command.
+</P>
+<br><a name="SEC20" href="#TOC1">DEBUGGING WITH VALGRIND SUPPORT</a><br>
+<P>
+By adding the
+<pre>
+  --enable-valgrind
+</pre>
+option to to the <b>configure</b> command, PCRE will use valgrind annotations
+to mark certain memory regions as unaddressable. This allows it to detect
+invalid memory accesses, and is mostly useful for debugging PCRE itself.
+</P>
+<br><a name="SEC21" href="#TOC1">CODE COVERAGE REPORTING</a><br>
+<P>
+If your C compiler is gcc, you can build a version of PCRE that can generate a
+code coverage report for its test suite. To enable this, you must install
+<b>lcov</b> version 1.6 or above. Then specify
+<pre>
+  --enable-coverage
+</pre>
+to the <b>configure</b> command and build PCRE in the usual way.
+</P>
+<P>
+Note that using <b>ccache</b> (a caching C compiler) is incompatible with code
+coverage reporting. If you have configured <b>ccache</b> to run automatically
+on your system, you must set the environment variable
+<pre>
+  CCACHE_DISABLE=1
+</pre>
+before running <b>make</b> to build PCRE, so that <b>ccache</b> is not used.
+</P>
+<P>
+When --enable-coverage is used, the following addition targets are added to the
+<i>Makefile</i>:
+<pre>
+  make coverage
+</pre>
+This creates a fresh coverage report for the PCRE test suite. It is equivalent
+to running "make coverage-reset", "make coverage-baseline", "make check", and
+then "make coverage-report".
+<pre>
+  make coverage-reset
+</pre>
+This zeroes the coverage counters, but does nothing else.
+<pre>
+  make coverage-baseline
+</pre>
+This captures baseline coverage information.
+<pre>
+  make coverage-report
+</pre>
+This creates the coverage report.
+<pre>
+  make coverage-clean-report
+</pre>
+This removes the generated coverage report without cleaning the coverage data
+itself.
+<pre>
+  make coverage-clean-data
+</pre>
+This removes the captured coverage data without removing the coverage files
+created at compile time (*.gcno).
+<pre>
+  make coverage-clean
+</pre>
+This cleans all coverage data including the generated coverage report. For more
+information about code coverage, see the <b>gcov</b> and <b>lcov</b>
+documentation.
+</P>
+<br><a name="SEC22" href="#TOC1">SEE ALSO</a><br>
+<P>
+<b>pcreapi</b>(3), <b>pcre16</b>, <b>pcre32</b>, <b>pcre_config</b>(3).
+</P>
+<br><a name="SEC23" href="#TOC1">AUTHOR</a><br>
+<P>
+Philip Hazel
+<br>
+University Computing Service
+<br>
+Cambridge CB2 3QH, England.
+<br>
+</P>
+<br><a name="SEC24" href="#TOC1">REVISION</a><br>
+<P>
+Last updated: 12 May 2013
+<br>
+Copyright &copy; 1997-2013 University of Cambridge.
+<br>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcrecallout.html b/libs/Pcre16/docs/doc/html/pcrecallout.html
new file mode 100644
index 0000000000..53a937f52d
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcrecallout.html
@@ -0,0 +1,286 @@
+<html>
+<head>
+<title>pcrecallout specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcrecallout man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<ul>
+<li><a name="TOC1" href="#SEC1">SYNOPSIS</a>
+<li><a name="TOC2" href="#SEC2">DESCRIPTION</a>
+<li><a name="TOC3" href="#SEC3">MISSING CALLOUTS</a>
+<li><a name="TOC4" href="#SEC4">THE CALLOUT INTERFACE</a>
+<li><a name="TOC5" href="#SEC5">RETURN VALUES</a>
+<li><a name="TOC6" href="#SEC6">AUTHOR</a>
+<li><a name="TOC7" href="#SEC7">REVISION</a>
+</ul>
+<br><a name="SEC1" href="#TOC1">SYNOPSIS</a><br>
+<P>
+<b>#include &#60;pcre.h&#62;</b>
+</P>
+<P>
+<b>int (*pcre_callout)(pcre_callout_block *);</b>
+</P>
+<P>
+<b>int (*pcre16_callout)(pcre16_callout_block *);</b>
+</P>
+<P>
+<b>int (*pcre32_callout)(pcre32_callout_block *);</b>
+</P>
+<br><a name="SEC2" href="#TOC1">DESCRIPTION</a><br>
+<P>
+PCRE provides a feature called "callout", which is a means of temporarily
+passing control to the caller of PCRE in the middle of pattern matching. The
+caller of PCRE provides an external function by putting its entry point in the
+global variable <i>pcre_callout</i> (<i>pcre16_callout</i> for the 16-bit
+library, <i>pcre32_callout</i> for the 32-bit library). By default, this
+variable contains NULL, which disables all calling out.
+</P>
+<P>
+Within a regular expression, (?C) indicates the points at which the external
+function is to be called. Different callout points can be identified by putting
+a number less than 256 after the letter C. The default value is zero.
+For example, this pattern has two callout points:
+<pre>
+  (?C1)abc(?C2)def
+</pre>
+If the PCRE_AUTO_CALLOUT option bit is set when a pattern is compiled, PCRE
+automatically inserts callouts, all with number 255, before each item in the
+pattern. For example, if PCRE_AUTO_CALLOUT is used with the pattern
+<pre>
+  A(\d{2}|--)
+</pre>
+it is processed as if it were
+<br>
+<br>
+(?C255)A(?C255)((?C255)\d{2}(?C255)|(?C255)-(?C255)-(?C255))(?C255)
+<br>
+<br>
+Notice that there is a callout before and after each parenthesis and
+alternation bar. If the pattern contains a conditional group whose condition is
+an assertion, an automatic callout is inserted immediately before the
+condition. Such a callout may also be inserted explicitly, for example:
+<pre>
+  (?(?C9)(?=a)ab|de)
+</pre>
+This applies only to assertion conditions (because they are themselves
+independent groups).
+</P>
+<P>
+Automatic callouts can be used for tracking the progress of pattern matching.
+The
+<a href="pcretest.html"><b>pcretest</b></a>
+program has a pattern qualifier (/C) that sets automatic callouts; when it is
+used, the output indicates how the pattern is being matched. This is useful
+information when you are trying to optimize the performance of a particular
+pattern.
+</P>
+<br><a name="SEC3" href="#TOC1">MISSING CALLOUTS</a><br>
+<P>
+You should be aware that, because of optimizations in the way PCRE compiles and
+matches patterns, callouts sometimes do not happen exactly as you might expect.
+</P>
+<P>
+At compile time, PCRE "auto-possessifies" repeated items when it knows that
+what follows cannot be part of the repeat. For example, a+[bc] is compiled as
+if it were a++[bc]. The <b>pcretest</b> output when this pattern is anchored and
+then applied with automatic callouts to the string "aaaa" is:
+<pre>
+  ---&#62;aaaa
+   +0 ^        ^
+   +1 ^        a+
+   +3 ^   ^    [bc]
+  No match
+</pre>
+This indicates that when matching [bc] fails, there is no backtracking into a+
+and therefore the callouts that would be taken for the backtracks do not occur.
+You can disable the auto-possessify feature by passing PCRE_NO_AUTO_POSSESS
+to <b>pcre_compile()</b>, or starting the pattern with (*NO_AUTO_POSSESS). If
+this is done in <b>pcretest</b> (using the /O qualifier), the output changes to
+this:
+<pre>
+  ---&#62;aaaa
+   +0 ^        ^
+   +1 ^        a+
+   +3 ^   ^    [bc]
+   +3 ^  ^     [bc]
+   +3 ^ ^      [bc]
+   +3 ^^       [bc]
+  No match
+</pre>
+This time, when matching [bc] fails, the matcher backtracks into a+ and tries
+again, repeatedly, until a+ itself fails.
+</P>
+<P>
+Other optimizations that provide fast "no match" results also affect callouts.
+For example, if the pattern is
+<pre>
+  ab(?C4)cd
+</pre>
+PCRE knows that any matching string must contain the letter "d". If the subject
+string is "abyz", the lack of "d" means that matching doesn't ever start, and
+the callout is never reached. However, with "abyd", though the result is still
+no match, the callout is obeyed.
+</P>
+<P>
+If the pattern is studied, PCRE knows the minimum length of a matching string,
+and will immediately give a "no match" return without actually running a match
+if the subject is not long enough, or, for unanchored patterns, if it has
+been scanned far enough.
+</P>
+<P>
+You can disable these optimizations by passing the PCRE_NO_START_OPTIMIZE
+option to the matching function, or by starting the pattern with
+(*NO_START_OPT). This slows down the matching process, but does ensure that
+callouts such as the example above are obeyed.
+</P>
+<br><a name="SEC4" href="#TOC1">THE CALLOUT INTERFACE</a><br>
+<P>
+During matching, when PCRE reaches a callout point, the external function
+defined by <i>pcre_callout</i> or <i>pcre[16|32]_callout</i> is called (if it is
+set). This applies to both normal and DFA matching. The only argument to the
+callout function is a pointer to a <b>pcre_callout</b> or
+<b>pcre[16|32]_callout</b> block. These structures contains the following
+fields:
+<pre>
+  int           <i>version</i>;
+  int           <i>callout_number</i>;
+  int          *<i>offset_vector</i>;
+  const char   *<i>subject</i>;           (8-bit version)
+  PCRE_SPTR16   <i>subject</i>;           (16-bit version)
+  PCRE_SPTR32   <i>subject</i>;           (32-bit version)
+  int           <i>subject_length</i>;
+  int           <i>start_match</i>;
+  int           <i>current_position</i>;
+  int           <i>capture_top</i>;
+  int           <i>capture_last</i>;
+  void         *<i>callout_data</i>;
+  int           <i>pattern_position</i>;
+  int           <i>next_item_length</i>;
+  const unsigned char *<i>mark</i>;       (8-bit version)
+  const PCRE_UCHAR16  *<i>mark</i>;       (16-bit version)
+  const PCRE_UCHAR32  *<i>mark</i>;       (32-bit version)
+</pre>
+The <i>version</i> field is an integer containing the version number of the
+block format. The initial version was 0; the current version is 2. The version
+number will change again in future if additional fields are added, but the
+intention is never to remove any of the existing fields.
+</P>
+<P>
+The <i>callout_number</i> field contains the number of the callout, as compiled
+into the pattern (that is, the number after ?C for manual callouts, and 255 for
+automatically generated callouts).
+</P>
+<P>
+The <i>offset_vector</i> field is a pointer to the vector of offsets that was
+passed by the caller to the matching function. When <b>pcre_exec()</b> or
+<b>pcre[16|32]_exec()</b> is used, the contents can be inspected, in order to
+extract substrings that have been matched so far, in the same way as for
+extracting substrings after a match has completed. For the DFA matching
+functions, this field is not useful.
+</P>
+<P>
+The <i>subject</i> and <i>subject_length</i> fields contain copies of the values
+that were passed to the matching function.
+</P>
+<P>
+The <i>start_match</i> field normally contains the offset within the subject at
+which the current match attempt started. However, if the escape sequence \K
+has been encountered, this value is changed to reflect the modified starting
+point. If the pattern is not anchored, the callout function may be called
+several times from the same point in the pattern for different starting points
+in the subject.
+</P>
+<P>
+The <i>current_position</i> field contains the offset within the subject of the
+current match pointer.
+</P>
+<P>
+When the <b>pcre_exec()</b> or <b>pcre[16|32]_exec()</b> is used, the
+<i>capture_top</i> field contains one more than the number of the highest
+numbered captured substring so far. If no substrings have been captured, the
+value of <i>capture_top</i> is one. This is always the case when the DFA
+functions are used, because they do not support captured substrings.
+</P>
+<P>
+The <i>capture_last</i> field contains the number of the most recently captured
+substring. However, when a recursion exits, the value reverts to what it was
+outside the recursion, as do the values of all captured substrings. If no
+substrings have been captured, the value of <i>capture_last</i> is -1. This is
+always the case for the DFA matching functions.
+</P>
+<P>
+The <i>callout_data</i> field contains a value that is passed to a matching
+function specifically so that it can be passed back in callouts. It is passed
+in the <i>callout_data</i> field of a <b>pcre_extra</b> or <b>pcre[16|32]_extra</b>
+data structure. If no such data was passed, the value of <i>callout_data</i> in
+a callout block is NULL. There is a description of the <b>pcre_extra</b>
+structure in the
+<a href="pcreapi.html"><b>pcreapi</b></a>
+documentation.
+</P>
+<P>
+The <i>pattern_position</i> field is present from version 1 of the callout
+structure. It contains the offset to the next item to be matched in the pattern
+string.
+</P>
+<P>
+The <i>next_item_length</i> field is present from version 1 of the callout
+structure. It contains the length of the next item to be matched in the pattern
+string. When the callout immediately precedes an alternation bar, a closing
+parenthesis, or the end of the pattern, the length is zero. When the callout
+precedes an opening parenthesis, the length is that of the entire subpattern.
+</P>
+<P>
+The <i>pattern_position</i> and <i>next_item_length</i> fields are intended to
+help in distinguishing between different automatic callouts, which all have the
+same callout number. However, they are set for all callouts.
+</P>
+<P>
+The <i>mark</i> field is present from version 2 of the callout structure. In
+callouts from <b>pcre_exec()</b> or <b>pcre[16|32]_exec()</b> it contains a
+pointer to the zero-terminated name of the most recently passed (*MARK),
+(*PRUNE), or (*THEN) item in the match, or NULL if no such items have been
+passed. Instances of (*PRUNE) or (*THEN) without a name do not obliterate a
+previous (*MARK). In callouts from the DFA matching functions this field always
+contains NULL.
+</P>
+<br><a name="SEC5" href="#TOC1">RETURN VALUES</a><br>
+<P>
+The external callout function returns an integer to PCRE. If the value is zero,
+matching proceeds as normal. If the value is greater than zero, matching fails
+at the current point, but the testing of other matching possibilities goes
+ahead, just as if a lookahead assertion had failed. If the value is less than
+zero, the match is abandoned, the matching function returns the negative value.
+</P>
+<P>
+Negative values should normally be chosen from the set of PCRE_ERROR_xxx
+values. In particular, PCRE_ERROR_NOMATCH forces a standard "no match" failure.
+The error number PCRE_ERROR_CALLOUT is reserved for use by callout functions;
+it will never be used by PCRE itself.
+</P>
+<br><a name="SEC6" href="#TOC1">AUTHOR</a><br>
+<P>
+Philip Hazel
+<br>
+University Computing Service
+<br>
+Cambridge CB2 3QH, England.
+<br>
+</P>
+<br><a name="SEC7" href="#TOC1">REVISION</a><br>
+<P>
+Last updated: 12 November 2013
+<br>
+Copyright &copy; 1997-2013 University of Cambridge.
+<br>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcrecompat.html b/libs/Pcre16/docs/doc/html/pcrecompat.html
new file mode 100644
index 0000000000..3e6226692e
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcrecompat.html
@@ -0,0 +1,235 @@
+<html>
+<head>
+<title>pcrecompat specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcrecompat man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<br><b>
+DIFFERENCES BETWEEN PCRE AND PERL
+</b><br>
+<P>
+This document describes the differences in the ways that PCRE and Perl handle
+regular expressions. The differences described here are with respect to Perl
+versions 5.10 and above.
+</P>
+<P>
+1. PCRE has only a subset of Perl's Unicode support. Details of what it does
+have are given in the
+<a href="pcreunicode.html"><b>pcreunicode</b></a>
+page.
+</P>
+<P>
+2. PCRE allows repeat quantifiers only on parenthesized assertions, but they do
+not mean what you might think. For example, (?!a){3} does not assert that the
+next three characters are not "a". It just asserts that the next character is
+not "a" three times (in principle: PCRE optimizes this to run the assertion
+just once). Perl allows repeat quantifiers on other assertions such as \b, but
+these do not seem to have any use.
+</P>
+<P>
+3. Capturing subpatterns that occur inside negative lookahead assertions are
+counted, but their entries in the offsets vector are never set. Perl sometimes
+(but not always) sets its numerical variables from inside negative assertions.
+</P>
+<P>
+4. Though binary zero characters are supported in the subject string, they are
+not allowed in a pattern string because it is passed as a normal C string,
+terminated by zero. The escape sequence \0 can be used in the pattern to
+represent a binary zero.
+</P>
+<P>
+5. The following Perl escape sequences are not supported: \l, \u, \L,
+\U, and \N when followed by a character name or Unicode value. (\N on its
+own, matching a non-newline character, is supported.) In fact these are
+implemented by Perl's general string-handling and are not part of its pattern
+matching engine. If any of these are encountered by PCRE, an error is
+generated by default. However, if the PCRE_JAVASCRIPT_COMPAT option is set,
+\U and \u are interpreted as JavaScript interprets them.
+</P>
+<P>
+6. The Perl escape sequences \p, \P, and \X are supported only if PCRE is
+built with Unicode character property support. The properties that can be
+tested with \p and \P are limited to the general category properties such as
+Lu and Nd, script names such as Greek or Han, and the derived properties Any
+and L&. PCRE does support the Cs (surrogate) property, which Perl does not; the
+Perl documentation says "Because Perl hides the need for the user to understand
+the internal representation of Unicode characters, there is no need to
+implement the somewhat messy concept of surrogates."
+</P>
+<P>
+7. PCRE does support the \Q...\E escape for quoting substrings. Characters in
+between are treated as literals. This is slightly different from Perl in that $
+and @ are also handled as literals inside the quotes. In Perl, they cause
+variable interpolation (but of course PCRE does not have variables). Note the
+following examples:
+<pre>
+    Pattern            PCRE matches      Perl matches
+
+    \Qabc$xyz\E        abc$xyz           abc followed by the contents of $xyz
+    \Qabc\$xyz\E       abc\$xyz          abc\$xyz
+    \Qabc\E\$\Qxyz\E   abc$xyz           abc$xyz
+</pre>
+The \Q...\E sequence is recognized both inside and outside character classes.
+</P>
+<P>
+8. Fairly obviously, PCRE does not support the (?{code}) and (??{code})
+constructions. However, there is support for recursive patterns. This is not
+available in Perl 5.8, but it is in Perl 5.10. Also, the PCRE "callout"
+feature allows an external function to be called during pattern matching. See
+the
+<a href="pcrecallout.html"><b>pcrecallout</b></a>
+documentation for details.
+</P>
+<P>
+9. Subpatterns that are called as subroutines (whether or not recursively) are
+always treated as atomic groups in PCRE. This is like Python, but unlike Perl.
+Captured values that are set outside a subroutine call can be reference from
+inside in PCRE, but not in Perl. There is a discussion that explains these
+differences in more detail in the
+<a href="pcrepattern.html#recursiondifference">section on recursion differences from Perl</a>
+in the
+<a href="pcrepattern.html"><b>pcrepattern</b></a>
+page.
+</P>
+<P>
+10. If any of the backtracking control verbs are used in a subpattern that is
+called as a subroutine (whether or not recursively), their effect is confined
+to that subpattern; it does not extend to the surrounding pattern. This is not
+always the case in Perl. In particular, if (*THEN) is present in a group that
+is called as a subroutine, its action is limited to that group, even if the
+group does not contain any | characters. Note that such subpatterns are
+processed as anchored at the point where they are tested.
+</P>
+<P>
+11. If a pattern contains more than one backtracking control verb, the first
+one that is backtracked onto acts. For example, in the pattern
+A(*COMMIT)B(*PRUNE)C a failure in B triggers (*COMMIT), but a failure in C
+triggers (*PRUNE). Perl's behaviour is more complex; in many cases it is the
+same as PCRE, but there are examples where it differs.
+</P>
+<P>
+12. Most backtracking verbs in assertions have their normal actions. They are
+not confined to the assertion.
+</P>
+<P>
+13. There are some differences that are concerned with the settings of captured
+strings when part of a pattern is repeated. For example, matching "aba" against
+the pattern /^(a(b)?)+$/ in Perl leaves $2 unset, but in PCRE it is set to "b".
+</P>
+<P>
+14. PCRE's handling of duplicate subpattern numbers and duplicate subpattern
+names is not as general as Perl's. This is a consequence of the fact the PCRE
+works internally just with numbers, using an external table to translate
+between numbers and names. In particular, a pattern such as (?|(?&#60;a&#62;A)|(?&#60;b)B),
+where the two capturing parentheses have the same number but different names,
+is not supported, and causes an error at compile time. If it were allowed, it
+would not be possible to distinguish which parentheses matched, because both
+names map to capturing subpattern number 1. To avoid this confusing situation,
+an error is given at compile time.
+</P>
+<P>
+15. Perl recognizes comments in some places that PCRE does not, for example,
+between the ( and ? at the start of a subpattern. If the /x modifier is set,
+Perl allows white space between ( and ? (though current Perls warn that this is
+deprecated) but PCRE never does, even if the PCRE_EXTENDED option is set.
+</P>
+<P>
+16. Perl, when in warning mode, gives warnings for character classes such as
+[A-\d] or [a-[:digit:]]. It then treats the hyphens as literals. PCRE has no
+warning features, so it gives an error in these cases because they are almost
+certainly user mistakes.
+</P>
+<P>
+17. In PCRE, the upper/lower case character properties Lu and Ll are not
+affected when case-independent matching is specified. For example, \p{Lu}
+always matches an upper case letter. I think Perl has changed in this respect;
+in the release at the time of writing (5.16), \p{Lu} and \p{Ll} match all
+letters, regardless of case, when case independence is specified.
+</P>
+<P>
+18. PCRE provides some extensions to the Perl regular expression facilities.
+Perl 5.10 includes new features that are not in earlier versions of Perl, some
+of which (such as named parentheses) have been in PCRE for some time. This list
+is with respect to Perl 5.10:
+<br>
+<br>
+(a) Although lookbehind assertions in PCRE must match fixed length strings,
+each alternative branch of a lookbehind assertion can match a different length
+of string. Perl requires them all to have the same length.
+<br>
+<br>
+(b) If PCRE_DOLLAR_ENDONLY is set and PCRE_MULTILINE is not set, the $
+meta-character matches only at the very end of the string.
+<br>
+<br>
+(c) If PCRE_EXTRA is set, a backslash followed by a letter with no special
+meaning is faulted. Otherwise, like Perl, the backslash is quietly ignored.
+(Perl can be made to issue a warning.)
+<br>
+<br>
+(d) If PCRE_UNGREEDY is set, the greediness of the repetition quantifiers is
+inverted, that is, by default they are not greedy, but if followed by a
+question mark they are.
+<br>
+<br>
+(e) PCRE_ANCHORED can be used at matching time to force a pattern to be tried
+only at the first matching position in the subject string.
+<br>
+<br>
+(f) The PCRE_NOTBOL, PCRE_NOTEOL, PCRE_NOTEMPTY, PCRE_NOTEMPTY_ATSTART, and
+PCRE_NO_AUTO_CAPTURE options for <b>pcre_exec()</b> have no Perl equivalents.
+<br>
+<br>
+(g) The \R escape sequence can be restricted to match only CR, LF, or CRLF
+by the PCRE_BSR_ANYCRLF option.
+<br>
+<br>
+(h) The callout facility is PCRE-specific.
+<br>
+<br>
+(i) The partial matching facility is PCRE-specific.
+<br>
+<br>
+(j) Patterns compiled by PCRE can be saved and re-used at a later time, even on
+different hosts that have the other endianness. However, this does not apply to
+optimized data created by the just-in-time compiler.
+<br>
+<br>
+(k) The alternative matching functions (<b>pcre_dfa_exec()</b>,
+<b>pcre16_dfa_exec()</b> and <b>pcre32_dfa_exec()</b>,) match in a different way
+and are not Perl-compatible.
+<br>
+<br>
+(l) PCRE recognizes some special sequences such as (*CR) at the start of
+a pattern that set overall options that cannot be changed within the pattern.
+</P>
+<br><b>
+AUTHOR
+</b><br>
+<P>
+Philip Hazel
+<br>
+University Computing Service
+<br>
+Cambridge CB2 3QH, England.
+<br>
+</P>
+<br><b>
+REVISION
+</b><br>
+<P>
+Last updated: 10 November 2013
+<br>
+Copyright &copy; 1997-2013 University of Cambridge.
+<br>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcrecpp.html b/libs/Pcre16/docs/doc/html/pcrecpp.html
new file mode 100644
index 0000000000..b7eac3a3d7
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcrecpp.html
@@ -0,0 +1,368 @@
+<html>
+<head>
+<title>pcrecpp specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcrecpp man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<ul>
+<li><a name="TOC1" href="#SEC1">SYNOPSIS OF C++ WRAPPER</a>
+<li><a name="TOC2" href="#SEC2">DESCRIPTION</a>
+<li><a name="TOC3" href="#SEC3">MATCHING INTERFACE</a>
+<li><a name="TOC4" href="#SEC4">QUOTING METACHARACTERS</a>
+<li><a name="TOC5" href="#SEC5">PARTIAL MATCHES</a>
+<li><a name="TOC6" href="#SEC6">UTF-8 AND THE MATCHING INTERFACE</a>
+<li><a name="TOC7" href="#SEC7">PASSING MODIFIERS TO THE REGULAR EXPRESSION ENGINE</a>
+<li><a name="TOC8" href="#SEC8">SCANNING TEXT INCREMENTALLY</a>
+<li><a name="TOC9" href="#SEC9">PARSING HEX/OCTAL/C-RADIX NUMBERS</a>
+<li><a name="TOC10" href="#SEC10">REPLACING PARTS OF STRINGS</a>
+<li><a name="TOC11" href="#SEC11">AUTHOR</a>
+<li><a name="TOC12" href="#SEC12">REVISION</a>
+</ul>
+<br><a name="SEC1" href="#TOC1">SYNOPSIS OF C++ WRAPPER</a><br>
+<P>
+<b>#include &#60;pcrecpp.h&#62;</b>
+</P>
+<br><a name="SEC2" href="#TOC1">DESCRIPTION</a><br>
+<P>
+The C++ wrapper for PCRE was provided by Google Inc. Some additional
+functionality was added by Giuseppe Maxia. This brief man page was constructed
+from the notes in the <i>pcrecpp.h</i> file, which should be consulted for
+further details. Note that the C++ wrapper supports only the original 8-bit
+PCRE library. There is no 16-bit or 32-bit support at present.
+</P>
+<br><a name="SEC3" href="#TOC1">MATCHING INTERFACE</a><br>
+<P>
+The "FullMatch" operation checks that supplied text matches a supplied pattern
+exactly. If pointer arguments are supplied, it copies matched sub-strings that
+match sub-patterns into them.
+<pre>
+  Example: successful match
+     pcrecpp::RE re("h.*o");
+     re.FullMatch("hello");
+
+  Example: unsuccessful match (requires full match):
+     pcrecpp::RE re("e");
+     !re.FullMatch("hello");
+
+  Example: creating a temporary RE object:
+     pcrecpp::RE("h.*o").FullMatch("hello");
+</pre>
+You can pass in a "const char*" or a "string" for "text". The examples below
+tend to use a const char*. You can, as in the different examples above, store
+the RE object explicitly in a variable or use a temporary RE object. The
+examples below use one mode or the other arbitrarily. Either could correctly be
+used for any of these examples.
+</P>
+<P>
+You must supply extra pointer arguments to extract matched subpieces.
+<pre>
+  Example: extracts "ruby" into "s" and 1234 into "i"
+     int i;
+     string s;
+     pcrecpp::RE re("(\\w+):(\\d+)");
+     re.FullMatch("ruby:1234", &s, &i);
+
+  Example: does not try to extract any extra sub-patterns
+     re.FullMatch("ruby:1234", &s);
+
+  Example: does not try to extract into NULL
+     re.FullMatch("ruby:1234", NULL, &i);
+
+  Example: integer overflow causes failure
+     !re.FullMatch("ruby:1234567891234", NULL, &i);
+
+  Example: fails because there aren't enough sub-patterns:
+     !pcrecpp::RE("\\w+:\\d+").FullMatch("ruby:1234", &s);
+
+  Example: fails because string cannot be stored in integer
+     !pcrecpp::RE("(.*)").FullMatch("ruby", &i);
+</pre>
+The provided pointer arguments can be pointers to any scalar numeric
+type, or one of:
+<pre>
+   string        (matched piece is copied to string)
+   StringPiece   (StringPiece is mutated to point to matched piece)
+   T             (where "bool T::ParseFrom(const char*, int)" exists)
+   NULL          (the corresponding matched sub-pattern is not copied)
+</pre>
+The function returns true iff all of the following conditions are satisfied:
+<pre>
+  a. "text" matches "pattern" exactly;
+
+  b. The number of matched sub-patterns is &#62;= number of supplied
+     pointers;
+
+  c. The "i"th argument has a suitable type for holding the
+     string captured as the "i"th sub-pattern. If you pass in
+     void * NULL for the "i"th argument, or a non-void * NULL
+     of the correct type, or pass fewer arguments than the
+     number of sub-patterns, "i"th captured sub-pattern is
+     ignored.
+</pre>
+CAVEAT: An optional sub-pattern that does not exist in the matched
+string is assigned the empty string. Therefore, the following will
+return false (because the empty string is not a valid number):
+<pre>
+   int number;
+   pcrecpp::RE::FullMatch("abc", "[a-z]+(\\d+)?", &number);
+</pre>
+The matching interface supports at most 16 arguments per call.
+If you need more, consider using the more general interface
+<b>pcrecpp::RE::DoMatch</b>. See <b>pcrecpp.h</b> for the signature for
+<b>DoMatch</b>.
+</P>
+<P>
+NOTE: Do not use <b>no_arg</b>, which is used internally to mark the end of a
+list of optional arguments, as a placeholder for missing arguments, as this can
+lead to segfaults.
+</P>
+<br><a name="SEC4" href="#TOC1">QUOTING METACHARACTERS</a><br>
+<P>
+You can use the "QuoteMeta" operation to insert backslashes before all
+potentially meaningful characters in a string. The returned string, used as a
+regular expression, will exactly match the original string.
+<pre>
+  Example:
+     string quoted = RE::QuoteMeta(unquoted);
+</pre>
+Note that it's legal to escape a character even if it has no special meaning in
+a regular expression -- so this function does that. (This also makes it
+identical to the perl function of the same name; see "perldoc -f quotemeta".)
+For example, "1.5-2.0?" becomes "1\.5\-2\.0\?".
+</P>
+<br><a name="SEC5" href="#TOC1">PARTIAL MATCHES</a><br>
+<P>
+You can use the "PartialMatch" operation when you want the pattern
+to match any substring of the text.
+<pre>
+  Example: simple search for a string:
+     pcrecpp::RE("ell").PartialMatch("hello");
+
+  Example: find first number in a string:
+     int number;
+     pcrecpp::RE re("(\\d+)");
+     re.PartialMatch("x*100 + 20", &number);
+     assert(number == 100);
+</PRE>
+</P>
+<br><a name="SEC6" href="#TOC1">UTF-8 AND THE MATCHING INTERFACE</a><br>
+<P>
+By default, pattern and text are plain text, one byte per character. The UTF8
+flag, passed to the constructor, causes both pattern and string to be treated
+as UTF-8 text, still a byte stream but potentially multiple bytes per
+character. In practice, the text is likelier to be UTF-8 than the pattern, but
+the match returned may depend on the UTF8 flag, so always use it when matching
+UTF8 text. For example, "." will match one byte normally but with UTF8 set may
+match up to three bytes of a multi-byte character.
+<pre>
+  Example:
+     pcrecpp::RE_Options options;
+     options.set_utf8();
+     pcrecpp::RE re(utf8_pattern, options);
+     re.FullMatch(utf8_string);
+
+  Example: using the convenience function UTF8():
+     pcrecpp::RE re(utf8_pattern, pcrecpp::UTF8());
+     re.FullMatch(utf8_string);
+</pre>
+NOTE: The UTF8 flag is ignored if pcre was not configured with the
+<pre>
+      --enable-utf8 flag.
+</PRE>
+</P>
+<br><a name="SEC7" href="#TOC1">PASSING MODIFIERS TO THE REGULAR EXPRESSION ENGINE</a><br>
+<P>
+PCRE defines some modifiers to change the behavior of the regular expression
+engine. The C++ wrapper defines an auxiliary class, RE_Options, as a vehicle to
+pass such modifiers to a RE class. Currently, the following modifiers are
+supported:
+<pre>
+   modifier              description               Perl corresponding
+
+   PCRE_CASELESS         case insensitive match      /i
+   PCRE_MULTILINE        multiple lines match        /m
+   PCRE_DOTALL           dot matches newlines        /s
+   PCRE_DOLLAR_ENDONLY   $ matches only at end       N/A
+   PCRE_EXTRA            strict escape parsing       N/A
+   PCRE_EXTENDED         ignore white spaces         /x
+   PCRE_UTF8             handles UTF8 chars          built-in
+   PCRE_UNGREEDY         reverses * and *?           N/A
+   PCRE_NO_AUTO_CAPTURE  disables capturing parens   N/A (*)
+</pre>
+(*) Both Perl and PCRE allow non capturing parentheses by means of the
+"?:" modifier within the pattern itself. e.g. (?:ab|cd) does not
+capture, while (ab|cd) does.
+</P>
+<P>
+For a full account on how each modifier works, please check the
+PCRE API reference page.
+</P>
+<P>
+For each modifier, there are two member functions whose name is made
+out of the modifier in lowercase, without the "PCRE_" prefix. For
+instance, PCRE_CASELESS is handled by
+<pre>
+  bool caseless()
+</pre>
+which returns true if the modifier is set, and
+<pre>
+  RE_Options & set_caseless(bool)
+</pre>
+which sets or unsets the modifier. Moreover, PCRE_EXTRA_MATCH_LIMIT can be
+accessed through the <b>set_match_limit()</b> and <b>match_limit()</b> member
+functions. Setting <i>match_limit</i> to a non-zero value will limit the
+execution of pcre to keep it from doing bad things like blowing the stack or
+taking an eternity to return a result. A value of 5000 is good enough to stop
+stack blowup in a 2MB thread stack. Setting <i>match_limit</i> to zero disables
+match limiting. Alternatively, you can call <b>match_limit_recursion()</b>
+which uses PCRE_EXTRA_MATCH_LIMIT_RECURSION to limit how much PCRE
+recurses. <b>match_limit()</b> limits the number of matches PCRE does;
+<b>match_limit_recursion()</b> limits the depth of internal recursion, and
+therefore the amount of stack that is used.
+</P>
+<P>
+Normally, to pass one or more modifiers to a RE class, you declare
+a <i>RE_Options</i> object, set the appropriate options, and pass this
+object to a RE constructor. Example:
+<pre>
+   RE_Options opt;
+   opt.set_caseless(true);
+   if (RE("HELLO", opt).PartialMatch("hello world")) ...
+</pre>
+RE_options has two constructors. The default constructor takes no arguments and
+creates a set of flags that are off by default. The optional parameter
+<i>option_flags</i> is to facilitate transfer of legacy code from C programs.
+This lets you do
+<pre>
+   RE(pattern,
+     RE_Options(PCRE_CASELESS|PCRE_MULTILINE)).PartialMatch(str);
+</pre>
+However, new code is better off doing
+<pre>
+   RE(pattern,
+     RE_Options().set_caseless(true).set_multiline(true))
+       .PartialMatch(str);
+</pre>
+If you are going to pass one of the most used modifiers, there are some
+convenience functions that return a RE_Options class with the
+appropriate modifier already set: <b>CASELESS()</b>, <b>UTF8()</b>,
+<b>MULTILINE()</b>, <b>DOTALL</b>(), and <b>EXTENDED()</b>.
+</P>
+<P>
+If you need to set several options at once, and you don't want to go through
+the pains of declaring a RE_Options object and setting several options, there
+is a parallel method that give you such ability on the fly. You can concatenate
+several <b>set_xxxxx()</b> member functions, since each of them returns a
+reference to its class object. For example, to pass PCRE_CASELESS,
+PCRE_EXTENDED, and PCRE_MULTILINE to a RE with one statement, you may write:
+<pre>
+   RE(" ^ xyz \\s+ .* blah$",
+     RE_Options()
+       .set_caseless(true)
+       .set_extended(true)
+       .set_multiline(true)).PartialMatch(sometext);
+
+</PRE>
+</P>
+<br><a name="SEC8" href="#TOC1">SCANNING TEXT INCREMENTALLY</a><br>
+<P>
+The "Consume" operation may be useful if you want to repeatedly
+match regular expressions at the front of a string and skip over
+them as they match. This requires use of the "StringPiece" type,
+which represents a sub-range of a real string. Like RE, StringPiece
+is defined in the pcrecpp namespace.
+<pre>
+  Example: read lines of the form "var = value" from a string.
+     string contents = ...;                 // Fill string somehow
+     pcrecpp::StringPiece input(contents);  // Wrap in a StringPiece
+
+     string var;
+     int value;
+     pcrecpp::RE re("(\\w+) = (\\d+)\n");
+     while (re.Consume(&input, &var, &value)) {
+       ...;
+     }
+</pre>
+Each successful call to "Consume" will set "var/value", and also
+advance "input" so it points past the matched text.
+</P>
+<P>
+The "FindAndConsume" operation is similar to "Consume" but does not
+anchor your match at the beginning of the string. For example, you
+could extract all words from a string by repeatedly calling
+<pre>
+  pcrecpp::RE("(\\w+)").FindAndConsume(&input, &word)
+</PRE>
+</P>
+<br><a name="SEC9" href="#TOC1">PARSING HEX/OCTAL/C-RADIX NUMBERS</a><br>
+<P>
+By default, if you pass a pointer to a numeric value, the
+corresponding text is interpreted as a base-10 number. You can
+instead wrap the pointer with a call to one of the operators Hex(),
+Octal(), or CRadix() to interpret the text in another base. The
+CRadix operator interprets C-style "0" (base-8) and "0x" (base-16)
+prefixes, but defaults to base-10.
+<pre>
+  Example:
+    int a, b, c, d;
+    pcrecpp::RE re("(.*) (.*) (.*) (.*)");
+    re.FullMatch("100 40 0100 0x40",
+                 pcrecpp::Octal(&a), pcrecpp::Hex(&b),
+                 pcrecpp::CRadix(&c), pcrecpp::CRadix(&d));
+</pre>
+will leave 64 in a, b, c, and d.
+</P>
+<br><a name="SEC10" href="#TOC1">REPLACING PARTS OF STRINGS</a><br>
+<P>
+You can replace the first match of "pattern" in "str" with "rewrite".
+Within "rewrite", backslash-escaped digits (\1 to \9) can be
+used to insert text matching corresponding parenthesized group
+from the pattern. \0 in "rewrite" refers to the entire matching
+text. For example:
+<pre>
+  string s = "yabba dabba doo";
+  pcrecpp::RE("b+").Replace("d", &s);
+</pre>
+will leave "s" containing "yada dabba doo". The result is true if the pattern
+matches and a replacement occurs, false otherwise.
+</P>
+<P>
+<b>GlobalReplace</b> is like <b>Replace</b> except that it replaces all
+occurrences of the pattern in the string with the rewrite. Replacements are
+not subject to re-matching. For example:
+<pre>
+  string s = "yabba dabba doo";
+  pcrecpp::RE("b+").GlobalReplace("d", &s);
+</pre>
+will leave "s" containing "yada dada doo". It returns the number of
+replacements made.
+</P>
+<P>
+<b>Extract</b> is like <b>Replace</b>, except that if the pattern matches,
+"rewrite" is copied into "out" (an additional argument) with substitutions.
+The non-matching portions of "text" are ignored. Returns true iff a match
+occurred and the extraction happened successfully;  if no match occurs, the
+string is left unaffected.
+</P>
+<br><a name="SEC11" href="#TOC1">AUTHOR</a><br>
+<P>
+The C++ wrapper was contributed by Google Inc.
+<br>
+Copyright &copy; 2007 Google Inc.
+<br>
+</P>
+<br><a name="SEC12" href="#TOC1">REVISION</a><br>
+<P>
+Last updated: 08 January 2012
+<br>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcredemo.html b/libs/Pcre16/docs/doc/html/pcredemo.html
new file mode 100644
index 0000000000..894a930826
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcredemo.html
@@ -0,0 +1,426 @@
+<html>
+<head>
+<title>pcredemo specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcredemo man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<ul>
+</ul>
+<PRE>
+/*************************************************
+*           PCRE DEMONSTRATION PROGRAM           *
+*************************************************/
+
+/* This is a demonstration program to illustrate the most straightforward ways
+of calling the PCRE regular expression library from a C program. See the
+pcresample documentation for a short discussion ("man pcresample" if you have
+the PCRE man pages installed).
+
+In Unix-like environments, if PCRE is installed in your standard system
+libraries, you should be able to compile this program using this command:
+
+gcc -Wall pcredemo.c -lpcre -o pcredemo
+
+If PCRE is not installed in a standard place, it is likely to be installed with
+support for the pkg-config mechanism. If you have pkg-config, you can compile
+this program using this command:
+
+gcc -Wall pcredemo.c `pkg-config --cflags --libs libpcre` -o pcredemo
+
+If you do not have pkg-config, you may have to use this:
+
+gcc -Wall pcredemo.c -I/usr/local/include -L/usr/local/lib \
+  -R/usr/local/lib -lpcre -o pcredemo
+
+Replace "/usr/local/include" and "/usr/local/lib" with wherever the include and
+library files for PCRE are installed on your system. Only some operating
+systems (e.g. Solaris) use the -R option.
+
+Building under Windows:
+
+If you want to statically link this program against a non-dll .a file, you must
+define PCRE_STATIC before including pcre.h, otherwise the pcre_malloc() and
+pcre_free() exported functions will be declared __declspec(dllimport), with
+unwanted results. So in this environment, uncomment the following line. */
+
+/* #define PCRE_STATIC */
+
+#include &lt;stdio.h&gt;
+#include &lt;string.h&gt;
+#include &lt;pcre.h&gt;
+
+#define OVECCOUNT 30    /* should be a multiple of 3 */
+
+
+int main(int argc, char **argv)
+{
+pcre *re;
+const char *error;
+char *pattern;
+char *subject;
+unsigned char *name_table;
+unsigned int option_bits;
+int erroffset;
+int find_all;
+int crlf_is_newline;
+int namecount;
+int name_entry_size;
+int ovector[OVECCOUNT];
+int subject_length;
+int rc, i;
+int utf8;
+
+
+/**************************************************************************
+* First, sort out the command line. There is only one possible option at  *
+* the moment, "-g" to request repeated matching to find all occurrences,  *
+* like Perl's /g option. We set the variable find_all to a non-zero value *
+* if the -g option is present. Apart from that, there must be exactly two *
+* arguments.                                                              *
+**************************************************************************/
+
+find_all = 0;
+for (i = 1; i &lt; argc; i++)
+  {
+  if (strcmp(argv[i], "-g") == 0) find_all = 1;
+    else break;
+  }
+
+/* After the options, we require exactly two arguments, which are the pattern,
+and the subject string. */
+
+if (argc - i != 2)
+  {
+  printf("Two arguments required: a regex and a subject string\n");
+  return 1;
+  }
+
+pattern = argv[i];
+subject = argv[i+1];
+subject_length = (int)strlen(subject);
+
+
+/*************************************************************************
+* Now we are going to compile the regular expression pattern, and handle *
+* and errors that are detected.                                          *
+*************************************************************************/
+
+re = pcre_compile(
+  pattern,              /* the pattern */
+  0,                    /* default options */
+  &amp;error,               /* for error message */
+  &amp;erroffset,           /* for error offset */
+  NULL);                /* use default character tables */
+
+/* Compilation failed: print the error message and exit */
+
+if (re == NULL)
+  {
+  printf("PCRE compilation failed at offset %d: %s\n", erroffset, error);
+  return 1;
+  }
+
+
+/*************************************************************************
+* If the compilation succeeded, we call PCRE again, in order to do a     *
+* pattern match against the subject string. This does just ONE match. If *
+* further matching is needed, it will be done below.                     *
+*************************************************************************/
+
+rc = pcre_exec(
+  re,                   /* the compiled pattern */
+  NULL,                 /* no extra data - we didn't study the pattern */
+  subject,              /* the subject string */
+  subject_length,       /* the length of the subject */
+  0,                    /* start at offset 0 in the subject */
+  0,                    /* default options */
+  ovector,              /* output vector for substring information */
+  OVECCOUNT);           /* number of elements in the output vector */
+
+/* Matching failed: handle error cases */
+
+if (rc &lt; 0)
+  {
+  switch(rc)
+    {
+    case PCRE_ERROR_NOMATCH: printf("No match\n"); break;
+    /*
+    Handle other special cases if you like
+    */
+    default: printf("Matching error %d\n", rc); break;
+    }
+  pcre_free(re);     /* Release memory used for the compiled pattern */
+  return 1;
+  }
+
+/* Match succeded */
+
+printf("\nMatch succeeded at offset %d\n", ovector[0]);
+
+
+/*************************************************************************
+* We have found the first match within the subject string. If the output *
+* vector wasn't big enough, say so. Then output any substrings that were *
+* captured.                                                              *
+*************************************************************************/
+
+/* The output vector wasn't big enough */
+
+if (rc == 0)
+  {
+  rc = OVECCOUNT/3;
+  printf("ovector only has room for %d captured substrings\n", rc - 1);
+  }
+
+/* Show substrings stored in the output vector by number. Obviously, in a real
+application you might want to do things other than print them. */
+
+for (i = 0; i &lt; rc; i++)
+  {
+  char *substring_start = subject + ovector[2*i];
+  int substring_length = ovector[2*i+1] - ovector[2*i];
+  printf("%2d: %.*s\n", i, substring_length, substring_start);
+  }
+
+
+/**************************************************************************
+* That concludes the basic part of this demonstration program. We have    *
+* compiled a pattern, and performed a single match. The code that follows *
+* shows first how to access named substrings, and then how to code for    *
+* repeated matches on the same subject.                                   *
+**************************************************************************/
+
+/* See if there are any named substrings, and if so, show them by name. First
+we have to extract the count of named parentheses from the pattern. */
+
+(void)pcre_fullinfo(
+  re,                   /* the compiled pattern */
+  NULL,                 /* no extra data - we didn't study the pattern */
+  PCRE_INFO_NAMECOUNT,  /* number of named substrings */
+  &amp;namecount);          /* where to put the answer */
+
+if (namecount &lt;= 0) printf("No named substrings\n"); else
+  {
+  unsigned char *tabptr;
+  printf("Named substrings\n");
+
+  /* Before we can access the substrings, we must extract the table for
+  translating names to numbers, and the size of each entry in the table. */
+
+  (void)pcre_fullinfo(
+    re,                       /* the compiled pattern */
+    NULL,                     /* no extra data - we didn't study the pattern */
+    PCRE_INFO_NAMETABLE,      /* address of the table */
+    &amp;name_table);             /* where to put the answer */
+
+  (void)pcre_fullinfo(
+    re,                       /* the compiled pattern */
+    NULL,                     /* no extra data - we didn't study the pattern */
+    PCRE_INFO_NAMEENTRYSIZE,  /* size of each entry in the table */
+    &amp;name_entry_size);        /* where to put the answer */
+
+  /* Now we can scan the table and, for each entry, print the number, the name,
+  and the substring itself. */
+
+  tabptr = name_table;
+  for (i = 0; i &lt; namecount; i++)
+    {
+    int n = (tabptr[0] &lt;&lt; 8) | tabptr[1];
+    printf("(%d) %*s: %.*s\n", n, name_entry_size - 3, tabptr + 2,
+      ovector[2*n+1] - ovector[2*n], subject + ovector[2*n]);
+    tabptr += name_entry_size;
+    }
+  }
+
+
+/*************************************************************************
+* If the "-g" option was given on the command line, we want to continue  *
+* to search for additional matches in the subject string, in a similar   *
+* way to the /g option in Perl. This turns out to be trickier than you   *
+* might think because of the possibility of matching an empty string.    *
+* What happens is as follows:                                            *
+*                                                                        *
+* If the previous match was NOT for an empty string, we can just start   *
+* the next match at the end of the previous one.                         *
+*                                                                        *
+* If the previous match WAS for an empty string, we can't do that, as it *
+* would lead to an infinite loop. Instead, a special call of pcre_exec() *
+* is made with the PCRE_NOTEMPTY_ATSTART and PCRE_ANCHORED flags set.    *
+* The first of these tells PCRE that an empty string at the start of the *
+* subject is not a valid match; other possibilities must be tried. The   *
+* second flag restricts PCRE to one match attempt at the initial string  *
+* position. If this match succeeds, an alternative to the empty string   *
+* match has been found, and we can print it and proceed round the loop,  *
+* advancing by the length of whatever was found. If this match does not  *
+* succeed, we still stay in the loop, advancing by just one character.   *
+* In UTF-8 mode, which can be set by (*UTF8) in the pattern, this may be *
+* more than one byte.                                                    *
+*                                                                        *
+* However, there is a complication concerned with newlines. When the     *
+* newline convention is such that CRLF is a valid newline, we must       *
+* advance by two characters rather than one. The newline convention can  *
+* be set in the regex by (*CR), etc.; if not, we must find the default.  *
+*************************************************************************/
+
+if (!find_all)     /* Check for -g */
+  {
+  pcre_free(re);   /* Release the memory used for the compiled pattern */
+  return 0;        /* Finish unless -g was given */
+  }
+
+/* Before running the loop, check for UTF-8 and whether CRLF is a valid newline
+sequence. First, find the options with which the regex was compiled; extract
+the UTF-8 state, and mask off all but the newline options. */
+
+(void)pcre_fullinfo(re, NULL, PCRE_INFO_OPTIONS, &amp;option_bits);
+utf8 = option_bits &amp; PCRE_UTF8;
+option_bits &amp;= PCRE_NEWLINE_CR|PCRE_NEWLINE_LF|PCRE_NEWLINE_CRLF|
+               PCRE_NEWLINE_ANY|PCRE_NEWLINE_ANYCRLF;
+
+/* If no newline options were set, find the default newline convention from the
+build configuration. */
+
+if (option_bits == 0)
+  {
+  int d;
+  (void)pcre_config(PCRE_CONFIG_NEWLINE, &amp;d);
+  /* Note that these values are always the ASCII ones, even in
+  EBCDIC environments. CR = 13, NL = 10. */
+  option_bits = (d == 13)? PCRE_NEWLINE_CR :
+          (d == 10)? PCRE_NEWLINE_LF :
+          (d == (13&lt;&lt;8 | 10))? PCRE_NEWLINE_CRLF :
+          (d == -2)? PCRE_NEWLINE_ANYCRLF :
+          (d == -1)? PCRE_NEWLINE_ANY : 0;
+  }
+
+/* See if CRLF is a valid newline sequence. */
+
+crlf_is_newline =
+     option_bits == PCRE_NEWLINE_ANY ||
+     option_bits == PCRE_NEWLINE_CRLF ||
+     option_bits == PCRE_NEWLINE_ANYCRLF;
+
+/* Loop for second and subsequent matches */
+
+for (;;)
+  {
+  int options = 0;                 /* Normally no options */
+  int start_offset = ovector[1];   /* Start at end of previous match */
+
+  /* If the previous match was for an empty string, we are finished if we are
+  at the end of the subject. Otherwise, arrange to run another match at the
+  same point to see if a non-empty match can be found. */
+
+  if (ovector[0] == ovector[1])
+    {
+    if (ovector[0] == subject_length) break;
+    options = PCRE_NOTEMPTY_ATSTART | PCRE_ANCHORED;
+    }
+
+  /* Run the next matching operation */
+
+  rc = pcre_exec(
+    re,                   /* the compiled pattern */
+    NULL,                 /* no extra data - we didn't study the pattern */
+    subject,              /* the subject string */
+    subject_length,       /* the length of the subject */
+    start_offset,         /* starting offset in the subject */
+    options,              /* options */
+    ovector,              /* output vector for substring information */
+    OVECCOUNT);           /* number of elements in the output vector */
+
+  /* This time, a result of NOMATCH isn't an error. If the value in "options"
+  is zero, it just means we have found all possible matches, so the loop ends.
+  Otherwise, it means we have failed to find a non-empty-string match at a
+  point where there was a previous empty-string match. In this case, we do what
+  Perl does: advance the matching position by one character, and continue. We
+  do this by setting the "end of previous match" offset, because that is picked
+  up at the top of the loop as the point at which to start again.
+
+  There are two complications: (a) When CRLF is a valid newline sequence, and
+  the current position is just before it, advance by an extra byte. (b)
+  Otherwise we must ensure that we skip an entire UTF-8 character if we are in
+  UTF-8 mode. */
+
+  if (rc == PCRE_ERROR_NOMATCH)
+    {
+    if (options == 0) break;                    /* All matches found */
+    ovector[1] = start_offset + 1;              /* Advance one byte */
+    if (crlf_is_newline &amp;&amp;                      /* If CRLF is newline &amp; */
+        start_offset &lt; subject_length - 1 &amp;&amp;    /* we are at CRLF, */
+        subject[start_offset] == '\r' &amp;&amp;
+        subject[start_offset + 1] == '\n')
+      ovector[1] += 1;                          /* Advance by one more. */
+    else if (utf8)                              /* Otherwise, ensure we */
+      {                                         /* advance a whole UTF-8 */
+      while (ovector[1] &lt; subject_length)       /* character. */
+        {
+        if ((subject[ovector[1]] &amp; 0xc0) != 0x80) break;
+        ovector[1] += 1;
+        }
+      }
+    continue;    /* Go round the loop again */
+    }
+
+  /* Other matching errors are not recoverable. */
+
+  if (rc &lt; 0)
+    {
+    printf("Matching error %d\n", rc);
+    pcre_free(re);    /* Release memory used for the compiled pattern */
+    return 1;
+    }
+
+  /* Match succeded */
+
+  printf("\nMatch succeeded again at offset %d\n", ovector[0]);
+
+  /* The match succeeded, but the output vector wasn't big enough. */
+
+  if (rc == 0)
+    {
+    rc = OVECCOUNT/3;
+    printf("ovector only has room for %d captured substrings\n", rc - 1);
+    }
+
+  /* As before, show substrings stored in the output vector by number, and then
+  also any named substrings. */
+
+  for (i = 0; i &lt; rc; i++)
+    {
+    char *substring_start = subject + ovector[2*i];
+    int substring_length = ovector[2*i+1] - ovector[2*i];
+    printf("%2d: %.*s\n", i, substring_length, substring_start);
+    }
+
+  if (namecount &lt;= 0) printf("No named substrings\n"); else
+    {
+    unsigned char *tabptr = name_table;
+    printf("Named substrings\n");
+    for (i = 0; i &lt; namecount; i++)
+      {
+      int n = (tabptr[0] &lt;&lt; 8) | tabptr[1];
+      printf("(%d) %*s: %.*s\n", n, name_entry_size - 3, tabptr + 2,
+        ovector[2*n+1] - ovector[2*n], subject + ovector[2*n]);
+      tabptr += name_entry_size;
+      }
+    }
+  }      /* End of loop to find second and subsequent matches */
+
+printf("\n");
+pcre_free(re);       /* Release memory used for the compiled pattern */
+return 0;
+}
+
+/* End of pcredemo.c */
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcregrep.html b/libs/Pcre16/docs/doc/html/pcregrep.html
new file mode 100644
index 0000000000..dacbb4998f
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcregrep.html
@@ -0,0 +1,759 @@
+<html>
+<head>
+<title>pcregrep specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcregrep man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<ul>
+<li><a name="TOC1" href="#SEC1">SYNOPSIS</a>
+<li><a name="TOC2" href="#SEC2">DESCRIPTION</a>
+<li><a name="TOC3" href="#SEC3">SUPPORT FOR COMPRESSED FILES</a>
+<li><a name="TOC4" href="#SEC4">BINARY FILES</a>
+<li><a name="TOC5" href="#SEC5">OPTIONS</a>
+<li><a name="TOC6" href="#SEC6">ENVIRONMENT VARIABLES</a>
+<li><a name="TOC7" href="#SEC7">NEWLINES</a>
+<li><a name="TOC8" href="#SEC8">OPTIONS COMPATIBILITY</a>
+<li><a name="TOC9" href="#SEC9">OPTIONS WITH DATA</a>
+<li><a name="TOC10" href="#SEC10">MATCHING ERRORS</a>
+<li><a name="TOC11" href="#SEC11">DIAGNOSTICS</a>
+<li><a name="TOC12" href="#SEC12">SEE ALSO</a>
+<li><a name="TOC13" href="#SEC13">AUTHOR</a>
+<li><a name="TOC14" href="#SEC14">REVISION</a>
+</ul>
+<br><a name="SEC1" href="#TOC1">SYNOPSIS</a><br>
+<P>
+<b>pcregrep [options] [long options] [pattern] [path1 path2 ...]</b>
+</P>
+<br><a name="SEC2" href="#TOC1">DESCRIPTION</a><br>
+<P>
+<b>pcregrep</b> searches files for character patterns, in the same way as other
+grep commands do, but it uses the PCRE regular expression library to support
+patterns that are compatible with the regular expressions of Perl 5. See
+<a href="pcresyntax.html"><b>pcresyntax</b>(3)</a>
+for a quick-reference summary of pattern syntax, or
+<a href="pcrepattern.html"><b>pcrepattern</b>(3)</a>
+for a full description of the syntax and semantics of the regular expressions
+that PCRE supports.
+</P>
+<P>
+Patterns, whether supplied on the command line or in a separate file, are given
+without delimiters. For example:
+<pre>
+  pcregrep Thursday /etc/motd
+</pre>
+If you attempt to use delimiters (for example, by surrounding a pattern with
+slashes, as is common in Perl scripts), they are interpreted as part of the
+pattern. Quotes can of course be used to delimit patterns on the command line
+because they are interpreted by the shell, and indeed quotes are required if a
+pattern contains white space or shell metacharacters.
+</P>
+<P>
+The first argument that follows any option settings is treated as the single
+pattern to be matched when neither <b>-e</b> nor <b>-f</b> is present.
+Conversely, when one or both of these options are used to specify patterns, all
+arguments are treated as path names. At least one of <b>-e</b>, <b>-f</b>, or an
+argument pattern must be provided.
+</P>
+<P>
+If no files are specified, <b>pcregrep</b> reads the standard input. The
+standard input can also be referenced by a name consisting of a single hyphen.
+For example:
+<pre>
+  pcregrep some-pattern /file1 - /file3
+</pre>
+By default, each line that matches a pattern is copied to the standard
+output, and if there is more than one file, the file name is output at the
+start of each line, followed by a colon. However, there are options that can
+change how <b>pcregrep</b> behaves. In particular, the <b>-M</b> option makes it
+possible to search for patterns that span line boundaries. What defines a line
+boundary is controlled by the <b>-N</b> (<b>--newline</b>) option.
+</P>
+<P>
+The amount of memory used for buffering files that are being scanned is
+controlled by a parameter that can be set by the <b>--buffer-size</b> option.
+The default value for this parameter is specified when <b>pcregrep</b> is built,
+with the default default being 20K. A block of memory three times this size is
+used (to allow for buffering "before" and "after" lines). An error occurs if a
+line overflows the buffer.
+</P>
+<P>
+Patterns can be no longer than 8K or BUFSIZ bytes, whichever is the greater.
+BUFSIZ is defined in <b>&#60;stdio.h&#62;</b>. When there is more than one pattern
+(specified by the use of <b>-e</b> and/or <b>-f</b>), each pattern is applied to
+each line in the order in which they are defined, except that all the <b>-e</b>
+patterns are tried before the <b>-f</b> patterns.
+</P>
+<P>
+By default, as soon as one pattern matches a line, no further patterns are
+considered. However, if <b>--colour</b> (or <b>--color</b>) is used to colour the
+matching substrings, or if <b>--only-matching</b>, <b>--file-offsets</b>, or
+<b>--line-offsets</b> is used to output only the part of the line that matched
+(either shown literally, or as an offset), scanning resumes immediately
+following the match, so that further matches on the same line can be found. If
+there are multiple patterns, they are all tried on the remainder of the line,
+but patterns that follow the one that matched are not tried on the earlier part
+of the line.
+</P>
+<P>
+This behaviour means that the order in which multiple patterns are specified
+can affect the output when one of the above options is used. This is no longer
+the same behaviour as GNU grep, which now manages to display earlier matches
+for later patterns (as long as there is no overlap).
+</P>
+<P>
+Patterns that can match an empty string are accepted, but empty string
+matches are never recognized. An example is the pattern "(super)?(man)?", in
+which all components are optional. This pattern finds all occurrences of both
+"super" and "man"; the output differs from matching with "super|man" when only
+the matching substrings are being shown.
+</P>
+<P>
+If the <b>LC_ALL</b> or <b>LC_CTYPE</b> environment variable is set,
+<b>pcregrep</b> uses the value to set a locale when calling the PCRE library.
+The <b>--locale</b> option can be used to override this.
+</P>
+<br><a name="SEC3" href="#TOC1">SUPPORT FOR COMPRESSED FILES</a><br>
+<P>
+It is possible to compile <b>pcregrep</b> so that it uses <b>libz</b> or
+<b>libbz2</b> to read files whose names end in <b>.gz</b> or <b>.bz2</b>,
+respectively. You can find out whether your binary has support for one or both
+of these file types by running it with the <b>--help</b> option. If the
+appropriate support is not present, files are treated as plain text. The
+standard input is always so treated.
+</P>
+<br><a name="SEC4" href="#TOC1">BINARY FILES</a><br>
+<P>
+By default, a file that contains a binary zero byte within the first 1024 bytes
+is identified as a binary file, and is processed specially. (GNU grep also
+identifies binary files in this manner.) See the <b>--binary-files</b> option
+for a means of changing the way binary files are handled.
+</P>
+<br><a name="SEC5" href="#TOC1">OPTIONS</a><br>
+<P>
+The order in which some of the options appear can affect the output. For
+example, both the <b>-h</b> and <b>-l</b> options affect the printing of file
+names. Whichever comes later in the command line will be the one that takes
+effect. Similarly, except where noted below, if an option is given twice, the
+later setting is used. Numerical values for options may be followed by K or M,
+to signify multiplication by 1024 or 1024*1024 respectively.
+</P>
+<P>
+<b>--</b>
+This terminates the list of options. It is useful if the next item on the
+command line starts with a hyphen but is not an option. This allows for the
+processing of patterns and filenames that start with hyphens.
+</P>
+<P>
+<b>-A</b> <i>number</i>, <b>--after-context=</b><i>number</i>
+Output <i>number</i> lines of context after each matching line. If filenames
+and/or line numbers are being output, a hyphen separator is used instead of a
+colon for the context lines. A line containing "--" is output between each
+group of lines, unless they are in fact contiguous in the input file. The value
+of <i>number</i> is expected to be relatively small. However, <b>pcregrep</b>
+guarantees to have up to 8K of following text available for context output.
+</P>
+<P>
+<b>-a</b>, <b>--text</b>
+Treat binary files as text. This is equivalent to
+<b>--binary-files</b>=<i>text</i>.
+</P>
+<P>
+<b>-B</b> <i>number</i>, <b>--before-context=</b><i>number</i>
+Output <i>number</i> lines of context before each matching line. If filenames
+and/or line numbers are being output, a hyphen separator is used instead of a
+colon for the context lines. A line containing "--" is output between each
+group of lines, unless they are in fact contiguous in the input file. The value
+of <i>number</i> is expected to be relatively small. However, <b>pcregrep</b>
+guarantees to have up to 8K of preceding text available for context output.
+</P>
+<P>
+<b>--binary-files=</b><i>word</i>
+Specify how binary files are to be processed. If the word is "binary" (the
+default), pattern matching is performed on binary files, but the only output is
+"Binary file &#60;name&#62; matches" when a match succeeds. If the word is "text",
+which is equivalent to the <b>-a</b> or <b>--text</b> option, binary files are
+processed in the same way as any other file. In this case, when a match
+succeeds, the output may be binary garbage, which can have nasty effects if
+sent to a terminal. If the word is "without-match", which is equivalent to the
+<b>-I</b> option, binary files are not processed at all; they are assumed not to
+be of interest.
+</P>
+<P>
+<b>--buffer-size=</b><i>number</i>
+Set the parameter that controls how much memory is used for buffering files
+that are being scanned.
+</P>
+<P>
+<b>-C</b> <i>number</i>, <b>--context=</b><i>number</i>
+Output <i>number</i> lines of context both before and after each matching line.
+This is equivalent to setting both <b>-A</b> and <b>-B</b> to the same value.
+</P>
+<P>
+<b>-c</b>, <b>--count</b>
+Do not output individual lines from the files that are being scanned; instead
+output the number of lines that would otherwise have been shown. If no lines
+are selected, the number zero is output. If several files are are being
+scanned, a count is output for each of them. However, if the
+<b>--files-with-matches</b> option is also used, only those files whose counts
+are greater than zero are listed. When <b>-c</b> is used, the <b>-A</b>,
+<b>-B</b>, and <b>-C</b> options are ignored.
+</P>
+<P>
+<b>--colour</b>, <b>--color</b>
+If this option is given without any data, it is equivalent to "--colour=auto".
+If data is required, it must be given in the same shell item, separated by an
+equals sign.
+</P>
+<P>
+<b>--colour=</b><i>value</i>, <b>--color=</b><i>value</i>
+This option specifies under what circumstances the parts of a line that matched
+a pattern should be coloured in the output. By default, the output is not
+coloured. The value (which is optional, see above) may be "never", "always", or
+"auto". In the latter case, colouring happens only if the standard output is
+connected to a terminal. More resources are used when colouring is enabled,
+because <b>pcregrep</b> has to search for all possible matches in a line, not
+just one, in order to colour them all.
+<br>
+<br>
+The colour that is used can be specified by setting the environment variable
+PCREGREP_COLOUR or PCREGREP_COLOR. The value of this variable should be a
+string of two numbers, separated by a semicolon. They are copied directly into
+the control string for setting colour on a terminal, so it is your
+responsibility to ensure that they make sense. If neither of the environment
+variables is set, the default is "1;31", which gives red.
+</P>
+<P>
+<b>-D</b> <i>action</i>, <b>--devices=</b><i>action</i>
+If an input path is not a regular file or a directory, "action" specifies how
+it is to be processed. Valid values are "read" (the default) or "skip"
+(silently skip the path).
+</P>
+<P>
+<b>-d</b> <i>action</i>, <b>--directories=</b><i>action</i>
+If an input path is a directory, "action" specifies how it is to be processed.
+Valid values are "read" (the default in non-Windows environments, for
+compatibility with GNU grep), "recurse" (equivalent to the <b>-r</b> option), or
+"skip" (silently skip the path, the default in Windows environments). In the
+"read" case, directories are read as if they were ordinary files. In some
+operating systems the effect of reading a directory like this is an immediate
+end-of-file; in others it may provoke an error.
+</P>
+<P>
+<b>-e</b> <i>pattern</i>, <b>--regex=</b><i>pattern</i>, <b>--regexp=</b><i>pattern</i>
+Specify a pattern to be matched. This option can be used multiple times in
+order to specify several patterns. It can also be used as a way of specifying a
+single pattern that starts with a hyphen. When <b>-e</b> is used, no argument
+pattern is taken from the command line; all arguments are treated as file
+names. There is no limit to the number of patterns. They are applied to each
+line in the order in which they are defined until one matches.
+<br>
+<br>
+If <b>-f</b> is used with <b>-e</b>, the command line patterns are matched first,
+followed by the patterns from the file(s), independent of the order in which
+these options are specified. Note that multiple use of <b>-e</b> is not the same
+as a single pattern with alternatives. For example, X|Y finds the first
+character in a line that is X or Y, whereas if the two patterns are given
+separately, with X first, <b>pcregrep</b> finds X if it is present, even if it
+follows Y in the line. It finds Y only if there is no X in the line. This
+matters only if you are using <b>-o</b> or <b>--colo(u)r</b> to show the part(s)
+of the line that matched.
+</P>
+<P>
+<b>--exclude</b>=<i>pattern</i>
+Files (but not directories) whose names match the pattern are skipped without
+being processed. This applies to all files, whether listed on the command line,
+obtained from <b>--file-list</b>, or by scanning a directory. The pattern is a
+PCRE regular expression, and is matched against the final component of the file
+name, not the entire path. The <b>-F</b>, <b>-w</b>, and <b>-x</b> options do not
+apply to this pattern. The option may be given any number of times in order to
+specify multiple patterns. If a file name matches both an <b>--include</b>
+and an <b>--exclude</b> pattern, it is excluded. There is no short form for this
+option.
+</P>
+<P>
+<b>--exclude-from=</b><i>filename</i>
+Treat each non-empty line of the file as the data for an <b>--exclude</b>
+option. What constitutes a newline when reading the file is the operating
+system's default. The <b>--newline</b> option has no effect on this option. This
+option may be given more than once in order to specify a number of files to
+read.
+</P>
+<P>
+<b>--exclude-dir</b>=<i>pattern</i>
+Directories whose names match the pattern are skipped without being processed,
+whatever the setting of the <b>--recursive</b> option. This applies to all
+directories, whether listed on the command line, obtained from
+<b>--file-list</b>, or by scanning a parent directory. The pattern is a PCRE
+regular expression, and is matched against the final component of the directory
+name, not the entire path. The <b>-F</b>, <b>-w</b>, and <b>-x</b> options do not
+apply to this pattern. The option may be given any number of times in order to
+specify more than one pattern. If a directory matches both <b>--include-dir</b>
+and <b>--exclude-dir</b>, it is excluded. There is no short form for this
+option.
+</P>
+<P>
+<b>-F</b>, <b>--fixed-strings</b>
+Interpret each data-matching pattern as a list of fixed strings, separated by
+newlines, instead of as a regular expression. What constitutes a newline for
+this purpose is controlled by the <b>--newline</b> option. The <b>-w</b> (match
+as a word) and <b>-x</b> (match whole line) options can be used with <b>-F</b>.
+They apply to each of the fixed strings. A line is selected if any of the fixed
+strings are found in it (subject to <b>-w</b> or <b>-x</b>, if present). This
+option applies only to the patterns that are matched against the contents of
+files; it does not apply to patterns specified by any of the <b>--include</b> or
+<b>--exclude</b> options.
+</P>
+<P>
+<b>-f</b> <i>filename</i>, <b>--file=</b><i>filename</i>
+Read patterns from the file, one per line, and match them against
+each line of input. What constitutes a newline when reading the file is the
+operating system's default. The <b>--newline</b> option has no effect on this
+option. Trailing white space is removed from each line, and blank lines are
+ignored. An empty file contains no patterns and therefore matches nothing. See
+also the comments about multiple patterns versus a single pattern with
+alternatives in the description of <b>-e</b> above.
+<br>
+<br>
+If this option is given more than once, all the specified files are
+read. A data line is output if any of the patterns match it. A filename can
+be given as "-" to refer to the standard input. When <b>-f</b> is used, patterns
+specified on the command line using <b>-e</b> may also be present; they are
+tested before the file's patterns. However, no other pattern is taken from the
+command line; all arguments are treated as the names of paths to be searched.
+</P>
+<P>
+<b>--file-list</b>=<i>filename</i>
+Read a list of files and/or directories that are to be scanned from the given
+file, one per line. Trailing white space is removed from each line, and blank
+lines are ignored. These paths are processed before any that are listed on the
+command line. The filename can be given as "-" to refer to the standard input.
+If <b>--file</b> and <b>--file-list</b> are both specified as "-", patterns are
+read first. This is useful only when the standard input is a terminal, from
+which further lines (the list of files) can be read after an end-of-file
+indication. If this option is given more than once, all the specified files are
+read.
+</P>
+<P>
+<b>--file-offsets</b>
+Instead of showing lines or parts of lines that match, show each match as an
+offset from the start of the file and a length, separated by a comma. In this
+mode, no context is shown. That is, the <b>-A</b>, <b>-B</b>, and <b>-C</b>
+options are ignored. If there is more than one match in a line, each of them is
+shown separately. This option is mutually exclusive with <b>--line-offsets</b>
+and <b>--only-matching</b>.
+</P>
+<P>
+<b>-H</b>, <b>--with-filename</b>
+Force the inclusion of the filename at the start of output lines when searching
+a single file. By default, the filename is not shown in this case. For matching
+lines, the filename is followed by a colon; for context lines, a hyphen
+separator is used. If a line number is also being output, it follows the file
+name.
+</P>
+<P>
+<b>-h</b>, <b>--no-filename</b>
+Suppress the output filenames when searching multiple files. By default,
+filenames are shown when multiple files are searched. For matching lines, the
+filename is followed by a colon; for context lines, a hyphen separator is used.
+If a line number is also being output, it follows the file name.
+</P>
+<P>
+<b>--help</b>
+Output a help message, giving brief details of the command options and file
+type support, and then exit. Anything else on the command line is
+ignored.
+</P>
+<P>
+<b>-I</b>
+Treat binary files as never matching. This is equivalent to
+<b>--binary-files</b>=<i>without-match</i>.
+</P>
+<P>
+<b>-i</b>, <b>--ignore-case</b>
+Ignore upper/lower case distinctions during comparisons.
+</P>
+<P>
+<b>--include</b>=<i>pattern</i>
+If any <b>--include</b> patterns are specified, the only files that are
+processed are those that match one of the patterns (and do not match an
+<b>--exclude</b> pattern). This option does not affect directories, but it
+applies to all files, whether listed on the command line, obtained from
+<b>--file-list</b>, or by scanning a directory. The pattern is a PCRE regular
+expression, and is matched against the final component of the file name, not
+the entire path. The <b>-F</b>, <b>-w</b>, and <b>-x</b> options do not apply to
+this pattern. The option may be given any number of times. If a file name
+matches both an <b>--include</b> and an <b>--exclude</b> pattern, it is excluded.
+There is no short form for this option.
+</P>
+<P>
+<b>--include-from=</b><i>filename</i>
+Treat each non-empty line of the file as the data for an <b>--include</b>
+option. What constitutes a newline for this purpose is the operating system's
+default. The <b>--newline</b> option has no effect on this option. This option
+may be given any number of times; all the files are read.
+</P>
+<P>
+<b>--include-dir</b>=<i>pattern</i>
+If any <b>--include-dir</b> patterns are specified, the only directories that
+are processed are those that match one of the patterns (and do not match an
+<b>--exclude-dir</b> pattern). This applies to all directories, whether listed
+on the command line, obtained from <b>--file-list</b>, or by scanning a parent
+directory. The pattern is a PCRE regular expression, and is matched against the
+final component of the directory name, not the entire path. The <b>-F</b>,
+<b>-w</b>, and <b>-x</b> options do not apply to this pattern. The option may be
+given any number of times. If a directory matches both <b>--include-dir</b> and
+<b>--exclude-dir</b>, it is excluded. There is no short form for this option.
+</P>
+<P>
+<b>-L</b>, <b>--files-without-match</b>
+Instead of outputting lines from the files, just output the names of the files
+that do not contain any lines that would have been output. Each file name is
+output once, on a separate line.
+</P>
+<P>
+<b>-l</b>, <b>--files-with-matches</b>
+Instead of outputting lines from the files, just output the names of the files
+containing lines that would have been output. Each file name is output
+once, on a separate line. Searching normally stops as soon as a matching line
+is found in a file. However, if the <b>-c</b> (count) option is also used,
+matching continues in order to obtain the correct count, and those files that
+have at least one match are listed along with their counts. Using this option
+with <b>-c</b> is a way of suppressing the listing of files with no matches.
+</P>
+<P>
+<b>--label</b>=<i>name</i>
+This option supplies a name to be used for the standard input when file names
+are being output. If not supplied, "(standard input)" is used. There is no
+short form for this option.
+</P>
+<P>
+<b>--line-buffered</b>
+When this option is given, input is read and processed line by line, and the
+output is flushed after each write. By default, input is read in large chunks,
+unless <b>pcregrep</b> can determine that it is reading from a terminal (which
+is currently possible only in Unix-like environments). Output to terminal is
+normally automatically flushed by the operating system. This option can be
+useful when the input or output is attached to a pipe and you do not want
+<b>pcregrep</b> to buffer up large amounts of data. However, its use will affect
+performance, and the <b>-M</b> (multiline) option ceases to work.
+</P>
+<P>
+<b>--line-offsets</b>
+Instead of showing lines or parts of lines that match, show each match as a
+line number, the offset from the start of the line, and a length. The line
+number is terminated by a colon (as usual; see the <b>-n</b> option), and the
+offset and length are separated by a comma. In this mode, no context is shown.
+That is, the <b>-A</b>, <b>-B</b>, and <b>-C</b> options are ignored. If there is
+more than one match in a line, each of them is shown separately. This option is
+mutually exclusive with <b>--file-offsets</b> and <b>--only-matching</b>.
+</P>
+<P>
+<b>--locale</b>=<i>locale-name</i>
+This option specifies a locale to be used for pattern matching. It overrides
+the value in the <b>LC_ALL</b> or <b>LC_CTYPE</b> environment variables. If no
+locale is specified, the PCRE library's default (usually the "C" locale) is
+used. There is no short form for this option.
+</P>
+<P>
+<b>--match-limit</b>=<i>number</i>
+Processing some regular expression patterns can require a very large amount of
+memory, leading in some cases to a program crash if not enough is available.
+Other patterns may take a very long time to search for all possible matching
+strings. The <b>pcre_exec()</b> function that is called by <b>pcregrep</b> to do
+the matching has two parameters that can limit the resources that it uses.
+<br>
+<br>
+The <b>--match-limit</b> option provides a means of limiting resource usage
+when processing patterns that are not going to match, but which have a very
+large number of possibilities in their search trees. The classic example is a
+pattern that uses nested unlimited repeats. Internally, PCRE uses a function
+called <b>match()</b> which it calls repeatedly (sometimes recursively). The
+limit set by <b>--match-limit</b> is imposed on the number of times this
+function is called during a match, which has the effect of limiting the amount
+of backtracking that can take place.
+<br>
+<br>
+The <b>--recursion-limit</b> option is similar to <b>--match-limit</b>, but
+instead of limiting the total number of times that <b>match()</b> is called, it
+limits the depth of recursive calls, which in turn limits the amount of memory
+that can be used. The recursion depth is a smaller number than the total number
+of calls, because not all calls to <b>match()</b> are recursive. This limit is
+of use only if it is set smaller than <b>--match-limit</b>.
+<br>
+<br>
+There are no short forms for these options. The default settings are specified
+when the PCRE library is compiled, with the default default being 10 million.
+</P>
+<P>
+<b>-M</b>, <b>--multiline</b>
+Allow patterns to match more than one line. When this option is given, patterns
+may usefully contain literal newline characters and internal occurrences of ^
+and $ characters. The output for a successful match may consist of more than
+one line, the last of which is the one in which the match ended. If the matched
+string ends with a newline sequence the output ends at the end of that line.
+<br>
+<br>
+When this option is set, the PCRE library is called in "multiline" mode.
+There is a limit to the number of lines that can be matched, imposed by the way
+that <b>pcregrep</b> buffers the input file as it scans it. However,
+<b>pcregrep</b> ensures that at least 8K characters or the rest of the document
+(whichever is the shorter) are available for forward matching, and similarly
+the previous 8K characters (or all the previous characters, if fewer than 8K)
+are guaranteed to be available for lookbehind assertions. This option does not
+work when input is read line by line (see \fP--line-buffered\fP.)
+</P>
+<P>
+<b>-N</b> <i>newline-type</i>, <b>--newline</b>=<i>newline-type</i>
+The PCRE library supports five different conventions for indicating
+the ends of lines. They are the single-character sequences CR (carriage return)
+and LF (linefeed), the two-character sequence CRLF, an "anycrlf" convention,
+which recognizes any of the preceding three types, and an "any" convention, in
+which any Unicode line ending sequence is assumed to end a line. The Unicode
+sequences are the three just mentioned, plus VT (vertical tab, U+000B), FF
+(form feed, U+000C), NEL (next line, U+0085), LS (line separator, U+2028), and
+PS (paragraph separator, U+2029).
+<br>
+<br>
+When the PCRE library is built, a default line-ending sequence is specified.
+This is normally the standard sequence for the operating system. Unless
+otherwise specified by this option, <b>pcregrep</b> uses the library's default.
+The possible values for this option are CR, LF, CRLF, ANYCRLF, or ANY. This
+makes it possible to use <b>pcregrep</b> to scan files that have come from other
+environments without having to modify their line endings. If the data that is
+being scanned does not agree with the convention set by this option,
+<b>pcregrep</b> may behave in strange ways. Note that this option does not
+apply to files specified by the <b>-f</b>, <b>--exclude-from</b>, or
+<b>--include-from</b> options, which are expected to use the operating system's
+standard newline sequence.
+</P>
+<P>
+<b>-n</b>, <b>--line-number</b>
+Precede each output line by its line number in the file, followed by a colon
+for matching lines or a hyphen for context lines. If the filename is also being
+output, it precedes the line number. This option is forced if
+<b>--line-offsets</b> is used.
+</P>
+<P>
+<b>--no-jit</b>
+If the PCRE library is built with support for just-in-time compiling (which
+speeds up matching), <b>pcregrep</b> automatically makes use of this, unless it
+was explicitly disabled at build time. This option can be used to disable the
+use of JIT at run time. It is provided for testing and working round problems.
+It should never be needed in normal use.
+</P>
+<P>
+<b>-o</b>, <b>--only-matching</b>
+Show only the part of the line that matched a pattern instead of the whole
+line. In this mode, no context is shown. That is, the <b>-A</b>, <b>-B</b>, and
+<b>-C</b> options are ignored. If there is more than one match in a line, each
+of them is shown separately. If <b>-o</b> is combined with <b>-v</b> (invert the
+sense of the match to find non-matching lines), no output is generated, but the
+return code is set appropriately. If the matched portion of the line is empty,
+nothing is output unless the file name or line number are being printed, in
+which case they are shown on an otherwise empty line. This option is mutually
+exclusive with <b>--file-offsets</b> and <b>--line-offsets</b>.
+</P>
+<P>
+<b>-o</b><i>number</i>, <b>--only-matching</b>=<i>number</i>
+Show only the part of the line that matched the capturing parentheses of the
+given number. Up to 32 capturing parentheses are supported, and -o0 is
+equivalent to <b>-o</b> without a number. Because these options can be given
+without an argument (see above), if an argument is present, it must be given in
+the same shell item, for example, -o3 or --only-matching=2. The comments given
+for the non-argument case above also apply to this case. If the specified
+capturing parentheses do not exist in the pattern, or were not set in the
+match, nothing is output unless the file name or line number are being printed.
+<br>
+<br>
+If this option is given multiple times, multiple substrings are output, in the
+order the options are given. For example, -o3 -o1 -o3 causes the substrings
+matched by capturing parentheses 3 and 1 and then 3 again to be output. By
+default, there is no separator (but see the next option).
+</P>
+<P>
+<b>--om-separator</b>=<i>text</i>
+Specify a separating string for multiple occurrences of <b>-o</b>. The default
+is an empty string. Separating strings are never coloured.
+</P>
+<P>
+<b>-q</b>, <b>--quiet</b>
+Work quietly, that is, display nothing except error messages. The exit
+status indicates whether or not any matches were found.
+</P>
+<P>
+<b>-r</b>, <b>--recursive</b>
+If any given path is a directory, recursively scan the files it contains,
+taking note of any <b>--include</b> and <b>--exclude</b> settings. By default, a
+directory is read as a normal file; in some operating systems this gives an
+immediate end-of-file. This option is a shorthand for setting the <b>-d</b>
+option to "recurse".
+</P>
+<P>
+<b>--recursion-limit</b>=<i>number</i>
+See <b>--match-limit</b> above.
+</P>
+<P>
+<b>-s</b>, <b>--no-messages</b>
+Suppress error messages about non-existent or unreadable files. Such files are
+quietly skipped. However, the return code is still 2, even if matches were
+found in other files.
+</P>
+<P>
+<b>-u</b>, <b>--utf-8</b>
+Operate in UTF-8 mode. This option is available only if PCRE has been compiled
+with UTF-8 support. All patterns (including those for any <b>--exclude</b> and
+<b>--include</b> options) and all subject lines that are scanned must be valid
+strings of UTF-8 characters.
+</P>
+<P>
+<b>-V</b>, <b>--version</b>
+Write the version numbers of <b>pcregrep</b> and the PCRE library to the
+standard output and then exit. Anything else on the command line is
+ignored.
+</P>
+<P>
+<b>-v</b>, <b>--invert-match</b>
+Invert the sense of the match, so that lines which do <i>not</i> match any of
+the patterns are the ones that are found.
+</P>
+<P>
+<b>-w</b>, <b>--word-regex</b>, <b>--word-regexp</b>
+Force the patterns to match only whole words. This is equivalent to having \b
+at the start and end of the pattern. This option applies only to the patterns
+that are matched against the contents of files; it does not apply to patterns
+specified by any of the <b>--include</b> or <b>--exclude</b> options.
+</P>
+<P>
+<b>-x</b>, <b>--line-regex</b>, <b>--line-regexp</b>
+Force the patterns to be anchored (each must start matching at the beginning of
+a line) and in addition, require them to match entire lines. This is equivalent
+to having ^ and $ characters at the start and end of each alternative branch in
+every pattern. This option applies only to the patterns that are matched
+against the contents of files; it does not apply to patterns specified by any
+of the <b>--include</b> or <b>--exclude</b> options.
+</P>
+<br><a name="SEC6" href="#TOC1">ENVIRONMENT VARIABLES</a><br>
+<P>
+The environment variables <b>LC_ALL</b> and <b>LC_CTYPE</b> are examined, in that
+order, for a locale. The first one that is set is used. This can be overridden
+by the <b>--locale</b> option. If no locale is set, the PCRE library's default
+(usually the "C" locale) is used.
+</P>
+<br><a name="SEC7" href="#TOC1">NEWLINES</a><br>
+<P>
+The <b>-N</b> (<b>--newline</b>) option allows <b>pcregrep</b> to scan files with
+different newline conventions from the default. Any parts of the input files
+that are written to the standard output are copied identically, with whatever
+newline sequences they have in the input. However, the setting of this option
+does not affect the interpretation of files specified by the <b>-f</b>,
+<b>--exclude-from</b>, or <b>--include-from</b> options, which are assumed to use
+the operating system's standard newline sequence, nor does it affect the way in
+which <b>pcregrep</b> writes informational messages to the standard error and
+output streams. For these it uses the string "\n" to indicate newlines,
+relying on the C I/O library to convert this to an appropriate sequence.
+</P>
+<br><a name="SEC8" href="#TOC1">OPTIONS COMPATIBILITY</a><br>
+<P>
+Many of the short and long forms of <b>pcregrep</b>'s options are the same
+as in the GNU <b>grep</b> program. Any long option of the form
+<b>--xxx-regexp</b> (GNU terminology) is also available as <b>--xxx-regex</b>
+(PCRE terminology). However, the <b>--file-list</b>, <b>--file-offsets</b>,
+<b>--include-dir</b>, <b>--line-offsets</b>, <b>--locale</b>, <b>--match-limit</b>,
+<b>-M</b>, <b>--multiline</b>, <b>-N</b>, <b>--newline</b>, <b>--om-separator</b>,
+<b>--recursion-limit</b>, <b>-u</b>, and <b>--utf-8</b> options are specific to
+<b>pcregrep</b>, as is the use of the <b>--only-matching</b> option with a
+capturing parentheses number.
+</P>
+<P>
+Although most of the common options work the same way, a few are different in
+<b>pcregrep</b>. For example, the <b>--include</b> option's argument is a glob
+for GNU <b>grep</b>, but a regular expression for <b>pcregrep</b>. If both the
+<b>-c</b> and <b>-l</b> options are given, GNU grep lists only file names,
+without counts, but <b>pcregrep</b> gives the counts.
+</P>
+<br><a name="SEC9" href="#TOC1">OPTIONS WITH DATA</a><br>
+<P>
+There are four different ways in which an option with data can be specified.
+If a short form option is used, the data may follow immediately, or (with one
+exception) in the next command line item. For example:
+<pre>
+  -f/some/file
+  -f /some/file
+</pre>
+The exception is the <b>-o</b> option, which may appear with or without data.
+Because of this, if data is present, it must follow immediately in the same
+item, for example -o3.
+</P>
+<P>
+If a long form option is used, the data may appear in the same command line
+item, separated by an equals character, or (with two exceptions) it may appear
+in the next command line item. For example:
+<pre>
+  --file=/some/file
+  --file /some/file
+</pre>
+Note, however, that if you want to supply a file name beginning with ~ as data
+in a shell command, and have the shell expand ~ to a home directory, you must
+separate the file name from the option, because the shell does not treat ~
+specially unless it is at the start of an item.
+</P>
+<P>
+The exceptions to the above are the <b>--colour</b> (or <b>--color</b>) and
+<b>--only-matching</b> options, for which the data is optional. If one of these
+options does have data, it must be given in the first form, using an equals
+character. Otherwise <b>pcregrep</b> will assume that it has no data.
+</P>
+<br><a name="SEC10" href="#TOC1">MATCHING ERRORS</a><br>
+<P>
+It is possible to supply a regular expression that takes a very long time to
+fail to match certain lines. Such patterns normally involve nested indefinite
+repeats, for example: (a+)*\d when matched against a line of a's with no final
+digit. The PCRE matching function has a resource limit that causes it to abort
+in these circumstances. If this happens, <b>pcregrep</b> outputs an error
+message and the line that caused the problem to the standard error stream. If
+there are more than 20 such errors, <b>pcregrep</b> gives up.
+</P>
+<P>
+The <b>--match-limit</b> option of <b>pcregrep</b> can be used to set the overall
+resource limit; there is a second option called <b>--recursion-limit</b> that
+sets a limit on the amount of memory (usually stack) that is used (see the
+discussion of these options above).
+</P>
+<br><a name="SEC11" href="#TOC1">DIAGNOSTICS</a><br>
+<P>
+Exit status is 0 if any matches were found, 1 if no matches were found, and 2
+for syntax errors, overlong lines, non-existent or inaccessible files (even if
+matches were found in other files) or too many matching errors. Using the
+<b>-s</b> option to suppress error messages about inaccessible files does not
+affect the return code.
+</P>
+<br><a name="SEC12" href="#TOC1">SEE ALSO</a><br>
+<P>
+<b>pcrepattern</b>(3), <b>pcresyntax</b>(3), <b>pcretest</b>(1).
+</P>
+<br><a name="SEC13" href="#TOC1">AUTHOR</a><br>
+<P>
+Philip Hazel
+<br>
+University Computing Service
+<br>
+Cambridge CB2 3QH, England.
+<br>
+</P>
+<br><a name="SEC14" href="#TOC1">REVISION</a><br>
+<P>
+Last updated: 03 April 2014
+<br>
+Copyright &copy; 1997-2014 University of Cambridge.
+<br>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcrejit.html b/libs/Pcre16/docs/doc/html/pcrejit.html
new file mode 100644
index 0000000000..210f1da026
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcrejit.html
@@ -0,0 +1,452 @@
+<html>
+<head>
+<title>pcrejit specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcrejit man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<ul>
+<li><a name="TOC1" href="#SEC1">PCRE JUST-IN-TIME COMPILER SUPPORT</a>
+<li><a name="TOC2" href="#SEC2">8-BIT, 16-BIT AND 32-BIT SUPPORT</a>
+<li><a name="TOC3" href="#SEC3">AVAILABILITY OF JIT SUPPORT</a>
+<li><a name="TOC4" href="#SEC4">SIMPLE USE OF JIT</a>
+<li><a name="TOC5" href="#SEC5">UNSUPPORTED OPTIONS AND PATTERN ITEMS</a>
+<li><a name="TOC6" href="#SEC6">RETURN VALUES FROM JIT EXECUTION</a>
+<li><a name="TOC7" href="#SEC7">SAVING AND RESTORING COMPILED PATTERNS</a>
+<li><a name="TOC8" href="#SEC8">CONTROLLING THE JIT STACK</a>
+<li><a name="TOC9" href="#SEC9">JIT STACK FAQ</a>
+<li><a name="TOC10" href="#SEC10">EXAMPLE CODE</a>
+<li><a name="TOC11" href="#SEC11">JIT FAST PATH API</a>
+<li><a name="TOC12" href="#SEC12">SEE ALSO</a>
+<li><a name="TOC13" href="#SEC13">AUTHOR</a>
+<li><a name="TOC14" href="#SEC14">REVISION</a>
+</ul>
+<br><a name="SEC1" href="#TOC1">PCRE JUST-IN-TIME COMPILER SUPPORT</a><br>
+<P>
+Just-in-time compiling is a heavyweight optimization that can greatly speed up
+pattern matching. However, it comes at the cost of extra processing before the
+match is performed. Therefore, it is of most benefit when the same pattern is
+going to be matched many times. This does not necessarily mean many calls of a
+matching function; if the pattern is not anchored, matching attempts may take
+place many times at various positions in the subject, even for a single call.
+Therefore, if the subject string is very long, it may still pay to use JIT for
+one-off matches.
+</P>
+<P>
+JIT support applies only to the traditional Perl-compatible matching function.
+It does not apply when the DFA matching function is being used. The code for
+this support was written by Zoltan Herczeg.
+</P>
+<br><a name="SEC2" href="#TOC1">8-BIT, 16-BIT AND 32-BIT SUPPORT</a><br>
+<P>
+JIT support is available for all of the 8-bit, 16-bit and 32-bit PCRE
+libraries. To keep this documentation simple, only the 8-bit interface is
+described in what follows. If you are using the 16-bit library, substitute the
+16-bit functions and 16-bit structures (for example, <i>pcre16_jit_stack</i>
+instead of <i>pcre_jit_stack</i>). If you are using the 32-bit library,
+substitute the 32-bit functions and 32-bit structures (for example,
+<i>pcre32_jit_stack</i> instead of <i>pcre_jit_stack</i>).
+</P>
+<br><a name="SEC3" href="#TOC1">AVAILABILITY OF JIT SUPPORT</a><br>
+<P>
+JIT support is an optional feature of PCRE. The "configure" option --enable-jit
+(or equivalent CMake option) must be set when PCRE is built if you want to use
+JIT. The support is limited to the following hardware platforms:
+<pre>
+  ARM v5, v7, and Thumb2
+  Intel x86 32-bit and 64-bit
+  MIPS 32-bit
+  Power PC 32-bit and 64-bit
+  SPARC 32-bit (experimental)
+</pre>
+If --enable-jit is set on an unsupported platform, compilation fails.
+</P>
+<P>
+A program that is linked with PCRE 8.20 or later can tell if JIT support is
+available by calling <b>pcre_config()</b> with the PCRE_CONFIG_JIT option. The
+result is 1 when JIT is available, and 0 otherwise. However, a simple program
+does not need to check this in order to use JIT. The normal API is implemented
+in a way that falls back to the interpretive code if JIT is not available. For
+programs that need the best possible performance, there is also a "fast path"
+API that is JIT-specific.
+</P>
+<P>
+If your program may sometimes be linked with versions of PCRE that are older
+than 8.20, but you want to use JIT when it is available, you can test
+the values of PCRE_MAJOR and PCRE_MINOR, or the existence of a JIT macro such
+as PCRE_CONFIG_JIT, for compile-time control of your code.
+</P>
+<br><a name="SEC4" href="#TOC1">SIMPLE USE OF JIT</a><br>
+<P>
+You have to do two things to make use of the JIT support in the simplest way:
+<pre>
+  (1) Call <b>pcre_study()</b> with the PCRE_STUDY_JIT_COMPILE option for
+      each compiled pattern, and pass the resulting <b>pcre_extra</b> block to
+      <b>pcre_exec()</b>.
+
+  (2) Use <b>pcre_free_study()</b> to free the <b>pcre_extra</b> block when it is
+      no longer needed, instead of just freeing it yourself. This ensures that
+      any JIT data is also freed.
+</pre>
+For a program that may be linked with pre-8.20 versions of PCRE, you can insert
+<pre>
+  #ifndef PCRE_STUDY_JIT_COMPILE
+  #define PCRE_STUDY_JIT_COMPILE 0
+  #endif
+</pre>
+so that no option is passed to <b>pcre_study()</b>, and then use something like
+this to free the study data:
+<pre>
+  #ifdef PCRE_CONFIG_JIT
+      pcre_free_study(study_ptr);
+  #else
+      pcre_free(study_ptr);
+  #endif
+</pre>
+PCRE_STUDY_JIT_COMPILE requests the JIT compiler to generate code for complete
+matches. If you want to run partial matches using the PCRE_PARTIAL_HARD or
+PCRE_PARTIAL_SOFT options of <b>pcre_exec()</b>, you should set one or both of
+the following options in addition to, or instead of, PCRE_STUDY_JIT_COMPILE
+when you call <b>pcre_study()</b>:
+<pre>
+  PCRE_STUDY_JIT_PARTIAL_HARD_COMPILE
+  PCRE_STUDY_JIT_PARTIAL_SOFT_COMPILE
+</pre>
+The JIT compiler generates different optimized code for each of the three
+modes (normal, soft partial, hard partial). When <b>pcre_exec()</b> is called,
+the appropriate code is run if it is available. Otherwise, the pattern is
+matched using interpretive code.
+</P>
+<P>
+In some circumstances you may need to call additional functions. These are
+described in the section entitled
+<a href="#stackcontrol">"Controlling the JIT stack"</a>
+below.
+</P>
+<P>
+If JIT support is not available, PCRE_STUDY_JIT_COMPILE etc. are ignored, and
+no JIT data is created. Otherwise, the compiled pattern is passed to the JIT
+compiler, which turns it into machine code that executes much faster than the
+normal interpretive code. When <b>pcre_exec()</b> is passed a <b>pcre_extra</b>
+block containing a pointer to JIT code of the appropriate mode (normal or
+hard/soft partial), it obeys that code instead of running the interpreter. The
+result is identical, but the compiled JIT code runs much faster.
+</P>
+<P>
+There are some <b>pcre_exec()</b> options that are not supported for JIT
+execution. There are also some pattern items that JIT cannot handle. Details
+are given below. In both cases, execution automatically falls back to the
+interpretive code. If you want to know whether JIT was actually used for a
+particular match, you should arrange for a JIT callback function to be set up
+as described in the section entitled
+<a href="#stackcontrol">"Controlling the JIT stack"</a>
+below, even if you do not need to supply a non-default JIT stack. Such a
+callback function is called whenever JIT code is about to be obeyed. If the
+execution options are not right for JIT execution, the callback function is not
+obeyed.
+</P>
+<P>
+If the JIT compiler finds an unsupported item, no JIT data is generated. You
+can find out if JIT execution is available after studying a pattern by calling
+<b>pcre_fullinfo()</b> with the PCRE_INFO_JIT option. A result of 1 means that
+JIT compilation was successful. A result of 0 means that JIT support is not
+available, or the pattern was not studied with PCRE_STUDY_JIT_COMPILE etc., or
+the JIT compiler was not able to handle the pattern.
+</P>
+<P>
+Once a pattern has been studied, with or without JIT, it can be used as many
+times as you like for matching different subject strings.
+</P>
+<br><a name="SEC5" href="#TOC1">UNSUPPORTED OPTIONS AND PATTERN ITEMS</a><br>
+<P>
+The only <b>pcre_exec()</b> options that are supported for JIT execution are
+PCRE_NO_UTF8_CHECK, PCRE_NO_UTF16_CHECK, PCRE_NO_UTF32_CHECK, PCRE_NOTBOL,
+PCRE_NOTEOL, PCRE_NOTEMPTY, PCRE_NOTEMPTY_ATSTART, PCRE_PARTIAL_HARD, and
+PCRE_PARTIAL_SOFT.
+</P>
+<P>
+The only unsupported pattern items are \C (match a single data unit) when
+running in a UTF mode, and a callout immediately before an assertion condition
+in a conditional group.
+</P>
+<br><a name="SEC6" href="#TOC1">RETURN VALUES FROM JIT EXECUTION</a><br>
+<P>
+When a pattern is matched using JIT execution, the return values are the same
+as those given by the interpretive <b>pcre_exec()</b> code, with the addition of
+one new error code: PCRE_ERROR_JIT_STACKLIMIT. This means that the memory used
+for the JIT stack was insufficient. See
+<a href="#stackcontrol">"Controlling the JIT stack"</a>
+below for a discussion of JIT stack usage. For compatibility with the
+interpretive <b>pcre_exec()</b> code, no more than two-thirds of the
+<i>ovector</i> argument is used for passing back captured substrings.
+</P>
+<P>
+The error code PCRE_ERROR_MATCHLIMIT is returned by the JIT code if searching a
+very large pattern tree goes on for too long, as it is in the same circumstance
+when JIT is not used, but the details of exactly what is counted are not the
+same. The PCRE_ERROR_RECURSIONLIMIT error code is never returned by JIT
+execution.
+</P>
+<br><a name="SEC7" href="#TOC1">SAVING AND RESTORING COMPILED PATTERNS</a><br>
+<P>
+The code that is generated by the JIT compiler is architecture-specific, and is
+also position dependent. For those reasons it cannot be saved (in a file or
+database) and restored later like the bytecode and other data of a compiled
+pattern. Saving and restoring compiled patterns is not something many people
+do. More detail about this facility is given in the
+<a href="pcreprecompile.html"><b>pcreprecompile</b></a>
+documentation. It should be possible to run <b>pcre_study()</b> on a saved and
+restored pattern, and thereby recreate the JIT data, but because JIT
+compilation uses significant resources, it is probably not worth doing this;
+you might as well recompile the original pattern.
+<a name="stackcontrol"></a></P>
+<br><a name="SEC8" href="#TOC1">CONTROLLING THE JIT STACK</a><br>
+<P>
+When the compiled JIT code runs, it needs a block of memory to use as a stack.
+By default, it uses 32K on the machine stack. However, some large or
+complicated patterns need more than this. The error PCRE_ERROR_JIT_STACKLIMIT
+is given when there is not enough stack. Three functions are provided for
+managing blocks of memory for use as JIT stacks. There is further discussion
+about the use of JIT stacks in the section entitled
+<a href="#stackcontrol">"JIT stack FAQ"</a>
+below.
+</P>
+<P>
+The <b>pcre_jit_stack_alloc()</b> function creates a JIT stack. Its arguments
+are a starting size and a maximum size, and it returns a pointer to an opaque
+structure of type <b>pcre_jit_stack</b>, or NULL if there is an error. The
+<b>pcre_jit_stack_free()</b> function can be used to free a stack that is no
+longer needed. (For the technically minded: the address space is allocated by
+mmap or VirtualAlloc.)
+</P>
+<P>
+JIT uses far less memory for recursion than the interpretive code,
+and a maximum stack size of 512K to 1M should be more than enough for any
+pattern.
+</P>
+<P>
+The <b>pcre_assign_jit_stack()</b> function specifies which stack JIT code
+should use. Its arguments are as follows:
+<pre>
+  pcre_extra         *extra
+  pcre_jit_callback  callback
+  void               *data
+</pre>
+The <i>extra</i> argument must be the result of studying a pattern with
+PCRE_STUDY_JIT_COMPILE etc. There are three cases for the values of the other
+two options:
+<pre>
+  (1) If <i>callback</i> is NULL and <i>data</i> is NULL, an internal 32K block
+      on the machine stack is used.
+
+  (2) If <i>callback</i> is NULL and <i>data</i> is not NULL, <i>data</i> must be
+      a valid JIT stack, the result of calling <b>pcre_jit_stack_alloc()</b>.
+
+  (3) If <i>callback</i> is not NULL, it must point to a function that is
+      called with <i>data</i> as an argument at the start of matching, in
+      order to set up a JIT stack. If the return from the callback
+      function is NULL, the internal 32K stack is used; otherwise the
+      return value must be a valid JIT stack, the result of calling
+      <b>pcre_jit_stack_alloc()</b>.
+</pre>
+A callback function is obeyed whenever JIT code is about to be run; it is not
+obeyed when <b>pcre_exec()</b> is called with options that are incompatible for
+JIT execution. A callback function can therefore be used to determine whether a
+match operation was executed by JIT or by the interpreter.
+</P>
+<P>
+You may safely use the same JIT stack for more than one pattern (either by
+assigning directly or by callback), as long as the patterns are all matched
+sequentially in the same thread. In a multithread application, if you do not
+specify a JIT stack, or if you assign or pass back NULL from a callback, that
+is thread-safe, because each thread has its own machine stack. However, if you
+assign or pass back a non-NULL JIT stack, this must be a different stack for
+each thread so that the application is thread-safe.
+</P>
+<P>
+Strictly speaking, even more is allowed. You can assign the same non-NULL stack
+to any number of patterns as long as they are not used for matching by multiple
+threads at the same time. For example, you can assign the same stack to all
+compiled patterns, and use a global mutex in the callback to wait until the
+stack is available for use. However, this is an inefficient solution, and not
+recommended.
+</P>
+<P>
+This is a suggestion for how a multithreaded program that needs to set up
+non-default JIT stacks might operate:
+<pre>
+  During thread initalization
+    thread_local_var = pcre_jit_stack_alloc(...)
+
+  During thread exit
+    pcre_jit_stack_free(thread_local_var)
+
+  Use a one-line callback function
+    return thread_local_var
+</pre>
+All the functions described in this section do nothing if JIT is not available,
+and <b>pcre_assign_jit_stack()</b> does nothing unless the <b>extra</b> argument
+is non-NULL and points to a <b>pcre_extra</b> block that is the result of a
+successful study with PCRE_STUDY_JIT_COMPILE etc.
+<a name="stackfaq"></a></P>
+<br><a name="SEC9" href="#TOC1">JIT STACK FAQ</a><br>
+<P>
+(1) Why do we need JIT stacks?
+<br>
+<br>
+PCRE (and JIT) is a recursive, depth-first engine, so it needs a stack where
+the local data of the current node is pushed before checking its child nodes.
+Allocating real machine stack on some platforms is difficult. For example, the
+stack chain needs to be updated every time if we extend the stack on PowerPC.
+Although it is possible, its updating time overhead decreases performance. So
+we do the recursion in memory.
+</P>
+<P>
+(2) Why don't we simply allocate blocks of memory with <b>malloc()</b>?
+<br>
+<br>
+Modern operating systems have a nice feature: they can reserve an address space
+instead of allocating memory. We can safely allocate memory pages inside this
+address space, so the stack could grow without moving memory data (this is
+important because of pointers). Thus we can allocate 1M address space, and use
+only a single memory page (usually 4K) if that is enough. However, we can still
+grow up to 1M anytime if needed.
+</P>
+<P>
+(3) Who "owns" a JIT stack?
+<br>
+<br>
+The owner of the stack is the user program, not the JIT studied pattern or
+anything else. The user program must ensure that if a stack is used by
+<b>pcre_exec()</b>, (that is, it is assigned to the pattern currently running),
+that stack must not be used by any other threads (to avoid overwriting the same
+memory area). The best practice for multithreaded programs is to allocate a
+stack for each thread, and return this stack through the JIT callback function.
+</P>
+<P>
+(4) When should a JIT stack be freed?
+<br>
+<br>
+You can free a JIT stack at any time, as long as it will not be used by
+<b>pcre_exec()</b> again. When you assign the stack to a pattern, only a pointer
+is set. There is no reference counting or any other magic. You can free the
+patterns and stacks in any order, anytime. Just <i>do not</i> call
+<b>pcre_exec()</b> with a pattern pointing to an already freed stack, as that
+will cause SEGFAULT. (Also, do not free a stack currently used by
+<b>pcre_exec()</b> in another thread). You can also replace the stack for a
+pattern at any time. You can even free the previous stack before assigning a
+replacement.
+</P>
+<P>
+(5) Should I allocate/free a stack every time before/after calling
+<b>pcre_exec()</b>?
+<br>
+<br>
+No, because this is too costly in terms of resources. However, you could
+implement some clever idea which release the stack if it is not used in let's
+say two minutes. The JIT callback can help to achieve this without keeping a
+list of the currently JIT studied patterns.
+</P>
+<P>
+(6) OK, the stack is for long term memory allocation. But what happens if a
+pattern causes stack overflow with a stack of 1M? Is that 1M kept until the
+stack is freed?
+<br>
+<br>
+Especially on embedded sytems, it might be a good idea to release memory
+sometimes without freeing the stack. There is no API for this at the moment.
+Probably a function call which returns with the currently allocated memory for
+any stack and another which allows releasing memory (shrinking the stack) would
+be a good idea if someone needs this.
+</P>
+<P>
+(7) This is too much of a headache. Isn't there any better solution for JIT
+stack handling?
+<br>
+<br>
+No, thanks to Windows. If POSIX threads were used everywhere, we could throw
+out this complicated API.
+</P>
+<br><a name="SEC10" href="#TOC1">EXAMPLE CODE</a><br>
+<P>
+This is a single-threaded example that specifies a JIT stack without using a
+callback.
+<pre>
+  int rc;
+  int ovector[30];
+  pcre *re;
+  pcre_extra *extra;
+  pcre_jit_stack *jit_stack;
+
+  re = pcre_compile(pattern, 0, &error, &erroffset, NULL);
+  /* Check for errors */
+  extra = pcre_study(re, PCRE_STUDY_JIT_COMPILE, &error);
+  jit_stack = pcre_jit_stack_alloc(32*1024, 512*1024);
+  /* Check for error (NULL) */
+  pcre_assign_jit_stack(extra, NULL, jit_stack);
+  rc = pcre_exec(re, extra, subject, length, 0, 0, ovector, 30);
+  /* Check results */
+  pcre_free(re);
+  pcre_free_study(extra);
+  pcre_jit_stack_free(jit_stack);
+
+</PRE>
+</P>
+<br><a name="SEC11" href="#TOC1">JIT FAST PATH API</a><br>
+<P>
+Because the API described above falls back to interpreted execution when JIT is
+not available, it is convenient for programs that are written for general use
+in many environments. However, calling JIT via <b>pcre_exec()</b> does have a
+performance impact. Programs that are written for use where JIT is known to be
+available, and which need the best possible performance, can instead use a
+"fast path" API to call JIT execution directly instead of calling
+<b>pcre_exec()</b> (obviously only for patterns that have been successfully
+studied by JIT).
+</P>
+<P>
+The fast path function is called <b>pcre_jit_exec()</b>, and it takes exactly
+the same arguments as <b>pcre_exec()</b>, plus one additional argument that
+must point to a JIT stack. The JIT stack arrangements described above do not
+apply. The return values are the same as for <b>pcre_exec()</b>.
+</P>
+<P>
+When you call <b>pcre_exec()</b>, as well as testing for invalid options, a
+number of other sanity checks are performed on the arguments. For example, if
+the subject pointer is NULL, or its length is negative, an immediate error is
+given. Also, unless PCRE_NO_UTF[8|16|32] is set, a UTF subject string is tested
+for validity. In the interests of speed, these checks do not happen on the JIT
+fast path, and if invalid data is passed, the result is undefined.
+</P>
+<P>
+Bypassing the sanity checks and the <b>pcre_exec()</b> wrapping can give
+speedups of more than 10%.
+</P>
+<br><a name="SEC12" href="#TOC1">SEE ALSO</a><br>
+<P>
+<b>pcreapi</b>(3)
+</P>
+<br><a name="SEC13" href="#TOC1">AUTHOR</a><br>
+<P>
+Philip Hazel (FAQ by Zoltan Herczeg)
+<br>
+University Computing Service
+<br>
+Cambridge CB2 3QH, England.
+<br>
+</P>
+<br><a name="SEC14" href="#TOC1">REVISION</a><br>
+<P>
+Last updated: 17 March 2013
+<br>
+Copyright &copy; 1997-2013 University of Cambridge.
+<br>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcrelimits.html b/libs/Pcre16/docs/doc/html/pcrelimits.html
new file mode 100644
index 0000000000..ee5ebf033d
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcrelimits.html
@@ -0,0 +1,90 @@
+<html>
+<head>
+<title>pcrelimits specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcrelimits man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<br><b>
+SIZE AND OTHER LIMITATIONS
+</b><br>
+<P>
+There are some size limitations in PCRE but it is hoped that they will never in
+practice be relevant.
+</P>
+<P>
+The maximum length of a compiled pattern is approximately 64K data units (bytes
+for the 8-bit library, 16-bit units for the 16-bit library, and 32-bit units for
+the 32-bit library) if PCRE is compiled with the default internal linkage size,
+which is 2 bytes for the 8-bit and 16-bit libraries, and 4 bytes for the 32-bit
+library. If you want to process regular expressions that are truly enormous,
+you can compile PCRE with an internal linkage size of 3 or 4 (when building the
+16-bit or 32-bit library, 3 is rounded up to 4). See the <b>README</b> file in
+the source distribution and the
+<a href="pcrebuild.html"><b>pcrebuild</b></a>
+documentation for details. In these cases the limit is substantially larger.
+However, the speed of execution is slower.
+</P>
+<P>
+All values in repeating quantifiers must be less than 65536.
+</P>
+<P>
+There is no limit to the number of parenthesized subpatterns, but there can be
+no more than 65535 capturing subpatterns. There is, however, a limit to the
+depth of nesting of parenthesized subpatterns of all kinds. This is imposed in
+order to limit the amount of system stack used at compile time. The limit can
+be specified when PCRE is built; the default is 250.
+</P>
+<P>
+There is a limit to the number of forward references to subsequent subpatterns
+of around 200,000. Repeated forward references with fixed upper limits, for
+example, (?2){0,100} when subpattern number 2 is to the right, are included in
+the count. There is no limit to the number of backward references.
+</P>
+<P>
+The maximum length of name for a named subpattern is 32 characters, and the
+maximum number of named subpatterns is 10000.
+</P>
+<P>
+The maximum length of a name in a (*MARK), (*PRUNE), (*SKIP), or (*THEN) verb
+is 255 for the 8-bit library and 65535 for the 16-bit and 32-bit libraries.
+</P>
+<P>
+The maximum length of a subject string is the largest positive number that an
+integer variable can hold. However, when using the traditional matching
+function, PCRE uses recursion to handle subpatterns and indefinite repetition.
+This means that the available stack space may limit the size of a subject
+string that can be processed by certain patterns. For a discussion of stack
+issues, see the
+<a href="pcrestack.html"><b>pcrestack</b></a>
+documentation.
+</P>
+<br><b>
+AUTHOR
+</b><br>
+<P>
+Philip Hazel
+<br>
+University Computing Service
+<br>
+Cambridge CB2 3QH, England.
+<br>
+</P>
+<br><b>
+REVISION
+</b><br>
+<P>
+Last updated: 05 November 2013
+<br>
+Copyright &copy; 1997-2013 University of Cambridge.
+<br>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcrematching.html b/libs/Pcre16/docs/doc/html/pcrematching.html
new file mode 100644
index 0000000000..a1af39b68d
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcrematching.html
@@ -0,0 +1,242 @@
+<html>
+<head>
+<title>pcrematching specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcrematching man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<ul>
+<li><a name="TOC1" href="#SEC1">PCRE MATCHING ALGORITHMS</a>
+<li><a name="TOC2" href="#SEC2">REGULAR EXPRESSIONS AS TREES</a>
+<li><a name="TOC3" href="#SEC3">THE STANDARD MATCHING ALGORITHM</a>
+<li><a name="TOC4" href="#SEC4">THE ALTERNATIVE MATCHING ALGORITHM</a>
+<li><a name="TOC5" href="#SEC5">ADVANTAGES OF THE ALTERNATIVE ALGORITHM</a>
+<li><a name="TOC6" href="#SEC6">DISADVANTAGES OF THE ALTERNATIVE ALGORITHM</a>
+<li><a name="TOC7" href="#SEC7">AUTHOR</a>
+<li><a name="TOC8" href="#SEC8">REVISION</a>
+</ul>
+<br><a name="SEC1" href="#TOC1">PCRE MATCHING ALGORITHMS</a><br>
+<P>
+This document describes the two different algorithms that are available in PCRE
+for matching a compiled regular expression against a given subject string. The
+"standard" algorithm is the one provided by the <b>pcre_exec()</b>,
+<b>pcre16_exec()</b> and <b>pcre32_exec()</b> functions. These work in the same
+as as Perl's matching function, and provide a Perl-compatible matching operation.
+The just-in-time (JIT) optimization that is described in the
+<a href="pcrejit.html"><b>pcrejit</b></a>
+documentation is compatible with these functions.
+</P>
+<P>
+An alternative algorithm is provided by the <b>pcre_dfa_exec()</b>,
+<b>pcre16_dfa_exec()</b> and <b>pcre32_dfa_exec()</b> functions; they operate in
+a different way, and are not Perl-compatible. This alternative has advantages
+and disadvantages compared with the standard algorithm, and these are described
+below.
+</P>
+<P>
+When there is only one possible way in which a given subject string can match a
+pattern, the two algorithms give the same answer. A difference arises, however,
+when there are multiple possibilities. For example, if the pattern
+<pre>
+  ^&#60;.*&#62;
+</pre>
+is matched against the string
+<pre>
+  &#60;something&#62; &#60;something else&#62; &#60;something further&#62;
+</pre>
+there are three possible answers. The standard algorithm finds only one of
+them, whereas the alternative algorithm finds all three.
+</P>
+<br><a name="SEC2" href="#TOC1">REGULAR EXPRESSIONS AS TREES</a><br>
+<P>
+The set of strings that are matched by a regular expression can be represented
+as a tree structure. An unlimited repetition in the pattern makes the tree of
+infinite size, but it is still a tree. Matching the pattern to a given subject
+string (from a given starting point) can be thought of as a search of the tree.
+There are two ways to search a tree: depth-first and breadth-first, and these
+correspond to the two matching algorithms provided by PCRE.
+</P>
+<br><a name="SEC3" href="#TOC1">THE STANDARD MATCHING ALGORITHM</a><br>
+<P>
+In the terminology of Jeffrey Friedl's book "Mastering Regular
+Expressions", the standard algorithm is an "NFA algorithm". It conducts a
+depth-first search of the pattern tree. That is, it proceeds along a single
+path through the tree, checking that the subject matches what is required. When
+there is a mismatch, the algorithm tries any alternatives at the current point,
+and if they all fail, it backs up to the previous branch point in the tree, and
+tries the next alternative branch at that level. This often involves backing up
+(moving to the left) in the subject string as well. The order in which
+repetition branches are tried is controlled by the greedy or ungreedy nature of
+the quantifier.
+</P>
+<P>
+If a leaf node is reached, a matching string has been found, and at that point
+the algorithm stops. Thus, if there is more than one possible match, this
+algorithm returns the first one that it finds. Whether this is the shortest,
+the longest, or some intermediate length depends on the way the greedy and
+ungreedy repetition quantifiers are specified in the pattern.
+</P>
+<P>
+Because it ends up with a single path through the tree, it is relatively
+straightforward for this algorithm to keep track of the substrings that are
+matched by portions of the pattern in parentheses. This provides support for
+capturing parentheses and back references.
+</P>
+<br><a name="SEC4" href="#TOC1">THE ALTERNATIVE MATCHING ALGORITHM</a><br>
+<P>
+This algorithm conducts a breadth-first search of the tree. Starting from the
+first matching point in the subject, it scans the subject string from left to
+right, once, character by character, and as it does this, it remembers all the
+paths through the tree that represent valid matches. In Friedl's terminology,
+this is a kind of "DFA algorithm", though it is not implemented as a
+traditional finite state machine (it keeps multiple states active
+simultaneously).
+</P>
+<P>
+Although the general principle of this matching algorithm is that it scans the
+subject string only once, without backtracking, there is one exception: when a
+lookaround assertion is encountered, the characters following or preceding the
+current point have to be independently inspected.
+</P>
+<P>
+The scan continues until either the end of the subject is reached, or there are
+no more unterminated paths. At this point, terminated paths represent the
+different matching possibilities (if there are none, the match has failed).
+Thus, if there is more than one possible match, this algorithm finds all of
+them, and in particular, it finds the longest. The matches are returned in
+decreasing order of length. There is an option to stop the algorithm after the
+first match (which is necessarily the shortest) is found.
+</P>
+<P>
+Note that all the matches that are found start at the same point in the
+subject. If the pattern
+<pre>
+  cat(er(pillar)?)?
+</pre>
+is matched against the string "the caterpillar catchment", the result will be
+the three strings "caterpillar", "cater", and "cat" that start at the fifth
+character of the subject. The algorithm does not automatically move on to find
+matches that start at later positions.
+</P>
+<P>
+PCRE's "auto-possessification" optimization usually applies to character
+repeats at the end of a pattern (as well as internally). For example, the
+pattern "a\d+" is compiled as if it were "a\d++" because there is no point
+even considering the possibility of backtracking into the repeated digits. For
+DFA matching, this means that only one possible match is found. If you really
+do want multiple matches in such cases, either use an ungreedy repeat
+("a\d+?") or set the PCRE_NO_AUTO_POSSESS option when compiling.
+</P>
+<P>
+There are a number of features of PCRE regular expressions that are not
+supported by the alternative matching algorithm. They are as follows:
+</P>
+<P>
+1. Because the algorithm finds all possible matches, the greedy or ungreedy
+nature of repetition quantifiers is not relevant. Greedy and ungreedy
+quantifiers are treated in exactly the same way. However, possessive
+quantifiers can make a difference when what follows could also match what is
+quantified, for example in a pattern like this:
+<pre>
+  ^a++\w!
+</pre>
+This pattern matches "aaab!" but not "aaa!", which would be matched by a
+non-possessive quantifier. Similarly, if an atomic group is present, it is
+matched as if it were a standalone pattern at the current point, and the
+longest match is then "locked in" for the rest of the overall pattern.
+</P>
+<P>
+2. When dealing with multiple paths through the tree simultaneously, it is not
+straightforward to keep track of captured substrings for the different matching
+possibilities, and PCRE's implementation of this algorithm does not attempt to
+do this. This means that no captured substrings are available.
+</P>
+<P>
+3. Because no substrings are captured, back references within the pattern are
+not supported, and cause errors if encountered.
+</P>
+<P>
+4. For the same reason, conditional expressions that use a backreference as the
+condition or test for a specific group recursion are not supported.
+</P>
+<P>
+5. Because many paths through the tree may be active, the \K escape sequence,
+which resets the start of the match when encountered (but may be on some paths
+and not on others), is not supported. It causes an error if encountered.
+</P>
+<P>
+6. Callouts are supported, but the value of the <i>capture_top</i> field is
+always 1, and the value of the <i>capture_last</i> field is always -1.
+</P>
+<P>
+7. The \C escape sequence, which (in the standard algorithm) always matches a
+single data unit, even in UTF-8, UTF-16 or UTF-32 modes, is not supported in
+these modes, because the alternative algorithm moves through the subject string
+one character (not data unit) at a time, for all active paths through the tree.
+</P>
+<P>
+8. Except for (*FAIL), the backtracking control verbs such as (*PRUNE) are not
+supported. (*FAIL) is supported, and behaves like a failing negative assertion.
+</P>
+<br><a name="SEC5" href="#TOC1">ADVANTAGES OF THE ALTERNATIVE ALGORITHM</a><br>
+<P>
+Using the alternative matching algorithm provides the following advantages:
+</P>
+<P>
+1. All possible matches (at a single point in the subject) are automatically
+found, and in particular, the longest match is found. To find more than one
+match using the standard algorithm, you have to do kludgy things with
+callouts.
+</P>
+<P>
+2. Because the alternative algorithm scans the subject string just once, and
+never needs to backtrack (except for lookbehinds), it is possible to pass very
+long subject strings to the matching function in several pieces, checking for
+partial matching each time. Although it is possible to do multi-segment
+matching using the standard algorithm by retaining partially matched
+substrings, it is more complicated. The
+<a href="pcrepartial.html"><b>pcrepartial</b></a>
+documentation gives details of partial matching and discusses multi-segment
+matching.
+</P>
+<br><a name="SEC6" href="#TOC1">DISADVANTAGES OF THE ALTERNATIVE ALGORITHM</a><br>
+<P>
+The alternative algorithm suffers from a number of disadvantages:
+</P>
+<P>
+1. It is substantially slower than the standard algorithm. This is partly
+because it has to search for all possible matches, but is also because it is
+less susceptible to optimization.
+</P>
+<P>
+2. Capturing parentheses and back references are not supported.
+</P>
+<P>
+3. Although atomic groups are supported, their use does not provide the
+performance advantage that it does for the standard algorithm.
+</P>
+<br><a name="SEC7" href="#TOC1">AUTHOR</a><br>
+<P>
+Philip Hazel
+<br>
+University Computing Service
+<br>
+Cambridge CB2 3QH, England.
+<br>
+</P>
+<br><a name="SEC8" href="#TOC1">REVISION</a><br>
+<P>
+Last updated: 12 November 2013
+<br>
+Copyright &copy; 1997-2012 University of Cambridge.
+<br>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcrepartial.html b/libs/Pcre16/docs/doc/html/pcrepartial.html
new file mode 100644
index 0000000000..4faeafcb68
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcrepartial.html
@@ -0,0 +1,509 @@
+<html>
+<head>
+<title>pcrepartial specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcrepartial man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<ul>
+<li><a name="TOC1" href="#SEC1">PARTIAL MATCHING IN PCRE</a>
+<li><a name="TOC2" href="#SEC2">PARTIAL MATCHING USING pcre_exec() OR pcre[16|32]_exec()</a>
+<li><a name="TOC3" href="#SEC3">PARTIAL MATCHING USING pcre_dfa_exec() OR pcre[16|32]_dfa_exec()</a>
+<li><a name="TOC4" href="#SEC4">PARTIAL MATCHING AND WORD BOUNDARIES</a>
+<li><a name="TOC5" href="#SEC5">FORMERLY RESTRICTED PATTERNS</a>
+<li><a name="TOC6" href="#SEC6">EXAMPLE OF PARTIAL MATCHING USING PCRETEST</a>
+<li><a name="TOC7" href="#SEC7">MULTI-SEGMENT MATCHING WITH pcre_dfa_exec() OR pcre[16|32]_dfa_exec()</a>
+<li><a name="TOC8" href="#SEC8">MULTI-SEGMENT MATCHING WITH pcre_exec() OR pcre[16|32]_exec()</a>
+<li><a name="TOC9" href="#SEC9">ISSUES WITH MULTI-SEGMENT MATCHING</a>
+<li><a name="TOC10" href="#SEC10">AUTHOR</a>
+<li><a name="TOC11" href="#SEC11">REVISION</a>
+</ul>
+<br><a name="SEC1" href="#TOC1">PARTIAL MATCHING IN PCRE</a><br>
+<P>
+In normal use of PCRE, if the subject string that is passed to a matching
+function matches as far as it goes, but is too short to match the entire
+pattern, PCRE_ERROR_NOMATCH is returned. There are circumstances where it might
+be helpful to distinguish this case from other cases in which there is no
+match.
+</P>
+<P>
+Consider, for example, an application where a human is required to type in data
+for a field with specific formatting requirements. An example might be a date
+in the form <i>ddmmmyy</i>, defined by this pattern:
+<pre>
+  ^\d?\d(jan|feb|mar|apr|may|jun|jul|aug|sep|oct|nov|dec)\d\d$
+</pre>
+If the application sees the user's keystrokes one by one, and can check that
+what has been typed so far is potentially valid, it is able to raise an error
+as soon as a mistake is made, by beeping and not reflecting the character that
+has been typed, for example. This immediate feedback is likely to be a better
+user interface than a check that is delayed until the entire string has been
+entered. Partial matching can also be useful when the subject string is very
+long and is not all available at once.
+</P>
+<P>
+PCRE supports partial matching by means of the PCRE_PARTIAL_SOFT and
+PCRE_PARTIAL_HARD options, which can be set when calling any of the matching
+functions. For backwards compatibility, PCRE_PARTIAL is a synonym for
+PCRE_PARTIAL_SOFT. The essential difference between the two options is whether
+or not a partial match is preferred to an alternative complete match, though
+the details differ between the two types of matching function. If both options
+are set, PCRE_PARTIAL_HARD takes precedence.
+</P>
+<P>
+If you want to use partial matching with just-in-time optimized code, you must
+call <b>pcre_study()</b>, <b>pcre16_study()</b> or  <b>pcre32_study()</b> with one
+or both of these options:
+<pre>
+  PCRE_STUDY_JIT_PARTIAL_SOFT_COMPILE
+  PCRE_STUDY_JIT_PARTIAL_HARD_COMPILE
+</pre>
+PCRE_STUDY_JIT_COMPILE should also be set if you are going to run non-partial
+matches on the same pattern. If the appropriate JIT study mode has not been set
+for a match, the interpretive matching code is used.
+</P>
+<P>
+Setting a partial matching option disables two of PCRE's standard
+optimizations. PCRE remembers the last literal data unit in a pattern, and
+abandons matching immediately if it is not present in the subject string. This
+optimization cannot be used for a subject string that might match only
+partially. If the pattern was studied, PCRE knows the minimum length of a
+matching string, and does not bother to run the matching function on shorter
+strings. This optimization is also disabled for partial matching.
+</P>
+<br><a name="SEC2" href="#TOC1">PARTIAL MATCHING USING pcre_exec() OR pcre[16|32]_exec()</a><br>
+<P>
+A partial match occurs during a call to <b>pcre_exec()</b> or
+<b>pcre[16|32]_exec()</b> when the end of the subject string is reached
+successfully, but matching cannot continue because more characters are needed.
+However, at least one character in the subject must have been inspected. This
+character need not form part of the final matched string; lookbehind assertions
+and the \K escape sequence provide ways of inspecting characters before the
+start of a matched substring. The requirement for inspecting at least one
+character exists because an empty string can always be matched; without such a
+restriction there would always be a partial match of an empty string at the end
+of the subject.
+</P>
+<P>
+If there are at least two slots in the offsets vector when a partial match is
+returned, the first slot is set to the offset of the earliest character that
+was inspected. For convenience, the second offset points to the end of the
+subject so that a substring can easily be identified. If there are at least
+three slots in the offsets vector, the third slot is set to the offset of the
+character where matching started.
+</P>
+<P>
+For the majority of patterns, the contents of the first and third slots will be
+the same. However, for patterns that contain lookbehind assertions, or begin
+with \b or \B, characters before the one where matching started may have been
+inspected while carrying out the match. For example, consider this pattern:
+<pre>
+  /(?&#60;=abc)123/
+</pre>
+This pattern matches "123", but only if it is preceded by "abc". If the subject
+string is "xyzabc12", the first two offsets after a partial match are for the
+substring "abc12", because all these characters were inspected. However, the
+third offset is set to 6, because that is the offset where matching began.
+</P>
+<P>
+What happens when a partial match is identified depends on which of the two
+partial matching options are set.
+</P>
+<br><b>
+PCRE_PARTIAL_SOFT WITH pcre_exec() OR pcre[16|32]_exec()
+</b><br>
+<P>
+If PCRE_PARTIAL_SOFT is set when <b>pcre_exec()</b> or <b>pcre[16|32]_exec()</b>
+identifies a partial match, the partial match is remembered, but matching
+continues as normal, and other alternatives in the pattern are tried. If no
+complete match can be found, PCRE_ERROR_PARTIAL is returned instead of
+PCRE_ERROR_NOMATCH.
+</P>
+<P>
+This option is "soft" because it prefers a complete match over a partial match.
+All the various matching items in a pattern behave as if the subject string is
+potentially complete. For example, \z, \Z, and $ match at the end of the
+subject, as normal, and for \b and \B the end of the subject is treated as a
+non-alphanumeric.
+</P>
+<P>
+If there is more than one partial match, the first one that was found provides
+the data that is returned. Consider this pattern:
+<pre>
+  /123\w+X|dogY/
+</pre>
+If this is matched against the subject string "abc123dog", both
+alternatives fail to match, but the end of the subject is reached during
+matching, so PCRE_ERROR_PARTIAL is returned. The offsets are set to 3 and 9,
+identifying "123dog" as the first partial match that was found. (In this
+example, there are two partial matches, because "dog" on its own partially
+matches the second alternative.)
+</P>
+<br><b>
+PCRE_PARTIAL_HARD WITH pcre_exec() OR pcre[16|32]_exec()
+</b><br>
+<P>
+If PCRE_PARTIAL_HARD is set for <b>pcre_exec()</b> or <b>pcre[16|32]_exec()</b>,
+PCRE_ERROR_PARTIAL is returned as soon as a partial match is found, without
+continuing to search for possible complete matches. This option is "hard"
+because it prefers an earlier partial match over a later complete match. For
+this reason, the assumption is made that the end of the supplied subject string
+may not be the true end of the available data, and so, if \z, \Z, \b, \B,
+or $ are encountered at the end of the subject, the result is
+PCRE_ERROR_PARTIAL, provided that at least one character in the subject has
+been inspected.
+</P>
+<P>
+Setting PCRE_PARTIAL_HARD also affects the way UTF-8 and UTF-16
+subject strings are checked for validity. Normally, an invalid sequence
+causes the error PCRE_ERROR_BADUTF8 or PCRE_ERROR_BADUTF16. However, in the
+special case of a truncated character at the end of the subject,
+PCRE_ERROR_SHORTUTF8 or PCRE_ERROR_SHORTUTF16 is returned when
+PCRE_PARTIAL_HARD is set.
+</P>
+<br><b>
+Comparing hard and soft partial matching
+</b><br>
+<P>
+The difference between the two partial matching options can be illustrated by a
+pattern such as:
+<pre>
+  /dog(sbody)?/
+</pre>
+This matches either "dog" or "dogsbody", greedily (that is, it prefers the
+longer string if possible). If it is matched against the string "dog" with
+PCRE_PARTIAL_SOFT, it yields a complete match for "dog". However, if
+PCRE_PARTIAL_HARD is set, the result is PCRE_ERROR_PARTIAL. On the other hand,
+if the pattern is made ungreedy the result is different:
+<pre>
+  /dog(sbody)??/
+</pre>
+In this case the result is always a complete match because that is found first,
+and matching never continues after finding a complete match. It might be easier
+to follow this explanation by thinking of the two patterns like this:
+<pre>
+  /dog(sbody)?/    is the same as  /dogsbody|dog/
+  /dog(sbody)??/   is the same as  /dog|dogsbody/
+</pre>
+The second pattern will never match "dogsbody", because it will always find the
+shorter match first.
+</P>
+<br><a name="SEC3" href="#TOC1">PARTIAL MATCHING USING pcre_dfa_exec() OR pcre[16|32]_dfa_exec()</a><br>
+<P>
+The DFA functions move along the subject string character by character, without
+backtracking, searching for all possible matches simultaneously. If the end of
+the subject is reached before the end of the pattern, there is the possibility
+of a partial match, again provided that at least one character has been
+inspected.
+</P>
+<P>
+When PCRE_PARTIAL_SOFT is set, PCRE_ERROR_PARTIAL is returned only if there
+have been no complete matches. Otherwise, the complete matches are returned.
+However, if PCRE_PARTIAL_HARD is set, a partial match takes precedence over any
+complete matches. The portion of the string that was inspected when the longest
+partial match was found is set as the first matching string, provided there are
+at least two slots in the offsets vector.
+</P>
+<P>
+Because the DFA functions always search for all possible matches, and there is
+no difference between greedy and ungreedy repetition, their behaviour is
+different from the standard functions when PCRE_PARTIAL_HARD is set. Consider
+the string "dog" matched against the ungreedy pattern shown above:
+<pre>
+  /dog(sbody)??/
+</pre>
+Whereas the standard functions stop as soon as they find the complete match for
+"dog", the DFA functions also find the partial match for "dogsbody", and so
+return that when PCRE_PARTIAL_HARD is set.
+</P>
+<br><a name="SEC4" href="#TOC1">PARTIAL MATCHING AND WORD BOUNDARIES</a><br>
+<P>
+If a pattern ends with one of sequences \b or \B, which test for word
+boundaries, partial matching with PCRE_PARTIAL_SOFT can give counter-intuitive
+results. Consider this pattern:
+<pre>
+  /\bcat\b/
+</pre>
+This matches "cat", provided there is a word boundary at either end. If the
+subject string is "the cat", the comparison of the final "t" with a following
+character cannot take place, so a partial match is found. However, normal
+matching carries on, and \b matches at the end of the subject when the last
+character is a letter, so a complete match is found. The result, therefore, is
+<i>not</i> PCRE_ERROR_PARTIAL. Using PCRE_PARTIAL_HARD in this case does yield
+PCRE_ERROR_PARTIAL, because then the partial match takes precedence.
+</P>
+<br><a name="SEC5" href="#TOC1">FORMERLY RESTRICTED PATTERNS</a><br>
+<P>
+For releases of PCRE prior to 8.00, because of the way certain internal
+optimizations were implemented in the <b>pcre_exec()</b> function, the
+PCRE_PARTIAL option (predecessor of PCRE_PARTIAL_SOFT) could not be used with
+all patterns. From release 8.00 onwards, the restrictions no longer apply, and
+partial matching with can be requested for any pattern.
+</P>
+<P>
+Items that were formerly restricted were repeated single characters and
+repeated metasequences. If PCRE_PARTIAL was set for a pattern that did not
+conform to the restrictions, <b>pcre_exec()</b> returned the error code
+PCRE_ERROR_BADPARTIAL (-13). This error code is no longer in use. The
+PCRE_INFO_OKPARTIAL call to <b>pcre_fullinfo()</b> to find out if a compiled
+pattern can be used for partial matching now always returns 1.
+</P>
+<br><a name="SEC6" href="#TOC1">EXAMPLE OF PARTIAL MATCHING USING PCRETEST</a><br>
+<P>
+If the escape sequence \P is present in a <b>pcretest</b> data line, the
+PCRE_PARTIAL_SOFT option is used for the match. Here is a run of <b>pcretest</b>
+that uses the date example quoted above:
+<pre>
+    re&#62; /^\d?\d(jan|feb|mar|apr|may|jun|jul|aug|sep|oct|nov|dec)\d\d$/
+  data&#62; 25jun04\P
+   0: 25jun04
+   1: jun
+  data&#62; 25dec3\P
+  Partial match: 23dec3
+  data&#62; 3ju\P
+  Partial match: 3ju
+  data&#62; 3juj\P
+  No match
+  data&#62; j\P
+  No match
+</pre>
+The first data string is matched completely, so <b>pcretest</b> shows the
+matched substrings. The remaining four strings do not match the complete
+pattern, but the first two are partial matches. Similar output is obtained
+if DFA matching is used.
+</P>
+<P>
+If the escape sequence \P is present more than once in a <b>pcretest</b> data
+line, the PCRE_PARTIAL_HARD option is set for the match.
+</P>
+<br><a name="SEC7" href="#TOC1">MULTI-SEGMENT MATCHING WITH pcre_dfa_exec() OR pcre[16|32]_dfa_exec()</a><br>
+<P>
+When a partial match has been found using a DFA matching function, it is
+possible to continue the match by providing additional subject data and calling
+the function again with the same compiled regular expression, this time setting
+the PCRE_DFA_RESTART option. You must pass the same working space as before,
+because this is where details of the previous partial match are stored. Here is
+an example using <b>pcretest</b>, using the \R escape sequence to set the
+PCRE_DFA_RESTART option (\D specifies the use of the DFA matching function):
+<pre>
+    re&#62; /^\d?\d(jan|feb|mar|apr|may|jun|jul|aug|sep|oct|nov|dec)\d\d$/
+  data&#62; 23ja\P\D
+  Partial match: 23ja
+  data&#62; n05\R\D
+   0: n05
+</pre>
+The first call has "23ja" as the subject, and requests partial matching; the
+second call has "n05" as the subject for the continued (restarted) match.
+Notice that when the match is complete, only the last part is shown; PCRE does
+not retain the previously partially-matched string. It is up to the calling
+program to do that if it needs to.
+</P>
+<P>
+That means that, for an unanchored pattern, if a continued match fails, it is
+not possible to try again at a new starting point. All this facility is capable
+of doing is continuing with the previous match attempt. In the previous
+example, if the second set of data is "ug23" the result is no match, even
+though there would be a match for "aug23" if the entire string were given at
+once. Depending on the application, this may or may not be what you want.
+The only way to allow for starting again at the next character is to retain the
+matched part of the subject and try a new complete match.
+</P>
+<P>
+You can set the PCRE_PARTIAL_SOFT or PCRE_PARTIAL_HARD options with
+PCRE_DFA_RESTART to continue partial matching over multiple segments. This
+facility can be used to pass very long subject strings to the DFA matching
+functions.
+</P>
+<br><a name="SEC8" href="#TOC1">MULTI-SEGMENT MATCHING WITH pcre_exec() OR pcre[16|32]_exec()</a><br>
+<P>
+From release 8.00, the standard matching functions can also be used to do
+multi-segment matching. Unlike the DFA functions, it is not possible to
+restart the previous match with a new segment of data. Instead, new data must
+be added to the previous subject string, and the entire match re-run, starting
+from the point where the partial match occurred. Earlier data can be discarded.
+</P>
+<P>
+It is best to use PCRE_PARTIAL_HARD in this situation, because it does not
+treat the end of a segment as the end of the subject when matching \z, \Z,
+\b, \B, and $. Consider an unanchored pattern that matches dates:
+<pre>
+    re&#62; /\d?\d(jan|feb|mar|apr|may|jun|jul|aug|sep|oct|nov|dec)\d\d/
+  data&#62; The date is 23ja\P\P
+  Partial match: 23ja
+</pre>
+At this stage, an application could discard the text preceding "23ja", add on
+text from the next segment, and call the matching function again. Unlike the
+DFA matching functions, the entire matching string must always be available,
+and the complete matching process occurs for each call, so more memory and more
+processing time is needed.
+</P>
+<P>
+<b>Note:</b> If the pattern contains lookbehind assertions, or \K, or starts
+with \b or \B, the string that is returned for a partial match includes
+characters that precede the start of what would be returned for a complete
+match, because it contains all the characters that were inspected during the
+partial match.
+</P>
+<br><a name="SEC9" href="#TOC1">ISSUES WITH MULTI-SEGMENT MATCHING</a><br>
+<P>
+Certain types of pattern may give problems with multi-segment matching,
+whichever matching function is used.
+</P>
+<P>
+1. If the pattern contains a test for the beginning of a line, you need to pass
+the PCRE_NOTBOL option when the subject string for any call does start at the
+beginning of a line. There is also a PCRE_NOTEOL option, but in practice when
+doing multi-segment matching you should be using PCRE_PARTIAL_HARD, which
+includes the effect of PCRE_NOTEOL.
+</P>
+<P>
+2. Lookbehind assertions that have already been obeyed are catered for in the
+offsets that are returned for a partial match. However a lookbehind assertion
+later in the pattern could require even earlier characters to be inspected. You
+can handle this case by using the PCRE_INFO_MAXLOOKBEHIND option of the
+<b>pcre_fullinfo()</b> or <b>pcre[16|32]_fullinfo()</b> functions to obtain the
+length of the longest lookbehind in the pattern. This length is given in
+characters, not bytes. If you always retain at least that many characters
+before the partially matched string, all should be well. (Of course, near the
+start of the subject, fewer characters may be present; in that case all
+characters should be retained.)
+</P>
+<P>
+From release 8.33, there is a more accurate way of deciding which characters to
+retain. Instead of subtracting the length of the longest lookbehind from the
+earliest inspected character (<i>offsets[0]</i>), the match start position
+(<i>offsets[2]</i>) should be used, and the next match attempt started at the
+<i>offsets[2]</i> character by setting the <i>startoffset</i> argument of
+<b>pcre_exec()</b> or <b>pcre_dfa_exec()</b>.
+</P>
+<P>
+For example, if the pattern "(?&#60;=123)abc" is partially
+matched against the string "xx123a", the three offset values returned are 2, 6,
+and 5. This indicates that the matching process that gave a partial match
+started at offset 5, but the characters "123a" were all inspected. The maximum
+lookbehind for that pattern is 3, so taking that away from 5 shows that we need
+only keep "123a", and the next match attempt can be started at offset 3 (that
+is, at "a") when further characters have been added. When the match start is
+not the earliest inspected character, <b>pcretest</b> shows it explicitly:
+<pre>
+    re&#62; "(?&#60;=123)abc"
+  data&#62; xx123a\P\P
+  Partial match at offset 5: 123a
+</PRE>
+</P>
+<P>
+3. Because a partial match must always contain at least one character, what
+might be considered a partial match of an empty string actually gives a "no
+match" result. For example:
+<pre>
+    re&#62; /c(?&#60;=abc)x/
+  data&#62; ab\P
+  No match
+</pre>
+If the next segment begins "cx", a match should be found, but this will only
+happen if characters from the previous segment are retained. For this reason, a
+"no match" result should be interpreted as "partial match of an empty string"
+when the pattern contains lookbehinds.
+</P>
+<P>
+4. Matching a subject string that is split into multiple segments may not
+always produce exactly the same result as matching over one single long string,
+especially when PCRE_PARTIAL_SOFT is used. The section "Partial Matching and
+Word Boundaries" above describes an issue that arises if the pattern ends with
+\b or \B. Another kind of difference may occur when there are multiple
+matching possibilities, because (for PCRE_PARTIAL_SOFT) a partial match result
+is given only when there are no completed matches. This means that as soon as
+the shortest match has been found, continuation to a new subject segment is no
+longer possible. Consider again this <b>pcretest</b> example:
+<pre>
+    re&#62; /dog(sbody)?/
+  data&#62; dogsb\P
+   0: dog
+  data&#62; do\P\D
+  Partial match: do
+  data&#62; gsb\R\P\D
+   0: g
+  data&#62; dogsbody\D
+   0: dogsbody
+   1: dog
+</pre>
+The first data line passes the string "dogsb" to a standard matching function,
+setting the PCRE_PARTIAL_SOFT option. Although the string is a partial match
+for "dogsbody", the result is not PCRE_ERROR_PARTIAL, because the shorter
+string "dog" is a complete match. Similarly, when the subject is presented to
+a DFA matching function in several parts ("do" and "gsb" being the first two)
+the match stops when "dog" has been found, and it is not possible to continue.
+On the other hand, if "dogsbody" is presented as a single string, a DFA
+matching function finds both matches.
+</P>
+<P>
+Because of these problems, it is best to use PCRE_PARTIAL_HARD when matching
+multi-segment data. The example above then behaves differently:
+<pre>
+    re&#62; /dog(sbody)?/
+  data&#62; dogsb\P\P
+  Partial match: dogsb
+  data&#62; do\P\D
+  Partial match: do
+  data&#62; gsb\R\P\P\D
+  Partial match: gsb
+</pre>
+5. Patterns that contain alternatives at the top level which do not all start
+with the same pattern item may not work as expected when PCRE_DFA_RESTART is
+used. For example, consider this pattern:
+<pre>
+  1234|3789
+</pre>
+If the first part of the subject is "ABC123", a partial match of the first
+alternative is found at offset 3. There is no partial match for the second
+alternative, because such a match does not start at the same point in the
+subject string. Attempting to continue with the string "7890" does not yield a
+match because only those alternatives that match at one point in the subject
+are remembered. The problem arises because the start of the second alternative
+matches within the first alternative. There is no problem with anchored
+patterns or patterns such as:
+<pre>
+  1234|ABCD
+</pre>
+where no string can be a partial match for both alternatives. This is not a
+problem if a standard matching function is used, because the entire match has
+to be rerun each time:
+<pre>
+    re&#62; /1234|3789/
+  data&#62; ABC123\P\P
+  Partial match: 123
+  data&#62; 1237890
+   0: 3789
+</pre>
+Of course, instead of using PCRE_DFA_RESTART, the same technique of re-running
+the entire match can also be used with the DFA matching functions. Another
+possibility is to work with two buffers. If a partial match at offset <i>n</i>
+in the first buffer is followed by "no match" when PCRE_DFA_RESTART is used on
+the second buffer, you can then try a new match starting at offset <i>n+1</i> in
+the first buffer.
+</P>
+<br><a name="SEC10" href="#TOC1">AUTHOR</a><br>
+<P>
+Philip Hazel
+<br>
+University Computing Service
+<br>
+Cambridge CB2 3QH, England.
+<br>
+</P>
+<br><a name="SEC11" href="#TOC1">REVISION</a><br>
+<P>
+Last updated: 02 July 2013
+<br>
+Copyright &copy; 1997-2013 University of Cambridge.
+<br>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcrepattern.html b/libs/Pcre16/docs/doc/html/pcrepattern.html
new file mode 100644
index 0000000000..c06d1e03f1
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcrepattern.html
@@ -0,0 +1,3235 @@
+<html>
+<head>
+<title>pcrepattern specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcrepattern man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<ul>
+<li><a name="TOC1" href="#SEC1">PCRE REGULAR EXPRESSION DETAILS</a>
+<li><a name="TOC2" href="#SEC2">SPECIAL START-OF-PATTERN ITEMS</a>
+<li><a name="TOC3" href="#SEC3">EBCDIC CHARACTER CODES</a>
+<li><a name="TOC4" href="#SEC4">CHARACTERS AND METACHARACTERS</a>
+<li><a name="TOC5" href="#SEC5">BACKSLASH</a>
+<li><a name="TOC6" href="#SEC6">CIRCUMFLEX AND DOLLAR</a>
+<li><a name="TOC7" href="#SEC7">FULL STOP (PERIOD, DOT) AND \N</a>
+<li><a name="TOC8" href="#SEC8">MATCHING A SINGLE DATA UNIT</a>
+<li><a name="TOC9" href="#SEC9">SQUARE BRACKETS AND CHARACTER CLASSES</a>
+<li><a name="TOC10" href="#SEC10">POSIX CHARACTER CLASSES</a>
+<li><a name="TOC11" href="#SEC11">COMPATIBILITY FEATURE FOR WORD BOUNDARIES</a>
+<li><a name="TOC12" href="#SEC12">VERTICAL BAR</a>
+<li><a name="TOC13" href="#SEC13">INTERNAL OPTION SETTING</a>
+<li><a name="TOC14" href="#SEC14">SUBPATTERNS</a>
+<li><a name="TOC15" href="#SEC15">DUPLICATE SUBPATTERN NUMBERS</a>
+<li><a name="TOC16" href="#SEC16">NAMED SUBPATTERNS</a>
+<li><a name="TOC17" href="#SEC17">REPETITION</a>
+<li><a name="TOC18" href="#SEC18">ATOMIC GROUPING AND POSSESSIVE QUANTIFIERS</a>
+<li><a name="TOC19" href="#SEC19">BACK REFERENCES</a>
+<li><a name="TOC20" href="#SEC20">ASSERTIONS</a>
+<li><a name="TOC21" href="#SEC21">CONDITIONAL SUBPATTERNS</a>
+<li><a name="TOC22" href="#SEC22">COMMENTS</a>
+<li><a name="TOC23" href="#SEC23">RECURSIVE PATTERNS</a>
+<li><a name="TOC24" href="#SEC24">SUBPATTERNS AS SUBROUTINES</a>
+<li><a name="TOC25" href="#SEC25">ONIGURUMA SUBROUTINE SYNTAX</a>
+<li><a name="TOC26" href="#SEC26">CALLOUTS</a>
+<li><a name="TOC27" href="#SEC27">BACKTRACKING CONTROL</a>
+<li><a name="TOC28" href="#SEC28">SEE ALSO</a>
+<li><a name="TOC29" href="#SEC29">AUTHOR</a>
+<li><a name="TOC30" href="#SEC30">REVISION</a>
+</ul>
+<br><a name="SEC1" href="#TOC1">PCRE REGULAR EXPRESSION DETAILS</a><br>
+<P>
+The syntax and semantics of the regular expressions that are supported by PCRE
+are described in detail below. There is a quick-reference syntax summary in the
+<a href="pcresyntax.html"><b>pcresyntax</b></a>
+page. PCRE tries to match Perl syntax and semantics as closely as it can. PCRE
+also supports some alternative regular expression syntax (which does not
+conflict with the Perl syntax) in order to provide some compatibility with
+regular expressions in Python, .NET, and Oniguruma.
+</P>
+<P>
+Perl's regular expressions are described in its own documentation, and
+regular expressions in general are covered in a number of books, some of which
+have copious examples. Jeffrey Friedl's "Mastering Regular Expressions",
+published by O'Reilly, covers regular expressions in great detail. This
+description of PCRE's regular expressions is intended as reference material.
+</P>
+<P>
+This document discusses the patterns that are supported by PCRE when one its
+main matching functions, <b>pcre_exec()</b> (8-bit) or <b>pcre[16|32]_exec()</b>
+(16- or 32-bit), is used. PCRE also has alternative matching functions,
+<b>pcre_dfa_exec()</b> and <b>pcre[16|32_dfa_exec()</b>, which match using a
+different algorithm that is not Perl-compatible. Some of the features discussed
+below are not available when DFA matching is used. The advantages and
+disadvantages of the alternative functions, and how they differ from the normal
+functions, are discussed in the
+<a href="pcrematching.html"><b>pcrematching</b></a>
+page.
+</P>
+<br><a name="SEC2" href="#TOC1">SPECIAL START-OF-PATTERN ITEMS</a><br>
+<P>
+A number of options that can be passed to <b>pcre_compile()</b> can also be set
+by special items at the start of a pattern. These are not Perl-compatible, but
+are provided to make these options accessible to pattern writers who are not
+able to change the program that processes the pattern. Any number of these
+items may appear, but they must all be together right at the start of the
+pattern string, and the letters must be in upper case.
+</P>
+<br><b>
+UTF support
+</b><br>
+<P>
+The original operation of PCRE was on strings of one-byte characters. However,
+there is now also support for UTF-8 strings in the original library, an
+extra library that supports 16-bit and UTF-16 character strings, and a
+third library that supports 32-bit and UTF-32 character strings. To use these
+features, PCRE must be built to include appropriate support. When using UTF
+strings you must either call the compiling function with the PCRE_UTF8,
+PCRE_UTF16, or PCRE_UTF32 option, or the pattern must start with one of
+these special sequences:
+<pre>
+  (*UTF8)
+  (*UTF16)
+  (*UTF32)
+  (*UTF)
+</pre>
+(*UTF) is a generic sequence that can be used with any of the libraries.
+Starting a pattern with such a sequence is equivalent to setting the relevant
+option. How setting a UTF mode affects pattern matching is mentioned in several
+places below. There is also a summary of features in the
+<a href="pcreunicode.html"><b>pcreunicode</b></a>
+page.
+</P>
+<P>
+Some applications that allow their users to supply patterns may wish to
+restrict them to non-UTF data for security reasons. If the PCRE_NEVER_UTF
+option is set at compile time, (*UTF) etc. are not allowed, and their
+appearance causes an error.
+</P>
+<br><b>
+Unicode property support
+</b><br>
+<P>
+Another special sequence that may appear at the start of a pattern is (*UCP).
+This has the same effect as setting the PCRE_UCP option: it causes sequences
+such as \d and \w to use Unicode properties to determine character types,
+instead of recognizing only characters with codes less than 128 via a lookup
+table.
+</P>
+<br><b>
+Disabling auto-possessification
+</b><br>
+<P>
+If a pattern starts with (*NO_AUTO_POSSESS), it has the same effect as setting
+the PCRE_NO_AUTO_POSSESS option at compile time. This stops PCRE from making
+quantifiers possessive when what follows cannot match the repeated item. For
+example, by default a+b is treated as a++b. For more details, see the
+<a href="pcreapi.html"><b>pcreapi</b></a>
+documentation.
+</P>
+<br><b>
+Disabling start-up optimizations
+</b><br>
+<P>
+If a pattern starts with (*NO_START_OPT), it has the same effect as setting the
+PCRE_NO_START_OPTIMIZE option either at compile or matching time. This disables
+several optimizations for quickly reaching "no match" results. For more
+details, see the
+<a href="pcreapi.html"><b>pcreapi</b></a>
+documentation.
+<a name="newlines"></a></P>
+<br><b>
+Newline conventions
+</b><br>
+<P>
+PCRE supports five different conventions for indicating line breaks in
+strings: a single CR (carriage return) character, a single LF (linefeed)
+character, the two-character sequence CRLF, any of the three preceding, or any
+Unicode newline sequence. The
+<a href="pcreapi.html"><b>pcreapi</b></a>
+page has
+<a href="pcreapi.html#newlines">further discussion</a>
+about newlines, and shows how to set the newline convention in the
+<i>options</i> arguments for the compiling and matching functions.
+</P>
+<P>
+It is also possible to specify a newline convention by starting a pattern
+string with one of the following five sequences:
+<pre>
+  (*CR)        carriage return
+  (*LF)        linefeed
+  (*CRLF)      carriage return, followed by linefeed
+  (*ANYCRLF)   any of the three above
+  (*ANY)       all Unicode newline sequences
+</pre>
+These override the default and the options given to the compiling function. For
+example, on a Unix system where LF is the default newline sequence, the pattern
+<pre>
+  (*CR)a.b
+</pre>
+changes the convention to CR. That pattern matches "a\nb" because LF is no
+longer a newline. If more than one of these settings is present, the last one
+is used.
+</P>
+<P>
+The newline convention affects where the circumflex and dollar assertions are
+true. It also affects the interpretation of the dot metacharacter when
+PCRE_DOTALL is not set, and the behaviour of \N. However, it does not affect
+what the \R escape sequence matches. By default, this is any Unicode newline
+sequence, for Perl compatibility. However, this can be changed; see the
+description of \R in the section entitled
+<a href="#newlineseq">"Newline sequences"</a>
+below. A change of \R setting can be combined with a change of newline
+convention.
+</P>
+<br><b>
+Setting match and recursion limits
+</b><br>
+<P>
+The caller of <b>pcre_exec()</b> can set a limit on the number of times the
+internal <b>match()</b> function is called and on the maximum depth of
+recursive calls. These facilities are provided to catch runaway matches that
+are provoked by patterns with huge matching trees (a typical example is a
+pattern with nested unlimited repeats) and to avoid running out of system stack
+by too much recursion. When one of these limits is reached, <b>pcre_exec()</b>
+gives an error return. The limits can also be set by items at the start of the
+pattern of the form
+<pre>
+  (*LIMIT_MATCH=d)
+  (*LIMIT_RECURSION=d)
+</pre>
+where d is any number of decimal digits. However, the value of the setting must
+be less than the value set (or defaulted) by the caller of <b>pcre_exec()</b>
+for it to have any effect. In other words, the pattern writer can lower the
+limits set by the programmer, but not raise them. If there is more than one
+setting of one of these limits, the lower value is used.
+</P>
+<br><a name="SEC3" href="#TOC1">EBCDIC CHARACTER CODES</a><br>
+<P>
+PCRE can be compiled to run in an environment that uses EBCDIC as its character
+code rather than ASCII or Unicode (typically a mainframe system). In the
+sections below, character code values are ASCII or Unicode; in an EBCDIC
+environment these characters may have different code values, and there are no
+code points greater than 255.
+</P>
+<br><a name="SEC4" href="#TOC1">CHARACTERS AND METACHARACTERS</a><br>
+<P>
+A regular expression is a pattern that is matched against a subject string from
+left to right. Most characters stand for themselves in a pattern, and match the
+corresponding characters in the subject. As a trivial example, the pattern
+<pre>
+  The quick brown fox
+</pre>
+matches a portion of a subject string that is identical to itself. When
+caseless matching is specified (the PCRE_CASELESS option), letters are matched
+independently of case. In a UTF mode, PCRE always understands the concept of
+case for characters whose values are less than 128, so caseless matching is
+always possible. For characters with higher values, the concept of case is
+supported if PCRE is compiled with Unicode property support, but not otherwise.
+If you want to use caseless matching for characters 128 and above, you must
+ensure that PCRE is compiled with Unicode property support as well as with
+UTF support.
+</P>
+<P>
+The power of regular expressions comes from the ability to include alternatives
+and repetitions in the pattern. These are encoded in the pattern by the use of
+<i>metacharacters</i>, which do not stand for themselves but instead are
+interpreted in some special way.
+</P>
+<P>
+There are two different sets of metacharacters: those that are recognized
+anywhere in the pattern except within square brackets, and those that are
+recognized within square brackets. Outside square brackets, the metacharacters
+are as follows:
+<pre>
+  \      general escape character with several uses
+  ^      assert start of string (or line, in multiline mode)
+  $      assert end of string (or line, in multiline mode)
+  .      match any character except newline (by default)
+  [      start character class definition
+  |      start of alternative branch
+  (      start subpattern
+  )      end subpattern
+  ?      extends the meaning of (
+         also 0 or 1 quantifier
+         also quantifier minimizer
+  *      0 or more quantifier
+  +      1 or more quantifier
+         also "possessive quantifier"
+  {      start min/max quantifier
+</pre>
+Part of a pattern that is in square brackets is called a "character class". In
+a character class the only metacharacters are:
+<pre>
+  \      general escape character
+  ^      negate the class, but only if the first character
+  -      indicates character range
+  [      POSIX character class (only if followed by POSIX syntax)
+  ]      terminates the character class
+</pre>
+The following sections describe the use of each of the metacharacters.
+</P>
+<br><a name="SEC5" href="#TOC1">BACKSLASH</a><br>
+<P>
+The backslash character has several uses. Firstly, if it is followed by a
+character that is not a number or a letter, it takes away any special meaning
+that character may have. This use of backslash as an escape character applies
+both inside and outside character classes.
+</P>
+<P>
+For example, if you want to match a * character, you write \* in the pattern.
+This escaping action applies whether or not the following character would
+otherwise be interpreted as a metacharacter, so it is always safe to precede a
+non-alphanumeric with backslash to specify that it stands for itself. In
+particular, if you want to match a backslash, you write \\.
+</P>
+<P>
+In a UTF mode, only ASCII numbers and letters have any special meaning after a
+backslash. All other characters (in particular, those whose codepoints are
+greater than 127) are treated as literals.
+</P>
+<P>
+If a pattern is compiled with the PCRE_EXTENDED option, most white space in the
+pattern (other than in a character class), and characters between a # outside a
+character class and the next newline, inclusive, are ignored. An escaping
+backslash can be used to include a white space or # character as part of the
+pattern.
+</P>
+<P>
+If you want to remove the special meaning from a sequence of characters, you
+can do so by putting them between \Q and \E. This is different from Perl in
+that $ and @ are handled as literals in \Q...\E sequences in PCRE, whereas in
+Perl, $ and @ cause variable interpolation. Note the following examples:
+<pre>
+  Pattern            PCRE matches   Perl matches
+
+  \Qabc$xyz\E        abc$xyz        abc followed by the contents of $xyz
+  \Qabc\$xyz\E       abc\$xyz       abc\$xyz
+  \Qabc\E\$\Qxyz\E   abc$xyz        abc$xyz
+</pre>
+The \Q...\E sequence is recognized both inside and outside character classes.
+An isolated \E that is not preceded by \Q is ignored. If \Q is not followed
+by \E later in the pattern, the literal interpretation continues to the end of
+the pattern (that is, \E is assumed at the end). If the isolated \Q is inside
+a character class, this causes an error, because the character class is not
+terminated.
+<a name="digitsafterbackslash"></a></P>
+<br><b>
+Non-printing characters
+</b><br>
+<P>
+A second use of backslash provides a way of encoding non-printing characters
+in patterns in a visible manner. There is no restriction on the appearance of
+non-printing characters, apart from the binary zero that terminates a pattern,
+but when a pattern is being prepared by text editing, it is often easier to use
+one of the following escape sequences than the binary character it represents:
+<pre>
+  \a        alarm, that is, the BEL character (hex 07)
+  \cx       "control-x", where x is any ASCII character
+  \e        escape (hex 1B)
+  \f        form feed (hex 0C)
+  \n        linefeed (hex 0A)
+  \r        carriage return (hex 0D)
+  \t        tab (hex 09)
+  \0dd      character with octal code 0dd
+  \ddd      character with octal code ddd, or back reference
+  \o{ddd..} character with octal code ddd..
+  \xhh      character with hex code hh
+  \x{hhh..} character with hex code hhh.. (non-JavaScript mode)
+  \uhhhh    character with hex code hhhh (JavaScript mode only)
+</pre>
+The precise effect of \cx on ASCII characters is as follows: if x is a lower
+case letter, it is converted to upper case. Then bit 6 of the character (hex
+40) is inverted. Thus \cA to \cZ become hex 01 to hex 1A (A is 41, Z is 5A),
+but \c{ becomes hex 3B ({ is 7B), and \c; becomes hex 7B (; is 3B). If the
+data item (byte or 16-bit value) following \c has a value greater than 127, a
+compile-time error occurs. This locks out non-ASCII characters in all modes.
+</P>
+<P>
+The \c facility was designed for use with ASCII characters, but with the
+extension to Unicode it is even less useful than it once was. It is, however,
+recognized when PCRE is compiled in EBCDIC mode, where data items are always
+bytes. In this mode, all values are valid after \c. If the next character is a
+lower case letter, it is converted to upper case. Then the 0xc0 bits of the
+byte are inverted. Thus \cA becomes hex 01, as in ASCII (A is C1), but because
+the EBCDIC letters are disjoint, \cZ becomes hex 29 (Z is E9), and other
+characters also generate different values.
+</P>
+<P>
+After \0 up to two further octal digits are read. If there are fewer than two
+digits, just those that are present are used. Thus the sequence \0\x\07
+specifies two binary zeros followed by a BEL character (code value 7). Make
+sure you supply two digits after the initial zero if the pattern character that
+follows is itself an octal digit.
+</P>
+<P>
+The escape \o must be followed by a sequence of octal digits, enclosed in
+braces. An error occurs if this is not the case. This escape is a recent
+addition to Perl; it provides way of specifying character code points as octal
+numbers greater than 0777, and it also allows octal numbers and back references
+to be unambiguously specified.
+</P>
+<P>
+For greater clarity and unambiguity, it is best to avoid following \ by a
+digit greater than zero. Instead, use \o{} or \x{} to specify character
+numbers, and \g{} to specify back references. The following paragraphs
+describe the old, ambiguous syntax.
+</P>
+<P>
+The handling of a backslash followed by a digit other than 0 is complicated,
+and Perl has changed in recent releases, causing PCRE also to change. Outside a
+character class, PCRE reads the digit and any following digits as a decimal
+number. If the number is less than 8, or if there have been at least that many
+previous capturing left parentheses in the expression, the entire sequence is
+taken as a <i>back reference</i>. A description of how this works is given
+<a href="#backreferences">later,</a>
+following the discussion of
+<a href="#subpattern">parenthesized subpatterns.</a>
+</P>
+<P>
+Inside a character class, or if the decimal number following \ is greater than
+7 and there have not been that many capturing subpatterns, PCRE handles \8 and
+\9 as the literal characters "8" and "9", and otherwise re-reads up to three
+octal digits following the backslash, using them to generate a data character.
+Any subsequent digits stand for themselves. For example:
+<pre>
+  \040   is another way of writing an ASCII space
+  \40    is the same, provided there are fewer than 40 previous capturing subpatterns
+  \7     is always a back reference
+  \11    might be a back reference, or another way of writing a tab
+  \011   is always a tab
+  \0113  is a tab followed by the character "3"
+  \113   might be a back reference, otherwise the character with octal code 113
+  \377   might be a back reference, otherwise the value 255 (decimal)
+  \81    is either a back reference, or the two characters "8" and "1"
+</pre>
+Note that octal values of 100 or greater that are specified using this syntax
+must not be introduced by a leading zero, because no more than three octal
+digits are ever read.
+</P>
+<P>
+By default, after \x that is not followed by {, from zero to two hexadecimal
+digits are read (letters can be in upper or lower case). Any number of
+hexadecimal digits may appear between \x{ and }. If a character other than
+a hexadecimal digit appears between \x{ and }, or if there is no terminating
+}, an error occurs.
+</P>
+<P>
+If the PCRE_JAVASCRIPT_COMPAT option is set, the interpretation of \x is
+as just described only when it is followed by two hexadecimal digits.
+Otherwise, it matches a literal "x" character. In JavaScript mode, support for
+code points greater than 256 is provided by \u, which must be followed by
+four hexadecimal digits; otherwise it matches a literal "u" character.
+</P>
+<P>
+Characters whose value is less than 256 can be defined by either of the two
+syntaxes for \x (or by \u in JavaScript mode). There is no difference in the
+way they are handled. For example, \xdc is exactly the same as \x{dc} (or
+\u00dc in JavaScript mode).
+</P>
+<br><b>
+Constraints on character values
+</b><br>
+<P>
+Characters that are specified using octal or hexadecimal numbers are
+limited to certain values, as follows:
+<pre>
+  8-bit non-UTF mode    less than 0x100
+  8-bit UTF-8 mode      less than 0x10ffff and a valid codepoint
+  16-bit non-UTF mode   less than 0x10000
+  16-bit UTF-16 mode    less than 0x10ffff and a valid codepoint
+  32-bit non-UTF mode   less than 0x100000000
+  32-bit UTF-32 mode    less than 0x10ffff and a valid codepoint
+</pre>
+Invalid Unicode codepoints are the range 0xd800 to 0xdfff (the so-called
+"surrogate" codepoints), and 0xffef.
+</P>
+<br><b>
+Escape sequences in character classes
+</b><br>
+<P>
+All the sequences that define a single character value can be used both inside
+and outside character classes. In addition, inside a character class, \b is
+interpreted as the backspace character (hex 08).
+</P>
+<P>
+\N is not allowed in a character class. \B, \R, and \X are not special
+inside a character class. Like other unrecognized escape sequences, they are
+treated as the literal characters "B", "R", and "X" by default, but cause an
+error if the PCRE_EXTRA option is set. Outside a character class, these
+sequences have different meanings.
+</P>
+<br><b>
+Unsupported escape sequences
+</b><br>
+<P>
+In Perl, the sequences \l, \L, \u, and \U are recognized by its string
+handler and used to modify the case of following characters. By default, PCRE
+does not support these escape sequences. However, if the PCRE_JAVASCRIPT_COMPAT
+option is set, \U matches a "U" character, and \u can be used to define a
+character by code point, as described in the previous section.
+</P>
+<br><b>
+Absolute and relative back references
+</b><br>
+<P>
+The sequence \g followed by an unsigned or a negative number, optionally
+enclosed in braces, is an absolute or relative back reference. A named back
+reference can be coded as \g{name}. Back references are discussed
+<a href="#backreferences">later,</a>
+following the discussion of
+<a href="#subpattern">parenthesized subpatterns.</a>
+</P>
+<br><b>
+Absolute and relative subroutine calls
+</b><br>
+<P>
+For compatibility with Oniguruma, the non-Perl syntax \g followed by a name or
+a number enclosed either in angle brackets or single quotes, is an alternative
+syntax for referencing a subpattern as a "subroutine". Details are discussed
+<a href="#onigurumasubroutines">later.</a>
+Note that \g{...} (Perl syntax) and \g&#60;...&#62; (Oniguruma syntax) are <i>not</i>
+synonymous. The former is a back reference; the latter is a
+<a href="#subpatternsassubroutines">subroutine</a>
+call.
+<a name="genericchartypes"></a></P>
+<br><b>
+Generic character types
+</b><br>
+<P>
+Another use of backslash is for specifying generic character types:
+<pre>
+  \d     any decimal digit
+  \D     any character that is not a decimal digit
+  \h     any horizontal white space character
+  \H     any character that is not a horizontal white space character
+  \s     any white space character
+  \S     any character that is not a white space character
+  \v     any vertical white space character
+  \V     any character that is not a vertical white space character
+  \w     any "word" character
+  \W     any "non-word" character
+</pre>
+There is also the single sequence \N, which matches a non-newline character.
+This is the same as
+<a href="#fullstopdot">the "." metacharacter</a>
+when PCRE_DOTALL is not set. Perl also uses \N to match characters by name;
+PCRE does not support this.
+</P>
+<P>
+Each pair of lower and upper case escape sequences partitions the complete set
+of characters into two disjoint sets. Any given character matches one, and only
+one, of each pair. The sequences can appear both inside and outside character
+classes. They each match one character of the appropriate type. If the current
+matching point is at the end of the subject string, all of them fail, because
+there is no character to match.
+</P>
+<P>
+For compatibility with Perl, \s did not used to match the VT character (code
+11), which made it different from the the POSIX "space" class. However, Perl
+added VT at release 5.18, and PCRE followed suit at release 8.34. The default
+\s characters are now HT (9), LF (10), VT (11), FF (12), CR (13), and space
+(32), which are defined as white space in the "C" locale. This list may vary if
+locale-specific matching is taking place. For example, in some locales the
+"non-breaking space" character (\xA0) is recognized as white space, and in
+others the VT character is not.
+</P>
+<P>
+A "word" character is an underscore or any character that is a letter or digit.
+By default, the definition of letters and digits is controlled by PCRE's
+low-valued character tables, and may vary if locale-specific matching is taking
+place (see
+<a href="pcreapi.html#localesupport">"Locale support"</a>
+in the
+<a href="pcreapi.html"><b>pcreapi</b></a>
+page). For example, in a French locale such as "fr_FR" in Unix-like systems,
+or "french" in Windows, some character codes greater than 127 are used for
+accented letters, and these are then matched by \w. The use of locales with
+Unicode is discouraged.
+</P>
+<P>
+By default, characters whose code points are greater than 127 never match \d,
+\s, or \w, and always match \D, \S, and \W, although this may vary for
+characters in the range 128-255 when locale-specific matching is happening.
+These escape sequences retain their original meanings from before Unicode
+support was available, mainly for efficiency reasons. If PCRE is compiled with
+Unicode property support, and the PCRE_UCP option is set, the behaviour is
+changed so that Unicode properties are used to determine character types, as
+follows:
+<pre>
+  \d  any character that matches \p{Nd} (decimal digit)
+  \s  any character that matches \p{Z} or \h or \v
+  \w  any character that matches \p{L} or \p{N}, plus underscore
+</pre>
+The upper case escapes match the inverse sets of characters. Note that \d
+matches only decimal digits, whereas \w matches any Unicode digit, as well as
+any Unicode letter, and underscore. Note also that PCRE_UCP affects \b, and
+\B because they are defined in terms of \w and \W. Matching these sequences
+is noticeably slower when PCRE_UCP is set.
+</P>
+<P>
+The sequences \h, \H, \v, and \V are features that were added to Perl at
+release 5.10. In contrast to the other sequences, which match only ASCII
+characters by default, these always match certain high-valued code points,
+whether or not PCRE_UCP is set. The horizontal space characters are:
+<pre>
+  U+0009     Horizontal tab (HT)
+  U+0020     Space
+  U+00A0     Non-break space
+  U+1680     Ogham space mark
+  U+180E     Mongolian vowel separator
+  U+2000     En quad
+  U+2001     Em quad
+  U+2002     En space
+  U+2003     Em space
+  U+2004     Three-per-em space
+  U+2005     Four-per-em space
+  U+2006     Six-per-em space
+  U+2007     Figure space
+  U+2008     Punctuation space
+  U+2009     Thin space
+  U+200A     Hair space
+  U+202F     Narrow no-break space
+  U+205F     Medium mathematical space
+  U+3000     Ideographic space
+</pre>
+The vertical space characters are:
+<pre>
+  U+000A     Linefeed (LF)
+  U+000B     Vertical tab (VT)
+  U+000C     Form feed (FF)
+  U+000D     Carriage return (CR)
+  U+0085     Next line (NEL)
+  U+2028     Line separator
+  U+2029     Paragraph separator
+</pre>
+In 8-bit, non-UTF-8 mode, only the characters with codepoints less than 256 are
+relevant.
+<a name="newlineseq"></a></P>
+<br><b>
+Newline sequences
+</b><br>
+<P>
+Outside a character class, by default, the escape sequence \R matches any
+Unicode newline sequence. In 8-bit non-UTF-8 mode \R is equivalent to the
+following:
+<pre>
+  (?&#62;\r\n|\n|\x0b|\f|\r|\x85)
+</pre>
+This is an example of an "atomic group", details of which are given
+<a href="#atomicgroup">below.</a>
+This particular group matches either the two-character sequence CR followed by
+LF, or one of the single characters LF (linefeed, U+000A), VT (vertical tab,
+U+000B), FF (form feed, U+000C), CR (carriage return, U+000D), or NEL (next
+line, U+0085). The two-character sequence is treated as a single unit that
+cannot be split.
+</P>
+<P>
+In other modes, two additional characters whose codepoints are greater than 255
+are added: LS (line separator, U+2028) and PS (paragraph separator, U+2029).
+Unicode character property support is not needed for these characters to be
+recognized.
+</P>
+<P>
+It is possible to restrict \R to match only CR, LF, or CRLF (instead of the
+complete set of Unicode line endings) by setting the option PCRE_BSR_ANYCRLF
+either at compile time or when the pattern is matched. (BSR is an abbrevation
+for "backslash R".) This can be made the default when PCRE is built; if this is
+the case, the other behaviour can be requested via the PCRE_BSR_UNICODE option.
+It is also possible to specify these settings by starting a pattern string with
+one of the following sequences:
+<pre>
+  (*BSR_ANYCRLF)   CR, LF, or CRLF only
+  (*BSR_UNICODE)   any Unicode newline sequence
+</pre>
+These override the default and the options given to the compiling function, but
+they can themselves be overridden by options given to a matching function. Note
+that these special settings, which are not Perl-compatible, are recognized only
+at the very start of a pattern, and that they must be in upper case. If more
+than one of them is present, the last one is used. They can be combined with a
+change of newline convention; for example, a pattern can start with:
+<pre>
+  (*ANY)(*BSR_ANYCRLF)
+</pre>
+They can also be combined with the (*UTF8), (*UTF16), (*UTF32), (*UTF) or
+(*UCP) special sequences. Inside a character class, \R is treated as an
+unrecognized escape sequence, and so matches the letter "R" by default, but
+causes an error if PCRE_EXTRA is set.
+<a name="uniextseq"></a></P>
+<br><b>
+Unicode character properties
+</b><br>
+<P>
+When PCRE is built with Unicode character property support, three additional
+escape sequences that match characters with specific properties are available.
+When in 8-bit non-UTF-8 mode, these sequences are of course limited to testing
+characters whose codepoints are less than 256, but they do work in this mode.
+The extra escape sequences are:
+<pre>
+  \p{<i>xx</i>}   a character with the <i>xx</i> property
+  \P{<i>xx</i>}   a character without the <i>xx</i> property
+  \X       a Unicode extended grapheme cluster
+</pre>
+The property names represented by <i>xx</i> above are limited to the Unicode
+script names, the general category properties, "Any", which matches any
+character (including newline), and some special PCRE properties (described
+in the
+<a href="#extraprops">next section).</a>
+Other Perl properties such as "InMusicalSymbols" are not currently supported by
+PCRE. Note that \P{Any} does not match any characters, so always causes a
+match failure.
+</P>
+<P>
+Sets of Unicode characters are defined as belonging to certain scripts. A
+character from one of these sets can be matched using a script name. For
+example:
+<pre>
+  \p{Greek}
+  \P{Han}
+</pre>
+Those that are not part of an identified script are lumped together as
+"Common". The current list of scripts is:
+</P>
+<P>
+Arabic,
+Armenian,
+Avestan,
+Balinese,
+Bamum,
+Batak,
+Bengali,
+Bopomofo,
+Brahmi,
+Braille,
+Buginese,
+Buhid,
+Canadian_Aboriginal,
+Carian,
+Chakma,
+Cham,
+Cherokee,
+Common,
+Coptic,
+Cuneiform,
+Cypriot,
+Cyrillic,
+Deseret,
+Devanagari,
+Egyptian_Hieroglyphs,
+Ethiopic,
+Georgian,
+Glagolitic,
+Gothic,
+Greek,
+Gujarati,
+Gurmukhi,
+Han,
+Hangul,
+Hanunoo,
+Hebrew,
+Hiragana,
+Imperial_Aramaic,
+Inherited,
+Inscriptional_Pahlavi,
+Inscriptional_Parthian,
+Javanese,
+Kaithi,
+Kannada,
+Katakana,
+Kayah_Li,
+Kharoshthi,
+Khmer,
+Lao,
+Latin,
+Lepcha,
+Limbu,
+Linear_B,
+Lisu,
+Lycian,
+Lydian,
+Malayalam,
+Mandaic,
+Meetei_Mayek,
+Meroitic_Cursive,
+Meroitic_Hieroglyphs,
+Miao,
+Mongolian,
+Myanmar,
+New_Tai_Lue,
+Nko,
+Ogham,
+Old_Italic,
+Old_Persian,
+Old_South_Arabian,
+Old_Turkic,
+Ol_Chiki,
+Oriya,
+Osmanya,
+Phags_Pa,
+Phoenician,
+Rejang,
+Runic,
+Samaritan,
+Saurashtra,
+Sharada,
+Shavian,
+Sinhala,
+Sora_Sompeng,
+Sundanese,
+Syloti_Nagri,
+Syriac,
+Tagalog,
+Tagbanwa,
+Tai_Le,
+Tai_Tham,
+Tai_Viet,
+Takri,
+Tamil,
+Telugu,
+Thaana,
+Thai,
+Tibetan,
+Tifinagh,
+Ugaritic,
+Vai,
+Yi.
+</P>
+<P>
+Each character has exactly one Unicode general category property, specified by
+a two-letter abbreviation. For compatibility with Perl, negation can be
+specified by including a circumflex between the opening brace and the property
+name. For example, \p{^Lu} is the same as \P{Lu}.
+</P>
+<P>
+If only one letter is specified with \p or \P, it includes all the general
+category properties that start with that letter. In this case, in the absence
+of negation, the curly brackets in the escape sequence are optional; these two
+examples have the same effect:
+<pre>
+  \p{L}
+  \pL
+</pre>
+The following general category property codes are supported:
+<pre>
+  C     Other
+  Cc    Control
+  Cf    Format
+  Cn    Unassigned
+  Co    Private use
+  Cs    Surrogate
+
+  L     Letter
+  Ll    Lower case letter
+  Lm    Modifier letter
+  Lo    Other letter
+  Lt    Title case letter
+  Lu    Upper case letter
+
+  M     Mark
+  Mc    Spacing mark
+  Me    Enclosing mark
+  Mn    Non-spacing mark
+
+  N     Number
+  Nd    Decimal number
+  Nl    Letter number
+  No    Other number
+
+  P     Punctuation
+  Pc    Connector punctuation
+  Pd    Dash punctuation
+  Pe    Close punctuation
+  Pf    Final punctuation
+  Pi    Initial punctuation
+  Po    Other punctuation
+  Ps    Open punctuation
+
+  S     Symbol
+  Sc    Currency symbol
+  Sk    Modifier symbol
+  Sm    Mathematical symbol
+  So    Other symbol
+
+  Z     Separator
+  Zl    Line separator
+  Zp    Paragraph separator
+  Zs    Space separator
+</pre>
+The special property L& is also supported: it matches a character that has
+the Lu, Ll, or Lt property, in other words, a letter that is not classified as
+a modifier or "other".
+</P>
+<P>
+The Cs (Surrogate) property applies only to characters in the range U+D800 to
+U+DFFF. Such characters are not valid in Unicode strings and so
+cannot be tested by PCRE, unless UTF validity checking has been turned off
+(see the discussion of PCRE_NO_UTF8_CHECK, PCRE_NO_UTF16_CHECK and
+PCRE_NO_UTF32_CHECK in the
+<a href="pcreapi.html"><b>pcreapi</b></a>
+page). Perl does not support the Cs property.
+</P>
+<P>
+The long synonyms for property names that Perl supports (such as \p{Letter})
+are not supported by PCRE, nor is it permitted to prefix any of these
+properties with "Is".
+</P>
+<P>
+No character that is in the Unicode table has the Cn (unassigned) property.
+Instead, this property is assumed for any code point that is not in the
+Unicode table.
+</P>
+<P>
+Specifying caseless matching does not affect these escape sequences. For
+example, \p{Lu} always matches only upper case letters. This is different from
+the behaviour of current versions of Perl.
+</P>
+<P>
+Matching characters by Unicode property is not fast, because PCRE has to do a
+multistage table lookup in order to find a character's property. That is why
+the traditional escape sequences such as \d and \w do not use Unicode
+properties in PCRE by default, though you can make them do so by setting the
+PCRE_UCP option or by starting the pattern with (*UCP).
+</P>
+<br><b>
+Extended grapheme clusters
+</b><br>
+<P>
+The \X escape matches any number of Unicode characters that form an "extended
+grapheme cluster", and treats the sequence as an atomic group
+<a href="#atomicgroup">(see below).</a>
+Up to and including release 8.31, PCRE matched an earlier, simpler definition
+that was equivalent to
+<pre>
+  (?&#62;\PM\pM*)
+</pre>
+That is, it matched a character without the "mark" property, followed by zero
+or more characters with the "mark" property. Characters with the "mark"
+property are typically non-spacing accents that affect the preceding character.
+</P>
+<P>
+This simple definition was extended in Unicode to include more complicated
+kinds of composite character by giving each character a grapheme breaking
+property, and creating rules that use these properties to define the boundaries
+of extended grapheme clusters. In releases of PCRE later than 8.31, \X matches
+one of these clusters.
+</P>
+<P>
+\X always matches at least one character. Then it decides whether to add
+additional characters according to the following rules for ending a cluster:
+</P>
+<P>
+1. End at the end of the subject string.
+</P>
+<P>
+2. Do not end between CR and LF; otherwise end after any control character.
+</P>
+<P>
+3. Do not break Hangul (a Korean script) syllable sequences. Hangul characters
+are of five types: L, V, T, LV, and LVT. An L character may be followed by an
+L, V, LV, or LVT character; an LV or V character may be followed by a V or T
+character; an LVT or T character may be follwed only by a T character.
+</P>
+<P>
+4. Do not end before extending characters or spacing marks. Characters with
+the "mark" property always have the "extend" grapheme breaking property.
+</P>
+<P>
+5. Do not end after prepend characters.
+</P>
+<P>
+6. Otherwise, end the cluster.
+<a name="extraprops"></a></P>
+<br><b>
+PCRE's additional properties
+</b><br>
+<P>
+As well as the standard Unicode properties described above, PCRE supports four
+more that make it possible to convert traditional escape sequences such as \w
+and \s to use Unicode properties. PCRE uses these non-standard, non-Perl
+properties internally when PCRE_UCP is set. However, they may also be used
+explicitly. These properties are:
+<pre>
+  Xan   Any alphanumeric character
+  Xps   Any POSIX space character
+  Xsp   Any Perl space character
+  Xwd   Any Perl "word" character
+</pre>
+Xan matches characters that have either the L (letter) or the N (number)
+property. Xps matches the characters tab, linefeed, vertical tab, form feed, or
+carriage return, and any other character that has the Z (separator) property.
+Xsp is the same as Xps; it used to exclude vertical tab, for Perl
+compatibility, but Perl changed, and so PCRE followed at release 8.34. Xwd
+matches the same characters as Xan, plus underscore.
+</P>
+<P>
+There is another non-standard property, Xuc, which matches any character that
+can be represented by a Universal Character Name in C++ and other programming
+languages. These are the characters $, @, ` (grave accent), and all characters
+with Unicode code points greater than or equal to U+00A0, except for the
+surrogates U+D800 to U+DFFF. Note that most base (ASCII) characters are
+excluded. (Universal Character Names are of the form \uHHHH or \UHHHHHHHH
+where H is a hexadecimal digit. Note that the Xuc property does not match these
+sequences but the characters that they represent.)
+<a name="resetmatchstart"></a></P>
+<br><b>
+Resetting the match start
+</b><br>
+<P>
+The escape sequence \K causes any previously matched characters not to be
+included in the final matched sequence. For example, the pattern:
+<pre>
+  foo\Kbar
+</pre>
+matches "foobar", but reports that it has matched "bar". This feature is
+similar to a lookbehind assertion
+<a href="#lookbehind">(described below).</a>
+However, in this case, the part of the subject before the real match does not
+have to be of fixed length, as lookbehind assertions do. The use of \K does
+not interfere with the setting of
+<a href="#subpattern">captured substrings.</a>
+For example, when the pattern
+<pre>
+  (foo)\Kbar
+</pre>
+matches "foobar", the first substring is still set to "foo".
+</P>
+<P>
+Perl documents that the use of \K within assertions is "not well defined". In
+PCRE, \K is acted upon when it occurs inside positive assertions, but is
+ignored in negative assertions. Note that when a pattern such as (?=ab\K)
+matches, the reported start of the match can be greater than the end of the
+match.
+<a name="smallassertions"></a></P>
+<br><b>
+Simple assertions
+</b><br>
+<P>
+The final use of backslash is for certain simple assertions. An assertion
+specifies a condition that has to be met at a particular point in a match,
+without consuming any characters from the subject string. The use of
+subpatterns for more complicated assertions is described
+<a href="#bigassertions">below.</a>
+The backslashed assertions are:
+<pre>
+  \b     matches at a word boundary
+  \B     matches when not at a word boundary
+  \A     matches at the start of the subject
+  \Z     matches at the end of the subject
+          also matches before a newline at the end of the subject
+  \z     matches only at the end of the subject
+  \G     matches at the first matching position in the subject
+</pre>
+Inside a character class, \b has a different meaning; it matches the backspace
+character. If any other of these assertions appears in a character class, by
+default it matches the corresponding literal character (for example, \B
+matches the letter B). However, if the PCRE_EXTRA option is set, an "invalid
+escape sequence" error is generated instead.
+</P>
+<P>
+A word boundary is a position in the subject string where the current character
+and the previous character do not both match \w or \W (i.e. one matches
+\w and the other matches \W), or the start or end of the string if the
+first or last character matches \w, respectively. In a UTF mode, the meanings
+of \w and \W can be changed by setting the PCRE_UCP option. When this is
+done, it also affects \b and \B. Neither PCRE nor Perl has a separate "start
+of word" or "end of word" metasequence. However, whatever follows \b normally
+determines which it is. For example, the fragment \ba matches "a" at the start
+of a word.
+</P>
+<P>
+The \A, \Z, and \z assertions differ from the traditional circumflex and
+dollar (described in the next section) in that they only ever match at the very
+start and end of the subject string, whatever options are set. Thus, they are
+independent of multiline mode. These three assertions are not affected by the
+PCRE_NOTBOL or PCRE_NOTEOL options, which affect only the behaviour of the
+circumflex and dollar metacharacters. However, if the <i>startoffset</i>
+argument of <b>pcre_exec()</b> is non-zero, indicating that matching is to start
+at a point other than the beginning of the subject, \A can never match. The
+difference between \Z and \z is that \Z matches before a newline at the end
+of the string as well as at the very end, whereas \z matches only at the end.
+</P>
+<P>
+The \G assertion is true only when the current matching position is at the
+start point of the match, as specified by the <i>startoffset</i> argument of
+<b>pcre_exec()</b>. It differs from \A when the value of <i>startoffset</i> is
+non-zero. By calling <b>pcre_exec()</b> multiple times with appropriate
+arguments, you can mimic Perl's /g option, and it is in this kind of
+implementation where \G can be useful.
+</P>
+<P>
+Note, however, that PCRE's interpretation of \G, as the start of the current
+match, is subtly different from Perl's, which defines it as the end of the
+previous match. In Perl, these can be different when the previously matched
+string was empty. Because PCRE does just one match at a time, it cannot
+reproduce this behaviour.
+</P>
+<P>
+If all the alternatives of a pattern begin with \G, the expression is anchored
+to the starting match position, and the "anchored" flag is set in the compiled
+regular expression.
+</P>
+<br><a name="SEC6" href="#TOC1">CIRCUMFLEX AND DOLLAR</a><br>
+<P>
+The circumflex and dollar metacharacters are zero-width assertions. That is,
+they test for a particular condition being true without consuming any
+characters from the subject string.
+</P>
+<P>
+Outside a character class, in the default matching mode, the circumflex
+character is an assertion that is true only if the current matching point is at
+the start of the subject string. If the <i>startoffset</i> argument of
+<b>pcre_exec()</b> is non-zero, circumflex can never match if the PCRE_MULTILINE
+option is unset. Inside a character class, circumflex has an entirely different
+meaning
+<a href="#characterclass">(see below).</a>
+</P>
+<P>
+Circumflex need not be the first character of the pattern if a number of
+alternatives are involved, but it should be the first thing in each alternative
+in which it appears if the pattern is ever to match that branch. If all
+possible alternatives start with a circumflex, that is, if the pattern is
+constrained to match only at the start of the subject, it is said to be an
+"anchored" pattern. (There are also other constructs that can cause a pattern
+to be anchored.)
+</P>
+<P>
+The dollar character is an assertion that is true only if the current matching
+point is at the end of the subject string, or immediately before a newline at
+the end of the string (by default). Note, however, that it does not actually
+match the newline. Dollar need not be the last character of the pattern if a
+number of alternatives are involved, but it should be the last item in any
+branch in which it appears. Dollar has no special meaning in a character class.
+</P>
+<P>
+The meaning of dollar can be changed so that it matches only at the very end of
+the string, by setting the PCRE_DOLLAR_ENDONLY option at compile time. This
+does not affect the \Z assertion.
+</P>
+<P>
+The meanings of the circumflex and dollar characters are changed if the
+PCRE_MULTILINE option is set. When this is the case, a circumflex matches
+immediately after internal newlines as well as at the start of the subject
+string. It does not match after a newline that ends the string. A dollar
+matches before any newlines in the string, as well as at the very end, when
+PCRE_MULTILINE is set. When newline is specified as the two-character
+sequence CRLF, isolated CR and LF characters do not indicate newlines.
+</P>
+<P>
+For example, the pattern /^abc$/ matches the subject string "def\nabc" (where
+\n represents a newline) in multiline mode, but not otherwise. Consequently,
+patterns that are anchored in single line mode because all branches start with
+^ are not anchored in multiline mode, and a match for circumflex is possible
+when the <i>startoffset</i> argument of <b>pcre_exec()</b> is non-zero. The
+PCRE_DOLLAR_ENDONLY option is ignored if PCRE_MULTILINE is set.
+</P>
+<P>
+Note that the sequences \A, \Z, and \z can be used to match the start and
+end of the subject in both modes, and if all branches of a pattern start with
+\A it is always anchored, whether or not PCRE_MULTILINE is set.
+<a name="fullstopdot"></a></P>
+<br><a name="SEC7" href="#TOC1">FULL STOP (PERIOD, DOT) AND \N</a><br>
+<P>
+Outside a character class, a dot in the pattern matches any one character in
+the subject string except (by default) a character that signifies the end of a
+line.
+</P>
+<P>
+When a line ending is defined as a single character, dot never matches that
+character; when the two-character sequence CRLF is used, dot does not match CR
+if it is immediately followed by LF, but otherwise it matches all characters
+(including isolated CRs and LFs). When any Unicode line endings are being
+recognized, dot does not match CR or LF or any of the other line ending
+characters.
+</P>
+<P>
+The behaviour of dot with regard to newlines can be changed. If the PCRE_DOTALL
+option is set, a dot matches any one character, without exception. If the
+two-character sequence CRLF is present in the subject string, it takes two dots
+to match it.
+</P>
+<P>
+The handling of dot is entirely independent of the handling of circumflex and
+dollar, the only relationship being that they both involve newlines. Dot has no
+special meaning in a character class.
+</P>
+<P>
+The escape sequence \N behaves like a dot, except that it is not affected by
+the PCRE_DOTALL option. In other words, it matches any character except one
+that signifies the end of a line. Perl also uses \N to match characters by
+name; PCRE does not support this.
+</P>
+<br><a name="SEC8" href="#TOC1">MATCHING A SINGLE DATA UNIT</a><br>
+<P>
+Outside a character class, the escape sequence \C matches any one data unit,
+whether or not a UTF mode is set. In the 8-bit library, one data unit is one
+byte; in the 16-bit library it is a 16-bit unit; in the 32-bit library it is
+a 32-bit unit. Unlike a dot, \C always
+matches line-ending characters. The feature is provided in Perl in order to
+match individual bytes in UTF-8 mode, but it is unclear how it can usefully be
+used. Because \C breaks up characters into individual data units, matching one
+unit with \C in a UTF mode means that the rest of the string may start with a
+malformed UTF character. This has undefined results, because PCRE assumes that
+it is dealing with valid UTF strings (and by default it checks this at the
+start of processing unless the PCRE_NO_UTF8_CHECK, PCRE_NO_UTF16_CHECK or
+PCRE_NO_UTF32_CHECK option is used).
+</P>
+<P>
+PCRE does not allow \C to appear in lookbehind assertions
+<a href="#lookbehind">(described below)</a>
+in a UTF mode, because this would make it impossible to calculate the length of
+the lookbehind.
+</P>
+<P>
+In general, the \C escape sequence is best avoided. However, one
+way of using it that avoids the problem of malformed UTF characters is to use a
+lookahead to check the length of the next character, as in this pattern, which
+could be used with a UTF-8 string (ignore white space and line breaks):
+<pre>
+  (?| (?=[\x00-\x7f])(\C) |
+      (?=[\x80-\x{7ff}])(\C)(\C) |
+      (?=[\x{800}-\x{ffff}])(\C)(\C)(\C) |
+      (?=[\x{10000}-\x{1fffff}])(\C)(\C)(\C)(\C))
+</pre>
+A group that starts with (?| resets the capturing parentheses numbers in each
+alternative (see
+<a href="#dupsubpatternnumber">"Duplicate Subpattern Numbers"</a>
+below). The assertions at the start of each branch check the next UTF-8
+character for values whose encoding uses 1, 2, 3, or 4 bytes, respectively. The
+character's individual bytes are then captured by the appropriate number of
+groups.
+<a name="characterclass"></a></P>
+<br><a name="SEC9" href="#TOC1">SQUARE BRACKETS AND CHARACTER CLASSES</a><br>
+<P>
+An opening square bracket introduces a character class, terminated by a closing
+square bracket. A closing square bracket on its own is not special by default.
+However, if the PCRE_JAVASCRIPT_COMPAT option is set, a lone closing square
+bracket causes a compile-time error. If a closing square bracket is required as
+a member of the class, it should be the first data character in the class
+(after an initial circumflex, if present) or escaped with a backslash.
+</P>
+<P>
+A character class matches a single character in the subject. In a UTF mode, the
+character may be more than one data unit long. A matched character must be in
+the set of characters defined by the class, unless the first character in the
+class definition is a circumflex, in which case the subject character must not
+be in the set defined by the class. If a circumflex is actually required as a
+member of the class, ensure it is not the first character, or escape it with a
+backslash.
+</P>
+<P>
+For example, the character class [aeiou] matches any lower case vowel, while
+[^aeiou] matches any character that is not a lower case vowel. Note that a
+circumflex is just a convenient notation for specifying the characters that
+are in the class by enumerating those that are not. A class that starts with a
+circumflex is not an assertion; it still consumes a character from the subject
+string, and therefore it fails if the current pointer is at the end of the
+string.
+</P>
+<P>
+In UTF-8 (UTF-16, UTF-32) mode, characters with values greater than 255 (0xffff)
+can be included in a class as a literal string of data units, or by using the
+\x{ escaping mechanism.
+</P>
+<P>
+When caseless matching is set, any letters in a class represent both their
+upper case and lower case versions, so for example, a caseless [aeiou] matches
+"A" as well as "a", and a caseless [^aeiou] does not match "A", whereas a
+caseful version would. In a UTF mode, PCRE always understands the concept of
+case for characters whose values are less than 128, so caseless matching is
+always possible. For characters with higher values, the concept of case is
+supported if PCRE is compiled with Unicode property support, but not otherwise.
+If you want to use caseless matching in a UTF mode for characters 128 and
+above, you must ensure that PCRE is compiled with Unicode property support as
+well as with UTF support.
+</P>
+<P>
+Characters that might indicate line breaks are never treated in any special way
+when matching character classes, whatever line-ending sequence is in use, and
+whatever setting of the PCRE_DOTALL and PCRE_MULTILINE options is used. A class
+such as [^a] always matches one of these characters.
+</P>
+<P>
+The minus (hyphen) character can be used to specify a range of characters in a
+character class. For example, [d-m] matches any letter between d and m,
+inclusive. If a minus character is required in a class, it must be escaped with
+a backslash or appear in a position where it cannot be interpreted as
+indicating a range, typically as the first or last character in the class, or
+immediately after a range. For example, [b-d-z] matches letters in the range b
+to d, a hyphen character, or z.
+</P>
+<P>
+It is not possible to have the literal character "]" as the end character of a
+range. A pattern such as [W-]46] is interpreted as a class of two characters
+("W" and "-") followed by a literal string "46]", so it would match "W46]" or
+"-46]". However, if the "]" is escaped with a backslash it is interpreted as
+the end of range, so [W-\]46] is interpreted as a class containing a range
+followed by two other characters. The octal or hexadecimal representation of
+"]" can also be used to end a range.
+</P>
+<P>
+An error is generated if a POSIX character class (see below) or an escape
+sequence other than one that defines a single character appears at a point
+where a range ending character is expected. For example, [z-\xff] is valid,
+but [A-\d] and [A-[:digit:]] are not.
+</P>
+<P>
+Ranges operate in the collating sequence of character values. They can also be
+used for characters specified numerically, for example [\000-\037]. Ranges
+can include any characters that are valid for the current mode.
+</P>
+<P>
+If a range that includes letters is used when caseless matching is set, it
+matches the letters in either case. For example, [W-c] is equivalent to
+[][\\^_`wxyzabc], matched caselessly, and in a non-UTF mode, if character
+tables for a French locale are in use, [\xc8-\xcb] matches accented E
+characters in both cases. In UTF modes, PCRE supports the concept of case for
+characters with values greater than 128 only when it is compiled with Unicode
+property support.
+</P>
+<P>
+The character escape sequences \d, \D, \h, \H, \p, \P, \s, \S, \v,
+\V, \w, and \W may appear in a character class, and add the characters that
+they match to the class. For example, [\dABCDEF] matches any hexadecimal
+digit. In UTF modes, the PCRE_UCP option affects the meanings of \d, \s, \w
+and their upper case partners, just as it does when they appear outside a
+character class, as described in the section entitled
+<a href="#genericchartypes">"Generic character types"</a>
+above. The escape sequence \b has a different meaning inside a character
+class; it matches the backspace character. The sequences \B, \N, \R, and \X
+are not special inside a character class. Like any other unrecognized escape
+sequences, they are treated as the literal characters "B", "N", "R", and "X" by
+default, but cause an error if the PCRE_EXTRA option is set.
+</P>
+<P>
+A circumflex can conveniently be used with the upper case character types to
+specify a more restricted set of characters than the matching lower case type.
+For example, the class [^\W_] matches any letter or digit, but not underscore,
+whereas [\w] includes underscore. A positive character class should be read as
+"something OR something OR ..." and a negative class as "NOT something AND NOT
+something AND NOT ...".
+</P>
+<P>
+The only metacharacters that are recognized in character classes are backslash,
+hyphen (only where it can be interpreted as specifying a range), circumflex
+(only at the start), opening square bracket (only when it can be interpreted as
+introducing a POSIX class name, or for a special compatibility feature - see
+the next two sections), and the terminating closing square bracket. However,
+escaping other non-alphanumeric characters does no harm.
+</P>
+<br><a name="SEC10" href="#TOC1">POSIX CHARACTER CLASSES</a><br>
+<P>
+Perl supports the POSIX notation for character classes. This uses names
+enclosed by [: and :] within the enclosing square brackets. PCRE also supports
+this notation. For example,
+<pre>
+  [01[:alpha:]%]
+</pre>
+matches "0", "1", any alphabetic character, or "%". The supported class names
+are:
+<pre>
+  alnum    letters and digits
+  alpha    letters
+  ascii    character codes 0 - 127
+  blank    space or tab only
+  cntrl    control characters
+  digit    decimal digits (same as \d)
+  graph    printing characters, excluding space
+  lower    lower case letters
+  print    printing characters, including space
+  punct    printing characters, excluding letters and digits and space
+  space    white space (the same as \s from PCRE 8.34)
+  upper    upper case letters
+  word     "word" characters (same as \w)
+  xdigit   hexadecimal digits
+</pre>
+The default "space" characters are HT (9), LF (10), VT (11), FF (12), CR (13),
+and space (32). If locale-specific matching is taking place, the list of space
+characters may be different; there may be fewer or more of them. "Space" used
+to be different to \s, which did not include VT, for Perl compatibility.
+However, Perl changed at release 5.18, and PCRE followed at release 8.34.
+"Space" and \s now match the same set of characters.
+</P>
+<P>
+The name "word" is a Perl extension, and "blank" is a GNU extension from Perl
+5.8. Another Perl extension is negation, which is indicated by a ^ character
+after the colon. For example,
+<pre>
+  [12[:^digit:]]
+</pre>
+matches "1", "2", or any non-digit. PCRE (and Perl) also recognize the POSIX
+syntax [.ch.] and [=ch=] where "ch" is a "collating element", but these are not
+supported, and an error is given if they are encountered.
+</P>
+<P>
+By default, characters with values greater than 128 do not match any of the
+POSIX character classes. However, if the PCRE_UCP option is passed to
+<b>pcre_compile()</b>, some of the classes are changed so that Unicode character
+properties are used. This is achieved by replacing certain POSIX classes by
+other sequences, as follows:
+<pre>
+  [:alnum:]  becomes  \p{Xan}
+  [:alpha:]  becomes  \p{L}
+  [:blank:]  becomes  \h
+  [:digit:]  becomes  \p{Nd}
+  [:lower:]  becomes  \p{Ll}
+  [:space:]  becomes  \p{Xps}
+  [:upper:]  becomes  \p{Lu}
+  [:word:]   becomes  \p{Xwd}
+</pre>
+Negated versions, such as [:^alpha:] use \P instead of \p. Three other POSIX
+classes are handled specially in UCP mode:
+</P>
+<P>
+[:graph:]
+This matches characters that have glyphs that mark the page when printed. In
+Unicode property terms, it matches all characters with the L, M, N, P, S, or Cf
+properties, except for:
+<pre>
+  U+061C           Arabic Letter Mark
+  U+180E           Mongolian Vowel Separator
+  U+2066 - U+2069  Various "isolate"s
+
+</PRE>
+</P>
+<P>
+[:print:]
+This matches the same characters as [:graph:] plus space characters that are
+not controls, that is, characters with the Zs property.
+</P>
+<P>
+[:punct:]
+This matches all characters that have the Unicode P (punctuation) property,
+plus those characters whose code points are less than 128 that have the S
+(Symbol) property.
+</P>
+<P>
+The other POSIX classes are unchanged, and match only characters with code
+points less than 128.
+</P>
+<br><a name="SEC11" href="#TOC1">COMPATIBILITY FEATURE FOR WORD BOUNDARIES</a><br>
+<P>
+In the POSIX.2 compliant library that was included in 4.4BSD Unix, the ugly
+syntax [[:&#60;:]] and [[:&#62;:]] is used for matching "start of word" and "end of
+word". PCRE treats these items as follows:
+<pre>
+  [[:&#60;:]]  is converted to  \b(?=\w)
+  [[:&#62;:]]  is converted to  \b(?&#60;=\w)
+</pre>
+Only these exact character sequences are recognized. A sequence such as
+[a[:&#60;:]b] provokes error for an unrecognized POSIX class name. This support is
+not compatible with Perl. It is provided to help migrations from other
+environments, and is best not used in any new patterns. Note that \b matches
+at the start and the end of a word (see
+<a href="#smallassertions">"Simple assertions"</a>
+above), and in a Perl-style pattern the preceding or following character
+normally shows which is wanted, without the need for the assertions that are
+used above in order to give exactly the POSIX behaviour.
+</P>
+<br><a name="SEC12" href="#TOC1">VERTICAL BAR</a><br>
+<P>
+Vertical bar characters are used to separate alternative patterns. For example,
+the pattern
+<pre>
+  gilbert|sullivan
+</pre>
+matches either "gilbert" or "sullivan". Any number of alternatives may appear,
+and an empty alternative is permitted (matching the empty string). The matching
+process tries each alternative in turn, from left to right, and the first one
+that succeeds is used. If the alternatives are within a subpattern
+<a href="#subpattern">(defined below),</a>
+"succeeds" means matching the rest of the main pattern as well as the
+alternative in the subpattern.
+</P>
+<br><a name="SEC13" href="#TOC1">INTERNAL OPTION SETTING</a><br>
+<P>
+The settings of the PCRE_CASELESS, PCRE_MULTILINE, PCRE_DOTALL, and
+PCRE_EXTENDED options (which are Perl-compatible) can be changed from within
+the pattern by a sequence of Perl option letters enclosed between "(?" and ")".
+The option letters are
+<pre>
+  i  for PCRE_CASELESS
+  m  for PCRE_MULTILINE
+  s  for PCRE_DOTALL
+  x  for PCRE_EXTENDED
+</pre>
+For example, (?im) sets caseless, multiline matching. It is also possible to
+unset these options by preceding the letter with a hyphen, and a combined
+setting and unsetting such as (?im-sx), which sets PCRE_CASELESS and
+PCRE_MULTILINE while unsetting PCRE_DOTALL and PCRE_EXTENDED, is also
+permitted. If a letter appears both before and after the hyphen, the option is
+unset.
+</P>
+<P>
+The PCRE-specific options PCRE_DUPNAMES, PCRE_UNGREEDY, and PCRE_EXTRA can be
+changed in the same way as the Perl-compatible options by using the characters
+J, U and X respectively.
+</P>
+<P>
+When one of these option changes occurs at top level (that is, not inside
+subpattern parentheses), the change applies to the remainder of the pattern
+that follows. If the change is placed right at the start of a pattern, PCRE
+extracts it into the global options (and it will therefore show up in data
+extracted by the <b>pcre_fullinfo()</b> function).
+</P>
+<P>
+An option change within a subpattern (see below for a description of
+subpatterns) affects only that part of the subpattern that follows it, so
+<pre>
+  (a(?i)b)c
+</pre>
+matches abc and aBc and no other strings (assuming PCRE_CASELESS is not used).
+By this means, options can be made to have different settings in different
+parts of the pattern. Any changes made in one alternative do carry on
+into subsequent branches within the same subpattern. For example,
+<pre>
+  (a(?i)b|c)
+</pre>
+matches "ab", "aB", "c", and "C", even though when matching "C" the first
+branch is abandoned before the option setting. This is because the effects of
+option settings happen at compile time. There would be some very weird
+behaviour otherwise.
+</P>
+<P>
+<b>Note:</b> There are other PCRE-specific options that can be set by the
+application when the compiling or matching functions are called. In some cases
+the pattern can contain special leading sequences such as (*CRLF) to override
+what the application has set or what has been defaulted. Details are given in
+the section entitled
+<a href="#newlineseq">"Newline sequences"</a>
+above. There are also the (*UTF8), (*UTF16),(*UTF32), and (*UCP) leading
+sequences that can be used to set UTF and Unicode property modes; they are
+equivalent to setting the PCRE_UTF8, PCRE_UTF16, PCRE_UTF32 and the PCRE_UCP
+options, respectively. The (*UTF) sequence is a generic version that can be
+used with any of the libraries. However, the application can set the
+PCRE_NEVER_UTF option, which locks out the use of the (*UTF) sequences.
+<a name="subpattern"></a></P>
+<br><a name="SEC14" href="#TOC1">SUBPATTERNS</a><br>
+<P>
+Subpatterns are delimited by parentheses (round brackets), which can be nested.
+Turning part of a pattern into a subpattern does two things:
+<br>
+<br>
+1. It localizes a set of alternatives. For example, the pattern
+<pre>
+  cat(aract|erpillar|)
+</pre>
+matches "cataract", "caterpillar", or "cat". Without the parentheses, it would
+match "cataract", "erpillar" or an empty string.
+<br>
+<br>
+2. It sets up the subpattern as a capturing subpattern. This means that, when
+the whole pattern matches, that portion of the subject string that matched the
+subpattern is passed back to the caller via the <i>ovector</i> argument of the
+matching function. (This applies only to the traditional matching functions;
+the DFA matching functions do not support capturing.)
+</P>
+<P>
+Opening parentheses are counted from left to right (starting from 1) to obtain
+numbers for the capturing subpatterns. For example, if the string "the red
+king" is matched against the pattern
+<pre>
+  the ((red|white) (king|queen))
+</pre>
+the captured substrings are "red king", "red", and "king", and are numbered 1,
+2, and 3, respectively.
+</P>
+<P>
+The fact that plain parentheses fulfil two functions is not always helpful.
+There are often times when a grouping subpattern is required without a
+capturing requirement. If an opening parenthesis is followed by a question mark
+and a colon, the subpattern does not do any capturing, and is not counted when
+computing the number of any subsequent capturing subpatterns. For example, if
+the string "the white queen" is matched against the pattern
+<pre>
+  the ((?:red|white) (king|queen))
+</pre>
+the captured substrings are "white queen" and "queen", and are numbered 1 and
+2. The maximum number of capturing subpatterns is 65535.
+</P>
+<P>
+As a convenient shorthand, if any option settings are required at the start of
+a non-capturing subpattern, the option letters may appear between the "?" and
+the ":". Thus the two patterns
+<pre>
+  (?i:saturday|sunday)
+  (?:(?i)saturday|sunday)
+</pre>
+match exactly the same set of strings. Because alternative branches are tried
+from left to right, and options are not reset until the end of the subpattern
+is reached, an option setting in one branch does affect subsequent branches, so
+the above patterns match "SUNDAY" as well as "Saturday".
+<a name="dupsubpatternnumber"></a></P>
+<br><a name="SEC15" href="#TOC1">DUPLICATE SUBPATTERN NUMBERS</a><br>
+<P>
+Perl 5.10 introduced a feature whereby each alternative in a subpattern uses
+the same numbers for its capturing parentheses. Such a subpattern starts with
+(?| and is itself a non-capturing subpattern. For example, consider this
+pattern:
+<pre>
+  (?|(Sat)ur|(Sun))day
+</pre>
+Because the two alternatives are inside a (?| group, both sets of capturing
+parentheses are numbered one. Thus, when the pattern matches, you can look
+at captured substring number one, whichever alternative matched. This construct
+is useful when you want to capture part, but not all, of one of a number of
+alternatives. Inside a (?| group, parentheses are numbered as usual, but the
+number is reset at the start of each branch. The numbers of any capturing
+parentheses that follow the subpattern start after the highest number used in
+any branch. The following example is taken from the Perl documentation. The
+numbers underneath show in which buffer the captured content will be stored.
+<pre>
+  # before  ---------------branch-reset----------- after
+  / ( a )  (?| x ( y ) z | (p (q) r) | (t) u (v) ) ( z ) /x
+  # 1            2         2  3        2     3     4
+</pre>
+A back reference to a numbered subpattern uses the most recent value that is
+set for that number by any subpattern. The following pattern matches "abcabc"
+or "defdef":
+<pre>
+  /(?|(abc)|(def))\1/
+</pre>
+In contrast, a subroutine call to a numbered subpattern always refers to the
+first one in the pattern with the given number. The following pattern matches
+"abcabc" or "defabc":
+<pre>
+  /(?|(abc)|(def))(?1)/
+</pre>
+If a
+<a href="#conditions">condition test</a>
+for a subpattern's having matched refers to a non-unique number, the test is
+true if any of the subpatterns of that number have matched.
+</P>
+<P>
+An alternative approach to using this "branch reset" feature is to use
+duplicate named subpatterns, as described in the next section.
+</P>
+<br><a name="SEC16" href="#TOC1">NAMED SUBPATTERNS</a><br>
+<P>
+Identifying capturing parentheses by number is simple, but it can be very hard
+to keep track of the numbers in complicated regular expressions. Furthermore,
+if an expression is modified, the numbers may change. To help with this
+difficulty, PCRE supports the naming of subpatterns. This feature was not
+added to Perl until release 5.10. Python had the feature earlier, and PCRE
+introduced it at release 4.0, using the Python syntax. PCRE now supports both
+the Perl and the Python syntax. Perl allows identically numbered subpatterns to
+have different names, but PCRE does not.
+</P>
+<P>
+In PCRE, a subpattern can be named in one of three ways: (?&#60;name&#62;...) or
+(?'name'...) as in Perl, or (?P&#60;name&#62;...) as in Python. References to capturing
+parentheses from other parts of the pattern, such as
+<a href="#backreferences">back references,</a>
+<a href="#recursion">recursion,</a>
+and
+<a href="#conditions">conditions,</a>
+can be made by name as well as by number.
+</P>
+<P>
+Names consist of up to 32 alphanumeric characters and underscores, but must
+start with a non-digit. Named capturing parentheses are still allocated numbers
+as well as names, exactly as if the names were not present. The PCRE API
+provides function calls for extracting the name-to-number translation table
+from a compiled pattern. There is also a convenience function for extracting a
+captured substring by name.
+</P>
+<P>
+By default, a name must be unique within a pattern, but it is possible to relax
+this constraint by setting the PCRE_DUPNAMES option at compile time. (Duplicate
+names are also always permitted for subpatterns with the same number, set up as
+described in the previous section.) Duplicate names can be useful for patterns
+where only one instance of the named parentheses can match. Suppose you want to
+match the name of a weekday, either as a 3-letter abbreviation or as the full
+name, and in both cases you want to extract the abbreviation. This pattern
+(ignoring the line breaks) does the job:
+<pre>
+  (?&#60;DN&#62;Mon|Fri|Sun)(?:day)?|
+  (?&#60;DN&#62;Tue)(?:sday)?|
+  (?&#60;DN&#62;Wed)(?:nesday)?|
+  (?&#60;DN&#62;Thu)(?:rsday)?|
+  (?&#60;DN&#62;Sat)(?:urday)?
+</pre>
+There are five capturing substrings, but only one is ever set after a match.
+(An alternative way of solving this problem is to use a "branch reset"
+subpattern, as described in the previous section.)
+</P>
+<P>
+The convenience function for extracting the data by name returns the substring
+for the first (and in this example, the only) subpattern of that name that
+matched. This saves searching to find which numbered subpattern it was.
+</P>
+<P>
+If you make a back reference to a non-unique named subpattern from elsewhere in
+the pattern, the subpatterns to which the name refers are checked in the order
+in which they appear in the overall pattern. The first one that is set is used
+for the reference. For example, this pattern matches both "foofoo" and
+"barbar" but not "foobar" or "barfoo":
+<pre>
+  (?:(?&#60;n&#62;foo)|(?&#60;n&#62;bar))\k&#60;n&#62;
+
+</PRE>
+</P>
+<P>
+If you make a subroutine call to a non-unique named subpattern, the one that
+corresponds to the first occurrence of the name is used. In the absence of
+duplicate numbers (see the previous section) this is the one with the lowest
+number.
+</P>
+<P>
+If you use a named reference in a condition
+test (see the
+<a href="#conditions">section about conditions</a>
+below), either to check whether a subpattern has matched, or to check for
+recursion, all subpatterns with the same name are tested. If the condition is
+true for any one of them, the overall condition is true. This is the same
+behaviour as testing by number. For further details of the interfaces for
+handling named subpatterns, see the
+<a href="pcreapi.html"><b>pcreapi</b></a>
+documentation.
+</P>
+<P>
+<b>Warning:</b> You cannot use different names to distinguish between two
+subpatterns with the same number because PCRE uses only the numbers when
+matching. For this reason, an error is given at compile time if different names
+are given to subpatterns with the same number. However, you can always give the
+same name to subpatterns with the same number, even when PCRE_DUPNAMES is not
+set.
+</P>
+<br><a name="SEC17" href="#TOC1">REPETITION</a><br>
+<P>
+Repetition is specified by quantifiers, which can follow any of the following
+items:
+<pre>
+  a literal data character
+  the dot metacharacter
+  the \C escape sequence
+  the \X escape sequence
+  the \R escape sequence
+  an escape such as \d or \pL that matches a single character
+  a character class
+  a back reference (see next section)
+  a parenthesized subpattern (including assertions)
+  a subroutine call to a subpattern (recursive or otherwise)
+</pre>
+The general repetition quantifier specifies a minimum and maximum number of
+permitted matches, by giving the two numbers in curly brackets (braces),
+separated by a comma. The numbers must be less than 65536, and the first must
+be less than or equal to the second. For example:
+<pre>
+  z{2,4}
+</pre>
+matches "zz", "zzz", or "zzzz". A closing brace on its own is not a special
+character. If the second number is omitted, but the comma is present, there is
+no upper limit; if the second number and the comma are both omitted, the
+quantifier specifies an exact number of required matches. Thus
+<pre>
+  [aeiou]{3,}
+</pre>
+matches at least 3 successive vowels, but may match many more, while
+<pre>
+  \d{8}
+</pre>
+matches exactly 8 digits. An opening curly bracket that appears in a position
+where a quantifier is not allowed, or one that does not match the syntax of a
+quantifier, is taken as a literal character. For example, {,6} is not a
+quantifier, but a literal string of four characters.
+</P>
+<P>
+In UTF modes, quantifiers apply to characters rather than to individual data
+units. Thus, for example, \x{100}{2} matches two characters, each of
+which is represented by a two-byte sequence in a UTF-8 string. Similarly,
+\X{3} matches three Unicode extended grapheme clusters, each of which may be
+several data units long (and they may be of different lengths).
+</P>
+<P>
+The quantifier {0} is permitted, causing the expression to behave as if the
+previous item and the quantifier were not present. This may be useful for
+subpatterns that are referenced as
+<a href="#subpatternsassubroutines">subroutines</a>
+from elsewhere in the pattern (but see also the section entitled
+<a href="#subdefine">"Defining subpatterns for use by reference only"</a>
+below). Items other than subpatterns that have a {0} quantifier are omitted
+from the compiled pattern.
+</P>
+<P>
+For convenience, the three most common quantifiers have single-character
+abbreviations:
+<pre>
+  *    is equivalent to {0,}
+  +    is equivalent to {1,}
+  ?    is equivalent to {0,1}
+</pre>
+It is possible to construct infinite loops by following a subpattern that can
+match no characters with a quantifier that has no upper limit, for example:
+<pre>
+  (a?)*
+</pre>
+Earlier versions of Perl and PCRE used to give an error at compile time for
+such patterns. However, because there are cases where this can be useful, such
+patterns are now accepted, but if any repetition of the subpattern does in fact
+match no characters, the loop is forcibly broken.
+</P>
+<P>
+By default, the quantifiers are "greedy", that is, they match as much as
+possible (up to the maximum number of permitted times), without causing the
+rest of the pattern to fail. The classic example of where this gives problems
+is in trying to match comments in C programs. These appear between /* and */
+and within the comment, individual * and / characters may appear. An attempt to
+match C comments by applying the pattern
+<pre>
+  /\*.*\*/
+</pre>
+to the string
+<pre>
+  /* first comment */  not comment  /* second comment */
+</pre>
+fails, because it matches the entire string owing to the greediness of the .*
+item.
+</P>
+<P>
+However, if a quantifier is followed by a question mark, it ceases to be
+greedy, and instead matches the minimum number of times possible, so the
+pattern
+<pre>
+  /\*.*?\*/
+</pre>
+does the right thing with the C comments. The meaning of the various
+quantifiers is not otherwise changed, just the preferred number of matches.
+Do not confuse this use of question mark with its use as a quantifier in its
+own right. Because it has two uses, it can sometimes appear doubled, as in
+<pre>
+  \d??\d
+</pre>
+which matches one digit by preference, but can match two if that is the only
+way the rest of the pattern matches.
+</P>
+<P>
+If the PCRE_UNGREEDY option is set (an option that is not available in Perl),
+the quantifiers are not greedy by default, but individual ones can be made
+greedy by following them with a question mark. In other words, it inverts the
+default behaviour.
+</P>
+<P>
+When a parenthesized subpattern is quantified with a minimum repeat count that
+is greater than 1 or with a limited maximum, more memory is required for the
+compiled pattern, in proportion to the size of the minimum or maximum.
+</P>
+<P>
+If a pattern starts with .* or .{0,} and the PCRE_DOTALL option (equivalent
+to Perl's /s) is set, thus allowing the dot to match newlines, the pattern is
+implicitly anchored, because whatever follows will be tried against every
+character position in the subject string, so there is no point in retrying the
+overall match at any position after the first. PCRE normally treats such a
+pattern as though it were preceded by \A.
+</P>
+<P>
+In cases where it is known that the subject string contains no newlines, it is
+worth setting PCRE_DOTALL in order to obtain this optimization, or
+alternatively using ^ to indicate anchoring explicitly.
+</P>
+<P>
+However, there are some cases where the optimization cannot be used. When .*
+is inside capturing parentheses that are the subject of a back reference
+elsewhere in the pattern, a match at the start may fail where a later one
+succeeds. Consider, for example:
+<pre>
+  (.*)abc\1
+</pre>
+If the subject is "xyz123abc123" the match point is the fourth character. For
+this reason, such a pattern is not implicitly anchored.
+</P>
+<P>
+Another case where implicit anchoring is not applied is when the leading .* is
+inside an atomic group. Once again, a match at the start may fail where a later
+one succeeds. Consider this pattern:
+<pre>
+  (?&#62;.*?a)b
+</pre>
+It matches "ab" in the subject "aab". The use of the backtracking control verbs
+(*PRUNE) and (*SKIP) also disable this optimization.
+</P>
+<P>
+When a capturing subpattern is repeated, the value captured is the substring
+that matched the final iteration. For example, after
+<pre>
+  (tweedle[dume]{3}\s*)+
+</pre>
+has matched "tweedledum tweedledee" the value of the captured substring is
+"tweedledee". However, if there are nested capturing subpatterns, the
+corresponding captured values may have been set in previous iterations. For
+example, after
+<pre>
+  /(a|(b))+/
+</pre>
+matches "aba" the value of the second captured substring is "b".
+<a name="atomicgroup"></a></P>
+<br><a name="SEC18" href="#TOC1">ATOMIC GROUPING AND POSSESSIVE QUANTIFIERS</a><br>
+<P>
+With both maximizing ("greedy") and minimizing ("ungreedy" or "lazy")
+repetition, failure of what follows normally causes the repeated item to be
+re-evaluated to see if a different number of repeats allows the rest of the
+pattern to match. Sometimes it is useful to prevent this, either to change the
+nature of the match, or to cause it fail earlier than it otherwise might, when
+the author of the pattern knows there is no point in carrying on.
+</P>
+<P>
+Consider, for example, the pattern \d+foo when applied to the subject line
+<pre>
+  123456bar
+</pre>
+After matching all 6 digits and then failing to match "foo", the normal
+action of the matcher is to try again with only 5 digits matching the \d+
+item, and then with 4, and so on, before ultimately failing. "Atomic grouping"
+(a term taken from Jeffrey Friedl's book) provides the means for specifying
+that once a subpattern has matched, it is not to be re-evaluated in this way.
+</P>
+<P>
+If we use atomic grouping for the previous example, the matcher gives up
+immediately on failing to match "foo" the first time. The notation is a kind of
+special parenthesis, starting with (?&#62; as in this example:
+<pre>
+  (?&#62;\d+)foo
+</pre>
+This kind of parenthesis "locks up" the  part of the pattern it contains once
+it has matched, and a failure further into the pattern is prevented from
+backtracking into it. Backtracking past it to previous items, however, works as
+normal.
+</P>
+<P>
+An alternative description is that a subpattern of this type matches the string
+of characters that an identical standalone pattern would match, if anchored at
+the current point in the subject string.
+</P>
+<P>
+Atomic grouping subpatterns are not capturing subpatterns. Simple cases such as
+the above example can be thought of as a maximizing repeat that must swallow
+everything it can. So, while both \d+ and \d+? are prepared to adjust the
+number of digits they match in order to make the rest of the pattern match,
+(?&#62;\d+) can only match an entire sequence of digits.
+</P>
+<P>
+Atomic groups in general can of course contain arbitrarily complicated
+subpatterns, and can be nested. However, when the subpattern for an atomic
+group is just a single repeated item, as in the example above, a simpler
+notation, called a "possessive quantifier" can be used. This consists of an
+additional + character following a quantifier. Using this notation, the
+previous example can be rewritten as
+<pre>
+  \d++foo
+</pre>
+Note that a possessive quantifier can be used with an entire group, for
+example:
+<pre>
+  (abc|xyz){2,3}+
+</pre>
+Possessive quantifiers are always greedy; the setting of the PCRE_UNGREEDY
+option is ignored. They are a convenient notation for the simpler forms of
+atomic group. However, there is no difference in the meaning of a possessive
+quantifier and the equivalent atomic group, though there may be a performance
+difference; possessive quantifiers should be slightly faster.
+</P>
+<P>
+The possessive quantifier syntax is an extension to the Perl 5.8 syntax.
+Jeffrey Friedl originated the idea (and the name) in the first edition of his
+book. Mike McCloskey liked it, so implemented it when he built Sun's Java
+package, and PCRE copied it from there. It ultimately found its way into Perl
+at release 5.10.
+</P>
+<P>
+PCRE has an optimization that automatically "possessifies" certain simple
+pattern constructs. For example, the sequence A+B is treated as A++B because
+there is no point in backtracking into a sequence of A's when B must follow.
+</P>
+<P>
+When a pattern contains an unlimited repeat inside a subpattern that can itself
+be repeated an unlimited number of times, the use of an atomic group is the
+only way to avoid some failing matches taking a very long time indeed. The
+pattern
+<pre>
+  (\D+|&#60;\d+&#62;)*[!?]
+</pre>
+matches an unlimited number of substrings that either consist of non-digits, or
+digits enclosed in &#60;&#62;, followed by either ! or ?. When it matches, it runs
+quickly. However, if it is applied to
+<pre>
+  aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+</pre>
+it takes a long time before reporting failure. This is because the string can
+be divided between the internal \D+ repeat and the external * repeat in a
+large number of ways, and all have to be tried. (The example uses [!?] rather
+than a single character at the end, because both PCRE and Perl have an
+optimization that allows for fast failure when a single character is used. They
+remember the last single character that is required for a match, and fail early
+if it is not present in the string.) If the pattern is changed so that it uses
+an atomic group, like this:
+<pre>
+  ((?&#62;\D+)|&#60;\d+&#62;)*[!?]
+</pre>
+sequences of non-digits cannot be broken, and failure happens quickly.
+<a name="backreferences"></a></P>
+<br><a name="SEC19" href="#TOC1">BACK REFERENCES</a><br>
+<P>
+Outside a character class, a backslash followed by a digit greater than 0 (and
+possibly further digits) is a back reference to a capturing subpattern earlier
+(that is, to its left) in the pattern, provided there have been that many
+previous capturing left parentheses.
+</P>
+<P>
+However, if the decimal number following the backslash is less than 10, it is
+always taken as a back reference, and causes an error only if there are not
+that many capturing left parentheses in the entire pattern. In other words, the
+parentheses that are referenced need not be to the left of the reference for
+numbers less than 10. A "forward back reference" of this type can make sense
+when a repetition is involved and the subpattern to the right has participated
+in an earlier iteration.
+</P>
+<P>
+It is not possible to have a numerical "forward back reference" to a subpattern
+whose number is 10 or more using this syntax because a sequence such as \50 is
+interpreted as a character defined in octal. See the subsection entitled
+"Non-printing characters"
+<a href="#digitsafterbackslash">above</a>
+for further details of the handling of digits following a backslash. There is
+no such problem when named parentheses are used. A back reference to any
+subpattern is possible using named parentheses (see below).
+</P>
+<P>
+Another way of avoiding the ambiguity inherent in the use of digits following a
+backslash is to use the \g escape sequence. This escape must be followed by an
+unsigned number or a negative number, optionally enclosed in braces. These
+examples are all identical:
+<pre>
+  (ring), \1
+  (ring), \g1
+  (ring), \g{1}
+</pre>
+An unsigned number specifies an absolute reference without the ambiguity that
+is present in the older syntax. It is also useful when literal digits follow
+the reference. A negative number is a relative reference. Consider this
+example:
+<pre>
+  (abc(def)ghi)\g{-1}
+</pre>
+The sequence \g{-1} is a reference to the most recently started capturing
+subpattern before \g, that is, is it equivalent to \2 in this example.
+Similarly, \g{-2} would be equivalent to \1. The use of relative references
+can be helpful in long patterns, and also in patterns that are created by
+joining together fragments that contain references within themselves.
+</P>
+<P>
+A back reference matches whatever actually matched the capturing subpattern in
+the current subject string, rather than anything matching the subpattern
+itself (see
+<a href="#subpatternsassubroutines">"Subpatterns as subroutines"</a>
+below for a way of doing that). So the pattern
+<pre>
+  (sens|respons)e and \1ibility
+</pre>
+matches "sense and sensibility" and "response and responsibility", but not
+"sense and responsibility". If caseful matching is in force at the time of the
+back reference, the case of letters is relevant. For example,
+<pre>
+  ((?i)rah)\s+\1
+</pre>
+matches "rah rah" and "RAH RAH", but not "RAH rah", even though the original
+capturing subpattern is matched caselessly.
+</P>
+<P>
+There are several different ways of writing back references to named
+subpatterns. The .NET syntax \k{name} and the Perl syntax \k&#60;name&#62; or
+\k'name' are supported, as is the Python syntax (?P=name). Perl 5.10's unified
+back reference syntax, in which \g can be used for both numeric and named
+references, is also supported. We could rewrite the above example in any of
+the following ways:
+<pre>
+  (?&#60;p1&#62;(?i)rah)\s+\k&#60;p1&#62;
+  (?'p1'(?i)rah)\s+\k{p1}
+  (?P&#60;p1&#62;(?i)rah)\s+(?P=p1)
+  (?&#60;p1&#62;(?i)rah)\s+\g{p1}
+</pre>
+A subpattern that is referenced by name may appear in the pattern before or
+after the reference.
+</P>
+<P>
+There may be more than one back reference to the same subpattern. If a
+subpattern has not actually been used in a particular match, any back
+references to it always fail by default. For example, the pattern
+<pre>
+  (a|(bc))\2
+</pre>
+always fails if it starts to match "a" rather than "bc". However, if the
+PCRE_JAVASCRIPT_COMPAT option is set at compile time, a back reference to an
+unset value matches an empty string.
+</P>
+<P>
+Because there may be many capturing parentheses in a pattern, all digits
+following a backslash are taken as part of a potential back reference number.
+If the pattern continues with a digit character, some delimiter must be used to
+terminate the back reference. If the PCRE_EXTENDED option is set, this can be
+white space. Otherwise, the \g{ syntax or an empty comment (see
+<a href="#comments">"Comments"</a>
+below) can be used.
+</P>
+<br><b>
+Recursive back references
+</b><br>
+<P>
+A back reference that occurs inside the parentheses to which it refers fails
+when the subpattern is first used, so, for example, (a\1) never matches.
+However, such references can be useful inside repeated subpatterns. For
+example, the pattern
+<pre>
+  (a|b\1)+
+</pre>
+matches any number of "a"s and also "aba", "ababbaa" etc. At each iteration of
+the subpattern, the back reference matches the character string corresponding
+to the previous iteration. In order for this to work, the pattern must be such
+that the first iteration does not need to match the back reference. This can be
+done using alternation, as in the example above, or by a quantifier with a
+minimum of zero.
+</P>
+<P>
+Back references of this type cause the group that they reference to be treated
+as an
+<a href="#atomicgroup">atomic group.</a>
+Once the whole group has been matched, a subsequent matching failure cannot
+cause backtracking into the middle of the group.
+<a name="bigassertions"></a></P>
+<br><a name="SEC20" href="#TOC1">ASSERTIONS</a><br>
+<P>
+An assertion is a test on the characters following or preceding the current
+matching point that does not actually consume any characters. The simple
+assertions coded as \b, \B, \A, \G, \Z, \z, ^ and $ are described
+<a href="#smallassertions">above.</a>
+</P>
+<P>
+More complicated assertions are coded as subpatterns. There are two kinds:
+those that look ahead of the current position in the subject string, and those
+that look behind it. An assertion subpattern is matched in the normal way,
+except that it does not cause the current matching position to be changed.
+</P>
+<P>
+Assertion subpatterns are not capturing subpatterns. If such an assertion
+contains capturing subpatterns within it, these are counted for the purposes of
+numbering the capturing subpatterns in the whole pattern. However, substring
+capturing is carried out only for positive assertions. (Perl sometimes, but not
+always, does do capturing in negative assertions.)
+</P>
+<P>
+For compatibility with Perl, assertion subpatterns may be repeated; though
+it makes no sense to assert the same thing several times, the side effect of
+capturing parentheses may occasionally be useful. In practice, there only three
+cases:
+<br>
+<br>
+(1) If the quantifier is {0}, the assertion is never obeyed during matching.
+However, it may contain internal capturing parenthesized groups that are called
+from elsewhere via the
+<a href="#subpatternsassubroutines">subroutine mechanism.</a>
+<br>
+<br>
+(2) If quantifier is {0,n} where n is greater than zero, it is treated as if it
+were {0,1}. At run time, the rest of the pattern match is tried with and
+without the assertion, the order depending on the greediness of the quantifier.
+<br>
+<br>
+(3) If the minimum repetition is greater than zero, the quantifier is ignored.
+The assertion is obeyed just once when encountered during matching.
+</P>
+<br><b>
+Lookahead assertions
+</b><br>
+<P>
+Lookahead assertions start with (?= for positive assertions and (?! for
+negative assertions. For example,
+<pre>
+  \w+(?=;)
+</pre>
+matches a word followed by a semicolon, but does not include the semicolon in
+the match, and
+<pre>
+  foo(?!bar)
+</pre>
+matches any occurrence of "foo" that is not followed by "bar". Note that the
+apparently similar pattern
+<pre>
+  (?!foo)bar
+</pre>
+does not find an occurrence of "bar" that is preceded by something other than
+"foo"; it finds any occurrence of "bar" whatsoever, because the assertion
+(?!foo) is always true when the next three characters are "bar". A
+lookbehind assertion is needed to achieve the other effect.
+</P>
+<P>
+If you want to force a matching failure at some point in a pattern, the most
+convenient way to do it is with (?!) because an empty string always matches, so
+an assertion that requires there not to be an empty string must always fail.
+The backtracking control verb (*FAIL) or (*F) is a synonym for (?!).
+<a name="lookbehind"></a></P>
+<br><b>
+Lookbehind assertions
+</b><br>
+<P>
+Lookbehind assertions start with (?&#60;= for positive assertions and (?&#60;! for
+negative assertions. For example,
+<pre>
+  (?&#60;!foo)bar
+</pre>
+does find an occurrence of "bar" that is not preceded by "foo". The contents of
+a lookbehind assertion are restricted such that all the strings it matches must
+have a fixed length. However, if there are several top-level alternatives, they
+do not all have to have the same fixed length. Thus
+<pre>
+  (?&#60;=bullock|donkey)
+</pre>
+is permitted, but
+<pre>
+  (?&#60;!dogs?|cats?)
+</pre>
+causes an error at compile time. Branches that match different length strings
+are permitted only at the top level of a lookbehind assertion. This is an
+extension compared with Perl, which requires all branches to match the same
+length of string. An assertion such as
+<pre>
+  (?&#60;=ab(c|de))
+</pre>
+is not permitted, because its single top-level branch can match two different
+lengths, but it is acceptable to PCRE if rewritten to use two top-level
+branches:
+<pre>
+  (?&#60;=abc|abde)
+</pre>
+In some cases, the escape sequence \K
+<a href="#resetmatchstart">(see above)</a>
+can be used instead of a lookbehind assertion to get round the fixed-length
+restriction.
+</P>
+<P>
+The implementation of lookbehind assertions is, for each alternative, to
+temporarily move the current position back by the fixed length and then try to
+match. If there are insufficient characters before the current position, the
+assertion fails.
+</P>
+<P>
+In a UTF mode, PCRE does not allow the \C escape (which matches a single data
+unit even in a UTF mode) to appear in lookbehind assertions, because it makes
+it impossible to calculate the length of the lookbehind. The \X and \R
+escapes, which can match different numbers of data units, are also not
+permitted.
+</P>
+<P>
+<a href="#subpatternsassubroutines">"Subroutine"</a>
+calls (see below) such as (?2) or (?&X) are permitted in lookbehinds, as long
+as the subpattern matches a fixed-length string.
+<a href="#recursion">Recursion,</a>
+however, is not supported.
+</P>
+<P>
+Possessive quantifiers can be used in conjunction with lookbehind assertions to
+specify efficient matching of fixed-length strings at the end of subject
+strings. Consider a simple pattern such as
+<pre>
+  abcd$
+</pre>
+when applied to a long string that does not match. Because matching proceeds
+from left to right, PCRE will look for each "a" in the subject and then see if
+what follows matches the rest of the pattern. If the pattern is specified as
+<pre>
+  ^.*abcd$
+</pre>
+the initial .* matches the entire string at first, but when this fails (because
+there is no following "a"), it backtracks to match all but the last character,
+then all but the last two characters, and so on. Once again the search for "a"
+covers the entire string, from right to left, so we are no better off. However,
+if the pattern is written as
+<pre>
+  ^.*+(?&#60;=abcd)
+</pre>
+there can be no backtracking for the .*+ item; it can match only the entire
+string. The subsequent lookbehind assertion does a single test on the last four
+characters. If it fails, the match fails immediately. For long strings, this
+approach makes a significant difference to the processing time.
+</P>
+<br><b>
+Using multiple assertions
+</b><br>
+<P>
+Several assertions (of any sort) may occur in succession. For example,
+<pre>
+  (?&#60;=\d{3})(?&#60;!999)foo
+</pre>
+matches "foo" preceded by three digits that are not "999". Notice that each of
+the assertions is applied independently at the same point in the subject
+string. First there is a check that the previous three characters are all
+digits, and then there is a check that the same three characters are not "999".
+This pattern does <i>not</i> match "foo" preceded by six characters, the first
+of which are digits and the last three of which are not "999". For example, it
+doesn't match "123abcfoo". A pattern to do that is
+<pre>
+  (?&#60;=\d{3}...)(?&#60;!999)foo
+</pre>
+This time the first assertion looks at the preceding six characters, checking
+that the first three are digits, and then the second assertion checks that the
+preceding three characters are not "999".
+</P>
+<P>
+Assertions can be nested in any combination. For example,
+<pre>
+  (?&#60;=(?&#60;!foo)bar)baz
+</pre>
+matches an occurrence of "baz" that is preceded by "bar" which in turn is not
+preceded by "foo", while
+<pre>
+  (?&#60;=\d{3}(?!999)...)foo
+</pre>
+is another pattern that matches "foo" preceded by three digits and any three
+characters that are not "999".
+<a name="conditions"></a></P>
+<br><a name="SEC21" href="#TOC1">CONDITIONAL SUBPATTERNS</a><br>
+<P>
+It is possible to cause the matching process to obey a subpattern
+conditionally or to choose between two alternative subpatterns, depending on
+the result of an assertion, or whether a specific capturing subpattern has
+already been matched. The two possible forms of conditional subpattern are:
+<pre>
+  (?(condition)yes-pattern)
+  (?(condition)yes-pattern|no-pattern)
+</pre>
+If the condition is satisfied, the yes-pattern is used; otherwise the
+no-pattern (if present) is used. If there are more than two alternatives in the
+subpattern, a compile-time error occurs. Each of the two alternatives may
+itself contain nested subpatterns of any form, including conditional
+subpatterns; the restriction to two alternatives applies only at the level of
+the condition. This pattern fragment is an example where the alternatives are
+complex:
+<pre>
+  (?(1) (A|B|C) | (D | (?(2)E|F) | E) )
+
+</PRE>
+</P>
+<P>
+There are four kinds of condition: references to subpatterns, references to
+recursion, a pseudo-condition called DEFINE, and assertions.
+</P>
+<br><b>
+Checking for a used subpattern by number
+</b><br>
+<P>
+If the text between the parentheses consists of a sequence of digits, the
+condition is true if a capturing subpattern of that number has previously
+matched. If there is more than one capturing subpattern with the same number
+(see the earlier
+<a href="#recursion">section about duplicate subpattern numbers),</a>
+the condition is true if any of them have matched. An alternative notation is
+to precede the digits with a plus or minus sign. In this case, the subpattern
+number is relative rather than absolute. The most recently opened parentheses
+can be referenced by (?(-1), the next most recent by (?(-2), and so on. Inside
+loops it can also make sense to refer to subsequent groups. The next
+parentheses to be opened can be referenced as (?(+1), and so on. (The value
+zero in any of these forms is not used; it provokes a compile-time error.)
+</P>
+<P>
+Consider the following pattern, which contains non-significant white space to
+make it more readable (assume the PCRE_EXTENDED option) and to divide it into
+three parts for ease of discussion:
+<pre>
+  ( \( )?    [^()]+    (?(1) \) )
+</pre>
+The first part matches an optional opening parenthesis, and if that
+character is present, sets it as the first captured substring. The second part
+matches one or more characters that are not parentheses. The third part is a
+conditional subpattern that tests whether or not the first set of parentheses
+matched. If they did, that is, if subject started with an opening parenthesis,
+the condition is true, and so the yes-pattern is executed and a closing
+parenthesis is required. Otherwise, since no-pattern is not present, the
+subpattern matches nothing. In other words, this pattern matches a sequence of
+non-parentheses, optionally enclosed in parentheses.
+</P>
+<P>
+If you were embedding this pattern in a larger one, you could use a relative
+reference:
+<pre>
+  ...other stuff... ( \( )?    [^()]+    (?(-1) \) ) ...
+</pre>
+This makes the fragment independent of the parentheses in the larger pattern.
+</P>
+<br><b>
+Checking for a used subpattern by name
+</b><br>
+<P>
+Perl uses the syntax (?(&#60;name&#62;)...) or (?('name')...) to test for a used
+subpattern by name. For compatibility with earlier versions of PCRE, which had
+this facility before Perl, the syntax (?(name)...) is also recognized.
+</P>
+<P>
+Rewriting the above example to use a named subpattern gives this:
+<pre>
+  (?&#60;OPEN&#62; \( )?    [^()]+    (?(&#60;OPEN&#62;) \) )
+</pre>
+If the name used in a condition of this kind is a duplicate, the test is
+applied to all subpatterns of the same name, and is true if any one of them has
+matched.
+</P>
+<br><b>
+Checking for pattern recursion
+</b><br>
+<P>
+If the condition is the string (R), and there is no subpattern with the name R,
+the condition is true if a recursive call to the whole pattern or any
+subpattern has been made. If digits or a name preceded by ampersand follow the
+letter R, for example:
+<pre>
+  (?(R3)...) or (?(R&name)...)
+</pre>
+the condition is true if the most recent recursion is into a subpattern whose
+number or name is given. This condition does not check the entire recursion
+stack. If the name used in a condition of this kind is a duplicate, the test is
+applied to all subpatterns of the same name, and is true if any one of them is
+the most recent recursion.
+</P>
+<P>
+At "top level", all these recursion test conditions are false.
+<a href="#recursion">The syntax for recursive patterns</a>
+is described below.
+<a name="subdefine"></a></P>
+<br><b>
+Defining subpatterns for use by reference only
+</b><br>
+<P>
+If the condition is the string (DEFINE), and there is no subpattern with the
+name DEFINE, the condition is always false. In this case, there may be only one
+alternative in the subpattern. It is always skipped if control reaches this
+point in the pattern; the idea of DEFINE is that it can be used to define
+subroutines that can be referenced from elsewhere. (The use of
+<a href="#subpatternsassubroutines">subroutines</a>
+is described below.) For example, a pattern to match an IPv4 address such as
+"192.168.23.245" could be written like this (ignore white space and line
+breaks):
+<pre>
+  (?(DEFINE) (?&#60;byte&#62; 2[0-4]\d | 25[0-5] | 1\d\d | [1-9]?\d) )
+  \b (?&byte) (\.(?&byte)){3} \b
+</pre>
+The first part of the pattern is a DEFINE group inside which a another group
+named "byte" is defined. This matches an individual component of an IPv4
+address (a number less than 256). When matching takes place, this part of the
+pattern is skipped because DEFINE acts like a false condition. The rest of the
+pattern uses references to the named group to match the four dot-separated
+components of an IPv4 address, insisting on a word boundary at each end.
+</P>
+<br><b>
+Assertion conditions
+</b><br>
+<P>
+If the condition is not in any of the above formats, it must be an assertion.
+This may be a positive or negative lookahead or lookbehind assertion. Consider
+this pattern, again containing non-significant white space, and with the two
+alternatives on the second line:
+<pre>
+  (?(?=[^a-z]*[a-z])
+  \d{2}-[a-z]{3}-\d{2}  |  \d{2}-\d{2}-\d{2} )
+</pre>
+The condition is a positive lookahead assertion that matches an optional
+sequence of non-letters followed by a letter. In other words, it tests for the
+presence of at least one letter in the subject. If a letter is found, the
+subject is matched against the first alternative; otherwise it is matched
+against the second. This pattern matches strings in one of the two forms
+dd-aaa-dd or dd-dd-dd, where aaa are letters and dd are digits.
+<a name="comments"></a></P>
+<br><a name="SEC22" href="#TOC1">COMMENTS</a><br>
+<P>
+There are two ways of including comments in patterns that are processed by
+PCRE. In both cases, the start of the comment must not be in a character class,
+nor in the middle of any other sequence of related characters such as (?: or a
+subpattern name or number. The characters that make up a comment play no part
+in the pattern matching.
+</P>
+<P>
+The sequence (?# marks the start of a comment that continues up to the next
+closing parenthesis. Nested parentheses are not permitted. If the PCRE_EXTENDED
+option is set, an unescaped # character also introduces a comment, which in
+this case continues to immediately after the next newline character or
+character sequence in the pattern. Which characters are interpreted as newlines
+is controlled by the options passed to a compiling function or by a special
+sequence at the start of the pattern, as described in the section entitled
+<a href="#newlines">"Newline conventions"</a>
+above. Note that the end of this type of comment is a literal newline sequence
+in the pattern; escape sequences that happen to represent a newline do not
+count. For example, consider this pattern when PCRE_EXTENDED is set, and the
+default newline convention is in force:
+<pre>
+  abc #comment \n still comment
+</pre>
+On encountering the # character, <b>pcre_compile()</b> skips along, looking for
+a newline in the pattern. The sequence \n is still literal at this stage, so
+it does not terminate the comment. Only an actual character with the code value
+0x0a (the default newline) does so.
+<a name="recursion"></a></P>
+<br><a name="SEC23" href="#TOC1">RECURSIVE PATTERNS</a><br>
+<P>
+Consider the problem of matching a string in parentheses, allowing for
+unlimited nested parentheses. Without the use of recursion, the best that can
+be done is to use a pattern that matches up to some fixed depth of nesting. It
+is not possible to handle an arbitrary nesting depth.
+</P>
+<P>
+For some time, Perl has provided a facility that allows regular expressions to
+recurse (amongst other things). It does this by interpolating Perl code in the
+expression at run time, and the code can refer to the expression itself. A Perl
+pattern using code interpolation to solve the parentheses problem can be
+created like this:
+<pre>
+  $re = qr{\( (?: (?&#62;[^()]+) | (?p{$re}) )* \)}x;
+</pre>
+The (?p{...}) item interpolates Perl code at run time, and in this case refers
+recursively to the pattern in which it appears.
+</P>
+<P>
+Obviously, PCRE cannot support the interpolation of Perl code. Instead, it
+supports special syntax for recursion of the entire pattern, and also for
+individual subpattern recursion. After its introduction in PCRE and Python,
+this kind of recursion was subsequently introduced into Perl at release 5.10.
+</P>
+<P>
+A special item that consists of (? followed by a number greater than zero and a
+closing parenthesis is a recursive subroutine call of the subpattern of the
+given number, provided that it occurs inside that subpattern. (If not, it is a
+<a href="#subpatternsassubroutines">non-recursive subroutine</a>
+call, which is described in the next section.) The special item (?R) or (?0) is
+a recursive call of the entire regular expression.
+</P>
+<P>
+This PCRE pattern solves the nested parentheses problem (assume the
+PCRE_EXTENDED option is set so that white space is ignored):
+<pre>
+  \( ( [^()]++ | (?R) )* \)
+</pre>
+First it matches an opening parenthesis. Then it matches any number of
+substrings which can either be a sequence of non-parentheses, or a recursive
+match of the pattern itself (that is, a correctly parenthesized substring).
+Finally there is a closing parenthesis. Note the use of a possessive quantifier
+to avoid backtracking into sequences of non-parentheses.
+</P>
+<P>
+If this were part of a larger pattern, you would not want to recurse the entire
+pattern, so instead you could use this:
+<pre>
+  ( \( ( [^()]++ | (?1) )* \) )
+</pre>
+We have put the pattern into parentheses, and caused the recursion to refer to
+them instead of the whole pattern.
+</P>
+<P>
+In a larger pattern, keeping track of parenthesis numbers can be tricky. This
+is made easier by the use of relative references. Instead of (?1) in the
+pattern above you can write (?-2) to refer to the second most recently opened
+parentheses preceding the recursion. In other words, a negative number counts
+capturing parentheses leftwards from the point at which it is encountered.
+</P>
+<P>
+It is also possible to refer to subsequently opened parentheses, by writing
+references such as (?+2). However, these cannot be recursive because the
+reference is not inside the parentheses that are referenced. They are always
+<a href="#subpatternsassubroutines">non-recursive subroutine</a>
+calls, as described in the next section.
+</P>
+<P>
+An alternative approach is to use named parentheses instead. The Perl syntax
+for this is (?&name); PCRE's earlier syntax (?P&#62;name) is also supported. We
+could rewrite the above example as follows:
+<pre>
+  (?&#60;pn&#62; \( ( [^()]++ | (?&pn) )* \) )
+</pre>
+If there is more than one subpattern with the same name, the earliest one is
+used.
+</P>
+<P>
+This particular example pattern that we have been looking at contains nested
+unlimited repeats, and so the use of a possessive quantifier for matching
+strings of non-parentheses is important when applying the pattern to strings
+that do not match. For example, when this pattern is applied to
+<pre>
+  (aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa()
+</pre>
+it yields "no match" quickly. However, if a possessive quantifier is not used,
+the match runs for a very long time indeed because there are so many different
+ways the + and * repeats can carve up the subject, and all have to be tested
+before failure can be reported.
+</P>
+<P>
+At the end of a match, the values of capturing parentheses are those from
+the outermost level. If you want to obtain intermediate values, a callout
+function can be used (see below and the
+<a href="pcrecallout.html"><b>pcrecallout</b></a>
+documentation). If the pattern above is matched against
+<pre>
+  (ab(cd)ef)
+</pre>
+the value for the inner capturing parentheses (numbered 2) is "ef", which is
+the last value taken on at the top level. If a capturing subpattern is not
+matched at the top level, its final captured value is unset, even if it was
+(temporarily) set at a deeper level during the matching process.
+</P>
+<P>
+If there are more than 15 capturing parentheses in a pattern, PCRE has to
+obtain extra memory to store data during a recursion, which it does by using
+<b>pcre_malloc</b>, freeing it via <b>pcre_free</b> afterwards. If no memory can
+be obtained, the match fails with the PCRE_ERROR_NOMEMORY error.
+</P>
+<P>
+Do not confuse the (?R) item with the condition (R), which tests for recursion.
+Consider this pattern, which matches text in angle brackets, allowing for
+arbitrary nesting. Only digits are allowed in nested brackets (that is, when
+recursing), whereas any characters are permitted at the outer level.
+<pre>
+  &#60; (?: (?(R) \d++  | [^&#60;&#62;]*+) | (?R)) * &#62;
+</pre>
+In this pattern, (?(R) is the start of a conditional subpattern, with two
+different alternatives for the recursive and non-recursive cases. The (?R) item
+is the actual recursive call.
+<a name="recursiondifference"></a></P>
+<br><b>
+Differences in recursion processing between PCRE and Perl
+</b><br>
+<P>
+Recursion processing in PCRE differs from Perl in two important ways. In PCRE
+(like Python, but unlike Perl), a recursive subpattern call is always treated
+as an atomic group. That is, once it has matched some of the subject string, it
+is never re-entered, even if it contains untried alternatives and there is a
+subsequent matching failure. This can be illustrated by the following pattern,
+which purports to match a palindromic string that contains an odd number of
+characters (for example, "a", "aba", "abcba", "abcdcba"):
+<pre>
+  ^(.|(.)(?1)\2)$
+</pre>
+The idea is that it either matches a single character, or two identical
+characters surrounding a sub-palindrome. In Perl, this pattern works; in PCRE
+it does not if the pattern is longer than three characters. Consider the
+subject string "abcba":
+</P>
+<P>
+At the top level, the first character is matched, but as it is not at the end
+of the string, the first alternative fails; the second alternative is taken
+and the recursion kicks in. The recursive call to subpattern 1 successfully
+matches the next character ("b"). (Note that the beginning and end of line
+tests are not part of the recursion).
+</P>
+<P>
+Back at the top level, the next character ("c") is compared with what
+subpattern 2 matched, which was "a". This fails. Because the recursion is
+treated as an atomic group, there are now no backtracking points, and so the
+entire match fails. (Perl is able, at this point, to re-enter the recursion and
+try the second alternative.) However, if the pattern is written with the
+alternatives in the other order, things are different:
+<pre>
+  ^((.)(?1)\2|.)$
+</pre>
+This time, the recursing alternative is tried first, and continues to recurse
+until it runs out of characters, at which point the recursion fails. But this
+time we do have another alternative to try at the higher level. That is the big
+difference: in the previous case the remaining alternative is at a deeper
+recursion level, which PCRE cannot use.
+</P>
+<P>
+To change the pattern so that it matches all palindromic strings, not just
+those with an odd number of characters, it is tempting to change the pattern to
+this:
+<pre>
+  ^((.)(?1)\2|.?)$
+</pre>
+Again, this works in Perl, but not in PCRE, and for the same reason. When a
+deeper recursion has matched a single character, it cannot be entered again in
+order to match an empty string. The solution is to separate the two cases, and
+write out the odd and even cases as alternatives at the higher level:
+<pre>
+  ^(?:((.)(?1)\2|)|((.)(?3)\4|.))
+</pre>
+If you want to match typical palindromic phrases, the pattern has to ignore all
+non-word characters, which can be done like this:
+<pre>
+  ^\W*+(?:((.)\W*+(?1)\W*+\2|)|((.)\W*+(?3)\W*+\4|\W*+.\W*+))\W*+$
+</pre>
+If run with the PCRE_CASELESS option, this pattern matches phrases such as "A
+man, a plan, a canal: Panama!" and it works well in both PCRE and Perl. Note
+the use of the possessive quantifier *+ to avoid backtracking into sequences of
+non-word characters. Without this, PCRE takes a great deal longer (ten times or
+more) to match typical phrases, and Perl takes so long that you think it has
+gone into a loop.
+</P>
+<P>
+<b>WARNING</b>: The palindrome-matching patterns above work only if the subject
+string does not start with a palindrome that is shorter than the entire string.
+For example, although "abcba" is correctly matched, if the subject is "ababa",
+PCRE finds the palindrome "aba" at the start, then fails at top level because
+the end of the string does not follow. Once again, it cannot jump back into the
+recursion to try other alternatives, so the entire match fails.
+</P>
+<P>
+The second way in which PCRE and Perl differ in their recursion processing is
+in the handling of captured values. In Perl, when a subpattern is called
+recursively or as a subpattern (see the next section), it has no access to any
+values that were captured outside the recursion, whereas in PCRE these values
+can be referenced. Consider this pattern:
+<pre>
+  ^(.)(\1|a(?2))
+</pre>
+In PCRE, this pattern matches "bab". The first capturing parentheses match "b",
+then in the second group, when the back reference \1 fails to match "b", the
+second alternative matches "a" and then recurses. In the recursion, \1 does
+now match "b" and so the whole match succeeds. In Perl, the pattern fails to
+match because inside the recursive call \1 cannot access the externally set
+value.
+<a name="subpatternsassubroutines"></a></P>
+<br><a name="SEC24" href="#TOC1">SUBPATTERNS AS SUBROUTINES</a><br>
+<P>
+If the syntax for a recursive subpattern call (either by number or by
+name) is used outside the parentheses to which it refers, it operates like a
+subroutine in a programming language. The called subpattern may be defined
+before or after the reference. A numbered reference can be absolute or
+relative, as in these examples:
+<pre>
+  (...(absolute)...)...(?2)...
+  (...(relative)...)...(?-1)...
+  (...(?+1)...(relative)...
+</pre>
+An earlier example pointed out that the pattern
+<pre>
+  (sens|respons)e and \1ibility
+</pre>
+matches "sense and sensibility" and "response and responsibility", but not
+"sense and responsibility". If instead the pattern
+<pre>
+  (sens|respons)e and (?1)ibility
+</pre>
+is used, it does match "sense and responsibility" as well as the other two
+strings. Another example is given in the discussion of DEFINE above.
+</P>
+<P>
+All subroutine calls, whether recursive or not, are always treated as atomic
+groups. That is, once a subroutine has matched some of the subject string, it
+is never re-entered, even if it contains untried alternatives and there is a
+subsequent matching failure. Any capturing parentheses that are set during the
+subroutine call revert to their previous values afterwards.
+</P>
+<P>
+Processing options such as case-independence are fixed when a subpattern is
+defined, so if it is used as a subroutine, such options cannot be changed for
+different calls. For example, consider this pattern:
+<pre>
+  (abc)(?i:(?-1))
+</pre>
+It matches "abcabc". It does not match "abcABC" because the change of
+processing option does not affect the called subpattern.
+<a name="onigurumasubroutines"></a></P>
+<br><a name="SEC25" href="#TOC1">ONIGURUMA SUBROUTINE SYNTAX</a><br>
+<P>
+For compatibility with Oniguruma, the non-Perl syntax \g followed by a name or
+a number enclosed either in angle brackets or single quotes, is an alternative
+syntax for referencing a subpattern as a subroutine, possibly recursively. Here
+are two of the examples used above, rewritten using this syntax:
+<pre>
+  (?&#60;pn&#62; \( ( (?&#62;[^()]+) | \g&#60;pn&#62; )* \) )
+  (sens|respons)e and \g'1'ibility
+</pre>
+PCRE supports an extension to Oniguruma: if a number is preceded by a
+plus or a minus sign it is taken as a relative reference. For example:
+<pre>
+  (abc)(?i:\g&#60;-1&#62;)
+</pre>
+Note that \g{...} (Perl syntax) and \g&#60;...&#62; (Oniguruma syntax) are <i>not</i>
+synonymous. The former is a back reference; the latter is a subroutine call.
+</P>
+<br><a name="SEC26" href="#TOC1">CALLOUTS</a><br>
+<P>
+Perl has a feature whereby using the sequence (?{...}) causes arbitrary Perl
+code to be obeyed in the middle of matching a regular expression. This makes it
+possible, amongst other things, to extract different substrings that match the
+same pair of parentheses when there is a repetition.
+</P>
+<P>
+PCRE provides a similar feature, but of course it cannot obey arbitrary Perl
+code. The feature is called "callout". The caller of PCRE provides an external
+function by putting its entry point in the global variable <i>pcre_callout</i>
+(8-bit library) or <i>pcre[16|32]_callout</i> (16-bit or 32-bit library).
+By default, this variable contains NULL, which disables all calling out.
+</P>
+<P>
+Within a regular expression, (?C) indicates the points at which the external
+function is to be called. If you want to identify different callout points, you
+can put a number less than 256 after the letter C. The default value is zero.
+For example, this pattern has two callout points:
+<pre>
+  (?C1)abc(?C2)def
+</pre>
+If the PCRE_AUTO_CALLOUT flag is passed to a compiling function, callouts are
+automatically installed before each item in the pattern. They are all numbered
+255. If there is a conditional group in the pattern whose condition is an
+assertion, an additional callout is inserted just before the condition. An
+explicit callout may also be set at this position, as in this example:
+<pre>
+  (?(?C9)(?=a)abc|def)
+</pre>
+Note that this applies only to assertion conditions, not to other types of
+condition.
+</P>
+<P>
+During matching, when PCRE reaches a callout point, the external function is
+called. It is provided with the number of the callout, the position in the
+pattern, and, optionally, one item of data originally supplied by the caller of
+the matching function. The callout function may cause matching to proceed, to
+backtrack, or to fail altogether.
+</P>
+<P>
+By default, PCRE implements a number of optimizations at compile time and
+matching time, and one side-effect is that sometimes callouts are skipped. If
+you need all possible callouts to happen, you need to set options that disable
+the relevant optimizations. More details, and a complete description of the
+interface to the callout function, are given in the
+<a href="pcrecallout.html"><b>pcrecallout</b></a>
+documentation.
+<a name="backtrackcontrol"></a></P>
+<br><a name="SEC27" href="#TOC1">BACKTRACKING CONTROL</a><br>
+<P>
+Perl 5.10 introduced a number of "Special Backtracking Control Verbs", which
+are still described in the Perl documentation as "experimental and subject to
+change or removal in a future version of Perl". It goes on to say: "Their usage
+in production code should be noted to avoid problems during upgrades." The same
+remarks apply to the PCRE features described in this section.
+</P>
+<P>
+The new verbs make use of what was previously invalid syntax: an opening
+parenthesis followed by an asterisk. They are generally of the form
+(*VERB) or (*VERB:NAME). Some may take either form, possibly behaving
+differently depending on whether or not a name is present. A name is any
+sequence of characters that does not include a closing parenthesis. The maximum
+length of name is 255 in the 8-bit library and 65535 in the 16-bit and 32-bit
+libraries. If the name is empty, that is, if the closing parenthesis
+immediately follows the colon, the effect is as if the colon were not there.
+Any number of these verbs may occur in a pattern.
+</P>
+<P>
+Since these verbs are specifically related to backtracking, most of them can be
+used only when the pattern is to be matched using one of the traditional
+matching functions, because these use a backtracking algorithm. With the
+exception of (*FAIL), which behaves like a failing negative assertion, the
+backtracking control verbs cause an error if encountered by a DFA matching
+function.
+</P>
+<P>
+The behaviour of these verbs in
+<a href="#btrepeat">repeated groups,</a>
+<a href="#btassert">assertions,</a>
+and in
+<a href="#btsub">subpatterns called as subroutines</a>
+(whether or not recursively) is documented below.
+<a name="nooptimize"></a></P>
+<br><b>
+Optimizations that affect backtracking verbs
+</b><br>
+<P>
+PCRE contains some optimizations that are used to speed up matching by running
+some checks at the start of each match attempt. For example, it may know the
+minimum length of matching subject, or that a particular character must be
+present. When one of these optimizations bypasses the running of a match, any
+included backtracking verbs will not, of course, be processed. You can suppress
+the start-of-match optimizations by setting the PCRE_NO_START_OPTIMIZE option
+when calling <b>pcre_compile()</b> or <b>pcre_exec()</b>, or by starting the
+pattern with (*NO_START_OPT). There is more discussion of this option in the
+section entitled
+<a href="pcreapi.html#execoptions">"Option bits for <b>pcre_exec()</b>"</a>
+in the
+<a href="pcreapi.html"><b>pcreapi</b></a>
+documentation.
+</P>
+<P>
+Experiments with Perl suggest that it too has similar optimizations, sometimes
+leading to anomalous results.
+</P>
+<br><b>
+Verbs that act immediately
+</b><br>
+<P>
+The following verbs act as soon as they are encountered. They may not be
+followed by a name.
+<pre>
+   (*ACCEPT)
+</pre>
+This verb causes the match to end successfully, skipping the remainder of the
+pattern. However, when it is inside a subpattern that is called as a
+subroutine, only that subpattern is ended successfully. Matching then continues
+at the outer level. If (*ACCEPT) in triggered in a positive assertion, the
+assertion succeeds; in a negative assertion, the assertion fails.
+</P>
+<P>
+If (*ACCEPT) is inside capturing parentheses, the data so far is captured. For
+example:
+<pre>
+  A((?:A|B(*ACCEPT)|C)D)
+</pre>
+This matches "AB", "AAD", or "ACD"; when it matches "AB", "B" is captured by
+the outer parentheses.
+<pre>
+  (*FAIL) or (*F)
+</pre>
+This verb causes a matching failure, forcing backtracking to occur. It is
+equivalent to (?!) but easier to read. The Perl documentation notes that it is
+probably useful only when combined with (?{}) or (??{}). Those are, of course,
+Perl features that are not present in PCRE. The nearest equivalent is the
+callout feature, as for example in this pattern:
+<pre>
+  a+(?C)(*FAIL)
+</pre>
+A match with the string "aaaa" always fails, but the callout is taken before
+each backtrack happens (in this example, 10 times).
+</P>
+<br><b>
+Recording which path was taken
+</b><br>
+<P>
+There is one verb whose main purpose is to track how a match was arrived at,
+though it also has a secondary use in conjunction with advancing the match
+starting point (see (*SKIP) below).
+<pre>
+  (*MARK:NAME) or (*:NAME)
+</pre>
+A name is always required with this verb. There may be as many instances of
+(*MARK) as you like in a pattern, and their names do not have to be unique.
+</P>
+<P>
+When a match succeeds, the name of the last-encountered (*MARK:NAME),
+(*PRUNE:NAME), or (*THEN:NAME) on the matching path is passed back to the
+caller as described in the section entitled
+<a href="pcreapi.html#extradata">"Extra data for <b>pcre_exec()</b>"</a>
+in the
+<a href="pcreapi.html"><b>pcreapi</b></a>
+documentation. Here is an example of <b>pcretest</b> output, where the /K
+modifier requests the retrieval and outputting of (*MARK) data:
+<pre>
+    re&#62; /X(*MARK:A)Y|X(*MARK:B)Z/K
+  data&#62; XY
+   0: XY
+  MK: A
+  XZ
+   0: XZ
+  MK: B
+</pre>
+The (*MARK) name is tagged with "MK:" in this output, and in this example it
+indicates which of the two alternatives matched. This is a more efficient way
+of obtaining this information than putting each alternative in its own
+capturing parentheses.
+</P>
+<P>
+If a verb with a name is encountered in a positive assertion that is true, the
+name is recorded and passed back if it is the last-encountered. This does not
+happen for negative assertions or failing positive assertions.
+</P>
+<P>
+After a partial match or a failed match, the last encountered name in the
+entire match process is returned. For example:
+<pre>
+    re&#62; /X(*MARK:A)Y|X(*MARK:B)Z/K
+  data&#62; XP
+  No match, mark = B
+</pre>
+Note that in this unanchored example the mark is retained from the match
+attempt that started at the letter "X" in the subject. Subsequent match
+attempts starting at "P" and then with an empty string do not get as far as the
+(*MARK) item, but nevertheless do not reset it.
+</P>
+<P>
+If you are interested in (*MARK) values after failed matches, you should
+probably set the PCRE_NO_START_OPTIMIZE option
+<a href="#nooptimize">(see above)</a>
+to ensure that the match is always attempted.
+</P>
+<br><b>
+Verbs that act after backtracking
+</b><br>
+<P>
+The following verbs do nothing when they are encountered. Matching continues
+with what follows, but if there is no subsequent match, causing a backtrack to
+the verb, a failure is forced. That is, backtracking cannot pass to the left of
+the verb. However, when one of these verbs appears inside an atomic group or an
+assertion that is true, its effect is confined to that group, because once the
+group has been matched, there is never any backtracking into it. In this
+situation, backtracking can "jump back" to the left of the entire atomic group
+or assertion. (Remember also, as stated above, that this localization also
+applies in subroutine calls.)
+</P>
+<P>
+These verbs differ in exactly what kind of failure occurs when backtracking
+reaches them. The behaviour described below is what happens when the verb is
+not in a subroutine or an assertion. Subsequent sections cover these special
+cases.
+<pre>
+  (*COMMIT)
+</pre>
+This verb, which may not be followed by a name, causes the whole match to fail
+outright if there is a later matching failure that causes backtracking to reach
+it. Even if the pattern is unanchored, no further attempts to find a match by
+advancing the starting point take place. If (*COMMIT) is the only backtracking
+verb that is encountered, once it has been passed <b>pcre_exec()</b> is
+committed to finding a match at the current starting point, or not at all. For
+example:
+<pre>
+  a+(*COMMIT)b
+</pre>
+This matches "xxaab" but not "aacaab". It can be thought of as a kind of
+dynamic anchor, or "I've started, so I must finish." The name of the most
+recently passed (*MARK) in the path is passed back when (*COMMIT) forces a
+match failure.
+</P>
+<P>
+If there is more than one backtracking verb in a pattern, a different one that
+follows (*COMMIT) may be triggered first, so merely passing (*COMMIT) during a
+match does not always guarantee that a match must be at this starting point.
+</P>
+<P>
+Note that (*COMMIT) at the start of a pattern is not the same as an anchor,
+unless PCRE's start-of-match optimizations are turned off, as shown in this
+output from <b>pcretest</b>:
+<pre>
+    re&#62; /(*COMMIT)abc/
+  data&#62; xyzabc
+   0: abc
+  data&#62; xyzabc\Y
+  No match
+</pre>
+For this pattern, PCRE knows that any match must start with "a", so the
+optimization skips along the subject to "a" before applying the pattern to the
+first set of data. The match attempt then succeeds. In the second set of data,
+the escape sequence \Y is interpreted by the <b>pcretest</b> program. It causes
+the PCRE_NO_START_OPTIMIZE option to be set when <b>pcre_exec()</b> is called.
+This disables the optimization that skips along to the first character. The
+pattern is now applied starting at "x", and so the (*COMMIT) causes the match
+to fail without trying any other starting points.
+<pre>
+  (*PRUNE) or (*PRUNE:NAME)
+</pre>
+This verb causes the match to fail at the current starting position in the
+subject if there is a later matching failure that causes backtracking to reach
+it. If the pattern is unanchored, the normal "bumpalong" advance to the next
+starting character then happens. Backtracking can occur as usual to the left of
+(*PRUNE), before it is reached, or when matching to the right of (*PRUNE), but
+if there is no match to the right, backtracking cannot cross (*PRUNE). In
+simple cases, the use of (*PRUNE) is just an alternative to an atomic group or
+possessive quantifier, but there are some uses of (*PRUNE) that cannot be
+expressed in any other way. In an anchored pattern (*PRUNE) has the same effect
+as (*COMMIT).
+</P>
+<P>
+The behaviour of (*PRUNE:NAME) is the not the same as (*MARK:NAME)(*PRUNE).
+It is like (*MARK:NAME) in that the name is remembered for passing back to the
+caller. However, (*SKIP:NAME) searches only for names set with (*MARK).
+<pre>
+  (*SKIP)
+</pre>
+This verb, when given without a name, is like (*PRUNE), except that if the
+pattern is unanchored, the "bumpalong" advance is not to the next character,
+but to the position in the subject where (*SKIP) was encountered. (*SKIP)
+signifies that whatever text was matched leading up to it cannot be part of a
+successful match. Consider:
+<pre>
+  a+(*SKIP)b
+</pre>
+If the subject is "aaaac...", after the first match attempt fails (starting at
+the first character in the string), the starting point skips on to start the
+next attempt at "c". Note that a possessive quantifer does not have the same
+effect as this example; although it would suppress backtracking during the
+first match attempt, the second attempt would start at the second character
+instead of skipping on to "c".
+<pre>
+  (*SKIP:NAME)
+</pre>
+When (*SKIP) has an associated name, its behaviour is modified. When it is
+triggered, the previous path through the pattern is searched for the most
+recent (*MARK) that has the same name. If one is found, the "bumpalong" advance
+is to the subject position that corresponds to that (*MARK) instead of to where
+(*SKIP) was encountered. If no (*MARK) with a matching name is found, the
+(*SKIP) is ignored.
+</P>
+<P>
+Note that (*SKIP:NAME) searches only for names set by (*MARK:NAME). It ignores
+names that are set by (*PRUNE:NAME) or (*THEN:NAME).
+<pre>
+  (*THEN) or (*THEN:NAME)
+</pre>
+This verb causes a skip to the next innermost alternative when backtracking
+reaches it. That is, it cancels any further backtracking within the current
+alternative. Its name comes from the observation that it can be used for a
+pattern-based if-then-else block:
+<pre>
+  ( COND1 (*THEN) FOO | COND2 (*THEN) BAR | COND3 (*THEN) BAZ ) ...
+</pre>
+If the COND1 pattern matches, FOO is tried (and possibly further items after
+the end of the group if FOO succeeds); on failure, the matcher skips to the
+second alternative and tries COND2, without backtracking into COND1. If that
+succeeds and BAR fails, COND3 is tried. If subsequently BAZ fails, there are no
+more alternatives, so there is a backtrack to whatever came before the entire
+group. If (*THEN) is not inside an alternation, it acts like (*PRUNE).
+</P>
+<P>
+The behaviour of (*THEN:NAME) is the not the same as (*MARK:NAME)(*THEN).
+It is like (*MARK:NAME) in that the name is remembered for passing back to the
+caller. However, (*SKIP:NAME) searches only for names set with (*MARK).
+</P>
+<P>
+A subpattern that does not contain a | character is just a part of the
+enclosing alternative; it is not a nested alternation with only one
+alternative. The effect of (*THEN) extends beyond such a subpattern to the
+enclosing alternative. Consider this pattern, where A, B, etc. are complex
+pattern fragments that do not contain any | characters at this level:
+<pre>
+  A (B(*THEN)C) | D
+</pre>
+If A and B are matched, but there is a failure in C, matching does not
+backtrack into A; instead it moves to the next alternative, that is, D.
+However, if the subpattern containing (*THEN) is given an alternative, it
+behaves differently:
+<pre>
+  A (B(*THEN)C | (*FAIL)) | D
+</pre>
+The effect of (*THEN) is now confined to the inner subpattern. After a failure
+in C, matching moves to (*FAIL), which causes the whole subpattern to fail
+because there are no more alternatives to try. In this case, matching does now
+backtrack into A.
+</P>
+<P>
+Note that a conditional subpattern is not considered as having two
+alternatives, because only one is ever used. In other words, the | character in
+a conditional subpattern has a different meaning. Ignoring white space,
+consider:
+<pre>
+  ^.*? (?(?=a) a | b(*THEN)c )
+</pre>
+If the subject is "ba", this pattern does not match. Because .*? is ungreedy,
+it initially matches zero characters. The condition (?=a) then fails, the
+character "b" is matched, but "c" is not. At this point, matching does not
+backtrack to .*? as might perhaps be expected from the presence of the |
+character. The conditional subpattern is part of the single alternative that
+comprises the whole pattern, and so the match fails. (If there was a backtrack
+into .*?, allowing it to match "b", the match would succeed.)
+</P>
+<P>
+The verbs just described provide four different "strengths" of control when
+subsequent matching fails. (*THEN) is the weakest, carrying on the match at the
+next alternative. (*PRUNE) comes next, failing the match at the current
+starting position, but allowing an advance to the next character (for an
+unanchored pattern). (*SKIP) is similar, except that the advance may be more
+than one character. (*COMMIT) is the strongest, causing the entire match to
+fail.
+</P>
+<br><b>
+More than one backtracking verb
+</b><br>
+<P>
+If more than one backtracking verb is present in a pattern, the one that is
+backtracked onto first acts. For example, consider this pattern, where A, B,
+etc. are complex pattern fragments:
+<pre>
+  (A(*COMMIT)B(*THEN)C|ABD)
+</pre>
+If A matches but B fails, the backtrack to (*COMMIT) causes the entire match to
+fail. However, if A and B match, but C fails, the backtrack to (*THEN) causes
+the next alternative (ABD) to be tried. This behaviour is consistent, but is
+not always the same as Perl's. It means that if two or more backtracking verbs
+appear in succession, all the the last of them has no effect. Consider this
+example:
+<pre>
+  ...(*COMMIT)(*PRUNE)...
+</pre>
+If there is a matching failure to the right, backtracking onto (*PRUNE) causes
+it to be triggered, and its action is taken. There can never be a backtrack
+onto (*COMMIT).
+<a name="btrepeat"></a></P>
+<br><b>
+Backtracking verbs in repeated groups
+</b><br>
+<P>
+PCRE differs from Perl in its handling of backtracking verbs in repeated
+groups. For example, consider:
+<pre>
+  /(a(*COMMIT)b)+ac/
+</pre>
+If the subject is "abac", Perl matches, but PCRE fails because the (*COMMIT) in
+the second repeat of the group acts.
+<a name="btassert"></a></P>
+<br><b>
+Backtracking verbs in assertions
+</b><br>
+<P>
+(*FAIL) in an assertion has its normal effect: it forces an immediate backtrack.
+</P>
+<P>
+(*ACCEPT) in a positive assertion causes the assertion to succeed without any
+further processing. In a negative assertion, (*ACCEPT) causes the assertion to
+fail without any further processing.
+</P>
+<P>
+The other backtracking verbs are not treated specially if they appear in a
+positive assertion. In particular, (*THEN) skips to the next alternative in the
+innermost enclosing group that has alternations, whether or not this is within
+the assertion.
+</P>
+<P>
+Negative assertions are, however, different, in order to ensure that changing a
+positive assertion into a negative assertion changes its result. Backtracking
+into (*COMMIT), (*SKIP), or (*PRUNE) causes a negative assertion to be true,
+without considering any further alternative branches in the assertion.
+Backtracking into (*THEN) causes it to skip to the next enclosing alternative
+within the assertion (the normal behaviour), but if the assertion does not have
+such an alternative, (*THEN) behaves like (*PRUNE).
+<a name="btsub"></a></P>
+<br><b>
+Backtracking verbs in subroutines
+</b><br>
+<P>
+These behaviours occur whether or not the subpattern is called recursively.
+Perl's treatment of subroutines is different in some cases.
+</P>
+<P>
+(*FAIL) in a subpattern called as a subroutine has its normal effect: it forces
+an immediate backtrack.
+</P>
+<P>
+(*ACCEPT) in a subpattern called as a subroutine causes the subroutine match to
+succeed without any further processing. Matching then continues after the
+subroutine call.
+</P>
+<P>
+(*COMMIT), (*SKIP), and (*PRUNE) in a subpattern called as a subroutine cause
+the subroutine match to fail.
+</P>
+<P>
+(*THEN) skips to the next alternative in the innermost enclosing group within
+the subpattern that has alternatives. If there is no such group within the
+subpattern, (*THEN) causes the subroutine match to fail.
+</P>
+<br><a name="SEC28" href="#TOC1">SEE ALSO</a><br>
+<P>
+<b>pcreapi</b>(3), <b>pcrecallout</b>(3), <b>pcrematching</b>(3),
+<b>pcresyntax</b>(3), <b>pcre</b>(3), <b>pcre16(3)</b>, <b>pcre32(3)</b>.
+</P>
+<br><a name="SEC29" href="#TOC1">AUTHOR</a><br>
+<P>
+Philip Hazel
+<br>
+University Computing Service
+<br>
+Cambridge CB2 3QH, England.
+<br>
+</P>
+<br><a name="SEC30" href="#TOC1">REVISION</a><br>
+<P>
+Last updated: 08 January 2014
+<br>
+Copyright &copy; 1997-2014 University of Cambridge.
+<br>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcreperform.html b/libs/Pcre16/docs/doc/html/pcreperform.html
new file mode 100644
index 0000000000..dda207f901
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcreperform.html
@@ -0,0 +1,195 @@
+<html>
+<head>
+<title>pcreperform specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcreperform man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<br><b>
+PCRE PERFORMANCE
+</b><br>
+<P>
+Two aspects of performance are discussed below: memory usage and processing
+time. The way you express your pattern as a regular expression can affect both
+of them.
+</P>
+<br><b>
+COMPILED PATTERN MEMORY USAGE
+</b><br>
+<P>
+Patterns are compiled by PCRE into a reasonably efficient interpretive code, so
+that most simple patterns do not use much memory. However, there is one case
+where the memory usage of a compiled pattern can be unexpectedly large. If a
+parenthesized subpattern has a quantifier with a minimum greater than 1 and/or
+a limited maximum, the whole subpattern is repeated in the compiled code. For
+example, the pattern
+<pre>
+  (abc|def){2,4}
+</pre>
+is compiled as if it were
+<pre>
+  (abc|def)(abc|def)((abc|def)(abc|def)?)?
+</pre>
+(Technical aside: It is done this way so that backtrack points within each of
+the repetitions can be independently maintained.)
+</P>
+<P>
+For regular expressions whose quantifiers use only small numbers, this is not
+usually a problem. However, if the numbers are large, and particularly if such
+repetitions are nested, the memory usage can become an embarrassment. For
+example, the very simple pattern
+<pre>
+  ((ab){1,1000}c){1,3}
+</pre>
+uses 51K bytes when compiled using the 8-bit library. When PCRE is compiled
+with its default internal pointer size of two bytes, the size limit on a
+compiled pattern is 64K data units, and this is reached with the above pattern
+if the outer repetition is increased from 3 to 4. PCRE can be compiled to use
+larger internal pointers and thus handle larger compiled patterns, but it is
+better to try to rewrite your pattern to use less memory if you can.
+</P>
+<P>
+One way of reducing the memory usage for such patterns is to make use of PCRE's
+<a href="pcrepattern.html#subpatternsassubroutines">"subroutine"</a>
+facility. Re-writing the above pattern as
+<pre>
+  ((ab)(?2){0,999}c)(?1){0,2}
+</pre>
+reduces the memory requirements to 18K, and indeed it remains under 20K even
+with the outer repetition increased to 100. However, this pattern is not
+exactly equivalent, because the "subroutine" calls are treated as
+<a href="pcrepattern.html#atomicgroup">atomic groups</a>
+into which there can be no backtracking if there is a subsequent matching
+failure. Therefore, PCRE cannot do this kind of rewriting automatically.
+Furthermore, there is a noticeable loss of speed when executing the modified
+pattern. Nevertheless, if the atomic grouping is not a problem and the loss of
+speed is acceptable, this kind of rewriting will allow you to process patterns
+that PCRE cannot otherwise handle.
+</P>
+<br><b>
+STACK USAGE AT RUN TIME
+</b><br>
+<P>
+When <b>pcre_exec()</b> or <b>pcre[16|32]_exec()</b> is used for matching, certain
+kinds of pattern can cause it to use large amounts of the process stack. In
+some environments the default process stack is quite small, and if it runs out
+the result is often SIGSEGV. This issue is probably the most frequently raised
+problem with PCRE. Rewriting your pattern can often help. The
+<a href="pcrestack.html"><b>pcrestack</b></a>
+documentation discusses this issue in detail.
+</P>
+<br><b>
+PROCESSING TIME
+</b><br>
+<P>
+Certain items in regular expression patterns are processed more efficiently
+than others. It is more efficient to use a character class like [aeiou] than a
+set of single-character alternatives such as (a|e|i|o|u). In general, the
+simplest construction that provides the required behaviour is usually the most
+efficient. Jeffrey Friedl's book contains a lot of useful general discussion
+about optimizing regular expressions for efficient performance. This document
+contains a few observations about PCRE.
+</P>
+<P>
+Using Unicode character properties (the \p, \P, and \X escapes) is slow,
+because PCRE has to use a multi-stage table lookup whenever it needs a
+character's property. If you can find an alternative pattern that does not use
+character properties, it will probably be faster.
+</P>
+<P>
+By default, the escape sequences \b, \d, \s, and \w, and the POSIX
+character classes such as [:alpha:] do not use Unicode properties, partly for
+backwards compatibility, and partly for performance reasons. However, you can
+set PCRE_UCP if you want Unicode character properties to be used. This can
+double the matching time for items such as \d, when matched with
+a traditional matching function; the performance loss is less with
+a DFA matching function, and in both cases there is not much difference for
+\b.
+</P>
+<P>
+When a pattern begins with .* not in parentheses, or in parentheses that are
+not the subject of a backreference, and the PCRE_DOTALL option is set, the
+pattern is implicitly anchored by PCRE, since it can match only at the start of
+a subject string. However, if PCRE_DOTALL is not set, PCRE cannot make this
+optimization, because the . metacharacter does not then match a newline, and if
+the subject string contains newlines, the pattern may match from the character
+immediately following one of them instead of from the very start. For example,
+the pattern
+<pre>
+  .*second
+</pre>
+matches the subject "first\nand second" (where \n stands for a newline
+character), with the match starting at the seventh character. In order to do
+this, PCRE has to retry the match starting after every newline in the subject.
+</P>
+<P>
+If you are using such a pattern with subject strings that do not contain
+newlines, the best performance is obtained by setting PCRE_DOTALL, or starting
+the pattern with ^.* or ^.*? to indicate explicit anchoring. That saves PCRE
+from having to scan along the subject looking for a newline to restart at.
+</P>
+<P>
+Beware of patterns that contain nested indefinite repeats. These can take a
+long time to run when applied to a string that does not match. Consider the
+pattern fragment
+<pre>
+  ^(a+)*
+</pre>
+This can match "aaaa" in 16 different ways, and this number increases very
+rapidly as the string gets longer. (The * repeat can match 0, 1, 2, 3, or 4
+times, and for each of those cases other than 0 or 4, the + repeats can match
+different numbers of times.) When the remainder of the pattern is such that the
+entire match is going to fail, PCRE has in principle to try every possible
+variation, and this can take an extremely long time, even for relatively short
+strings.
+</P>
+<P>
+An optimization catches some of the more simple cases such as
+<pre>
+  (a+)*b
+</pre>
+where a literal character follows. Before embarking on the standard matching
+procedure, PCRE checks that there is a "b" later in the subject string, and if
+there is not, it fails the match immediately. However, when there is no
+following literal this optimization cannot be used. You can see the difference
+by comparing the behaviour of
+<pre>
+  (a+)*\d
+</pre>
+with the pattern above. The former gives a failure almost instantly when
+applied to a whole line of "a" characters, whereas the latter takes an
+appreciable time with strings longer than about 20 characters.
+</P>
+<P>
+In many cases, the solution to this kind of performance issue is to use an
+atomic group or a possessive quantifier.
+</P>
+<br><b>
+AUTHOR
+</b><br>
+<P>
+Philip Hazel
+<br>
+University Computing Service
+<br>
+Cambridge CB2 3QH, England.
+<br>
+</P>
+<br><b>
+REVISION
+</b><br>
+<P>
+Last updated: 25 August 2012
+<br>
+Copyright &copy; 1997-2012 University of Cambridge.
+<br>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcreposix.html b/libs/Pcre16/docs/doc/html/pcreposix.html
new file mode 100644
index 0000000000..18924cf7f9
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcreposix.html
@@ -0,0 +1,290 @@
+<html>
+<head>
+<title>pcreposix specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcreposix man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<ul>
+<li><a name="TOC1" href="#SEC1">SYNOPSIS</a>
+<li><a name="TOC2" href="#SEC2">DESCRIPTION</a>
+<li><a name="TOC3" href="#SEC3">COMPILING A PATTERN</a>
+<li><a name="TOC4" href="#SEC4">MATCHING NEWLINE CHARACTERS</a>
+<li><a name="TOC5" href="#SEC5">MATCHING A PATTERN</a>
+<li><a name="TOC6" href="#SEC6">ERROR MESSAGES</a>
+<li><a name="TOC7" href="#SEC7">MEMORY USAGE</a>
+<li><a name="TOC8" href="#SEC8">AUTHOR</a>
+<li><a name="TOC9" href="#SEC9">REVISION</a>
+</ul>
+<br><a name="SEC1" href="#TOC1">SYNOPSIS</a><br>
+<P>
+<b>#include &#60;pcreposix.h&#62;</b>
+</P>
+<P>
+<b>int regcomp(regex_t *<i>preg</i>, const char *<i>pattern</i>,</b>
+<b>     int <i>cflags</i>);</b>
+<br>
+<br>
+<b>int regexec(regex_t *<i>preg</i>, const char *<i>string</i>,</b>
+<b>     size_t <i>nmatch</i>, regmatch_t <i>pmatch</i>[], int <i>eflags</i>);</b>
+<b>     size_t regerror(int <i>errcode</i>, const regex_t *<i>preg</i>,</b>
+<b>     char *<i>errbuf</i>, size_t <i>errbuf_size</i>);</b>
+<br>
+<br>
+<b>void regfree(regex_t *<i>preg</i>);</b>
+</P>
+<br><a name="SEC2" href="#TOC1">DESCRIPTION</a><br>
+<P>
+This set of functions provides a POSIX-style API for the PCRE regular
+expression 8-bit library. See the
+<a href="pcreapi.html"><b>pcreapi</b></a>
+documentation for a description of PCRE's native API, which contains much
+additional functionality. There is no POSIX-style wrapper for PCRE's 16-bit
+and 32-bit library.
+</P>
+<P>
+The functions described here are just wrapper functions that ultimately call
+the PCRE native API. Their prototypes are defined in the <b>pcreposix.h</b>
+header file, and on Unix systems the library itself is called
+<b>pcreposix.a</b>, so can be accessed by adding <b>-lpcreposix</b> to the
+command for linking an application that uses them. Because the POSIX functions
+call the native ones, it is also necessary to add <b>-lpcre</b>.
+</P>
+<P>
+I have implemented only those POSIX option bits that can be reasonably mapped
+to PCRE native options. In addition, the option REG_EXTENDED is defined with
+the value zero. This has no effect, but since programs that are written to the
+POSIX interface often use it, this makes it easier to slot in PCRE as a
+replacement library. Other POSIX options are not even defined.
+</P>
+<P>
+There are also some other options that are not defined by POSIX. These have
+been added at the request of users who want to make use of certain
+PCRE-specific features via the POSIX calling interface.
+</P>
+<P>
+When PCRE is called via these functions, it is only the API that is POSIX-like
+in style. The syntax and semantics of the regular expressions themselves are
+still those of Perl, subject to the setting of various PCRE options, as
+described below. "POSIX-like in style" means that the API approximates to the
+POSIX definition; it is not fully POSIX-compatible, and in multi-byte encoding
+domains it is probably even less compatible.
+</P>
+<P>
+The header for these functions is supplied as <b>pcreposix.h</b> to avoid any
+potential clash with other POSIX libraries. It can, of course, be renamed or
+aliased as <b>regex.h</b>, which is the "correct" name. It provides two
+structure types, <i>regex_t</i> for compiled internal forms, and
+<i>regmatch_t</i> for returning captured substrings. It also defines some
+constants whose names start with "REG_"; these are used for setting options and
+identifying error codes.
+</P>
+<br><a name="SEC3" href="#TOC1">COMPILING A PATTERN</a><br>
+<P>
+The function <b>regcomp()</b> is called to compile a pattern into an
+internal form. The pattern is a C string terminated by a binary zero, and
+is passed in the argument <i>pattern</i>. The <i>preg</i> argument is a pointer
+to a <b>regex_t</b> structure that is used as a base for storing information
+about the compiled regular expression.
+</P>
+<P>
+The argument <i>cflags</i> is either zero, or contains one or more of the bits
+defined by the following macros:
+<pre>
+  REG_DOTALL
+</pre>
+The PCRE_DOTALL option is set when the regular expression is passed for
+compilation to the native function. Note that REG_DOTALL is not part of the
+POSIX standard.
+<pre>
+  REG_ICASE
+</pre>
+The PCRE_CASELESS option is set when the regular expression is passed for
+compilation to the native function.
+<pre>
+  REG_NEWLINE
+</pre>
+The PCRE_MULTILINE option is set when the regular expression is passed for
+compilation to the native function. Note that this does <i>not</i> mimic the
+defined POSIX behaviour for REG_NEWLINE (see the following section).
+<pre>
+  REG_NOSUB
+</pre>
+The PCRE_NO_AUTO_CAPTURE option is set when the regular expression is passed
+for compilation to the native function. In addition, when a pattern that is
+compiled with this flag is passed to <b>regexec()</b> for matching, the
+<i>nmatch</i> and <i>pmatch</i> arguments are ignored, and no captured strings
+are returned.
+<pre>
+  REG_UCP
+</pre>
+The PCRE_UCP option is set when the regular expression is passed for
+compilation to the native function. This causes PCRE to use Unicode properties
+when matchine \d, \w, etc., instead of just recognizing ASCII values. Note
+that REG_UTF8 is not part of the POSIX standard.
+<pre>
+  REG_UNGREEDY
+</pre>
+The PCRE_UNGREEDY option is set when the regular expression is passed for
+compilation to the native function. Note that REG_UNGREEDY is not part of the
+POSIX standard.
+<pre>
+  REG_UTF8
+</pre>
+The PCRE_UTF8 option is set when the regular expression is passed for
+compilation to the native function. This causes the pattern itself and all data
+strings used for matching it to be treated as UTF-8 strings. Note that REG_UTF8
+is not part of the POSIX standard.
+</P>
+<P>
+In the absence of these flags, no options are passed to the native function.
+This means the the regex is compiled with PCRE default semantics. In
+particular, the way it handles newline characters in the subject string is the
+Perl way, not the POSIX way. Note that setting PCRE_MULTILINE has only
+<i>some</i> of the effects specified for REG_NEWLINE. It does not affect the way
+newlines are matched by . (they are not) or by a negative class such as [^a]
+(they are).
+</P>
+<P>
+The yield of <b>regcomp()</b> is zero on success, and non-zero otherwise. The
+<i>preg</i> structure is filled in on success, and one member of the structure
+is public: <i>re_nsub</i> contains the number of capturing subpatterns in
+the regular expression. Various error codes are defined in the header file.
+</P>
+<P>
+NOTE: If the yield of <b>regcomp()</b> is non-zero, you must not attempt to
+use the contents of the <i>preg</i> structure. If, for example, you pass it to
+<b>regexec()</b>, the result is undefined and your program is likely to crash.
+</P>
+<br><a name="SEC4" href="#TOC1">MATCHING NEWLINE CHARACTERS</a><br>
+<P>
+This area is not simple, because POSIX and Perl take different views of things.
+It is not possible to get PCRE to obey POSIX semantics, but then PCRE was never
+intended to be a POSIX engine. The following table lists the different
+possibilities for matching newline characters in PCRE:
+<pre>
+                          Default   Change with
+
+  . matches newline          no     PCRE_DOTALL
+  newline matches [^a]       yes    not changeable
+  $ matches \n at end        yes    PCRE_DOLLARENDONLY
+  $ matches \n in middle     no     PCRE_MULTILINE
+  ^ matches \n in middle     no     PCRE_MULTILINE
+</pre>
+This is the equivalent table for POSIX:
+<pre>
+                          Default   Change with
+
+  . matches newline          yes    REG_NEWLINE
+  newline matches [^a]       yes    REG_NEWLINE
+  $ matches \n at end        no     REG_NEWLINE
+  $ matches \n in middle     no     REG_NEWLINE
+  ^ matches \n in middle     no     REG_NEWLINE
+</pre>
+PCRE's behaviour is the same as Perl's, except that there is no equivalent for
+PCRE_DOLLAR_ENDONLY in Perl. In both PCRE and Perl, there is no way to stop
+newline from matching [^a].
+</P>
+<P>
+The default POSIX newline handling can be obtained by setting PCRE_DOTALL and
+PCRE_DOLLAR_ENDONLY, but there is no way to make PCRE behave exactly as for the
+REG_NEWLINE action.
+</P>
+<br><a name="SEC5" href="#TOC1">MATCHING A PATTERN</a><br>
+<P>
+The function <b>regexec()</b> is called to match a compiled pattern <i>preg</i>
+against a given <i>string</i>, which is by default terminated by a zero byte
+(but see REG_STARTEND below), subject to the options in <i>eflags</i>. These can
+be:
+<pre>
+  REG_NOTBOL
+</pre>
+The PCRE_NOTBOL option is set when calling the underlying PCRE matching
+function.
+<pre>
+  REG_NOTEMPTY
+</pre>
+The PCRE_NOTEMPTY option is set when calling the underlying PCRE matching
+function. Note that REG_NOTEMPTY is not part of the POSIX standard. However,
+setting this option can give more POSIX-like behaviour in some situations.
+<pre>
+  REG_NOTEOL
+</pre>
+The PCRE_NOTEOL option is set when calling the underlying PCRE matching
+function.
+<pre>
+  REG_STARTEND
+</pre>
+The string is considered to start at <i>string</i> + <i>pmatch[0].rm_so</i> and
+to have a terminating NUL located at <i>string</i> + <i>pmatch[0].rm_eo</i>
+(there need not actually be a NUL at that location), regardless of the value of
+<i>nmatch</i>. This is a BSD extension, compatible with but not specified by
+IEEE Standard 1003.2 (POSIX.2), and should be used with caution in software
+intended to be portable to other systems. Note that a non-zero <i>rm_so</i> does
+not imply REG_NOTBOL; REG_STARTEND affects only the location of the string, not
+how it is matched.
+</P>
+<P>
+If the pattern was compiled with the REG_NOSUB flag, no data about any matched
+strings is returned. The <i>nmatch</i> and <i>pmatch</i> arguments of
+<b>regexec()</b> are ignored.
+</P>
+<P>
+If the value of <i>nmatch</i> is zero, or if the value <i>pmatch</i> is NULL,
+no data about any matched strings is returned.
+</P>
+<P>
+Otherwise,the portion of the string that was matched, and also any captured
+substrings, are returned via the <i>pmatch</i> argument, which points to an
+array of <i>nmatch</i> structures of type <i>regmatch_t</i>, containing the
+members <i>rm_so</i> and <i>rm_eo</i>. These contain the offset to the first
+character of each substring and the offset to the first character after the end
+of each substring, respectively. The 0th element of the vector relates to the
+entire portion of <i>string</i> that was matched; subsequent elements relate to
+the capturing subpatterns of the regular expression. Unused entries in the
+array have both structure members set to -1.
+</P>
+<P>
+A successful match yields a zero return; various error codes are defined in the
+header file, of which REG_NOMATCH is the "expected" failure code.
+</P>
+<br><a name="SEC6" href="#TOC1">ERROR MESSAGES</a><br>
+<P>
+The <b>regerror()</b> function maps a non-zero errorcode from either
+<b>regcomp()</b> or <b>regexec()</b> to a printable message. If <i>preg</i> is not
+NULL, the error should have arisen from the use of that structure. A message
+terminated by a binary zero is placed in <i>errbuf</i>. The length of the
+message, including the zero, is limited to <i>errbuf_size</i>. The yield of the
+function is the size of buffer needed to hold the whole message.
+</P>
+<br><a name="SEC7" href="#TOC1">MEMORY USAGE</a><br>
+<P>
+Compiling a regular expression causes memory to be allocated and associated
+with the <i>preg</i> structure. The function <b>regfree()</b> frees all such
+memory, after which <i>preg</i> may no longer be used as a compiled expression.
+</P>
+<br><a name="SEC8" href="#TOC1">AUTHOR</a><br>
+<P>
+Philip Hazel
+<br>
+University Computing Service
+<br>
+Cambridge CB2 3QH, England.
+<br>
+</P>
+<br><a name="SEC9" href="#TOC1">REVISION</a><br>
+<P>
+Last updated: 09 January 2012
+<br>
+Copyright &copy; 1997-2012 University of Cambridge.
+<br>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcreprecompile.html b/libs/Pcre16/docs/doc/html/pcreprecompile.html
new file mode 100644
index 0000000000..decb1d6ce0
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcreprecompile.html
@@ -0,0 +1,163 @@
+<html>
+<head>
+<title>pcreprecompile specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcreprecompile man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<ul>
+<li><a name="TOC1" href="#SEC1">SAVING AND RE-USING PRECOMPILED PCRE PATTERNS</a>
+<li><a name="TOC2" href="#SEC2">SAVING A COMPILED PATTERN</a>
+<li><a name="TOC3" href="#SEC3">RE-USING A PRECOMPILED PATTERN</a>
+<li><a name="TOC4" href="#SEC4">COMPATIBILITY WITH DIFFERENT PCRE RELEASES</a>
+<li><a name="TOC5" href="#SEC5">AUTHOR</a>
+<li><a name="TOC6" href="#SEC6">REVISION</a>
+</ul>
+<br><a name="SEC1" href="#TOC1">SAVING AND RE-USING PRECOMPILED PCRE PATTERNS</a><br>
+<P>
+If you are running an application that uses a large number of regular
+expression patterns, it may be useful to store them in a precompiled form
+instead of having to compile them every time the application is run.
+If you are not using any private character tables (see the
+<a href="pcre_maketables.html"><b>pcre_maketables()</b></a>
+documentation), this is relatively straightforward. If you are using private
+tables, it is a little bit more complicated. However, if you are using the
+just-in-time optimization feature, it is not possible to save and reload the
+JIT data.
+</P>
+<P>
+If you save compiled patterns to a file, you can copy them to a different host
+and run them there. If the two hosts have different endianness (byte order),
+you should run the <b>pcre[16|32]_pattern_to_host_byte_order()</b> function on the
+new host before trying to match the pattern. The matching functions return
+PCRE_ERROR_BADENDIANNESS if they detect a pattern with the wrong endianness.
+</P>
+<P>
+Compiling regular expressions with one version of PCRE for use with a different
+version is not guaranteed to work and may cause crashes, and saving and
+restoring a compiled pattern loses any JIT optimization data.
+</P>
+<br><a name="SEC2" href="#TOC1">SAVING A COMPILED PATTERN</a><br>
+<P>
+The value returned by <b>pcre[16|32]_compile()</b> points to a single block of
+memory that holds the compiled pattern and associated data. You can find the
+length of this block in bytes by calling <b>pcre[16|32]_fullinfo()</b> with an
+argument of PCRE_INFO_SIZE. You can then save the data in any appropriate
+manner. Here is sample code for the 8-bit library that compiles a pattern and
+writes it to a file. It assumes that the variable <i>fd</i> refers to a file
+that is open for output:
+<pre>
+  int erroroffset, rc, size;
+  char *error;
+  pcre *re;
+
+  re = pcre_compile("my pattern", 0, &error, &erroroffset, NULL);
+  if (re == NULL) { ... handle errors ... }
+  rc = pcre_fullinfo(re, NULL, PCRE_INFO_SIZE, &size);
+  if (rc &#60; 0) { ... handle errors ... }
+  rc = fwrite(re, 1, size, fd);
+  if (rc != size) { ... handle errors ... }
+</pre>
+In this example, the bytes that comprise the compiled pattern are copied
+exactly. Note that this is binary data that may contain any of the 256 possible
+byte values. On systems that make a distinction between binary and non-binary
+data, be sure that the file is opened for binary output.
+</P>
+<P>
+If you want to write more than one pattern to a file, you will have to devise a
+way of separating them. For binary data, preceding each pattern with its length
+is probably the most straightforward approach. Another possibility is to write
+out the data in hexadecimal instead of binary, one pattern to a line.
+</P>
+<P>
+Saving compiled patterns in a file is only one possible way of storing them for
+later use. They could equally well be saved in a database, or in the memory of
+some daemon process that passes them via sockets to the processes that want
+them.
+</P>
+<P>
+If the pattern has been studied, it is also possible to save the normal study
+data in a similar way to the compiled pattern itself. However, if the
+PCRE_STUDY_JIT_COMPILE was used, the just-in-time data that is created cannot
+be saved because it is too dependent on the current environment. When studying
+generates additional information, <b>pcre[16|32]_study()</b> returns a pointer to a
+<b>pcre[16|32]_extra</b> data block. Its format is defined in the
+<a href="pcreapi.html#extradata">section on matching a pattern</a>
+in the
+<a href="pcreapi.html"><b>pcreapi</b></a>
+documentation. The <i>study_data</i> field points to the binary study data, and
+this is what you must save (not the <b>pcre[16|32]_extra</b> block itself). The
+length of the study data can be obtained by calling <b>pcre[16|32]_fullinfo()</b>
+with an argument of PCRE_INFO_STUDYSIZE. Remember to check that
+<b>pcre[16|32]_study()</b> did return a non-NULL value before trying to save the
+study data.
+</P>
+<br><a name="SEC3" href="#TOC1">RE-USING A PRECOMPILED PATTERN</a><br>
+<P>
+Re-using a precompiled pattern is straightforward. Having reloaded it into main
+memory, called <b>pcre[16|32]_pattern_to_host_byte_order()</b> if necessary, you
+pass its pointer to <b>pcre[16|32]_exec()</b> or <b>pcre[16|32]_dfa_exec()</b> in
+the usual way.
+</P>
+<P>
+However, if you passed a pointer to custom character tables when the pattern
+was compiled (the <i>tableptr</i> argument of <b>pcre[16|32]_compile()</b>), you
+must now pass a similar pointer to <b>pcre[16|32]_exec()</b> or
+<b>pcre[16|32]_dfa_exec()</b>, because the value saved with the compiled pattern
+will obviously be nonsense. A field in a <b>pcre[16|32]_extra()</b> block is used
+to pass this data, as described in the
+<a href="pcreapi.html#extradata">section on matching a pattern</a>
+in the
+<a href="pcreapi.html"><b>pcreapi</b></a>
+documentation.
+</P>
+<P>
+<b>Warning:</b> The tables that <b>pcre_exec()</b> and <b>pcre_dfa_exec()</b> use
+must be the same as those that were used when the pattern was compiled. If this
+is not the case, the behaviour is undefined.
+</P>
+<P>
+If you did not provide custom character tables when the pattern was compiled,
+the pointer in the compiled pattern is NULL, which causes the matching
+functions to use PCRE's internal tables. Thus, you do not need to take any
+special action at run time in this case.
+</P>
+<P>
+If you saved study data with the compiled pattern, you need to create your own
+<b>pcre[16|32]_extra</b> data block and set the <i>study_data</i> field to point
+to the reloaded study data. You must also set the PCRE_EXTRA_STUDY_DATA bit in
+the <i>flags</i> field to indicate that study data is present. Then pass the
+<b>pcre[16|32]_extra</b> block to the matching function in the usual way. If the
+pattern was studied for just-in-time optimization, that data cannot be saved,
+and so is lost by a save/restore cycle.
+</P>
+<br><a name="SEC4" href="#TOC1">COMPATIBILITY WITH DIFFERENT PCRE RELEASES</a><br>
+<P>
+In general, it is safest to recompile all saved patterns when you update to a
+new PCRE release, though not all updates actually require this.
+</P>
+<br><a name="SEC5" href="#TOC1">AUTHOR</a><br>
+<P>
+Philip Hazel
+<br>
+University Computing Service
+<br>
+Cambridge CB2 3QH, England.
+<br>
+</P>
+<br><a name="SEC6" href="#TOC1">REVISION</a><br>
+<P>
+Last updated: 12 November 2013
+<br>
+Copyright &copy; 1997-2013 University of Cambridge.
+<br>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcresample.html b/libs/Pcre16/docs/doc/html/pcresample.html
new file mode 100644
index 0000000000..aca9184e00
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcresample.html
@@ -0,0 +1,110 @@
+<html>
+<head>
+<title>pcresample specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcresample man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<br><b>
+PCRE SAMPLE PROGRAM
+</b><br>
+<P>
+A simple, complete demonstration program, to get you started with using PCRE,
+is supplied in the file <i>pcredemo.c</i> in the PCRE distribution. A listing of
+this program is given in the
+<a href="pcredemo.html"><b>pcredemo</b></a>
+documentation. If you do not have a copy of the PCRE distribution, you can save
+this listing to re-create <i>pcredemo.c</i>.
+</P>
+<P>
+The demonstration program, which uses the original PCRE 8-bit library, compiles
+the regular expression that is its first argument, and matches it against the
+subject string in its second argument. No PCRE options are set, and default
+character tables are used. If matching succeeds, the program outputs the
+portion of the subject that matched, together with the contents of any captured
+substrings.
+</P>
+<P>
+If the -g option is given on the command line, the program then goes on to
+check for further matches of the same regular expression in the same subject
+string. The logic is a little bit tricky because of the possibility of matching
+an empty string. Comments in the code explain what is going on.
+</P>
+<P>
+If PCRE is installed in the standard include and library directories for your
+operating system, you should be able to compile the demonstration program using
+this command:
+<pre>
+  gcc -o pcredemo pcredemo.c -lpcre
+</pre>
+If PCRE is installed elsewhere, you may need to add additional options to the
+command line. For example, on a Unix-like system that has PCRE installed in
+<i>/usr/local</i>, you can compile the demonstration program using a command
+like this:
+<pre>
+  gcc -o pcredemo -I/usr/local/include pcredemo.c -L/usr/local/lib -lpcre
+</pre>
+In a Windows environment, if you want to statically link the program against a
+non-dll <b>pcre.a</b> file, you must uncomment the line that defines PCRE_STATIC
+before including <b>pcre.h</b>, because otherwise the <b>pcre_malloc()</b> and
+<b>pcre_free()</b> exported functions will be declared
+<b>__declspec(dllimport)</b>, with unwanted results.
+</P>
+<P>
+Once you have compiled and linked the demonstration program, you can run simple
+tests like this:
+<pre>
+  ./pcredemo 'cat|dog' 'the cat sat on the mat'
+  ./pcredemo -g 'cat|dog' 'the dog sat on the cat'
+</pre>
+Note that there is a much more comprehensive test program, called
+<a href="pcretest.html"><b>pcretest</b>,</a>
+which supports many more facilities for testing regular expressions and both
+PCRE libraries. The
+<a href="pcredemo.html"><b>pcredemo</b></a>
+program is provided as a simple coding example.
+</P>
+<P>
+If you try to run
+<a href="pcredemo.html"><b>pcredemo</b></a>
+when PCRE is not installed in the standard library directory, you may get an
+error like this on some operating systems (e.g. Solaris):
+<pre>
+  ld.so.1: a.out: fatal: libpcre.so.0: open failed: No such file or directory
+</pre>
+This is caused by the way shared library support works on those systems. You
+need to add
+<pre>
+  -R/usr/local/lib
+</pre>
+(for example) to the compile command to get round this problem.
+</P>
+<br><b>
+AUTHOR
+</b><br>
+<P>
+Philip Hazel
+<br>
+University Computing Service
+<br>
+Cambridge CB2 3QH, England.
+<br>
+</P>
+<br><b>
+REVISION
+</b><br>
+<P>
+Last updated: 10 January 2012
+<br>
+Copyright &copy; 1997-2012 University of Cambridge.
+<br>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcrestack.html b/libs/Pcre16/docs/doc/html/pcrestack.html
new file mode 100644
index 0000000000..af6406d070
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcrestack.html
@@ -0,0 +1,225 @@
+<html>
+<head>
+<title>pcrestack specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcrestack man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<br><b>
+PCRE DISCUSSION OF STACK USAGE
+</b><br>
+<P>
+When you call <b>pcre[16|32]_exec()</b>, it makes use of an internal function
+called <b>match()</b>. This calls itself recursively at branch points in the
+pattern, in order to remember the state of the match so that it can back up and
+try a different alternative if the first one fails. As matching proceeds deeper
+and deeper into the tree of possibilities, the recursion depth increases. The
+<b>match()</b> function is also called in other circumstances, for example,
+whenever a parenthesized sub-pattern is entered, and in certain cases of
+repetition.
+</P>
+<P>
+Not all calls of <b>match()</b> increase the recursion depth; for an item such
+as a* it may be called several times at the same level, after matching
+different numbers of a's. Furthermore, in a number of cases where the result of
+the recursive call would immediately be passed back as the result of the
+current call (a "tail recursion"), the function is just restarted instead.
+</P>
+<P>
+The above comments apply when <b>pcre[16|32]_exec()</b> is run in its normal
+interpretive manner. If the pattern was studied with the
+PCRE_STUDY_JIT_COMPILE option, and just-in-time compiling was successful, and
+the options passed to <b>pcre[16|32]_exec()</b> were not incompatible, the matching
+process uses the JIT-compiled code instead of the <b>match()</b> function. In
+this case, the memory requirements are handled entirely differently. See the
+<a href="pcrejit.html"><b>pcrejit</b></a>
+documentation for details.
+</P>
+<P>
+The <b>pcre[16|32]_dfa_exec()</b> function operates in an entirely different way,
+and uses recursion only when there is a regular expression recursion or
+subroutine call in the pattern. This includes the processing of assertion and
+"once-only" subpatterns, which are handled like subroutine calls. Normally,
+these are never very deep, and the limit on the complexity of
+<b>pcre[16|32]_dfa_exec()</b> is controlled by the amount of workspace it is given.
+However, it is possible to write patterns with runaway infinite recursions;
+such patterns will cause <b>pcre[16|32]_dfa_exec()</b> to run out of stack. At
+present, there is no protection against this.
+</P>
+<P>
+The comments that follow do NOT apply to <b>pcre[16|32]_dfa_exec()</b>; they are
+relevant only for <b>pcre[16|32]_exec()</b> without the JIT optimization.
+</P>
+<br><b>
+Reducing <b>pcre[16|32]_exec()</b>'s stack usage
+</b><br>
+<P>
+Each time that <b>match()</b> is actually called recursively, it uses memory
+from the process stack. For certain kinds of pattern and data, very large
+amounts of stack may be needed, despite the recognition of "tail recursion".
+You can often reduce the amount of recursion, and therefore the amount of stack
+used, by modifying the pattern that is being matched. Consider, for example,
+this pattern:
+<pre>
+  ([^&#60;]|&#60;(?!inet))+
+</pre>
+It matches from wherever it starts until it encounters "&#60;inet" or the end of
+the data, and is the kind of pattern that might be used when processing an XML
+file. Each iteration of the outer parentheses matches either one character that
+is not "&#60;" or a "&#60;" that is not followed by "inet". However, each time a
+parenthesis is processed, a recursion occurs, so this formulation uses a stack
+frame for each matched character. For a long string, a lot of stack is
+required. Consider now this rewritten pattern, which matches exactly the same
+strings:
+<pre>
+  ([^&#60;]++|&#60;(?!inet))+
+</pre>
+This uses very much less stack, because runs of characters that do not contain
+"&#60;" are "swallowed" in one item inside the parentheses. Recursion happens only
+when a "&#60;" character that is not followed by "inet" is encountered (and we
+assume this is relatively rare). A possessive quantifier is used to stop any
+backtracking into the runs of non-"&#60;" characters, but that is not related to
+stack usage.
+</P>
+<P>
+This example shows that one way of avoiding stack problems when matching long
+subject strings is to write repeated parenthesized subpatterns to match more
+than one character whenever possible.
+</P>
+<br><b>
+Compiling PCRE to use heap instead of stack for <b>pcre[16|32]_exec()</b>
+</b><br>
+<P>
+In environments where stack memory is constrained, you might want to compile
+PCRE to use heap memory instead of stack for remembering back-up points when
+<b>pcre[16|32]_exec()</b> is running. This makes it run a lot more slowly, however.
+Details of how to do this are given in the
+<a href="pcrebuild.html"><b>pcrebuild</b></a>
+documentation. When built in this way, instead of using the stack, PCRE obtains
+and frees memory by calling the functions that are pointed to by the
+<b>pcre[16|32]_stack_malloc</b> and <b>pcre[16|32]_stack_free</b> variables. By
+default, these point to <b>malloc()</b> and <b>free()</b>, but you can replace
+the pointers to cause PCRE to use your own functions. Since the block sizes are
+always the same, and are always freed in reverse order, it may be possible to
+implement customized memory handlers that are more efficient than the standard
+functions.
+</P>
+<br><b>
+Limiting <b>pcre[16|32]_exec()</b>'s stack usage
+</b><br>
+<P>
+You can set limits on the number of times that <b>match()</b> is called, both in
+total and recursively. If a limit is exceeded, <b>pcre[16|32]_exec()</b> returns an
+error code. Setting suitable limits should prevent it from running out of
+stack. The default values of the limits are very large, and unlikely ever to
+operate. They can be changed when PCRE is built, and they can also be set when
+<b>pcre[16|32]_exec()</b> is called. For details of these interfaces, see the
+<a href="pcrebuild.html"><b>pcrebuild</b></a>
+documentation and the
+<a href="pcreapi.html#extradata">section on extra data for <b>pcre[16|32]_exec()</b></a>
+in the
+<a href="pcreapi.html"><b>pcreapi</b></a>
+documentation.
+</P>
+<P>
+As a very rough rule of thumb, you should reckon on about 500 bytes per
+recursion. Thus, if you want to limit your stack usage to 8Mb, you should set
+the limit at 16000 recursions. A 64Mb stack, on the other hand, can support
+around 128000 recursions.
+</P>
+<P>
+In Unix-like environments, the <b>pcretest</b> test program has a command line
+option (<b>-S</b>) that can be used to increase the size of its stack. As long
+as the stack is large enough, another option (<b>-M</b>) can be used to find the
+smallest limits that allow a particular pattern to match a given subject
+string. This is done by calling <b>pcre[16|32]_exec()</b> repeatedly with different
+limits.
+</P>
+<br><b>
+Obtaining an estimate of stack usage
+</b><br>
+<P>
+The actual amount of stack used per recursion can vary quite a lot, depending
+on the compiler that was used to build PCRE and the optimization or debugging
+options that were set for it. The rule of thumb value of 500 bytes mentioned
+above may be larger or smaller than what is actually needed. A better
+approximation can be obtained by running this command:
+<pre>
+  pcretest -m -C
+</pre>
+The <b>-C</b> option causes <b>pcretest</b> to output information about the
+options with which PCRE was compiled. When <b>-m</b> is also given (before
+<b>-C</b>), information about stack use is given in a line like this:
+<pre>
+  Match recursion uses stack: approximate frame size = 640 bytes
+</pre>
+The value is approximate because some recursions need a bit more (up to perhaps
+16 more bytes).
+</P>
+<P>
+If the above command is given when PCRE is compiled to use the heap instead of
+the stack for recursion, the value that is output is the size of each block
+that is obtained from the heap.
+</P>
+<br><b>
+Changing stack size in Unix-like systems
+</b><br>
+<P>
+In Unix-like environments, there is not often a problem with the stack unless
+very long strings are involved, though the default limit on stack size varies
+from system to system. Values from 8Mb to 64Mb are common. You can find your
+default limit by running the command:
+<pre>
+  ulimit -s
+</pre>
+Unfortunately, the effect of running out of stack is often SIGSEGV, though
+sometimes a more explicit error message is given. You can normally increase the
+limit on stack size by code such as this:
+<pre>
+  struct rlimit rlim;
+  getrlimit(RLIMIT_STACK, &rlim);
+  rlim.rlim_cur = 100*1024*1024;
+  setrlimit(RLIMIT_STACK, &rlim);
+</pre>
+This reads the current limits (soft and hard) using <b>getrlimit()</b>, then
+attempts to increase the soft limit to 100Mb using <b>setrlimit()</b>. You must
+do this before calling <b>pcre[16|32]_exec()</b>.
+</P>
+<br><b>
+Changing stack size in Mac OS X
+</b><br>
+<P>
+Using <b>setrlimit()</b>, as described above, should also work on Mac OS X. It
+is also possible to set a stack size when linking a program. There is a
+discussion about stack sizes in Mac OS X at this web site:
+<a href="http://developer.apple.com/qa/qa2005/qa1419.html">http://developer.apple.com/qa/qa2005/qa1419.html.</a>
+</P>
+<br><b>
+AUTHOR
+</b><br>
+<P>
+Philip Hazel
+<br>
+University Computing Service
+<br>
+Cambridge CB2 3QH, England.
+<br>
+</P>
+<br><b>
+REVISION
+</b><br>
+<P>
+Last updated: 24 June 2012
+<br>
+Copyright &copy; 1997-2012 University of Cambridge.
+<br>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcresyntax.html b/libs/Pcre16/docs/doc/html/pcresyntax.html
new file mode 100644
index 0000000000..89f35737b4
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcresyntax.html
@@ -0,0 +1,538 @@
+<html>
+<head>
+<title>pcresyntax specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcresyntax man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<ul>
+<li><a name="TOC1" href="#SEC1">PCRE REGULAR EXPRESSION SYNTAX SUMMARY</a>
+<li><a name="TOC2" href="#SEC2">QUOTING</a>
+<li><a name="TOC3" href="#SEC3">CHARACTERS</a>
+<li><a name="TOC4" href="#SEC4">CHARACTER TYPES</a>
+<li><a name="TOC5" href="#SEC5">GENERAL CATEGORY PROPERTIES FOR \p and \P</a>
+<li><a name="TOC6" href="#SEC6">PCRE SPECIAL CATEGORY PROPERTIES FOR \p and \P</a>
+<li><a name="TOC7" href="#SEC7">SCRIPT NAMES FOR \p AND \P</a>
+<li><a name="TOC8" href="#SEC8">CHARACTER CLASSES</a>
+<li><a name="TOC9" href="#SEC9">QUANTIFIERS</a>
+<li><a name="TOC10" href="#SEC10">ANCHORS AND SIMPLE ASSERTIONS</a>
+<li><a name="TOC11" href="#SEC11">MATCH POINT RESET</a>
+<li><a name="TOC12" href="#SEC12">ALTERNATION</a>
+<li><a name="TOC13" href="#SEC13">CAPTURING</a>
+<li><a name="TOC14" href="#SEC14">ATOMIC GROUPS</a>
+<li><a name="TOC15" href="#SEC15">COMMENT</a>
+<li><a name="TOC16" href="#SEC16">OPTION SETTING</a>
+<li><a name="TOC17" href="#SEC17">NEWLINE CONVENTION</a>
+<li><a name="TOC18" href="#SEC18">WHAT \R MATCHES</a>
+<li><a name="TOC19" href="#SEC19">LOOKAHEAD AND LOOKBEHIND ASSERTIONS</a>
+<li><a name="TOC20" href="#SEC20">BACKREFERENCES</a>
+<li><a name="TOC21" href="#SEC21">SUBROUTINE REFERENCES (POSSIBLY RECURSIVE)</a>
+<li><a name="TOC22" href="#SEC22">CONDITIONAL PATTERNS</a>
+<li><a name="TOC23" href="#SEC23">BACKTRACKING CONTROL</a>
+<li><a name="TOC24" href="#SEC24">CALLOUTS</a>
+<li><a name="TOC25" href="#SEC25">SEE ALSO</a>
+<li><a name="TOC26" href="#SEC26">AUTHOR</a>
+<li><a name="TOC27" href="#SEC27">REVISION</a>
+</ul>
+<br><a name="SEC1" href="#TOC1">PCRE REGULAR EXPRESSION SYNTAX SUMMARY</a><br>
+<P>
+The full syntax and semantics of the regular expressions that are supported by
+PCRE are described in the
+<a href="pcrepattern.html"><b>pcrepattern</b></a>
+documentation. This document contains a quick-reference summary of the syntax.
+</P>
+<br><a name="SEC2" href="#TOC1">QUOTING</a><br>
+<P>
+<pre>
+  \x         where x is non-alphanumeric is a literal x
+  \Q...\E    treat enclosed characters as literal
+</PRE>
+</P>
+<br><a name="SEC3" href="#TOC1">CHARACTERS</a><br>
+<P>
+<pre>
+  \a         alarm, that is, the BEL character (hex 07)
+  \cx        "control-x", where x is any ASCII character
+  \e         escape (hex 1B)
+  \f         form feed (hex 0C)
+  \n         newline (hex 0A)
+  \r         carriage return (hex 0D)
+  \t         tab (hex 09)
+  \0dd       character with octal code 0dd
+  \ddd       character with octal code ddd, or backreference
+  \o{ddd..}  character with octal code ddd..
+  \xhh       character with hex code hh
+  \x{hhh..}  character with hex code hhh..
+</pre>
+Note that \0dd is always an octal code, and that \8 and \9 are the literal
+characters "8" and "9".
+</P>
+<br><a name="SEC4" href="#TOC1">CHARACTER TYPES</a><br>
+<P>
+<pre>
+  .          any character except newline;
+               in dotall mode, any character whatsoever
+  \C         one data unit, even in UTF mode (best avoided)
+  \d         a decimal digit
+  \D         a character that is not a decimal digit
+  \h         a horizontal white space character
+  \H         a character that is not a horizontal white space character
+  \N         a character that is not a newline
+  \p{<i>xx</i>}     a character with the <i>xx</i> property
+  \P{<i>xx</i>}     a character without the <i>xx</i> property
+  \R         a newline sequence
+  \s         a white space character
+  \S         a character that is not a white space character
+  \v         a vertical white space character
+  \V         a character that is not a vertical white space character
+  \w         a "word" character
+  \W         a "non-word" character
+  \X         a Unicode extended grapheme cluster
+</pre>
+By default, \d, \s, and \w match only ASCII characters, even in UTF-8 mode
+or in the 16- bit and 32-bit libraries. However, if locale-specific matching is
+happening, \s and \w may also match characters with code points in the range
+128-255. If the PCRE_UCP option is set, the behaviour of these escape sequences
+is changed to use Unicode properties and they match many more characters.
+</P>
+<br><a name="SEC5" href="#TOC1">GENERAL CATEGORY PROPERTIES FOR \p and \P</a><br>
+<P>
+<pre>
+  C          Other
+  Cc         Control
+  Cf         Format
+  Cn         Unassigned
+  Co         Private use
+  Cs         Surrogate
+
+  L          Letter
+  Ll         Lower case letter
+  Lm         Modifier letter
+  Lo         Other letter
+  Lt         Title case letter
+  Lu         Upper case letter
+  L&         Ll, Lu, or Lt
+
+  M          Mark
+  Mc         Spacing mark
+  Me         Enclosing mark
+  Mn         Non-spacing mark
+
+  N          Number
+  Nd         Decimal number
+  Nl         Letter number
+  No         Other number
+
+  P          Punctuation
+  Pc         Connector punctuation
+  Pd         Dash punctuation
+  Pe         Close punctuation
+  Pf         Final punctuation
+  Pi         Initial punctuation
+  Po         Other punctuation
+  Ps         Open punctuation
+
+  S          Symbol
+  Sc         Currency symbol
+  Sk         Modifier symbol
+  Sm         Mathematical symbol
+  So         Other symbol
+
+  Z          Separator
+  Zl         Line separator
+  Zp         Paragraph separator
+  Zs         Space separator
+</PRE>
+</P>
+<br><a name="SEC6" href="#TOC1">PCRE SPECIAL CATEGORY PROPERTIES FOR \p and \P</a><br>
+<P>
+<pre>
+  Xan        Alphanumeric: union of properties L and N
+  Xps        POSIX space: property Z or tab, NL, VT, FF, CR
+  Xsp        Perl space: property Z or tab, NL, VT, FF, CR
+  Xuc        Univerally-named character: one that can be
+               represented by a Universal Character Name
+  Xwd        Perl word: property Xan or underscore
+</pre>
+Perl and POSIX space are now the same. Perl added VT to its space character set
+at release 5.18 and PCRE changed at release 8.34.
+</P>
+<br><a name="SEC7" href="#TOC1">SCRIPT NAMES FOR \p AND \P</a><br>
+<P>
+Arabic,
+Armenian,
+Avestan,
+Balinese,
+Bamum,
+Batak,
+Bengali,
+Bopomofo,
+Brahmi,
+Braille,
+Buginese,
+Buhid,
+Canadian_Aboriginal,
+Carian,
+Chakma,
+Cham,
+Cherokee,
+Common,
+Coptic,
+Cuneiform,
+Cypriot,
+Cyrillic,
+Deseret,
+Devanagari,
+Egyptian_Hieroglyphs,
+Ethiopic,
+Georgian,
+Glagolitic,
+Gothic,
+Greek,
+Gujarati,
+Gurmukhi,
+Han,
+Hangul,
+Hanunoo,
+Hebrew,
+Hiragana,
+Imperial_Aramaic,
+Inherited,
+Inscriptional_Pahlavi,
+Inscriptional_Parthian,
+Javanese,
+Kaithi,
+Kannada,
+Katakana,
+Kayah_Li,
+Kharoshthi,
+Khmer,
+Lao,
+Latin,
+Lepcha,
+Limbu,
+Linear_B,
+Lisu,
+Lycian,
+Lydian,
+Malayalam,
+Mandaic,
+Meetei_Mayek,
+Meroitic_Cursive,
+Meroitic_Hieroglyphs,
+Miao,
+Mongolian,
+Myanmar,
+New_Tai_Lue,
+Nko,
+Ogham,
+Old_Italic,
+Old_Persian,
+Old_South_Arabian,
+Old_Turkic,
+Ol_Chiki,
+Oriya,
+Osmanya,
+Phags_Pa,
+Phoenician,
+Rejang,
+Runic,
+Samaritan,
+Saurashtra,
+Sharada,
+Shavian,
+Sinhala,
+Sora_Sompeng,
+Sundanese,
+Syloti_Nagri,
+Syriac,
+Tagalog,
+Tagbanwa,
+Tai_Le,
+Tai_Tham,
+Tai_Viet,
+Takri,
+Tamil,
+Telugu,
+Thaana,
+Thai,
+Tibetan,
+Tifinagh,
+Ugaritic,
+Vai,
+Yi.
+</P>
+<br><a name="SEC8" href="#TOC1">CHARACTER CLASSES</a><br>
+<P>
+<pre>
+  [...]       positive character class
+  [^...]      negative character class
+  [x-y]       range (can be used for hex characters)
+  [[:xxx:]]   positive POSIX named set
+  [[:^xxx:]]  negative POSIX named set
+
+  alnum       alphanumeric
+  alpha       alphabetic
+  ascii       0-127
+  blank       space or tab
+  cntrl       control character
+  digit       decimal digit
+  graph       printing, excluding space
+  lower       lower case letter
+  print       printing, including space
+  punct       printing, excluding alphanumeric
+  space       white space
+  upper       upper case letter
+  word        same as \w
+  xdigit      hexadecimal digit
+</pre>
+In PCRE, POSIX character set names recognize only ASCII characters by default,
+but some of them use Unicode properties if PCRE_UCP is set. You can use
+\Q...\E inside a character class.
+</P>
+<br><a name="SEC9" href="#TOC1">QUANTIFIERS</a><br>
+<P>
+<pre>
+  ?           0 or 1, greedy
+  ?+          0 or 1, possessive
+  ??          0 or 1, lazy
+  *           0 or more, greedy
+  *+          0 or more, possessive
+  *?          0 or more, lazy
+  +           1 or more, greedy
+  ++          1 or more, possessive
+  +?          1 or more, lazy
+  {n}         exactly n
+  {n,m}       at least n, no more than m, greedy
+  {n,m}+      at least n, no more than m, possessive
+  {n,m}?      at least n, no more than m, lazy
+  {n,}        n or more, greedy
+  {n,}+       n or more, possessive
+  {n,}?       n or more, lazy
+</PRE>
+</P>
+<br><a name="SEC10" href="#TOC1">ANCHORS AND SIMPLE ASSERTIONS</a><br>
+<P>
+<pre>
+  \b          word boundary
+  \B          not a word boundary
+  ^           start of subject
+               also after internal newline in multiline mode
+  \A          start of subject
+  $           end of subject
+               also before newline at end of subject
+               also before internal newline in multiline mode
+  \Z          end of subject
+               also before newline at end of subject
+  \z          end of subject
+  \G          first matching position in subject
+</PRE>
+</P>
+<br><a name="SEC11" href="#TOC1">MATCH POINT RESET</a><br>
+<P>
+<pre>
+  \K          reset start of match
+</pre>
+\K is honoured in positive assertions, but ignored in negative ones.
+</P>
+<br><a name="SEC12" href="#TOC1">ALTERNATION</a><br>
+<P>
+<pre>
+  expr|expr|expr...
+</PRE>
+</P>
+<br><a name="SEC13" href="#TOC1">CAPTURING</a><br>
+<P>
+<pre>
+  (...)           capturing group
+  (?&#60;name&#62;...)    named capturing group (Perl)
+  (?'name'...)    named capturing group (Perl)
+  (?P&#60;name&#62;...)   named capturing group (Python)
+  (?:...)         non-capturing group
+  (?|...)         non-capturing group; reset group numbers for
+                   capturing groups in each alternative
+</PRE>
+</P>
+<br><a name="SEC14" href="#TOC1">ATOMIC GROUPS</a><br>
+<P>
+<pre>
+  (?&#62;...)         atomic, non-capturing group
+</PRE>
+</P>
+<br><a name="SEC15" href="#TOC1">COMMENT</a><br>
+<P>
+<pre>
+  (?#....)        comment (not nestable)
+</PRE>
+</P>
+<br><a name="SEC16" href="#TOC1">OPTION SETTING</a><br>
+<P>
+<pre>
+  (?i)            caseless
+  (?J)            allow duplicate names
+  (?m)            multiline
+  (?s)            single line (dotall)
+  (?U)            default ungreedy (lazy)
+  (?x)            extended (ignore white space)
+  (?-...)         unset option(s)
+</pre>
+The following are recognized only at the very start of a pattern or after one
+of the newline or \R options with similar syntax. More than one of them may
+appear.
+<pre>
+  (*LIMIT_MATCH=d) set the match limit to d (decimal number)
+  (*LIMIT_RECURSION=d) set the recursion limit to d (decimal number)
+  (*NO_AUTO_POSSESS) no auto-possessification (PCRE_NO_AUTO_POSSESS)
+  (*NO_START_OPT) no start-match optimization (PCRE_NO_START_OPTIMIZE)
+  (*UTF8)         set UTF-8 mode: 8-bit library (PCRE_UTF8)
+  (*UTF16)        set UTF-16 mode: 16-bit library (PCRE_UTF16)
+  (*UTF32)        set UTF-32 mode: 32-bit library (PCRE_UTF32)
+  (*UTF)          set appropriate UTF mode for the library in use
+  (*UCP)          set PCRE_UCP (use Unicode properties for \d etc)
+</pre>
+Note that LIMIT_MATCH and LIMIT_RECURSION can only reduce the value of the
+limits set by the caller of pcre_exec(), not increase them.
+</P>
+<br><a name="SEC17" href="#TOC1">NEWLINE CONVENTION</a><br>
+<P>
+These are recognized only at the very start of the pattern or after option
+settings with a similar syntax.
+<pre>
+  (*CR)           carriage return only
+  (*LF)           linefeed only
+  (*CRLF)         carriage return followed by linefeed
+  (*ANYCRLF)      all three of the above
+  (*ANY)          any Unicode newline sequence
+</PRE>
+</P>
+<br><a name="SEC18" href="#TOC1">WHAT \R MATCHES</a><br>
+<P>
+These are recognized only at the very start of the pattern or after option
+setting with a similar syntax.
+<pre>
+  (*BSR_ANYCRLF)  CR, LF, or CRLF
+  (*BSR_UNICODE)  any Unicode newline sequence
+</PRE>
+</P>
+<br><a name="SEC19" href="#TOC1">LOOKAHEAD AND LOOKBEHIND ASSERTIONS</a><br>
+<P>
+<pre>
+  (?=...)         positive look ahead
+  (?!...)         negative look ahead
+  (?&#60;=...)        positive look behind
+  (?&#60;!...)        negative look behind
+</pre>
+Each top-level branch of a look behind must be of a fixed length.
+</P>
+<br><a name="SEC20" href="#TOC1">BACKREFERENCES</a><br>
+<P>
+<pre>
+  \n              reference by number (can be ambiguous)
+  \gn             reference by number
+  \g{n}           reference by number
+  \g{-n}          relative reference by number
+  \k&#60;name&#62;        reference by name (Perl)
+  \k'name'        reference by name (Perl)
+  \g{name}        reference by name (Perl)
+  \k{name}        reference by name (.NET)
+  (?P=name)       reference by name (Python)
+</PRE>
+</P>
+<br><a name="SEC21" href="#TOC1">SUBROUTINE REFERENCES (POSSIBLY RECURSIVE)</a><br>
+<P>
+<pre>
+  (?R)            recurse whole pattern
+  (?n)            call subpattern by absolute number
+  (?+n)           call subpattern by relative number
+  (?-n)           call subpattern by relative number
+  (?&name)        call subpattern by name (Perl)
+  (?P&#62;name)       call subpattern by name (Python)
+  \g&#60;name&#62;        call subpattern by name (Oniguruma)
+  \g'name'        call subpattern by name (Oniguruma)
+  \g&#60;n&#62;           call subpattern by absolute number (Oniguruma)
+  \g'n'           call subpattern by absolute number (Oniguruma)
+  \g&#60;+n&#62;          call subpattern by relative number (PCRE extension)
+  \g'+n'          call subpattern by relative number (PCRE extension)
+  \g&#60;-n&#62;          call subpattern by relative number (PCRE extension)
+  \g'-n'          call subpattern by relative number (PCRE extension)
+</PRE>
+</P>
+<br><a name="SEC22" href="#TOC1">CONDITIONAL PATTERNS</a><br>
+<P>
+<pre>
+  (?(condition)yes-pattern)
+  (?(condition)yes-pattern|no-pattern)
+
+  (?(n)...        absolute reference condition
+  (?(+n)...       relative reference condition
+  (?(-n)...       relative reference condition
+  (?(&#60;name&#62;)...   named reference condition (Perl)
+  (?('name')...   named reference condition (Perl)
+  (?(name)...     named reference condition (PCRE)
+  (?(R)...        overall recursion condition
+  (?(Rn)...       specific group recursion condition
+  (?(R&name)...   specific recursion condition
+  (?(DEFINE)...   define subpattern for reference
+  (?(assert)...   assertion condition
+</PRE>
+</P>
+<br><a name="SEC23" href="#TOC1">BACKTRACKING CONTROL</a><br>
+<P>
+The following act immediately they are reached:
+<pre>
+  (*ACCEPT)       force successful match
+  (*FAIL)         force backtrack; synonym (*F)
+  (*MARK:NAME)    set name to be passed back; synonym (*:NAME)
+</pre>
+The following act only when a subsequent match failure causes a backtrack to
+reach them. They all force a match failure, but they differ in what happens
+afterwards. Those that advance the start-of-match point do so only if the
+pattern is not anchored.
+<pre>
+  (*COMMIT)       overall failure, no advance of starting point
+  (*PRUNE)        advance to next starting character
+  (*PRUNE:NAME)   equivalent to (*MARK:NAME)(*PRUNE)
+  (*SKIP)         advance to current matching position
+  (*SKIP:NAME)    advance to position corresponding to an earlier
+                  (*MARK:NAME); if not found, the (*SKIP) is ignored
+  (*THEN)         local failure, backtrack to next alternation
+  (*THEN:NAME)    equivalent to (*MARK:NAME)(*THEN)
+</PRE>
+</P>
+<br><a name="SEC24" href="#TOC1">CALLOUTS</a><br>
+<P>
+<pre>
+  (?C)      callout
+  (?Cn)     callout with data n
+</PRE>
+</P>
+<br><a name="SEC25" href="#TOC1">SEE ALSO</a><br>
+<P>
+<b>pcrepattern</b>(3), <b>pcreapi</b>(3), <b>pcrecallout</b>(3),
+<b>pcrematching</b>(3), <b>pcre</b>(3).
+</P>
+<br><a name="SEC26" href="#TOC1">AUTHOR</a><br>
+<P>
+Philip Hazel
+<br>
+University Computing Service
+<br>
+Cambridge CB2 3QH, England.
+<br>
+</P>
+<br><a name="SEC27" href="#TOC1">REVISION</a><br>
+<P>
+Last updated: 08 January 2014
+<br>
+Copyright &copy; 1997-2014 University of Cambridge.
+<br>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcretest.html b/libs/Pcre16/docs/doc/html/pcretest.html
new file mode 100644
index 0000000000..839fabf189
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcretest.html
@@ -0,0 +1,1158 @@
+<html>
+<head>
+<title>pcretest specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcretest man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<ul>
+<li><a name="TOC1" href="#SEC1">SYNOPSIS</a>
+<li><a name="TOC2" href="#SEC2">INPUT DATA FORMAT</a>
+<li><a name="TOC3" href="#SEC3">PCRE's 8-BIT, 16-BIT AND 32-BIT LIBRARIES</a>
+<li><a name="TOC4" href="#SEC4">COMMAND LINE OPTIONS</a>
+<li><a name="TOC5" href="#SEC5">DESCRIPTION</a>
+<li><a name="TOC6" href="#SEC6">PATTERN MODIFIERS</a>
+<li><a name="TOC7" href="#SEC7">DATA LINES</a>
+<li><a name="TOC8" href="#SEC8">THE ALTERNATIVE MATCHING FUNCTION</a>
+<li><a name="TOC9" href="#SEC9">DEFAULT OUTPUT FROM PCRETEST</a>
+<li><a name="TOC10" href="#SEC10">OUTPUT FROM THE ALTERNATIVE MATCHING FUNCTION</a>
+<li><a name="TOC11" href="#SEC11">RESTARTING AFTER A PARTIAL MATCH</a>
+<li><a name="TOC12" href="#SEC12">CALLOUTS</a>
+<li><a name="TOC13" href="#SEC13">NON-PRINTING CHARACTERS</a>
+<li><a name="TOC14" href="#SEC14">SAVING AND RELOADING COMPILED PATTERNS</a>
+<li><a name="TOC15" href="#SEC15">SEE ALSO</a>
+<li><a name="TOC16" href="#SEC16">AUTHOR</a>
+<li><a name="TOC17" href="#SEC17">REVISION</a>
+</ul>
+<br><a name="SEC1" href="#TOC1">SYNOPSIS</a><br>
+<P>
+<b>pcretest [options] [input file [output file]]</b>
+<br>
+<br>
+<b>pcretest</b> was written as a test program for the PCRE regular expression
+library itself, but it can also be used for experimenting with regular
+expressions. This document describes the features of the test program; for
+details of the regular expressions themselves, see the
+<a href="pcrepattern.html"><b>pcrepattern</b></a>
+documentation. For details of the PCRE library function calls and their
+options, see the
+<a href="pcreapi.html"><b>pcreapi</b></a>
+,
+<a href="pcre16.html"><b>pcre16</b></a>
+and
+<a href="pcre32.html"><b>pcre32</b></a>
+documentation.
+</P>
+<P>
+The input for <b>pcretest</b> is a sequence of regular expression patterns and
+strings to be matched, as described below. The output shows the result of each
+match. Options on the command line and the patterns control PCRE options and
+exactly what is output.
+</P>
+<P>
+As PCRE has evolved, it has acquired many different features, and as a result,
+<b>pcretest</b> now has rather a lot of obscure options for testing every
+possible feature. Some of these options are specifically designed for use in
+conjunction with the test script and data files that are distributed as part of
+PCRE, and are unlikely to be of use otherwise. They are all documented here,
+but without much justification.
+</P>
+<br><a name="SEC2" href="#TOC1">INPUT DATA FORMAT</a><br>
+<P>
+Input to <b>pcretest</b> is processed line by line, either by calling the C
+library's <b>fgets()</b> function, or via the <b>libreadline</b> library (see
+below). In Unix-like environments, <b>fgets()</b> treats any bytes other than
+newline as data characters. However, in some Windows environments character 26
+(hex 1A) causes an immediate end of file, and no further data is read. For
+maximum portability, therefore, it is safest to use only ASCII characters in
+<b>pcretest</b> input files.
+</P>
+<br><a name="SEC3" href="#TOC1">PCRE's 8-BIT, 16-BIT AND 32-BIT LIBRARIES</a><br>
+<P>
+From release 8.30, two separate PCRE libraries can be built. The original one
+supports 8-bit character strings, whereas the newer 16-bit library supports
+character strings encoded in 16-bit units. From release 8.32, a third library
+can be built, supporting character strings encoded in 32-bit units. The
+<b>pcretest</b> program can be used to test all three libraries. However, it is
+itself still an 8-bit program, reading 8-bit input and writing 8-bit output.
+When testing the 16-bit or 32-bit library, the patterns and data strings are
+converted to 16- or 32-bit format before being passed to the PCRE library
+functions. Results are converted to 8-bit for output.
+</P>
+<P>
+References to functions and structures of the form <b>pcre[16|32]_xx</b> below
+mean "<b>pcre_xx</b> when using the 8-bit library, <b>pcre16_xx</b> when using
+the 16-bit library, or <b>pcre32_xx</b> when using the 32-bit library".
+</P>
+<br><a name="SEC4" href="#TOC1">COMMAND LINE OPTIONS</a><br>
+<P>
+<b>-8</b>
+If both the 8-bit library has been built, this option causes the 8-bit library
+to be used (which is the default); if the 8-bit library has not been built,
+this option causes an error.
+</P>
+<P>
+<b>-16</b>
+If both the 8-bit or the 32-bit, and the 16-bit libraries have been built, this
+option causes the 16-bit library to be used. If only the 16-bit library has been
+built, this is the default (so has no effect). If only the 8-bit or the 32-bit
+library has been built, this option causes an error.
+</P>
+<P>
+<b>-32</b>
+If both the 8-bit or the 16-bit, and the 32-bit libraries have been built, this
+option causes the 32-bit library to be used. If only the 32-bit library has been
+built, this is the default (so has no effect). If only the 8-bit or the 16-bit
+library has been built, this option causes an error.
+</P>
+<P>
+<b>-b</b>
+Behave as if each pattern has the <b>/B</b> (show byte code) modifier; the
+internal form is output after compilation.
+</P>
+<P>
+<b>-C</b>
+Output the version number of the PCRE library, and all available information
+about the optional features that are included, and then exit with zero exit
+code. All other options are ignored.
+</P>
+<P>
+<b>-C</b> <i>option</i>
+Output information about a specific build-time option, then exit. This
+functionality is intended for use in scripts such as <b>RunTest</b>. The
+following options output the value and set the exit code as indicated:
+<pre>
+  ebcdic-nl  the code for LF (= NL) in an EBCDIC environment:
+               0x15 or 0x25
+               0 if used in an ASCII environment
+               exit code is always 0
+  linksize   the configured internal link size (2, 3, or 4)
+               exit code is set to the link size
+  newline    the default newline setting:
+               CR, LF, CRLF, ANYCRLF, or ANY
+               exit code is always 0
+  bsr        the default setting for what \R matches:
+               ANYCRLF or ANY
+               exit code is always 0
+</pre>
+The following options output 1 for true or 0 for false, and set the exit code
+to the same value:
+<pre>
+  ebcdic     compiled for an EBCDIC environment
+  jit        just-in-time support is available
+  pcre16     the 16-bit library was built
+  pcre32     the 32-bit library was built
+  pcre8      the 8-bit library was built
+  ucp        Unicode property support is available
+  utf        UTF-8 and/or UTF-16 and/or UTF-32 support
+               is available
+</pre>
+If an unknown option is given, an error message is output; the exit code is 0.
+</P>
+<P>
+<b>-d</b>
+Behave as if each pattern has the <b>/D</b> (debug) modifier; the internal
+form and information about the compiled pattern is output after compilation;
+<b>-d</b> is equivalent to <b>-b -i</b>.
+</P>
+<P>
+<b>-dfa</b>
+Behave as if each data line contains the \D escape sequence; this causes the
+alternative matching function, <b>pcre[16|32]_dfa_exec()</b>, to be used instead
+of the standard <b>pcre[16|32]_exec()</b> function (more detail is given below).
+</P>
+<P>
+<b>-help</b>
+Output a brief summary these options and then exit.
+</P>
+<P>
+<b>-i</b>
+Behave as if each pattern has the <b>/I</b> modifier; information about the
+compiled pattern is given after compilation.
+</P>
+<P>
+<b>-M</b>
+Behave as if each data line contains the \M escape sequence; this causes
+PCRE to discover the minimum MATCH_LIMIT and MATCH_LIMIT_RECURSION settings by
+calling <b>pcre[16|32]_exec()</b> repeatedly with different limits.
+</P>
+<P>
+<b>-m</b>
+Output the size of each compiled pattern after it has been compiled. This is
+equivalent to adding <b>/M</b> to each regular expression. The size is given in
+bytes for both libraries.
+</P>
+<P>
+<b>-O</b>
+Behave as if each pattern has the <b>/O</b> modifier, that is disable
+auto-possessification for all patterns.
+</P>
+<P>
+<b>-o</b> <i>osize</i>
+Set the number of elements in the output vector that is used when calling
+<b>pcre[16|32]_exec()</b> or <b>pcre[16|32]_dfa_exec()</b> to be <i>osize</i>. The
+default value is 45, which is enough for 14 capturing subexpressions for
+<b>pcre[16|32]_exec()</b> or 22 different matches for
+<b>pcre[16|32]_dfa_exec()</b>.
+The vector size can be changed for individual matching calls by including \O
+in the data line (see below).
+</P>
+<P>
+<b>-p</b>
+Behave as if each pattern has the <b>/P</b> modifier; the POSIX wrapper API is
+used to call PCRE. None of the other options has any effect when <b>-p</b> is
+set. This option can be used only with the 8-bit library.
+</P>
+<P>
+<b>-q</b>
+Do not output the version number of <b>pcretest</b> at the start of execution.
+</P>
+<P>
+<b>-S</b> <i>size</i>
+On Unix-like systems, set the size of the run-time stack to <i>size</i>
+megabytes.
+</P>
+<P>
+<b>-s</b> or <b>-s+</b>
+Behave as if each pattern has the <b>/S</b> modifier; in other words, force each
+pattern to be studied. If <b>-s+</b> is used, all the JIT compile options are
+passed to <b>pcre[16|32]_study()</b>, causing just-in-time optimization to be set
+up if it is available, for both full and partial matching. Specific JIT compile
+options can be selected by following <b>-s+</b> with a digit in the range 1 to
+7, which selects the JIT compile modes as follows:
+<pre>
+  1  normal match only
+  2  soft partial match only
+  3  normal match and soft partial match
+  4  hard partial match only
+  6  soft and hard partial match
+  7  all three modes (default)
+</pre>
+If <b>-s++</b> is used instead of <b>-s+</b> (with or without a following digit),
+the text "(JIT)" is added to the first output line after a match or no match
+when JIT-compiled code was actually used.
+<br>
+<br>
+Note that there are pattern options that can override <b>-s</b>, either
+specifying no studying at all, or suppressing JIT compilation.
+<br>
+<br>
+If the <b>/I</b> or <b>/D</b> option is present on a pattern (requesting output
+about the compiled pattern), information about the result of studying is not
+included when studying is caused only by <b>-s</b> and neither <b>-i</b> nor
+<b>-d</b> is present on the command line. This behaviour means that the output
+from tests that are run with and without <b>-s</b> should be identical, except
+when options that output information about the actual running of a match are
+set.
+<br>
+<br>
+The <b>-M</b>, <b>-t</b>, and <b>-tm</b> options, which give information about
+resources used, are likely to produce different output with and without
+<b>-s</b>. Output may also differ if the <b>/C</b> option is present on an
+individual pattern. This uses callouts to trace the the matching process, and
+this may be different between studied and non-studied patterns. If the pattern
+contains (*MARK) items there may also be differences, for the same reason. The
+<b>-s</b> command line option can be overridden for specific patterns that
+should never be studied (see the <b>/S</b> pattern modifier below).
+</P>
+<P>
+<b>-t</b>
+Run each compile, study, and match many times with a timer, and output the
+resulting times per compile, study, or match (in milliseconds). Do not set
+<b>-m</b> with <b>-t</b>, because you will then get the size output a zillion
+times, and the timing will be distorted. You can control the number of
+iterations that are used for timing by following <b>-t</b> with a number (as a
+separate item on the command line). For example, "-t 1000" iterates 1000 times.
+The default is to iterate 500000 times.
+</P>
+<P>
+<b>-tm</b>
+This is like <b>-t</b> except that it times only the matching phase, not the
+compile or study phases.
+</P>
+<P>
+<b>-T</b> <b>-TM</b>
+These behave like <b>-t</b> and <b>-tm</b>, but in addition, at the end of a run,
+the total times for all compiles, studies, and matches are output.
+</P>
+<br><a name="SEC5" href="#TOC1">DESCRIPTION</a><br>
+<P>
+If <b>pcretest</b> is given two filename arguments, it reads from the first and
+writes to the second. If it is given only one filename argument, it reads from
+that file and writes to stdout. Otherwise, it reads from stdin and writes to
+stdout, and prompts for each line of input, using "re&#62;" to prompt for regular
+expressions, and "data&#62;" to prompt for data lines.
+</P>
+<P>
+When <b>pcretest</b> is built, a configuration option can specify that it should
+be linked with the <b>libreadline</b> library. When this is done, if the input
+is from a terminal, it is read using the <b>readline()</b> function. This
+provides line-editing and history facilities. The output from the <b>-help</b>
+option states whether or not <b>readline()</b> will be used.
+</P>
+<P>
+The program handles any number of sets of input on a single input file. Each
+set starts with a regular expression, and continues with any number of data
+lines to be matched against that pattern.
+</P>
+<P>
+Each data line is matched separately and independently. If you want to do
+multi-line matches, you have to use the \n escape sequence (or \r or \r\n,
+etc., depending on the newline setting) in a single line of input to encode the
+newline sequences. There is no limit on the length of data lines; the input
+buffer is automatically extended if it is too small.
+</P>
+<P>
+An empty line signals the end of the data lines, at which point a new regular
+expression is read. The regular expressions are given enclosed in any
+non-alphanumeric delimiters other than backslash, for example:
+<pre>
+  /(a|bc)x+yz/
+</pre>
+White space before the initial delimiter is ignored. A regular expression may
+be continued over several input lines, in which case the newline characters are
+included within it. It is possible to include the delimiter within the pattern
+by escaping it, for example
+<pre>
+  /abc\/def/
+</pre>
+If you do so, the escape and the delimiter form part of the pattern, but since
+delimiters are always non-alphanumeric, this does not affect its interpretation.
+If the terminating delimiter is immediately followed by a backslash, for
+example,
+<pre>
+  /abc/\
+</pre>
+then a backslash is added to the end of the pattern. This is done to provide a
+way of testing the error condition that arises if a pattern finishes with a
+backslash, because
+<pre>
+  /abc\/
+</pre>
+is interpreted as the first line of a pattern that starts with "abc/", causing
+pcretest to read the next line as a continuation of the regular expression.
+</P>
+<br><a name="SEC6" href="#TOC1">PATTERN MODIFIERS</a><br>
+<P>
+A pattern may be followed by any number of modifiers, which are mostly single
+characters, though some of these can be qualified by further characters.
+Following Perl usage, these are referred to below as, for example, "the
+<b>/i</b> modifier", even though the delimiter of the pattern need not always be
+a slash, and no slash is used when writing modifiers. White space may appear
+between the final pattern delimiter and the first modifier, and between the
+modifiers themselves. For reference, here is a complete list of modifiers. They
+fall into several groups that are described in detail in the following
+sections.
+<pre>
+  <b>/8</b>              set UTF mode
+  <b>/9</b>              set PCRE_NEVER_UTF (locks out UTF mode)
+  <b>/?</b>              disable UTF validity check
+  <b>/+</b>              show remainder of subject after match
+  <b>/=</b>              show all captures (not just those that are set)
+
+  <b>/A</b>              set PCRE_ANCHORED
+  <b>/B</b>              show compiled code
+  <b>/C</b>              set PCRE_AUTO_CALLOUT
+  <b>/D</b>              same as <b>/B</b> plus <b>/I</b>
+  <b>/E</b>              set PCRE_DOLLAR_ENDONLY
+  <b>/F</b>              flip byte order in compiled pattern
+  <b>/f</b>              set PCRE_FIRSTLINE
+  <b>/G</b>              find all matches (shorten string)
+  <b>/g</b>              find all matches (use startoffset)
+  <b>/I</b>              show information about pattern
+  <b>/i</b>              set PCRE_CASELESS
+  <b>/J</b>              set PCRE_DUPNAMES
+  <b>/K</b>              show backtracking control names
+  <b>/L</b>              set locale
+  <b>/M</b>              show compiled memory size
+  <b>/m</b>              set PCRE_MULTILINE
+  <b>/N</b>              set PCRE_NO_AUTO_CAPTURE
+  <b>/O</b>              set PCRE_NO_AUTO_POSSESS
+  <b>/P</b>              use the POSIX wrapper
+  <b>/Q</b>              test external stack check function
+  <b>/S</b>              study the pattern after compilation
+  <b>/s</b>              set PCRE_DOTALL
+  <b>/T</b>              select character tables
+  <b>/U</b>              set PCRE_UNGREEDY
+  <b>/W</b>              set PCRE_UCP
+  <b>/X</b>              set PCRE_EXTRA
+  <b>/x</b>              set PCRE_EXTENDED
+  <b>/Y</b>              set PCRE_NO_START_OPTIMIZE
+  <b>/Z</b>              don't show lengths in <b>/B</b> output
+
+  <b>/&#60;any&#62;</b>          set PCRE_NEWLINE_ANY
+  <b>/&#60;anycrlf&#62;</b>      set PCRE_NEWLINE_ANYCRLF
+  <b>/&#60;cr&#62;</b>           set PCRE_NEWLINE_CR
+  <b>/&#60;crlf&#62;</b>         set PCRE_NEWLINE_CRLF
+  <b>/&#60;lf&#62;</b>           set PCRE_NEWLINE_LF
+  <b>/&#60;bsr_anycrlf&#62;</b>  set PCRE_BSR_ANYCRLF
+  <b>/&#60;bsr_unicode&#62;</b>  set PCRE_BSR_UNICODE
+  <b>/&#60;JS&#62;</b>           set PCRE_JAVASCRIPT_COMPAT
+
+</PRE>
+</P>
+<br><b>
+Perl-compatible modifiers
+</b><br>
+<P>
+The <b>/i</b>, <b>/m</b>, <b>/s</b>, and <b>/x</b> modifiers set the PCRE_CASELESS,
+PCRE_MULTILINE, PCRE_DOTALL, or PCRE_EXTENDED options, respectively, when
+<b>pcre[16|32]_compile()</b> is called. These four modifier letters have the same
+effect as they do in Perl. For example:
+<pre>
+  /caseless/i
+
+</PRE>
+</P>
+<br><b>
+Modifiers for other PCRE options
+</b><br>
+<P>
+The following table shows additional modifiers for setting PCRE compile-time
+options that do not correspond to anything in Perl:
+<pre>
+  <b>/8</b>              PCRE_UTF8           ) when using the 8-bit
+  <b>/?</b>              PCRE_NO_UTF8_CHECK  )   library
+
+  <b>/8</b>              PCRE_UTF16          ) when using the 16-bit
+  <b>/?</b>              PCRE_NO_UTF16_CHECK )   library
+
+  <b>/8</b>              PCRE_UTF32          ) when using the 32-bit
+  <b>/?</b>              PCRE_NO_UTF32_CHECK )   library
+
+  <b>/9</b>              PCRE_NEVER_UTF
+  <b>/A</b>              PCRE_ANCHORED
+  <b>/C</b>              PCRE_AUTO_CALLOUT
+  <b>/E</b>              PCRE_DOLLAR_ENDONLY
+  <b>/f</b>              PCRE_FIRSTLINE
+  <b>/J</b>              PCRE_DUPNAMES
+  <b>/N</b>              PCRE_NO_AUTO_CAPTURE
+  <b>/O</b>              PCRE_NO_AUTO_POSSESS
+  <b>/U</b>              PCRE_UNGREEDY
+  <b>/W</b>              PCRE_UCP
+  <b>/X</b>              PCRE_EXTRA
+  <b>/Y</b>              PCRE_NO_START_OPTIMIZE
+  <b>/&#60;any&#62;</b>          PCRE_NEWLINE_ANY
+  <b>/&#60;anycrlf&#62;</b>      PCRE_NEWLINE_ANYCRLF
+  <b>/&#60;cr&#62;</b>           PCRE_NEWLINE_CR
+  <b>/&#60;crlf&#62;</b>         PCRE_NEWLINE_CRLF
+  <b>/&#60;lf&#62;</b>           PCRE_NEWLINE_LF
+  <b>/&#60;bsr_anycrlf&#62;</b>  PCRE_BSR_ANYCRLF
+  <b>/&#60;bsr_unicode&#62;</b>  PCRE_BSR_UNICODE
+  <b>/&#60;JS&#62;</b>           PCRE_JAVASCRIPT_COMPAT
+</pre>
+The modifiers that are enclosed in angle brackets are literal strings as shown,
+including the angle brackets, but the letters within can be in either case.
+This example sets multiline matching with CRLF as the line ending sequence:
+<pre>
+  /^abc/m&#60;CRLF&#62;
+</pre>
+As well as turning on the PCRE_UTF8/16/32 option, the <b>/8</b> modifier causes
+all non-printing characters in output strings to be printed using the
+\x{hh...} notation. Otherwise, those less than 0x100 are output in hex without
+the curly brackets.
+</P>
+<P>
+Full details of the PCRE options are given in the
+<a href="pcreapi.html"><b>pcreapi</b></a>
+documentation.
+</P>
+<br><b>
+Finding all matches in a string
+</b><br>
+<P>
+Searching for all possible matches within each subject string can be requested
+by the <b>/g</b> or <b>/G</b> modifier. After finding a match, PCRE is called
+again to search the remainder of the subject string. The difference between
+<b>/g</b> and <b>/G</b> is that the former uses the <i>startoffset</i> argument to
+<b>pcre[16|32]_exec()</b> to start searching at a new point within the entire
+string (which is in effect what Perl does), whereas the latter passes over a
+shortened substring. This makes a difference to the matching process if the
+pattern begins with a lookbehind assertion (including \b or \B).
+</P>
+<P>
+If any call to <b>pcre[16|32]_exec()</b> in a <b>/g</b> or <b>/G</b> sequence matches
+an empty string, the next call is done with the PCRE_NOTEMPTY_ATSTART and
+PCRE_ANCHORED flags set in order to search for another, non-empty, match at the
+same point. If this second match fails, the start offset is advanced, and the
+normal match is retried. This imitates the way Perl handles such cases when
+using the <b>/g</b> modifier or the <b>split()</b> function. Normally, the start
+offset is advanced by one character, but if the newline convention recognizes
+CRLF as a newline, and the current character is CR followed by LF, an advance
+of two is used.
+</P>
+<br><b>
+Other modifiers
+</b><br>
+<P>
+There are yet more modifiers for controlling the way <b>pcretest</b>
+operates.
+</P>
+<P>
+The <b>/+</b> modifier requests that as well as outputting the substring that
+matched the entire pattern, <b>pcretest</b> should in addition output the
+remainder of the subject string. This is useful for tests where the subject
+contains multiple copies of the same substring. If the <b>+</b> modifier appears
+twice, the same action is taken for captured substrings. In each case the
+remainder is output on the following line with a plus character following the
+capture number. Note that this modifier must not immediately follow the /S
+modifier because /S+ and /S++ have other meanings.
+</P>
+<P>
+The <b>/=</b> modifier requests that the values of all potential captured
+parentheses be output after a match. By default, only those up to the highest
+one actually used in the match are output (corresponding to the return code
+from <b>pcre[16|32]_exec()</b>). Values in the offsets vector corresponding to
+higher numbers should be set to -1, and these are output as "&#60;unset&#62;". This
+modifier gives a way of checking that this is happening.
+</P>
+<P>
+The <b>/B</b> modifier is a debugging feature. It requests that <b>pcretest</b>
+output a representation of the compiled code after compilation. Normally this
+information contains length and offset values; however, if <b>/Z</b> is also
+present, this data is replaced by spaces. This is a special feature for use in
+the automatic test scripts; it ensures that the same output is generated for
+different internal link sizes.
+</P>
+<P>
+The <b>/D</b> modifier is a PCRE debugging feature, and is equivalent to
+<b>/BI</b>, that is, both the <b>/B</b> and the <b>/I</b> modifiers.
+</P>
+<P>
+The <b>/F</b> modifier causes <b>pcretest</b> to flip the byte order of the
+2-byte and 4-byte fields in the compiled pattern. This facility is for testing
+the feature in PCRE that allows it to execute patterns that were compiled on a
+host with a different endianness. This feature is not available when the POSIX
+interface to PCRE is being used, that is, when the <b>/P</b> pattern modifier is
+specified. See also the section about saving and reloading compiled patterns
+below.
+</P>
+<P>
+The <b>/I</b> modifier requests that <b>pcretest</b> output information about the
+compiled pattern (whether it is anchored, has a fixed first character, and
+so on). It does this by calling <b>pcre[16|32]_fullinfo()</b> after compiling a
+pattern. If the pattern is studied, the results of that are also output. In
+this output, the word "char" means a non-UTF character, that is, the value of a
+single data item (8-bit, 16-bit, or 32-bit, depending on the library that is
+being tested).
+</P>
+<P>
+The <b>/K</b> modifier requests <b>pcretest</b> to show names from backtracking
+control verbs that are returned from calls to <b>pcre[16|32]_exec()</b>. It causes
+<b>pcretest</b> to create a <b>pcre[16|32]_extra</b> block if one has not already
+been created by a call to <b>pcre[16|32]_study()</b>, and to set the
+PCRE_EXTRA_MARK flag and the <b>mark</b> field within it, every time that
+<b>pcre[16|32]_exec()</b> is called. If the variable that the <b>mark</b> field
+points to is non-NULL for a match, non-match, or partial match, <b>pcretest</b>
+prints the string to which it points. For a match, this is shown on a line by
+itself, tagged with "MK:". For a non-match it is added to the message.
+</P>
+<P>
+The <b>/L</b> modifier must be followed directly by the name of a locale, for
+example,
+<pre>
+  /pattern/Lfr_FR
+</pre>
+For this reason, it must be the last modifier. The given locale is set,
+<b>pcre[16|32]_maketables()</b> is called to build a set of character tables for
+the locale, and this is then passed to <b>pcre[16|32]_compile()</b> when compiling
+the regular expression. Without an <b>/L</b> (or <b>/T</b>) modifier, NULL is
+passed as the tables pointer; that is, <b>/L</b> applies only to the expression
+on which it appears.
+</P>
+<P>
+The <b>/M</b> modifier causes the size in bytes of the memory block used to hold
+the compiled pattern to be output. This does not include the size of the
+<b>pcre[16|32]</b> block; it is just the actual compiled data. If the pattern is
+successfully studied with the PCRE_STUDY_JIT_COMPILE option, the size of the
+JIT compiled code is also output.
+</P>
+<P>
+The <b>/Q</b> modifier is used to test the use of <b>pcre_stack_guard</b>. It
+must be followed by '0' or '1', specifying the return code to be given from an
+external function that is passed to PCRE and used for stack checking during
+compilation (see the
+<a href="pcreapi.html"><b>pcreapi</b></a>
+documentation for details).
+</P>
+<P>
+The <b>/S</b> modifier causes <b>pcre[16|32]_study()</b> to be called after the
+expression has been compiled, and the results used when the expression is
+matched. There are a number of qualifying characters that may follow <b>/S</b>.
+They may appear in any order.
+</P>
+<P>
+If <b>/S</b> is followed by an exclamation mark, <b>pcre[16|32]_study()</b> is
+called with the PCRE_STUDY_EXTRA_NEEDED option, causing it always to return a
+<b>pcre_extra</b> block, even when studying discovers no useful information.
+</P>
+<P>
+If <b>/S</b> is followed by a second S character, it suppresses studying, even
+if it was requested externally by the <b>-s</b> command line option. This makes
+it possible to specify that certain patterns are always studied, and others are
+never studied, independently of <b>-s</b>. This feature is used in the test
+files in a few cases where the output is different when the pattern is studied.
+</P>
+<P>
+If the <b>/S</b> modifier is followed by a + character, the call to
+<b>pcre[16|32]_study()</b> is made with all the JIT study options, requesting
+just-in-time optimization support if it is available, for both normal and
+partial matching. If you want to restrict the JIT compiling modes, you can
+follow <b>/S+</b> with a digit in the range 1 to 7:
+<pre>
+  1  normal match only
+  2  soft partial match only
+  3  normal match and soft partial match
+  4  hard partial match only
+  6  soft and hard partial match
+  7  all three modes (default)
+</pre>
+If <b>/S++</b> is used instead of <b>/S+</b> (with or without a following digit),
+the text "(JIT)" is added to the first output line after a match or no match
+when JIT-compiled code was actually used.
+</P>
+<P>
+Note that there is also an independent <b>/+</b> modifier; it must not be given
+immediately after <b>/S</b> or <b>/S+</b> because this will be misinterpreted.
+</P>
+<P>
+If JIT studying is successful, the compiled JIT code will automatically be used
+when <b>pcre[16|32]_exec()</b> is run, except when incompatible run-time options
+are specified. For more details, see the
+<a href="pcrejit.html"><b>pcrejit</b></a>
+documentation. See also the <b>\J</b> escape sequence below for a way of
+setting the size of the JIT stack.
+</P>
+<P>
+Finally, if <b>/S</b> is followed by a minus character, JIT compilation is
+suppressed, even if it was requested externally by the <b>-s</b> command line
+option. This makes it possible to specify that JIT is never to be used for
+certain patterns.
+</P>
+<P>
+The <b>/T</b> modifier must be followed by a single digit. It causes a specific
+set of built-in character tables to be passed to <b>pcre[16|32]_compile()</b>. It
+is used in the standard PCRE tests to check behaviour with different character
+tables. The digit specifies the tables as follows:
+<pre>
+  0   the default ASCII tables, as distributed in
+        pcre_chartables.c.dist
+  1   a set of tables defining ISO 8859 characters
+</pre>
+In table 1, some characters whose codes are greater than 128 are identified as
+letters, digits, spaces, etc.
+</P>
+<br><b>
+Using the POSIX wrapper API
+</b><br>
+<P>
+The <b>/P</b> modifier causes <b>pcretest</b> to call PCRE via the POSIX wrapper
+API rather than its native API. This supports only the 8-bit library. When
+<b>/P</b> is set, the following modifiers set options for the <b>regcomp()</b>
+function:
+<pre>
+  /i    REG_ICASE
+  /m    REG_NEWLINE
+  /N    REG_NOSUB
+  /s    REG_DOTALL     )
+  /U    REG_UNGREEDY   ) These options are not part of
+  /W    REG_UCP        )   the POSIX standard
+  /8    REG_UTF8       )
+</pre>
+The <b>/+</b> modifier works as described above. All other modifiers are
+ignored.
+</P>
+<br><b>
+Locking out certain modifiers
+</b><br>
+<P>
+PCRE can be compiled with or without support for certain features such as
+UTF-8/16/32 or Unicode properties. Accordingly, the standard tests are split up
+into a number of different files that are selected for running depending on
+which features are available. When updating the tests, it is all too easy to
+put a new test into the wrong file by mistake; for example, to put a test that
+requires UTF support into a file that is used when it is not available. To help
+detect such mistakes as early as possible, there is a facility for locking out
+specific modifiers. If an input line for <b>pcretest</b> starts with the string
+"&#60; forbid " the following sequence of characters is taken as a list of
+forbidden modifiers. For example, in the test files that must not use UTF or
+Unicode property support, this line appears:
+<pre>
+  &#60; forbid 8W
+</pre>
+This locks out the /8 and /W modifiers. An immediate error is given if they are
+subsequently encountered. If the character string contains &#60; but not &#62;, all the
+multi-character modifiers that begin with &#60; are locked out. Otherwise, such
+modifiers must be explicitly listed, for example:
+<pre>
+  &#60; forbid &#60;JS&#62;&#60;cr&#62;
+</pre>
+There must be a single space between &#60; and "forbid" for this feature to be
+recognised. If there is not, the line is interpreted either as a request to
+re-load a pre-compiled pattern (see "SAVING AND RELOADING COMPILED PATTERNS"
+below) or, if there is a another &#60; character, as a pattern that uses &#60; as its
+delimiter.
+</P>
+<br><a name="SEC7" href="#TOC1">DATA LINES</a><br>
+<P>
+Before each data line is passed to <b>pcre[16|32]_exec()</b>, leading and trailing
+white space is removed, and it is then scanned for \ escapes. Some of these
+are pretty esoteric features, intended for checking out some of the more
+complicated features of PCRE. If you are just testing "ordinary" regular
+expressions, you probably don't need any of these. The following escapes are
+recognized:
+<pre>
+  \a         alarm (BEL, \x07)
+  \b         backspace (\x08)
+  \e         escape (\x27)
+  \f         form feed (\x0c)
+  \n         newline (\x0a)
+  \qdd       set the PCRE_MATCH_LIMIT limit to dd (any number of digits)
+  \r         carriage return (\x0d)
+  \t         tab (\x09)
+  \v         vertical tab (\x0b)
+  \nnn       octal character (up to 3 octal digits); always
+               a byte unless &#62; 255 in UTF-8 or 16-bit or 32-bit mode
+  \o{dd...}  octal character (any number of octal digits}
+  \xhh       hexadecimal byte (up to 2 hex digits)
+  \x{hh...}  hexadecimal character (any number of hex digits)
+  \A         pass the PCRE_ANCHORED option to <b>pcre[16|32]_exec()</b> or <b>pcre[16|32]_dfa_exec()</b>
+  \B         pass the PCRE_NOTBOL option to <b>pcre[16|32]_exec()</b> or <b>pcre[16|32]_dfa_exec()</b>
+  \Cdd       call pcre[16|32]_copy_substring() for substring dd after a successful match (number less than 32)
+  \Cname     call pcre[16|32]_copy_named_substring() for substring "name" after a successful match (name termin-
+               ated by next non alphanumeric character)
+  \C+        show the current captured substrings at callout time
+  \C-        do not supply a callout function
+  \C!n       return 1 instead of 0 when callout number n is reached
+  \C!n!m     return 1 instead of 0 when callout number n is reached for the nth time
+  \C*n       pass the number n (may be negative) as callout data; this is used as the callout return value
+  \D         use the <b>pcre[16|32]_dfa_exec()</b> match function
+  \F         only shortest match for <b>pcre[16|32]_dfa_exec()</b>
+  \Gdd       call pcre[16|32]_get_substring() for substring dd after a successful match (number less than 32)
+  \Gname     call pcre[16|32]_get_named_substring() for substring "name" after a successful match (name termin-
+               ated by next non-alphanumeric character)
+  \Jdd       set up a JIT stack of dd kilobytes maximum (any number of digits)
+  \L         call pcre[16|32]_get_substringlist() after a successful match
+  \M         discover the minimum MATCH_LIMIT and MATCH_LIMIT_RECURSION settings
+  \N         pass the PCRE_NOTEMPTY option to <b>pcre[16|32]_exec()</b> or <b>pcre[16|32]_dfa_exec()</b>; if used twice, pass the
+               PCRE_NOTEMPTY_ATSTART option
+  \Odd       set the size of the output vector passed to <b>pcre[16|32]_exec()</b> to dd (any number of digits)
+  \P         pass the PCRE_PARTIAL_SOFT option to <b>pcre[16|32]_exec()</b> or <b>pcre[16|32]_dfa_exec()</b>; if used twice, pass the
+               PCRE_PARTIAL_HARD option
+  \Qdd       set the PCRE_MATCH_LIMIT_RECURSION limit to dd (any number of digits)
+  \R         pass the PCRE_DFA_RESTART option to <b>pcre[16|32]_dfa_exec()</b>
+  \S         output details of memory get/free calls during matching
+  \Y         pass the PCRE_NO_START_OPTIMIZE option to <b>pcre[16|32]_exec()</b> or <b>pcre[16|32]_dfa_exec()</b>
+  \Z         pass the PCRE_NOTEOL option to <b>pcre[16|32]_exec()</b> or <b>pcre[16|32]_dfa_exec()</b>
+  \?         pass the PCRE_NO_UTF[8|16|32]_CHECK option to <b>pcre[16|32]_exec()</b> or <b>pcre[16|32]_dfa_exec()</b>
+  \&#62;dd       start the match at offset dd (optional "-"; then any number of digits); this sets the <i>startoffset</i>
+               argument for <b>pcre[16|32]_exec()</b> or <b>pcre[16|32]_dfa_exec()</b>
+  \&#60;cr&#62;      pass the PCRE_NEWLINE_CR option to <b>pcre[16|32]_exec()</b> or <b>pcre[16|32]_dfa_exec()</b>
+  \&#60;lf&#62;      pass the PCRE_NEWLINE_LF option to <b>pcre[16|32]_exec()</b> or <b>pcre[16|32]_dfa_exec()</b>
+  \&#60;crlf&#62;    pass the PCRE_NEWLINE_CRLF option to <b>pcre[16|32]_exec()</b> or <b>pcre[16|32]_dfa_exec()</b>
+  \&#60;anycrlf&#62; pass the PCRE_NEWLINE_ANYCRLF option to <b>pcre[16|32]_exec()</b> or <b>pcre[16|32]_dfa_exec()</b>
+  \&#60;any&#62;     pass the PCRE_NEWLINE_ANY option to <b>pcre[16|32]_exec()</b> or <b>pcre[16|32]_dfa_exec()</b>
+</pre>
+The use of \x{hh...} is not dependent on the use of the <b>/8</b> modifier on
+the pattern. It is recognized always. There may be any number of hexadecimal
+digits inside the braces; invalid values provoke error messages.
+</P>
+<P>
+Note that \xhh specifies one byte rather than one character in UTF-8 mode;
+this makes it possible to construct invalid UTF-8 sequences for testing
+purposes. On the other hand, \x{hh} is interpreted as a UTF-8 character in
+UTF-8 mode, generating more than one byte if the value is greater than 127.
+When testing the 8-bit library not in UTF-8 mode, \x{hh} generates one byte
+for values less than 256, and causes an error for greater values.
+</P>
+<P>
+In UTF-16 mode, all 4-digit \x{hhhh} values are accepted. This makes it
+possible to construct invalid UTF-16 sequences for testing purposes.
+</P>
+<P>
+In UTF-32 mode, all 4- to 8-digit \x{...} values are accepted. This makes it
+possible to construct invalid UTF-32 sequences for testing purposes.
+</P>
+<P>
+The escapes that specify line ending sequences are literal strings, exactly as
+shown. No more than one newline setting should be present in any data line.
+</P>
+<P>
+A backslash followed by anything else just escapes the anything else. If
+the very last character is a backslash, it is ignored. This gives a way of
+passing an empty line as data, since a real empty line terminates the data
+input.
+</P>
+<P>
+The <b>\J</b> escape provides a way of setting the maximum stack size that is
+used by the just-in-time optimization code. It is ignored if JIT optimization
+is not being used. Providing a stack that is larger than the default 32K is
+necessary only for very complicated patterns.
+</P>
+<P>
+If \M is present, <b>pcretest</b> calls <b>pcre[16|32]_exec()</b> several times,
+with different values in the <i>match_limit</i> and <i>match_limit_recursion</i>
+fields of the <b>pcre[16|32]_extra</b> data structure, until it finds the minimum
+numbers for each parameter that allow <b>pcre[16|32]_exec()</b> to complete without
+error. Because this is testing a specific feature of the normal interpretive
+<b>pcre[16|32]_exec()</b> execution, the use of any JIT optimization that might
+have been set up by the <b>/S+</b> qualifier of <b>-s+</b> option is disabled.
+</P>
+<P>
+The <i>match_limit</i> number is a measure of the amount of backtracking
+that takes place, and checking it out can be instructive. For most simple
+matches, the number is quite small, but for patterns with very large numbers of
+matching possibilities, it can become large very quickly with increasing length
+of subject string. The <i>match_limit_recursion</i> number is a measure of how
+much stack (or, if PCRE is compiled with NO_RECURSE, how much heap) memory is
+needed to complete the match attempt.
+</P>
+<P>
+When \O is used, the value specified may be higher or lower than the size set
+by the <b>-O</b> command line option (or defaulted to 45); \O applies only to
+the call of <b>pcre[16|32]_exec()</b> for the line in which it appears.
+</P>
+<P>
+If the <b>/P</b> modifier was present on the pattern, causing the POSIX wrapper
+API to be used, the only option-setting sequences that have any effect are \B,
+\N, and \Z, causing REG_NOTBOL, REG_NOTEMPTY, and REG_NOTEOL, respectively,
+to be passed to <b>regexec()</b>.
+</P>
+<br><a name="SEC8" href="#TOC1">THE ALTERNATIVE MATCHING FUNCTION</a><br>
+<P>
+By default, <b>pcretest</b> uses the standard PCRE matching function,
+<b>pcre[16|32]_exec()</b> to match each data line. PCRE also supports an
+alternative matching function, <b>pcre[16|32]_dfa_test()</b>, which operates in a
+different way, and has some restrictions. The differences between the two
+functions are described in the
+<a href="pcrematching.html"><b>pcrematching</b></a>
+documentation.
+</P>
+<P>
+If a data line contains the \D escape sequence, or if the command line
+contains the <b>-dfa</b> option, the alternative matching function is used.
+This function finds all possible matches at a given point. If, however, the \F
+escape sequence is present in the data line, it stops after the first match is
+found. This is always the shortest possible match.
+</P>
+<br><a name="SEC9" href="#TOC1">DEFAULT OUTPUT FROM PCRETEST</a><br>
+<P>
+This section describes the output when the normal matching function,
+<b>pcre[16|32]_exec()</b>, is being used.
+</P>
+<P>
+When a match succeeds, <b>pcretest</b> outputs the list of captured substrings
+that <b>pcre[16|32]_exec()</b> returns, starting with number 0 for the string that
+matched the whole pattern. Otherwise, it outputs "No match" when the return is
+PCRE_ERROR_NOMATCH, and "Partial match:" followed by the partially matching
+substring when <b>pcre[16|32]_exec()</b> returns PCRE_ERROR_PARTIAL. (Note that
+this is the entire substring that was inspected during the partial match; it
+may include characters before the actual match start if a lookbehind assertion,
+\K, \b, or \B was involved.) For any other return, <b>pcretest</b> outputs
+the PCRE negative error number and a short descriptive phrase. If the error is
+a failed UTF string check, the offset of the start of the failing character and
+the reason code are also output, provided that the size of the output vector is
+at least two. Here is an example of an interactive <b>pcretest</b> run.
+<pre>
+  $ pcretest
+  PCRE version 8.13 2011-04-30
+
+    re&#62; /^abc(\d+)/
+  data&#62; abc123
+   0: abc123
+   1: 123
+  data&#62; xyz
+  No match
+</pre>
+Unset capturing substrings that are not followed by one that is set are not
+returned by <b>pcre[16|32]_exec()</b>, and are not shown by <b>pcretest</b>. In the
+following example, there are two capturing substrings, but when the first data
+line is matched, the second, unset substring is not shown. An "internal" unset
+substring is shown as "&#60;unset&#62;", as for the second data line.
+<pre>
+    re&#62; /(a)|(b)/
+  data&#62; a
+   0: a
+   1: a
+  data&#62; b
+   0: b
+   1: &#60;unset&#62;
+   2: b
+</pre>
+If the strings contain any non-printing characters, they are output as \xhh
+escapes if the value is less than 256 and UTF mode is not set. Otherwise they
+are output as \x{hh...} escapes. See below for the definition of non-printing
+characters. If the pattern has the <b>/+</b> modifier, the output for substring
+0 is followed by the the rest of the subject string, identified by "0+" like
+this:
+<pre>
+    re&#62; /cat/+
+  data&#62; cataract
+   0: cat
+   0+ aract
+</pre>
+If the pattern has the <b>/g</b> or <b>/G</b> modifier, the results of successive
+matching attempts are output in sequence, like this:
+<pre>
+    re&#62; /\Bi(\w\w)/g
+  data&#62; Mississippi
+   0: iss
+   1: ss
+   0: iss
+   1: ss
+   0: ipp
+   1: pp
+</pre>
+"No match" is output only if the first match attempt fails. Here is an example
+of a failure message (the offset 4 that is specified by \&#62;4 is past the end of
+the subject string):
+<pre>
+    re&#62; /xyz/
+  data&#62; xyz\&#62;4
+  Error -24 (bad offset value)
+</PRE>
+</P>
+<P>
+If any of the sequences <b>\C</b>, <b>\G</b>, or <b>\L</b> are present in a
+data line that is successfully matched, the substrings extracted by the
+convenience functions are output with C, G, or L after the string number
+instead of a colon. This is in addition to the normal full list. The string
+length (that is, the return from the extraction function) is given in
+parentheses after each string for <b>\C</b> and <b>\G</b>.
+</P>
+<P>
+Note that whereas patterns can be continued over several lines (a plain "&#62;"
+prompt is used for continuations), data lines may not. However newlines can be
+included in data by means of the \n escape (or \r, \r\n, etc., depending on
+the newline sequence setting).
+</P>
+<br><a name="SEC10" href="#TOC1">OUTPUT FROM THE ALTERNATIVE MATCHING FUNCTION</a><br>
+<P>
+When the alternative matching function, <b>pcre[16|32]_dfa_exec()</b>, is used (by
+means of the \D escape sequence or the <b>-dfa</b> command line option), the
+output consists of a list of all the matches that start at the first point in
+the subject where there is at least one match. For example:
+<pre>
+    re&#62; /(tang|tangerine|tan)/
+  data&#62; yellow tangerine\D
+   0: tangerine
+   1: tang
+   2: tan
+</pre>
+(Using the normal matching function on this data finds only "tang".) The
+longest matching string is always given first (and numbered zero). After a
+PCRE_ERROR_PARTIAL return, the output is "Partial match:", followed by the
+partially matching substring. (Note that this is the entire substring that was
+inspected during the partial match; it may include characters before the actual
+match start if a lookbehind assertion, \K, \b, or \B was involved.)
+</P>
+<P>
+If <b>/g</b> is present on the pattern, the search for further matches resumes
+at the end of the longest match. For example:
+<pre>
+    re&#62; /(tang|tangerine|tan)/g
+  data&#62; yellow tangerine and tangy sultana\D
+   0: tangerine
+   1: tang
+   2: tan
+   0: tang
+   1: tan
+   0: tan
+</pre>
+Since the matching function does not support substring capture, the escape
+sequences that are concerned with captured substrings are not relevant.
+</P>
+<br><a name="SEC11" href="#TOC1">RESTARTING AFTER A PARTIAL MATCH</a><br>
+<P>
+When the alternative matching function has given the PCRE_ERROR_PARTIAL return,
+indicating that the subject partially matched the pattern, you can restart the
+match with additional subject data by means of the \R escape sequence. For
+example:
+<pre>
+    re&#62; /^\d?\d(jan|feb|mar|apr|may|jun|jul|aug|sep|oct|nov|dec)\d\d$/
+  data&#62; 23ja\P\D
+  Partial match: 23ja
+  data&#62; n05\R\D
+   0: n05
+</pre>
+For further information about partial matching, see the
+<a href="pcrepartial.html"><b>pcrepartial</b></a>
+documentation.
+</P>
+<br><a name="SEC12" href="#TOC1">CALLOUTS</a><br>
+<P>
+If the pattern contains any callout requests, <b>pcretest</b>'s callout function
+is called during matching. This works with both matching functions. By default,
+the called function displays the callout number, the start and current
+positions in the text at the callout time, and the next pattern item to be
+tested. For example:
+<pre>
+  ---&#62;pqrabcdef
+    0    ^  ^     \d
+</pre>
+This output indicates that callout number 0 occurred for a match attempt
+starting at the fourth character of the subject string, when the pointer was at
+the seventh character of the data, and when the next pattern item was \d. Just
+one circumflex is output if the start and current positions are the same.
+</P>
+<P>
+Callouts numbered 255 are assumed to be automatic callouts, inserted as a
+result of the <b>/C</b> pattern modifier. In this case, instead of showing the
+callout number, the offset in the pattern, preceded by a plus, is output. For
+example:
+<pre>
+    re&#62; /\d?[A-E]\*/C
+  data&#62; E*
+  ---&#62;E*
+   +0 ^      \d?
+   +3 ^      [A-E]
+   +8 ^^     \*
+  +10 ^ ^
+   0: E*
+</pre>
+If a pattern contains (*MARK) items, an additional line is output whenever
+a change of latest mark is passed to the callout function. For example:
+<pre>
+    re&#62; /a(*MARK:X)bc/C
+  data&#62; abc
+  ---&#62;abc
+   +0 ^       a
+   +1 ^^      (*MARK:X)
+  +10 ^^      b
+  Latest Mark: X
+  +11 ^ ^     c
+  +12 ^  ^
+   0: abc
+</pre>
+The mark changes between matching "a" and "b", but stays the same for the rest
+of the match, so nothing more is output. If, as a result of backtracking, the
+mark reverts to being unset, the text "&#60;unset&#62;" is output.
+</P>
+<P>
+The callout function in <b>pcretest</b> returns zero (carry on matching) by
+default, but you can use a \C item in a data line (as described above) to
+change this and other parameters of the callout.
+</P>
+<P>
+Inserting callouts can be helpful when using <b>pcretest</b> to check
+complicated regular expressions. For further information about callouts, see
+the
+<a href="pcrecallout.html"><b>pcrecallout</b></a>
+documentation.
+</P>
+<br><a name="SEC13" href="#TOC1">NON-PRINTING CHARACTERS</a><br>
+<P>
+When <b>pcretest</b> is outputting text in the compiled version of a pattern,
+bytes other than 32-126 are always treated as non-printing characters are are
+therefore shown as hex escapes.
+</P>
+<P>
+When <b>pcretest</b> is outputting text that is a matched part of a subject
+string, it behaves in the same way, unless a different locale has been set for
+the pattern (using the <b>/L</b> modifier). In this case, the <b>isprint()</b>
+function to distinguish printing and non-printing characters.
+</P>
+<br><a name="SEC14" href="#TOC1">SAVING AND RELOADING COMPILED PATTERNS</a><br>
+<P>
+The facilities described in this section are not available when the POSIX
+interface to PCRE is being used, that is, when the <b>/P</b> pattern modifier is
+specified.
+</P>
+<P>
+When the POSIX interface is not in use, you can cause <b>pcretest</b> to write a
+compiled pattern to a file, by following the modifiers with &#62; and a file name.
+For example:
+<pre>
+  /pattern/im &#62;/some/file
+</pre>
+See the
+<a href="pcreprecompile.html"><b>pcreprecompile</b></a>
+documentation for a discussion about saving and re-using compiled patterns.
+Note that if the pattern was successfully studied with JIT optimization, the
+JIT data cannot be saved.
+</P>
+<P>
+The data that is written is binary. The first eight bytes are the length of the
+compiled pattern data followed by the length of the optional study data, each
+written as four bytes in big-endian order (most significant byte first). If
+there is no study data (either the pattern was not studied, or studying did not
+return any data), the second length is zero. The lengths are followed by an
+exact copy of the compiled pattern. If there is additional study data, this
+(excluding any JIT data) follows immediately after the compiled pattern. After
+writing the file, <b>pcretest</b> expects to read a new pattern.
+</P>
+<P>
+A saved pattern can be reloaded into <b>pcretest</b> by specifying &#60; and a file
+name instead of a pattern. There must be no space between &#60; and the file name,
+which must not contain a &#60; character, as otherwise <b>pcretest</b> will
+interpret the line as a pattern delimited by &#60; characters. For example:
+<pre>
+   re&#62; &#60;/some/file
+  Compiled pattern loaded from /some/file
+  No study data
+</pre>
+If the pattern was previously studied with the JIT optimization, the JIT
+information cannot be saved and restored, and so is lost. When the pattern has
+been loaded, <b>pcretest</b> proceeds to read data lines in the usual way.
+</P>
+<P>
+You can copy a file written by <b>pcretest</b> to a different host and reload it
+there, even if the new host has opposite endianness to the one on which the
+pattern was compiled. For example, you can compile on an i86 machine and run on
+a SPARC machine. When a pattern is reloaded on a host with different
+endianness, the confirmation message is changed to:
+<pre>
+  Compiled pattern (byte-inverted) loaded from /some/file
+</pre>
+The test suite contains some saved pre-compiled patterns with different
+endianness. These are reloaded using "&#60;!" instead of just "&#60;". This suppresses
+the "(byte-inverted)" text so that the output is the same on all hosts. It also
+forces debugging output once the pattern has been reloaded.
+</P>
+<P>
+File names for saving and reloading can be absolute or relative, but note that
+the shell facility of expanding a file name that starts with a tilde (~) is not
+available.
+</P>
+<P>
+The ability to save and reload files in <b>pcretest</b> is intended for testing
+and experimentation. It is not intended for production use because only a
+single pattern can be written to a file. Furthermore, there is no facility for
+supplying custom character tables for use with a reloaded pattern. If the
+original pattern was compiled with custom tables, an attempt to match a subject
+string using a reloaded pattern is likely to cause <b>pcretest</b> to crash.
+Finally, if you attempt to load a file that is not in the correct format, the
+result is undefined.
+</P>
+<br><a name="SEC15" href="#TOC1">SEE ALSO</a><br>
+<P>
+<b>pcre</b>(3), <b>pcre16</b>(3), <b>pcre32</b>(3), <b>pcreapi</b>(3),
+<b>pcrecallout</b>(3),
+<b>pcrejit</b>, <b>pcrematching</b>(3), <b>pcrepartial</b>(d),
+<b>pcrepattern</b>(3), <b>pcreprecompile</b>(3).
+</P>
+<br><a name="SEC16" href="#TOC1">AUTHOR</a><br>
+<P>
+Philip Hazel
+<br>
+University Computing Service
+<br>
+Cambridge CB2 3QH, England.
+<br>
+</P>
+<br><a name="SEC17" href="#TOC1">REVISION</a><br>
+<P>
+Last updated: 09 February 2014
+<br>
+Copyright &copy; 1997-2014 University of Cambridge.
+<br>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/html/pcreunicode.html b/libs/Pcre16/docs/doc/html/pcreunicode.html
new file mode 100644
index 0000000000..ab36bc61e3
--- /dev/null
+++ b/libs/Pcre16/docs/doc/html/pcreunicode.html
@@ -0,0 +1,262 @@
+<html>
+<head>
+<title>pcreunicode specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>pcreunicode man page</h1>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
+<p>
+This page is part of the PCRE HTML documentation. It was generated automatically
+from the original man page. If there is any nonsense in it, please consult the
+man page, in case the conversion went wrong.
+<br>
+<br><b>
+UTF-8, UTF-16, UTF-32, AND UNICODE PROPERTY SUPPORT
+</b><br>
+<P>
+As well as UTF-8 support, PCRE also supports UTF-16 (from release 8.30) and
+UTF-32 (from release 8.32), by means of two additional libraries. They can be
+built as well as, or instead of, the 8-bit library.
+</P>
+<br><b>
+UTF-8 SUPPORT
+</b><br>
+<P>
+In order process UTF-8 strings, you must build PCRE's 8-bit library with UTF
+support, and, in addition, you must call
+<a href="pcre_compile.html"><b>pcre_compile()</b></a>
+with the PCRE_UTF8 option flag, or the pattern must start with the sequence
+(*UTF8) or (*UTF). When either of these is the case, both the pattern and any
+subject strings that are matched against it are treated as UTF-8 strings
+instead of strings of individual 1-byte characters.
+</P>
+<br><b>
+UTF-16 AND UTF-32 SUPPORT
+</b><br>
+<P>
+In order process UTF-16 or UTF-32 strings, you must build PCRE's 16-bit or
+32-bit library with UTF support, and, in addition, you must call
+<a href="pcre16_compile.html"><b>pcre16_compile()</b></a>
+or
+<a href="pcre32_compile.html"><b>pcre32_compile()</b></a>
+with the PCRE_UTF16 or PCRE_UTF32 option flag, as appropriate. Alternatively,
+the pattern must start with the sequence (*UTF16), (*UTF32), as appropriate, or
+(*UTF), which can be used with either library. When UTF mode is set, both the
+pattern and any subject strings that are matched against it are treated as
+UTF-16 or UTF-32 strings instead of strings of individual 16-bit or 32-bit
+characters.
+</P>
+<br><b>
+UTF SUPPORT OVERHEAD
+</b><br>
+<P>
+If you compile PCRE with UTF support, but do not use it at run time, the
+library will be a bit bigger, but the additional run time overhead is limited
+to testing the PCRE_UTF[8|16|32] flag occasionally, so should not be very big.
+</P>
+<br><b>
+UNICODE PROPERTY SUPPORT
+</b><br>
+<P>
+If PCRE is built with Unicode character property support (which implies UTF
+support), the escape sequences \p{..}, \P{..}, and \X can be used.
+The available properties that can be tested are limited to the general
+category properties such as Lu for an upper case letter or Nd for a decimal
+number, the Unicode script names such as Arabic or Han, and the derived
+properties Any and L&. Full lists is given in the
+<a href="pcrepattern.html"><b>pcrepattern</b></a>
+and
+<a href="pcresyntax.html"><b>pcresyntax</b></a>
+documentation. Only the short names for properties are supported. For example,
+\p{L} matches a letter. Its Perl synonym, \p{Letter}, is not supported.
+Furthermore, in Perl, many properties may optionally be prefixed by "Is", for
+compatibility with Perl 5.6. PCRE does not support this.
+<a name="utf8strings"></a></P>
+<br><b>
+Validity of UTF-8 strings
+</b><br>
+<P>
+When you set the PCRE_UTF8 flag, the byte strings passed as patterns and
+subjects are (by default) checked for validity on entry to the relevant
+functions. The entire string is checked before any other processing takes
+place. From release 7.3 of PCRE, the check is according the rules of RFC 3629,
+which are themselves derived from the Unicode specification. Earlier releases
+of PCRE followed the rules of RFC 2279, which allows the full range of 31-bit
+values (0 to 0x7FFFFFFF). The current check allows only values in the range U+0
+to U+10FFFF, excluding the surrogate area. (From release 8.33 the so-called
+"non-character" code points are no longer excluded because Unicode corrigendum
+#9 makes it clear that they should not be.)
+</P>
+<P>
+Characters in the "Surrogate Area" of Unicode are reserved for use by UTF-16,
+where they are used in pairs to encode codepoints with values greater than
+0xFFFF. The code points that are encoded by UTF-16 pairs are available
+independently in the UTF-8 and UTF-32 encodings. (In other words, the whole
+surrogate thing is a fudge for UTF-16 which unfortunately messes up UTF-8 and
+UTF-32.)
+</P>
+<P>
+If an invalid UTF-8 string is passed to PCRE, an error return is given. At
+compile time, the only additional information is the offset to the first byte
+of the failing character. The run-time functions <b>pcre_exec()</b> and
+<b>pcre_dfa_exec()</b> also pass back this information, as well as a more
+detailed reason code if the caller has provided memory in which to do this.
+</P>
+<P>
+In some situations, you may already know that your strings are valid, and
+therefore want to skip these checks in order to improve performance, for
+example in the case of a long subject string that is being scanned repeatedly.
+If you set the PCRE_NO_UTF8_CHECK flag at compile time or at run time, PCRE
+assumes that the pattern or subject it is given (respectively) contains only
+valid UTF-8 codes. In this case, it does not diagnose an invalid UTF-8 string.
+</P>
+<P>
+Note that passing PCRE_NO_UTF8_CHECK to <b>pcre_compile()</b> just disables the
+check for the pattern; it does not also apply to subject strings. If you want
+to disable the check for a subject string you must pass this option to
+<b>pcre_exec()</b> or <b>pcre_dfa_exec()</b>.
+</P>
+<P>
+If you pass an invalid UTF-8 string when PCRE_NO_UTF8_CHECK is set, the result
+is undefined and your program may crash.
+<a name="utf16strings"></a></P>
+<br><b>
+Validity of UTF-16 strings
+</b><br>
+<P>
+When you set the PCRE_UTF16 flag, the strings of 16-bit data units that are
+passed as patterns and subjects are (by default) checked for validity on entry
+to the relevant functions. Values other than those in the surrogate range
+U+D800 to U+DFFF are independent code points. Values in the surrogate range
+must be used in pairs in the correct manner.
+</P>
+<P>
+If an invalid UTF-16 string is passed to PCRE, an error return is given. At
+compile time, the only additional information is the offset to the first data
+unit of the failing character. The run-time functions <b>pcre16_exec()</b> and
+<b>pcre16_dfa_exec()</b> also pass back this information, as well as a more
+detailed reason code if the caller has provided memory in which to do this.
+</P>
+<P>
+In some situations, you may already know that your strings are valid, and
+therefore want to skip these checks in order to improve performance. If you set
+the PCRE_NO_UTF16_CHECK flag at compile time or at run time, PCRE assumes that
+the pattern or subject it is given (respectively) contains only valid UTF-16
+sequences. In this case, it does not diagnose an invalid UTF-16 string.
+However, if an invalid string is passed, the result is undefined.
+<a name="utf32strings"></a></P>
+<br><b>
+Validity of UTF-32 strings
+</b><br>
+<P>
+When you set the PCRE_UTF32 flag, the strings of 32-bit data units that are
+passed as patterns and subjects are (by default) checked for validity on entry
+to the relevant functions.  This check allows only values in the range U+0
+to U+10FFFF, excluding the surrogate area U+D800 to U+DFFF.
+</P>
+<P>
+If an invalid UTF-32 string is passed to PCRE, an error return is given. At
+compile time, the only additional information is the offset to the first data
+unit of the failing character. The run-time functions <b>pcre32_exec()</b> and
+<b>pcre32_dfa_exec()</b> also pass back this information, as well as a more
+detailed reason code if the caller has provided memory in which to do this.
+</P>
+<P>
+In some situations, you may already know that your strings are valid, and
+therefore want to skip these checks in order to improve performance. If you set
+the PCRE_NO_UTF32_CHECK flag at compile time or at run time, PCRE assumes that
+the pattern or subject it is given (respectively) contains only valid UTF-32
+sequences. In this case, it does not diagnose an invalid UTF-32 string.
+However, if an invalid string is passed, the result is undefined.
+</P>
+<br><b>
+General comments about UTF modes
+</b><br>
+<P>
+1. Codepoints less than 256 can be specified in patterns by either braced or
+unbraced hexadecimal escape sequences (for example, \x{b3} or \xb3). Larger
+values have to use braced sequences.
+</P>
+<P>
+2. Octal numbers up to \777 are recognized, and in UTF-8 mode they match
+two-byte characters for values greater than \177.
+</P>
+<P>
+3. Repeat quantifiers apply to complete UTF characters, not to individual
+data units, for example: \x{100}{3}.
+</P>
+<P>
+4. The dot metacharacter matches one UTF character instead of a single data
+unit.
+</P>
+<P>
+5. The escape sequence \C can be used to match a single byte in UTF-8 mode, or
+a single 16-bit data unit in UTF-16 mode, or a single 32-bit data unit in
+UTF-32 mode, but its use can lead to some strange effects because it breaks up
+multi-unit characters (see the description of \C in the
+<a href="pcrepattern.html"><b>pcrepattern</b></a>
+documentation). The use of \C is not supported in the alternative matching
+function <b>pcre[16|32]_dfa_exec()</b>, nor is it supported in UTF mode by the
+JIT optimization of <b>pcre[16|32]_exec()</b>. If JIT optimization is requested
+for a UTF pattern that contains \C, it will not succeed, and so the matching
+will be carried out by the normal interpretive function.
+</P>
+<P>
+6. The character escapes \b, \B, \d, \D, \s, \S, \w, and \W correctly
+test characters of any code value, but, by default, the characters that PCRE
+recognizes as digits, spaces, or word characters remain the same set as in
+non-UTF mode, all with values less than 256. This remains true even when PCRE
+is built to include Unicode property support, because to do otherwise would
+slow down PCRE in many common cases. Note in particular that this applies to
+\b and \B, because they are defined in terms of \w and \W. If you really
+want to test for a wider sense of, say, "digit", you can use explicit Unicode
+property tests such as \p{Nd}. Alternatively, if you set the PCRE_UCP option,
+the way that the character escapes work is changed so that Unicode properties
+are used to determine which characters match. There are more details in the
+section on
+<a href="pcrepattern.html#genericchartypes">generic character types</a>
+in the
+<a href="pcrepattern.html"><b>pcrepattern</b></a>
+documentation.
+</P>
+<P>
+7. Similarly, characters that match the POSIX named character classes are all
+low-valued characters, unless the PCRE_UCP option is set.
+</P>
+<P>
+8. However, the horizontal and vertical white space matching escapes (\h, \H,
+\v, and \V) do match all the appropriate Unicode characters, whether or not
+PCRE_UCP is set.
+</P>
+<P>
+9. Case-insensitive matching applies only to characters whose values are less
+than 128, unless PCRE is built with Unicode property support. A few Unicode
+characters such as Greek sigma have more than two codepoints that are
+case-equivalent. Up to and including PCRE release 8.31, only one-to-one case
+mappings were supported, but later releases (with Unicode property support) do
+treat as case-equivalent all versions of characters such as Greek sigma.
+</P>
+<br><b>
+AUTHOR
+</b><br>
+<P>
+Philip Hazel
+<br>
+University Computing Service
+<br>
+Cambridge CB2 3QH, England.
+<br>
+</P>
+<br><b>
+REVISION
+</b><br>
+<P>
+Last updated: 27 February 2013
+<br>
+Copyright &copy; 1997-2013 University of Cambridge.
+<br>
+<p>
+Return to the <a href="index.html">PCRE index page</a>.
+</p>
diff --git a/libs/Pcre16/docs/doc/index.html.src b/libs/Pcre16/docs/doc/index.html.src
new file mode 100644
index 0000000000..887f4d7507
--- /dev/null
+++ b/libs/Pcre16/docs/doc/index.html.src
@@ -0,0 +1,185 @@
+<html>
+<!-- This is a manually maintained file that is the root of the HTML version of 
+     the PCRE documentation. When the HTML documents are built from the man 
+     page versions, the entire doc/html directory is emptied, this file is then 
+     copied into doc/html/index.html, and the remaining files therein are 
+     created by the 132html script.
+-->      
+<head>
+<title>PCRE specification</title>
+</head>
+<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
+<h1>Perl-compatible Regular Expressions (PCRE)</h1>
+<p>
+The HTML documentation for PCRE consists of a number of pages that are listed
+below in alphabetical order. If you are new to PCRE, please read the first one
+first.
+</p>
+
+<table>
+<tr><td><a href="pcre.html">pcre</a></td>
+    <td>&nbsp;&nbsp;Introductory page</td></tr>
+
+<tr><td><a href="pcre-config.html">pcre-config</a></td>
+    <td>&nbsp;&nbsp;Information about the installation configuration</td></tr>
+
+<tr><td><a href="pcre16.html">pcre16</a></td>
+    <td>&nbsp;&nbsp;Discussion of the 16-bit PCRE library</td></tr>
+
+<tr><td><a href="pcre32.html">pcre32</a></td>
+    <td>&nbsp;&nbsp;Discussion of the 32-bit PCRE library</td></tr>
+
+<tr><td><a href="pcreapi.html">pcreapi</a></td>
+    <td>&nbsp;&nbsp;PCRE's native API</td></tr>
+
+<tr><td><a href="pcrebuild.html">pcrebuild</a></td>
+    <td>&nbsp;&nbsp;Building PCRE</td></tr>
+
+<tr><td><a href="pcrecallout.html">pcrecallout</a></td>
+    <td>&nbsp;&nbsp;The <i>callout</i> facility</td></tr>
+
+<tr><td><a href="pcrecompat.html">pcrecompat</a></td>
+    <td>&nbsp;&nbsp;Compability with Perl</td></tr>
+
+<tr><td><a href="pcrecpp.html">pcrecpp</a></td>
+    <td>&nbsp;&nbsp;The C++ wrapper for the PCRE library</td></tr>
+
+<tr><td><a href="pcredemo.html">pcredemo</a></td>
+    <td>&nbsp;&nbsp;A demonstration C program that uses the PCRE library</td></tr>
+
+<tr><td><a href="pcregrep.html">pcregrep</a></td>
+    <td>&nbsp;&nbsp;The <b>pcregrep</b> command</td></tr>
+
+<tr><td><a href="pcrejit.html">pcrejit</a></td>
+    <td>&nbsp;&nbsp;Discussion of the just-in-time optimization support</td></tr>
+
+<tr><td><a href="pcrelimits.html">pcrelimits</a></td>
+    <td>&nbsp;&nbsp;Details of size and other limits</td></tr>
+
+<tr><td><a href="pcrematching.html">pcrematching</a></td>
+    <td>&nbsp;&nbsp;Discussion of the two matching algorithms</td></tr>
+
+<tr><td><a href="pcrepartial.html">pcrepartial</a></td>
+    <td>&nbsp;&nbsp;Using PCRE for partial matching</td></tr>
+
+<tr><td><a href="pcrepattern.html">pcrepattern</a></td>
+    <td>&nbsp;&nbsp;Specification of the regular expressions supported by PCRE</td></tr>
+
+<tr><td><a href="pcreperform.html">pcreperform</a></td>
+    <td>&nbsp;&nbsp;Some comments on performance</td></tr>
+
+<tr><td><a href="pcreposix.html">pcreposix</a></td>
+    <td>&nbsp;&nbsp;The POSIX API to the PCRE 8-bit library</td></tr>
+
+<tr><td><a href="pcreprecompile.html">pcreprecompile</a></td>
+    <td>&nbsp;&nbsp;How to save and re-use compiled patterns</td></tr>
+
+<tr><td><a href="pcresample.html">pcresample</a></td>
+    <td>&nbsp;&nbsp;Discussion of the pcredemo program</td></tr>
+
+<tr><td><a href="pcrestack.html">pcrestack</a></td>
+    <td>&nbsp;&nbsp;Discussion of PCRE's stack usage</td></tr>
+
+<tr><td><a href="pcresyntax.html">pcresyntax</a></td>
+    <td>&nbsp;&nbsp;Syntax quick-reference summary</td></tr>
+
+<tr><td><a href="pcretest.html">pcretest</a></td>
+    <td>&nbsp;&nbsp;The <b>pcretest</b> command for testing PCRE</td></tr>
+
+<tr><td><a href="pcreunicode.html">pcreunicode</a></td>
+    <td>&nbsp;&nbsp;Discussion of Unicode and UTF-8/UTF-16/UTF-32 support</td></tr>
+</table>
+
+<p>
+There are also individual pages that summarize the interface for each function
+in the library. There is a single page for each triple of 8-bit/16-bit/32-bit
+functions.
+</p>
+
+<table>    
+
+<tr><td><a href="pcre_assign_jit_stack.html">pcre_assign_jit_stack</a></td>
+    <td>&nbsp;&nbsp;Assign stack for JIT matching</td></tr>
+
+<tr><td><a href="pcre_compile.html">pcre_compile</a></td>
+    <td>&nbsp;&nbsp;Compile a regular expression</td></tr>
+
+<tr><td><a href="pcre_compile2.html">pcre_compile2</a></td>
+    <td>&nbsp;&nbsp;Compile a regular expression (alternate interface)</td></tr>
+
+<tr><td><a href="pcre_config.html">pcre_config</a></td>
+    <td>&nbsp;&nbsp;Show build-time configuration options</td></tr>
+
+<tr><td><a href="pcre_copy_named_substring.html">pcre_copy_named_substring</a></td>
+    <td>&nbsp;&nbsp;Extract named substring into given buffer</td></tr>
+
+<tr><td><a href="pcre_copy_substring.html">pcre_copy_substring</a></td>
+    <td>&nbsp;&nbsp;Extract numbered substring into given buffer</td></tr>
+
+<tr><td><a href="pcre_dfa_exec.html">pcre_dfa_exec</a></td>
+    <td>&nbsp;&nbsp;Match a compiled pattern to a subject string
+    (DFA algorithm; <i>not</i> Perl compatible)</td></tr>
+
+<tr><td><a href="pcre_exec.html">pcre_exec</a></td>
+    <td>&nbsp;&nbsp;Match a compiled pattern to a subject string
+    (Perl compatible)</td></tr>
+
+<tr><td><a href="pcre_free_study.html">pcre_free_study</a></td>
+    <td>&nbsp;&nbsp;Free study data</td></tr>
+
+<tr><td><a href="pcre_free_substring.html">pcre_free_substring</a></td>
+    <td>&nbsp;&nbsp;Free extracted substring</td></tr>
+
+<tr><td><a href="pcre_free_substring_list.html">pcre_free_substring_list</a></td>
+    <td>&nbsp;&nbsp;Free list of extracted substrings</td></tr>
+
+<tr><td><a href="pcre_fullinfo.html">pcre_fullinfo</a></td>
+    <td>&nbsp;&nbsp;Extract information about a pattern</td></tr>
+
+<tr><td><a href="pcre_get_named_substring.html">pcre_get_named_substring</a></td>
+    <td>&nbsp;&nbsp;Extract named substring into new memory</td></tr>
+
+<tr><td><a href="pcre_get_stringnumber.html">pcre_get_stringnumber</a></td>
+    <td>&nbsp;&nbsp;Convert captured string name to number</td></tr>
+
+<tr><td><a href="pcre_get_stringtable_entries.html">pcre_get_stringtable_entries</a></td>
+    <td>&nbsp;&nbsp;Find table entries for given string name</td></tr>
+
+<tr><td><a href="pcre_get_substring.html">pcre_get_substring</a></td>
+    <td>&nbsp;&nbsp;Extract numbered substring into new memory</td></tr>
+
+<tr><td><a href="pcre_get_substring_list.html">pcre_get_substring_list</a></td>
+    <td>&nbsp;&nbsp;Extract all substrings into new memory</td></tr>
+
+<tr><td><a href="pcre_jit_exec.html">pcre_jit_exec</a></td>
+    <td>&nbsp;&nbsp;Fast path interface to JIT matching</td></tr>
+
+<tr><td><a href="pcre_jit_stack_alloc.html">pcre_jit_stack_alloc</a></td>
+    <td>&nbsp;&nbsp;Create a stack for JIT matching</td></tr>
+
+<tr><td><a href="pcre_jit_stack_free.html">pcre_jit_stack_free</a></td>
+    <td>&nbsp;&nbsp;Free a JIT matching stack</td></tr>
+
+<tr><td><a href="pcre_maketables.html">pcre_maketables</a></td>
+    <td>&nbsp;&nbsp;Build character tables in current locale</td></tr>
+    
+<tr><td><a href="pcre_pattern_to_host_byte_order.html">pcre_pattern_to_host_byte_order</a></td>
+    <td>&nbsp;&nbsp;Convert compiled pattern to host byte order if necessary</td></tr>
+
+<tr><td><a href="pcre_refcount.html">pcre_refcount</a></td>
+    <td>&nbsp;&nbsp;Maintain reference count in compiled pattern</td></tr>
+
+<tr><td><a href="pcre_study.html">pcre_study</a></td>
+    <td>&nbsp;&nbsp;Study a compiled pattern</td></tr>
+
+<tr><td><a href="pcre_utf16_to_host_byte_order.html">pcre_utf16_to_host_byte_order</a></td>
+    <td>&nbsp;&nbsp;Convert UTF-16 string to host byte order if necessary</td></tr>
+
+<tr><td><a href="pcre_utf32_to_host_byte_order.html">pcre_utf32_to_host_byte_order</a></td>
+    <td>&nbsp;&nbsp;Convert UTF-32 string to host byte order if necessary</td></tr>
+
+<tr><td><a href="pcre_version.html">pcre_version</a></td>
+    <td>&nbsp;&nbsp;Return PCRE version and release date</td></tr>
+</table>
+
+</html>
diff --git a/libs/Pcre16/docs/doc/pcre-config.1 b/libs/Pcre16/docs/doc/pcre-config.1
new file mode 100644
index 0000000000..52eb4fb226
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcre-config.1
@@ -0,0 +1,92 @@
+.TH PCRE-CONFIG 1 "01 January 2012" "PCRE 8.30"
+.SH NAME
+pcre-config - program to return PCRE configuration
+.SH SYNOPSIS
+.rs
+.sp
+.nf
+.B pcre-config  [--prefix] [--exec-prefix] [--version] [--libs]
+.B "            [--libs16] [--libs32] [--libs-cpp] [--libs-posix]"
+.B "            [--cflags] [--cflags-posix]"
+.fi
+.
+.
+.SH DESCRIPTION
+.rs
+.sp
+\fBpcre-config\fP returns the configuration of the installed PCRE
+libraries and the options required to compile a program to use them. Some of
+the options apply only to the 8-bit, or 16-bit, or 32-bit libraries,
+respectively, and are
+not available if only one of those libraries has been built. If an unavailable
+option is encountered, the "usage" information is output.
+.
+.
+.SH OPTIONS
+.rs
+.TP 10
+\fB--prefix\fP
+Writes the directory prefix used in the PCRE installation for architecture
+independent files (\fI/usr\fP on many systems, \fI/usr/local\fP on some
+systems) to the standard output.
+.TP 10
+\fB--exec-prefix\fP
+Writes the directory prefix used in the PCRE installation for architecture
+dependent files (normally the same as \fB--prefix\fP) to the standard output.
+.TP 10
+\fB--version\fP
+Writes the version number of the installed PCRE libraries to the standard
+output.
+.TP 10
+\fB--libs\fP
+Writes to the standard output the command line options required to link
+with the 8-bit PCRE library (\fB-lpcre\fP on many systems).
+.TP 10
+\fB--libs16\fP
+Writes to the standard output the command line options required to link
+with the 16-bit PCRE library (\fB-lpcre16\fP on many systems).
+.TP 10
+\fB--libs32\fP
+Writes to the standard output the command line options required to link
+with the 32-bit PCRE library (\fB-lpcre32\fP on many systems).
+.TP 10
+\fB--libs-cpp\fP
+Writes to the standard output the command line options required to link with
+PCRE's C++ wrapper library (\fB-lpcrecpp\fP \fB-lpcre\fP on many
+systems).
+.TP 10
+\fB--libs-posix\fP
+Writes to the standard output the command line options required to link with
+PCRE's POSIX API wrapper library (\fB-lpcreposix\fP \fB-lpcre\fP on many
+systems).
+.TP 10
+\fB--cflags\fP
+Writes to the standard output the command line options required to compile
+files that use PCRE (this may include some \fB-I\fP options, but is blank on
+many systems).
+.TP 10
+\fB--cflags-posix\fP
+Writes to the standard output the command line options required to compile
+files that use PCRE's POSIX API wrapper library (this may include some \fB-I\fP
+options, but is blank on many systems).
+.
+.
+.SH "SEE ALSO"
+.rs
+.sp
+\fBpcre(3)\fP
+.
+.
+.SH AUTHOR
+.rs
+.sp
+This manual page was originally written by Mark Baker for the Debian GNU/Linux
+system. It has been subsequently revised as a generic PCRE man page.
+.
+.
+.SH REVISION
+.rs
+.sp
+.nf
+Last updated: 24 June 2012
+.fi
diff --git a/libs/Pcre16/docs/doc/pcre-config.txt b/libs/Pcre16/docs/doc/pcre-config.txt
new file mode 100644
index 0000000000..8503ab0ef0
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcre-config.txt
@@ -0,0 +1,86 @@
+PCRE-CONFIG(1)              General Commands Manual             PCRE-CONFIG(1)
+
+
+
+NAME
+       pcre-config - program to return PCRE configuration
+
+SYNOPSIS
+
+       pcre-config [--prefix] [--exec-prefix] [--version] [--libs]
+                   [--libs16] [--libs32] [--libs-cpp] [--libs-posix]
+                   [--cflags] [--cflags-posix]
+
+
+DESCRIPTION
+
+       pcre-config  returns  the configuration of the installed PCRE libraries
+       and the options required to compile a program to use them. Some of  the
+       options  apply  only  to  the  8-bit,  or  16-bit, or 32-bit libraries,
+       respectively, and are not available if only one of those libraries  has
+       been built. If an unavailable option is encountered, the "usage" infor-
+       mation is output.
+
+
+OPTIONS
+
+       --prefix  Writes the directory prefix used in the PCRE installation for
+                 architecture   independent   files  (/usr  on  many  systems,
+                 /usr/local on some systems) to the standard output.
+
+       --exec-prefix
+                 Writes the directory prefix used in the PCRE installation for
+                 architecture  dependent files (normally the same as --prefix)
+                 to the standard output.
+
+       --version Writes the version number of the installed PCRE libraries  to
+                 the standard output.
+
+       --libs    Writes  to  the  standard  output  the  command  line options
+                 required to link with the 8-bit PCRE library (-lpcre on  many
+                 systems).
+
+       --libs16  Writes  to  the  standard  output  the  command  line options
+                 required to link with the 16-bit PCRE  library  (-lpcre16  on
+                 many systems).
+
+       --libs32  Writes  to  the  standard  output  the  command  line options
+                 required to link with the 32-bit PCRE  library  (-lpcre32  on
+                 many systems).
+
+       --libs-cpp
+                 Writes  to  the  standard  output  the  command  line options
+                 required to link with PCRE's C++ wrapper  library  (-lpcrecpp
+                 -lpcre on many systems).
+
+       --libs-posix
+                 Writes  to  the  standard  output  the  command  line options
+                 required to  link  with  PCRE's  POSIX  API  wrapper  library
+                 (-lpcreposix -lpcre on many systems).
+
+       --cflags  Writes  to  the  standard  output  the  command  line options
+                 required to compile files that use  PCRE  (this  may  include
+                 some -I options, but is blank on many systems).
+
+       --cflags-posix
+                 Writes  to  the  standard  output  the  command  line options
+                 required to compile files that use PCRE's POSIX  API  wrapper
+                 library  (this  may  include some -I options, but is blank on
+                 many systems).
+
+
+SEE ALSO
+
+       pcre(3)
+
+
+AUTHOR
+
+       This manual page was originally written by Mark Baker  for  the  Debian
+       GNU/Linux  system.  It  has been subsequently revised as a generic PCRE
+       man page.
+
+
+REVISION
+
+       Last updated: 24 June 2012
diff --git a/libs/Pcre16/docs/doc/pcre.3 b/libs/Pcre16/docs/doc/pcre.3
new file mode 100644
index 0000000000..4eda404ccf
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcre.3
@@ -0,0 +1,218 @@
+.TH PCRE 3 "08 January 2014" "PCRE 8.35"
+.SH NAME
+PCRE - Perl-compatible regular expressions
+.SH INTRODUCTION
+.rs
+.sp
+The PCRE library is a set of functions that implement regular expression
+pattern matching using the same syntax and semantics as Perl, with just a few
+differences. Some features that appeared in Python and PCRE before they
+appeared in Perl are also available using the Python syntax, there is some
+support for one or two .NET and Oniguruma syntax items, and there is an option
+for requesting some minor changes that give better JavaScript compatibility.
+.P
+Starting with release 8.30, it is possible to compile two separate PCRE
+libraries: the original, which supports 8-bit character strings (including
+UTF-8 strings), and a second library that supports 16-bit character strings
+(including UTF-16 strings). The build process allows either one or both to be
+built. The majority of the work to make this possible was done by Zoltan
+Herczeg.
+.P
+Starting with release 8.32 it is possible to compile a third separate PCRE
+library that supports 32-bit character strings (including UTF-32 strings). The
+build process allows any combination of the 8-, 16- and 32-bit libraries. The
+work to make this possible was done by Christian Persch.
+.P
+The three libraries contain identical sets of functions, except that the names
+in the 16-bit library start with \fBpcre16_\fP instead of \fBpcre_\fP, and the
+names in the 32-bit library start with \fBpcre32_\fP instead of \fBpcre_\fP. To
+avoid over-complication and reduce the documentation maintenance load, most of
+the documentation describes the 8-bit library, with the differences for the
+16-bit and 32-bit libraries described separately in the
+.\" HREF
+\fBpcre16\fP
+and
+.\" HREF
+\fBpcre32\fP
+.\"
+pages. References to functions or structures of the form \fIpcre[16|32]_xxx\fP
+should be read as meaning "\fIpcre_xxx\fP when using the 8-bit library,
+\fIpcre16_xxx\fP when using the 16-bit library, or \fIpcre32_xxx\fP when using
+the 32-bit library".
+.P
+The current implementation of PCRE corresponds approximately with Perl 5.12,
+including support for UTF-8/16/32 encoded strings and Unicode general category
+properties. However, UTF-8/16/32 and Unicode support has to be explicitly
+enabled; it is not the default. The Unicode tables correspond to Unicode
+release 6.3.0.
+.P
+In addition to the Perl-compatible matching function, PCRE contains an
+alternative function that matches the same compiled patterns in a different
+way. In certain circumstances, the alternative function has some advantages.
+For a discussion of the two matching algorithms, see the
+.\" HREF
+\fBpcrematching\fP
+.\"
+page.
+.P
+PCRE is written in C and released as a C library. A number of people have
+written wrappers and interfaces of various kinds. In particular, Google Inc.
+have provided a comprehensive C++ wrapper for the 8-bit library. This is now
+included as part of the PCRE distribution. The
+.\" HREF
+\fBpcrecpp\fP
+.\"
+page has details of this interface. Other people's contributions can be found
+in the \fIContrib\fP directory at the primary FTP site, which is:
+.sp
+.\" HTML <a href="ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre">
+.\" </a>
+ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre
+.\"
+.P
+Details of exactly which Perl regular expression features are and are not
+supported by PCRE are given in separate documents. See the
+.\" HREF
+\fBpcrepattern\fP
+.\"
+and
+.\" HREF
+\fBpcrecompat\fP
+.\"
+pages. There is a syntax summary in the
+.\" HREF
+\fBpcresyntax\fP
+.\"
+page.
+.P
+Some features of PCRE can be included, excluded, or changed when the library is
+built. The
+.\" HREF
+\fBpcre_config()\fP
+.\"
+function makes it possible for a client to discover which features are
+available. The features themselves are described in the
+.\" HREF
+\fBpcrebuild\fP
+.\"
+page. Documentation about building PCRE for various operating systems can be
+found in the
+.\" HTML <a href="README.txt">
+.\" </a>
+\fBREADME\fP
+.\"
+and
+.\" HTML <a href="NON-AUTOTOOLS-BUILD.txt">
+.\" </a>
+\fBNON-AUTOTOOLS_BUILD\fP
+.\"
+files in the source distribution.
+.P
+The libraries contains a number of undocumented internal functions and data
+tables that are used by more than one of the exported external functions, but
+which are not intended for use by external callers. Their names all begin with
+"_pcre_" or "_pcre16_" or "_pcre32_", which hopefully will not provoke any name
+clashes. In some environments, it is possible to control which external symbols
+are exported when a shared library is built, and in these cases the
+undocumented symbols are not exported.
+.
+.
+.SH "SECURITY CONSIDERATIONS"
+.rs
+.sp
+If you are using PCRE in a non-UTF application that permits users to supply
+arbitrary patterns for compilation, you should be aware of a feature that
+allows users to turn on UTF support from within a pattern, provided that PCRE
+was built with UTF support. For example, an 8-bit pattern that begins with
+"(*UTF8)" or "(*UTF)" turns on UTF-8 mode, which interprets patterns and
+subjects as strings of UTF-8 characters instead of individual 8-bit characters.
+This causes both the pattern and any data against which it is matched to be
+checked for UTF-8 validity. If the data string is very long, such a check might
+use sufficiently many resources as to cause your application to lose
+performance.
+.P
+One way of guarding against this possibility is to use the
+\fBpcre_fullinfo()\fP function to check the compiled pattern's options for UTF.
+Alternatively, from release 8.33, you can set the PCRE_NEVER_UTF option at
+compile time. This causes an compile time error if a pattern contains a
+UTF-setting sequence.
+.P
+If your application is one that supports UTF, be aware that validity checking
+can take time. If the same data string is to be matched many times, you can use
+the PCRE_NO_UTF[8|16|32]_CHECK option for the second and subsequent matches to
+save redundant checks.
+.P
+Another way that performance can be hit is by running a pattern that has a very
+large search tree against a string that will never match. Nested unlimited
+repeats in a pattern are a common example. PCRE provides some protection
+against this: see the PCRE_EXTRA_MATCH_LIMIT feature in the
+.\" HREF
+\fBpcreapi\fP
+.\"
+page.
+.
+.
+.SH "USER DOCUMENTATION"
+.rs
+.sp
+The user documentation for PCRE comprises a number of different sections. In
+the "man" format, each of these is a separate "man page". In the HTML format,
+each is a separate page, linked from the index page. In the plain text format,
+the descriptions of the \fBpcregrep\fP and \fBpcretest\fP programs are in files
+called \fBpcregrep.txt\fP and \fBpcretest.txt\fP, respectively. The remaining
+sections, except for the \fBpcredemo\fP section (which is a program listing),
+are concatenated in \fBpcre.txt\fP, for ease of searching. The sections are as
+follows:
+.sp
+  pcre              this document
+  pcre-config       show PCRE installation configuration information
+  pcre16            details of the 16-bit library
+  pcre32            details of the 32-bit library
+  pcreapi           details of PCRE's native C API
+  pcrebuild         building PCRE
+  pcrecallout       details of the callout feature
+  pcrecompat        discussion of Perl compatibility
+  pcrecpp           details of the C++ wrapper for the 8-bit library
+  pcredemo          a demonstration C program that uses PCRE
+  pcregrep          description of the \fBpcregrep\fP command (8-bit only)
+  pcrejit           discussion of the just-in-time optimization support
+  pcrelimits        details of size and other limits
+  pcrematching      discussion of the two matching algorithms
+  pcrepartial       details of the partial matching facility
+.\" JOIN
+  pcrepattern       syntax and semantics of supported
+                      regular expressions
+  pcreperform       discussion of performance issues
+  pcreposix         the POSIX-compatible C API for the 8-bit library
+  pcreprecompile    details of saving and re-using precompiled patterns
+  pcresample        discussion of the pcredemo program
+  pcrestack         discussion of stack usage
+  pcresyntax        quick syntax reference
+  pcretest          description of the \fBpcretest\fP testing command
+  pcreunicode       discussion of Unicode and UTF-8/16/32 support
+.sp
+In the "man" and HTML formats, there is also a short page for each C library
+function, listing its arguments and results.
+.
+.
+.SH AUTHOR
+.rs
+.sp
+.nf
+Philip Hazel
+University Computing Service
+Cambridge CB2 3QH, England.
+.fi
+.P
+Putting an actual email address here seems to have been a spam magnet, so I've
+taken it away. If you want to email me, use my two initials, followed by the
+two digits 10, at the domain cam.ac.uk.
+.
+.
+.SH REVISION
+.rs
+.sp
+.nf
+Last updated: 08 January 2014
+Copyright (c) 1997-2014 University of Cambridge.
+.fi
diff --git a/libs/Pcre16/docs/doc/pcre.txt b/libs/Pcre16/docs/doc/pcre.txt
new file mode 100644
index 0000000000..14cbb8bf2b
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcre.txt
@@ -0,0 +1,10423 @@
+-----------------------------------------------------------------------------
+This file contains a concatenation of the PCRE man pages, converted to plain
+text format for ease of searching with a text editor, or for use on systems
+that do not have a man page processor. The small individual files that give
+synopses of each function in the library have not been included. Neither has
+the pcredemo program. There are separate text files for the pcregrep and
+pcretest commands.
+-----------------------------------------------------------------------------
+
+
+PCRE(3)                    Library Functions Manual                    PCRE(3)
+
+
+
+NAME
+       PCRE - Perl-compatible regular expressions
+
+INTRODUCTION
+
+       The  PCRE  library is a set of functions that implement regular expres-
+       sion pattern matching using the same syntax and semantics as Perl, with
+       just  a few differences. Some features that appeared in Python and PCRE
+       before they appeared in Perl are also available using the  Python  syn-
+       tax,  there  is  some  support for one or two .NET and Oniguruma syntax
+       items, and there is an option for requesting some  minor  changes  that
+       give better JavaScript compatibility.
+
+       Starting with release 8.30, it is possible to compile two separate PCRE
+       libraries:  the  original,  which  supports  8-bit  character   strings
+       (including  UTF-8  strings),  and a second library that supports 16-bit
+       character strings (including UTF-16 strings). The build process  allows
+       either  one  or both to be built. The majority of the work to make this
+       possible was done by Zoltan Herczeg.
+
+       Starting with release 8.32 it is possible to compile a  third  separate
+       PCRE  library  that supports 32-bit character strings (including UTF-32
+       strings). The build process allows any combination of the 8-,  16-  and
+       32-bit  libraries. The work to make this possible was done by Christian
+       Persch.
+
+       The three libraries contain identical sets of  functions,  except  that
+       the  names  in  the 16-bit library start with pcre16_ instead of pcre_,
+       and the names in the 32-bit  library  start  with  pcre32_  instead  of
+       pcre_.  To avoid over-complication and reduce the documentation mainte-
+       nance load, most of the documentation describes the 8-bit library, with
+       the  differences  for  the  16-bit and 32-bit libraries described sepa-
+       rately in the pcre16 and  pcre32  pages.  References  to  functions  or
+       structures  of  the  form  pcre[16|32]_xxx  should  be  read as meaning
+       "pcre_xxx when using the  8-bit  library,  pcre16_xxx  when  using  the
+       16-bit library, or pcre32_xxx when using the 32-bit library".
+
+       The  current implementation of PCRE corresponds approximately with Perl
+       5.12, including support for UTF-8/16/32  encoded  strings  and  Unicode
+       general  category  properties. However, UTF-8/16/32 and Unicode support
+       has to be explicitly enabled; it is not the default. The Unicode tables
+       correspond to Unicode release 6.3.0.
+
+       In  addition to the Perl-compatible matching function, PCRE contains an
+       alternative function that matches the same compiled patterns in a  dif-
+       ferent way. In certain circumstances, the alternative function has some
+       advantages.  For a discussion of the two matching algorithms,  see  the
+       pcrematching page.
+
+       PCRE  is  written  in C and released as a C library. A number of people
+       have written wrappers and interfaces of various kinds.  In  particular,
+       Google  Inc.   have  provided a comprehensive C++ wrapper for the 8-bit
+       library. This is now included as part of  the  PCRE  distribution.  The
+       pcrecpp  page  has  details of this interface. Other people's contribu-
+       tions can be found in the Contrib directory at the  primary  FTP  site,
+       which is:
+
+       ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre
+
+       Details  of  exactly which Perl regular expression features are and are
+       not supported by PCRE are given in separate documents. See the pcrepat-
+       tern  and pcrecompat pages. There is a syntax summary in the pcresyntax
+       page.
+
+       Some features of PCRE can be included, excluded, or  changed  when  the
+       library  is  built.  The pcre_config() function makes it possible for a
+       client to discover which features are  available.  The  features  them-
+       selves  are described in the pcrebuild page. Documentation about build-
+       ing PCRE for various operating systems can be found in the  README  and
+       NON-AUTOTOOLS_BUILD files in the source distribution.
+
+       The  libraries contains a number of undocumented internal functions and
+       data tables that are used by more than one  of  the  exported  external
+       functions,  but  which  are  not  intended for use by external callers.
+       Their names all begin with "_pcre_" or "_pcre16_" or "_pcre32_",  which
+       hopefully  will  not provoke any name clashes. In some environments, it
+       is possible to control which  external  symbols  are  exported  when  a
+       shared  library  is  built, and in these cases the undocumented symbols
+       are not exported.
+
+
+SECURITY CONSIDERATIONS
+
+       If you are using PCRE in a non-UTF application that  permits  users  to
+       supply  arbitrary  patterns  for  compilation, you should be aware of a
+       feature that allows users to turn on UTF support from within a pattern,
+       provided  that  PCRE  was built with UTF support. For example, an 8-bit
+       pattern that begins with "(*UTF8)" or "(*UTF)"  turns  on  UTF-8  mode,
+       which  interprets  patterns and subjects as strings of UTF-8 characters
+       instead of individual 8-bit characters.  This causes both  the  pattern
+       and any data against which it is matched to be checked for UTF-8 valid-
+       ity. If the data string is very long, such a  check  might  use  suffi-
+       ciently  many  resources  as  to cause your application to lose perfor-
+       mance.
+
+       One  way  of  guarding  against  this  possibility  is   to   use   the
+       pcre_fullinfo()  function  to  check the compiled pattern's options for
+       UTF.  Alternatively, from release 8.33, you can set the  PCRE_NEVER_UTF
+       option  at compile time. This causes an compile time error if a pattern
+       contains a UTF-setting sequence.
+
+       If your application is one that supports UTF, be  aware  that  validity
+       checking  can  take time. If the same data string is to be matched many
+       times, you can use the PCRE_NO_UTF[8|16|32]_CHECK option for the second
+       and subsequent matches to save redundant checks.
+
+       Another  way  that  performance can be hit is by running a pattern that
+       has a very large search tree against a string that  will  never  match.
+       Nested  unlimited  repeats in a pattern are a common example. PCRE pro-
+       vides some protection against this: see the PCRE_EXTRA_MATCH_LIMIT fea-
+       ture in the pcreapi page.
+
+
+USER DOCUMENTATION
+
+       The  user  documentation  for PCRE comprises a number of different sec-
+       tions. In the "man" format, each of these is a separate "man page".  In
+       the  HTML  format, each is a separate page, linked from the index page.
+       In the plain text format, the descriptions of the pcregrep and pcretest
+       programs  are  in  files  called pcregrep.txt and pcretest.txt, respec-
+       tively. The remaining sections, except for the pcredemo section  (which
+       is  a  program  listing),  are  concatenated  in  pcre.txt, for ease of
+       searching. The sections are as follows:
+
+         pcre              this document
+         pcre-config       show PCRE installation configuration information
+         pcre16            details of the 16-bit library
+         pcre32            details of the 32-bit library
+         pcreapi           details of PCRE's native C API
+         pcrebuild         building PCRE
+         pcrecallout       details of the callout feature
+         pcrecompat        discussion of Perl compatibility
+         pcrecpp           details of the C++ wrapper for the 8-bit library
+         pcredemo          a demonstration C program that uses PCRE
+         pcregrep          description of the pcregrep command (8-bit only)
+         pcrejit           discussion of the just-in-time optimization support
+         pcrelimits        details of size and other limits
+         pcrematching      discussion of the two matching algorithms
+         pcrepartial       details of the partial matching facility
+         pcrepattern       syntax and semantics of supported
+                             regular expressions
+         pcreperform       discussion of performance issues
+         pcreposix         the POSIX-compatible C API for the 8-bit library
+         pcreprecompile    details of saving and re-using precompiled patterns
+         pcresample        discussion of the pcredemo program
+         pcrestack         discussion of stack usage
+         pcresyntax        quick syntax reference
+         pcretest          description of the pcretest testing command
+         pcreunicode       discussion of Unicode and UTF-8/16/32 support
+
+       In the "man" and HTML formats, there is also a short page  for  each  C
+       library function, listing its arguments and results.
+
+
+AUTHOR
+
+       Philip Hazel
+       University Computing Service
+       Cambridge CB2 3QH, England.
+
+       Putting  an actual email address here seems to have been a spam magnet,
+       so I've taken it away. If you want to email me, use  my  two  initials,
+       followed by the two digits 10, at the domain cam.ac.uk.
+
+
+REVISION
+
+       Last updated: 08 January 2014
+       Copyright (c) 1997-2014 University of Cambridge.
+------------------------------------------------------------------------------
+
+
+PCRE(3)                    Library Functions Manual                    PCRE(3)
+
+
+
+NAME
+       PCRE - Perl-compatible regular expressions
+
+       #include <pcre.h>
+
+
+PCRE 16-BIT API BASIC FUNCTIONS
+
+       pcre16 *pcre16_compile(PCRE_SPTR16 pattern, int options,
+            const char **errptr, int *erroffset,
+            const unsigned char *tableptr);
+
+       pcre16 *pcre16_compile2(PCRE_SPTR16 pattern, int options,
+            int *errorcodeptr,
+            const char **errptr, int *erroffset,
+            const unsigned char *tableptr);
+
+       pcre16_extra *pcre16_study(const pcre16 *code, int options,
+            const char **errptr);
+
+       void pcre16_free_study(pcre16_extra *extra);
+
+       int pcre16_exec(const pcre16 *code, const pcre16_extra *extra,
+            PCRE_SPTR16 subject, int length, int startoffset,
+            int options, int *ovector, int ovecsize);
+
+       int pcre16_dfa_exec(const pcre16 *code, const pcre16_extra *extra,
+            PCRE_SPTR16 subject, int length, int startoffset,
+            int options, int *ovector, int ovecsize,
+            int *workspace, int wscount);
+
+
+PCRE 16-BIT API STRING EXTRACTION FUNCTIONS
+
+       int pcre16_copy_named_substring(const pcre16 *code,
+            PCRE_SPTR16 subject, int *ovector,
+            int stringcount, PCRE_SPTR16 stringname,
+            PCRE_UCHAR16 *buffer, int buffersize);
+
+       int pcre16_copy_substring(PCRE_SPTR16 subject, int *ovector,
+            int stringcount, int stringnumber, PCRE_UCHAR16 *buffer,
+            int buffersize);
+
+       int pcre16_get_named_substring(const pcre16 *code,
+            PCRE_SPTR16 subject, int *ovector,
+            int stringcount, PCRE_SPTR16 stringname,
+            PCRE_SPTR16 *stringptr);
+
+       int pcre16_get_stringnumber(const pcre16 *code,
+            PCRE_SPTR16 name);
+
+       int pcre16_get_stringtable_entries(const pcre16 *code,
+            PCRE_SPTR16 name, PCRE_UCHAR16 **first, PCRE_UCHAR16 **last);
+
+       int pcre16_get_substring(PCRE_SPTR16 subject, int *ovector,
+            int stringcount, int stringnumber,
+            PCRE_SPTR16 *stringptr);
+
+       int pcre16_get_substring_list(PCRE_SPTR16 subject,
+            int *ovector, int stringcount, PCRE_SPTR16 **listptr);
+
+       void pcre16_free_substring(PCRE_SPTR16 stringptr);
+
+       void pcre16_free_substring_list(PCRE_SPTR16 *stringptr);
+
+
+PCRE 16-BIT API AUXILIARY FUNCTIONS
+
+       pcre16_jit_stack *pcre16_jit_stack_alloc(int startsize, int maxsize);
+
+       void pcre16_jit_stack_free(pcre16_jit_stack *stack);
+
+       void pcre16_assign_jit_stack(pcre16_extra *extra,
+            pcre16_jit_callback callback, void *data);
+
+       const unsigned char *pcre16_maketables(void);
+
+       int pcre16_fullinfo(const pcre16 *code, const pcre16_extra *extra,
+            int what, void *where);
+
+       int pcre16_refcount(pcre16 *code, int adjust);
+
+       int pcre16_config(int what, void *where);
+
+       const char *pcre16_version(void);
+
+       int pcre16_pattern_to_host_byte_order(pcre16 *code,
+            pcre16_extra *extra, const unsigned char *tables);
+
+
+PCRE 16-BIT API INDIRECTED FUNCTIONS
+
+       void *(*pcre16_malloc)(size_t);
+
+       void (*pcre16_free)(void *);
+
+       void *(*pcre16_stack_malloc)(size_t);
+
+       void (*pcre16_stack_free)(void *);
+
+       int (*pcre16_callout)(pcre16_callout_block *);
+
+
+PCRE 16-BIT API 16-BIT-ONLY FUNCTION
+
+       int pcre16_utf16_to_host_byte_order(PCRE_UCHAR16 *output,
+            PCRE_SPTR16 input, int length, int *byte_order,
+            int keep_boms);
+
+
+THE PCRE 16-BIT LIBRARY
+
+       Starting  with  release  8.30, it is possible to compile a PCRE library
+       that supports 16-bit character strings, including  UTF-16  strings,  as
+       well  as  or instead of the original 8-bit library. The majority of the
+       work to make  this  possible  was  done  by  Zoltan  Herczeg.  The  two
+       libraries contain identical sets of functions, used in exactly the same
+       way. Only the names of the functions and the data types of their  argu-
+       ments  and results are different. To avoid over-complication and reduce
+       the documentation maintenance load,  most  of  the  PCRE  documentation
+       describes  the  8-bit  library,  with only occasional references to the
+       16-bit library. This page describes what is different when you use  the
+       16-bit library.
+
+       WARNING:  A  single  application can be linked with both libraries, but
+       you must take care when processing any particular pattern to use  func-
+       tions  from  just one library. For example, if you want to study a pat-
+       tern that was compiled with  pcre16_compile(),  you  must  do  so  with
+       pcre16_study(), not pcre_study(), and you must free the study data with
+       pcre16_free_study().
+
+
+THE HEADER FILE
+
+       There is only one header file, pcre.h. It contains prototypes  for  all
+       the functions in all libraries, as well as definitions of flags, struc-
+       tures, error codes, etc.
+
+
+THE LIBRARY NAME
+
+       In Unix-like systems, the 16-bit library is called libpcre16,  and  can
+       normally  be  accesss  by adding -lpcre16 to the command for linking an
+       application that uses PCRE.
+
+
+STRING TYPES
+
+       In the 8-bit library, strings are passed to PCRE library  functions  as
+       vectors  of  bytes  with  the  C  type "char *". In the 16-bit library,
+       strings are passed as vectors of unsigned 16-bit quantities. The  macro
+       PCRE_UCHAR16  specifies  an  appropriate  data type, and PCRE_SPTR16 is
+       defined as "const PCRE_UCHAR16 *". In very  many  environments,  "short
+       int" is a 16-bit data type. When PCRE is built, it defines PCRE_UCHAR16
+       as "unsigned short int", but checks that it really  is  a  16-bit  data
+       type.  If  it is not, the build fails with an error message telling the
+       maintainer to modify the definition appropriately.
+
+
+STRUCTURE TYPES
+
+       The types of the opaque structures that are used  for  compiled  16-bit
+       patterns  and  JIT stacks are pcre16 and pcre16_jit_stack respectively.
+       The  type  of  the  user-accessible  structure  that  is  returned   by
+       pcre16_study()  is  pcre16_extra, and the type of the structure that is
+       used for passing data to a callout  function  is  pcre16_callout_block.
+       These structures contain the same fields, with the same names, as their
+       8-bit counterparts. The only difference is that pointers  to  character
+       strings are 16-bit instead of 8-bit types.
+
+
+16-BIT FUNCTIONS
+
+       For  every function in the 8-bit library there is a corresponding func-
+       tion in the 16-bit library with a name that starts with pcre16_ instead
+       of  pcre_.  The  prototypes are listed above. In addition, there is one
+       extra function, pcre16_utf16_to_host_byte_order(). This  is  a  utility
+       function  that converts a UTF-16 character string to host byte order if
+       necessary. The other 16-bit  functions  expect  the  strings  they  are
+       passed to be in host byte order.
+
+       The input and output arguments of pcre16_utf16_to_host_byte_order() may
+       point to the same address, that is, conversion in place  is  supported.
+       The output buffer must be at least as long as the input.
+
+       The  length  argument  specifies the number of 16-bit data units in the
+       input string; a negative value specifies a zero-terminated string.
+
+       If byte_order is NULL, it is assumed that the string starts off in host
+       byte  order. This may be changed by byte-order marks (BOMs) anywhere in
+       the string (commonly as the first character).
+
+       If byte_order is not NULL, a non-zero value of the integer to which  it
+       points  means  that  the input starts off in host byte order, otherwise
+       the opposite order is assumed. Again, BOMs in  the  string  can  change
+       this. The final byte order is passed back at the end of processing.
+
+       If  keep_boms  is  not  zero,  byte-order  mark characters (0xfeff) are
+       copied into the output string. Otherwise they are discarded.
+
+       The result of the function is the number of 16-bit  units  placed  into
+       the  output  buffer,  including  the  zero terminator if the string was
+       zero-terminated.
+
+
+SUBJECT STRING OFFSETS
+
+       The lengths and starting offsets of subject strings must  be  specified
+       in  16-bit  data units, and the offsets within subject strings that are
+       returned by the matching functions are in also 16-bit units rather than
+       bytes.
+
+
+NAMED SUBPATTERNS
+
+       The  name-to-number translation table that is maintained for named sub-
+       patterns uses 16-bit characters.  The  pcre16_get_stringtable_entries()
+       function returns the length of each entry in the table as the number of
+       16-bit data units.
+
+
+OPTION NAMES
+
+       There   are   two   new   general   option   names,   PCRE_UTF16    and
+       PCRE_NO_UTF16_CHECK,     which     correspond    to    PCRE_UTF8    and
+       PCRE_NO_UTF8_CHECK in the 8-bit library. In  fact,  these  new  options
+       define  the  same bits in the options word. There is a discussion about
+       the validity of UTF-16 strings in the pcreunicode page.
+
+       For the pcre16_config() function there is an  option  PCRE_CONFIG_UTF16
+       that  returns  1  if UTF-16 support is configured, otherwise 0. If this
+       option  is  given  to  pcre_config()  or  pcre32_config(),  or  if  the
+       PCRE_CONFIG_UTF8  or  PCRE_CONFIG_UTF32  option is given to pcre16_con-
+       fig(), the result is the PCRE_ERROR_BADOPTION error.
+
+
+CHARACTER CODES
+
+       In 16-bit mode, when  PCRE_UTF16  is  not  set,  character  values  are
+       treated in the same way as in 8-bit, non UTF-8 mode, except, of course,
+       that they can range from 0 to 0xffff instead of 0  to  0xff.  Character
+       types  for characters less than 0xff can therefore be influenced by the
+       locale in the same way as before.  Characters greater  than  0xff  have
+       only one case, and no "type" (such as letter or digit).
+
+       In  UTF-16  mode,  the  character  code  is  Unicode, in the range 0 to
+       0x10ffff, with the exception of values in the range  0xd800  to  0xdfff
+       because  those  are "surrogate" values that are used in pairs to encode
+       values greater than 0xffff.
+
+       A UTF-16 string can indicate its endianness by special code knows as  a
+       byte-order mark (BOM). The PCRE functions do not handle this, expecting
+       strings  to  be  in  host  byte  order.  A  utility   function   called
+       pcre16_utf16_to_host_byte_order()  is  provided  to help with this (see
+       above).
+
+
+ERROR NAMES
+
+       The errors PCRE_ERROR_BADUTF16_OFFSET and PCRE_ERROR_SHORTUTF16  corre-
+       spond  to  their  8-bit  counterparts.  The error PCRE_ERROR_BADMODE is
+       given when a compiled pattern is passed to a  function  that  processes
+       patterns  in  the  other  mode, for example, if a pattern compiled with
+       pcre_compile() is passed to pcre16_exec().
+
+       There are new error codes whose names  begin  with  PCRE_UTF16_ERR  for
+       invalid  UTF-16  strings,  corresponding to the PCRE_UTF8_ERR codes for
+       UTF-8 strings that are described in the section entitled "Reason  codes
+       for  invalid UTF-8 strings" in the main pcreapi page. The UTF-16 errors
+       are:
+
+         PCRE_UTF16_ERR1  Missing low surrogate at end of string
+         PCRE_UTF16_ERR2  Invalid low surrogate follows high surrogate
+         PCRE_UTF16_ERR3  Isolated low surrogate
+         PCRE_UTF16_ERR4  Non-character
+
+
+ERROR TEXTS
+
+       If there is an error while compiling a pattern, the error text that  is
+       passed  back by pcre16_compile() or pcre16_compile2() is still an 8-bit
+       character string, zero-terminated.
+
+
+CALLOUTS
+
+       The subject and mark fields in the callout block that is  passed  to  a
+       callout function point to 16-bit vectors.
+
+
+TESTING
+
+       The  pcretest  program continues to operate with 8-bit input and output
+       files, but it can be used for testing the 16-bit library. If it is  run
+       with the command line option -16, patterns and subject strings are con-
+       verted from 8-bit to 16-bit before being passed to PCRE, and the 16-bit
+       library  functions  are used instead of the 8-bit ones. Returned 16-bit
+       strings are converted to 8-bit for output. If both the  8-bit  and  the
+       32-bit libraries were not compiled, pcretest defaults to 16-bit and the
+       -16 option is ignored.
+
+       When PCRE is being built, the RunTest script that is  called  by  "make
+       check"  uses  the  pcretest  -C  option to discover which of the 8-bit,
+       16-bit and 32-bit libraries has been built, and runs the  tests  appro-
+       priately.
+
+
+NOT SUPPORTED IN 16-BIT MODE
+
+       Not all the features of the 8-bit library are available with the 16-bit
+       library. The C++ and POSIX wrapper functions  support  only  the  8-bit
+       library, and the pcregrep program is at present 8-bit only.
+
+
+AUTHOR
+
+       Philip Hazel
+       University Computing Service
+       Cambridge CB2 3QH, England.
+
+
+REVISION
+
+       Last updated: 12 May 2013
+       Copyright (c) 1997-2013 University of Cambridge.
+------------------------------------------------------------------------------
+
+
+PCRE(3)                    Library Functions Manual                    PCRE(3)
+
+
+
+NAME
+       PCRE - Perl-compatible regular expressions
+
+       #include <pcre.h>
+
+
+PCRE 32-BIT API BASIC FUNCTIONS
+
+       pcre32 *pcre32_compile(PCRE_SPTR32 pattern, int options,
+            const char **errptr, int *erroffset,
+            const unsigned char *tableptr);
+
+       pcre32 *pcre32_compile2(PCRE_SPTR32 pattern, int options,
+            int *errorcodeptr,
+            const unsigned char *tableptr);
+
+       pcre32_extra *pcre32_study(const pcre32 *code, int options,
+            const char **errptr);
+
+       void pcre32_free_study(pcre32_extra *extra);
+
+       int pcre32_exec(const pcre32 *code, const pcre32_extra *extra,
+            PCRE_SPTR32 subject, int length, int startoffset,
+            int options, int *ovector, int ovecsize);
+
+       int pcre32_dfa_exec(const pcre32 *code, const pcre32_extra *extra,
+            PCRE_SPTR32 subject, int length, int startoffset,
+            int options, int *ovector, int ovecsize,
+            int *workspace, int wscount);
+
+
+PCRE 32-BIT API STRING EXTRACTION FUNCTIONS
+
+       int pcre32_copy_named_substring(const pcre32 *code,
+            PCRE_SPTR32 subject, int *ovector,
+            int stringcount, PCRE_SPTR32 stringname,
+            PCRE_UCHAR32 *buffer, int buffersize);
+
+       int pcre32_copy_substring(PCRE_SPTR32 subject, int *ovector,
+            int stringcount, int stringnumber, PCRE_UCHAR32 *buffer,
+            int buffersize);
+
+       int pcre32_get_named_substring(const pcre32 *code,
+            PCRE_SPTR32 subject, int *ovector,
+            int stringcount, PCRE_SPTR32 stringname,
+            PCRE_SPTR32 *stringptr);
+
+       int pcre32_get_stringnumber(const pcre32 *code,
+            PCRE_SPTR32 name);
+
+       int pcre32_get_stringtable_entries(const pcre32 *code,
+            PCRE_SPTR32 name, PCRE_UCHAR32 **first, PCRE_UCHAR32 **last);
+
+       int pcre32_get_substring(PCRE_SPTR32 subject, int *ovector,
+            int stringcount, int stringnumber,
+            PCRE_SPTR32 *stringptr);
+
+       int pcre32_get_substring_list(PCRE_SPTR32 subject,
+            int *ovector, int stringcount, PCRE_SPTR32 **listptr);
+
+       void pcre32_free_substring(PCRE_SPTR32 stringptr);
+
+       void pcre32_free_substring_list(PCRE_SPTR32 *stringptr);
+
+
+PCRE 32-BIT API AUXILIARY FUNCTIONS
+
+       pcre32_jit_stack *pcre32_jit_stack_alloc(int startsize, int maxsize);
+
+       void pcre32_jit_stack_free(pcre32_jit_stack *stack);
+
+       void pcre32_assign_jit_stack(pcre32_extra *extra,
+            pcre32_jit_callback callback, void *data);
+
+       const unsigned char *pcre32_maketables(void);
+
+       int pcre32_fullinfo(const pcre32 *code, const pcre32_extra *extra,
+            int what, void *where);
+
+       int pcre32_refcount(pcre32 *code, int adjust);
+
+       int pcre32_config(int what, void *where);
+
+       const char *pcre32_version(void);
+
+       int pcre32_pattern_to_host_byte_order(pcre32 *code,
+            pcre32_extra *extra, const unsigned char *tables);
+
+
+PCRE 32-BIT API INDIRECTED FUNCTIONS
+
+       void *(*pcre32_malloc)(size_t);
+
+       void (*pcre32_free)(void *);
+
+       void *(*pcre32_stack_malloc)(size_t);
+
+       void (*pcre32_stack_free)(void *);
+
+       int (*pcre32_callout)(pcre32_callout_block *);
+
+
+PCRE 32-BIT API 32-BIT-ONLY FUNCTION
+
+       int pcre32_utf32_to_host_byte_order(PCRE_UCHAR32 *output,
+            PCRE_SPTR32 input, int length, int *byte_order,
+            int keep_boms);
+
+
+THE PCRE 32-BIT LIBRARY
+
+       Starting  with  release  8.32, it is possible to compile a PCRE library
+       that supports 32-bit character strings, including  UTF-32  strings,  as
+       well as or instead of the original 8-bit library. This work was done by
+       Christian Persch, based on the work done  by  Zoltan  Herczeg  for  the
+       16-bit  library.  All  three  libraries contain identical sets of func-
+       tions, used in exactly the same way.  Only the names of  the  functions
+       and  the  data  types  of their arguments and results are different. To
+       avoid over-complication and reduce the documentation maintenance  load,
+       most  of  the PCRE documentation describes the 8-bit library, with only
+       occasional references to the 16-bit and  32-bit  libraries.  This  page
+       describes what is different when you use the 32-bit library.
+
+       WARNING:  A  single  application  can  be linked with all or any of the
+       three libraries, but you must take care when processing any  particular
+       pattern  to  use  functions  from just one library. For example, if you
+       want to study a pattern that was compiled  with  pcre32_compile(),  you
+       must do so with pcre32_study(), not pcre_study(), and you must free the
+       study data with pcre32_free_study().
+
+
+THE HEADER FILE
+
+       There is only one header file, pcre.h. It contains prototypes  for  all
+       the functions in all libraries, as well as definitions of flags, struc-
+       tures, error codes, etc.
+
+
+THE LIBRARY NAME
+
+       In Unix-like systems, the 32-bit library is called libpcre32,  and  can
+       normally  be  accesss  by adding -lpcre32 to the command for linking an
+       application that uses PCRE.
+
+
+STRING TYPES
+
+       In the 8-bit library, strings are passed to PCRE library  functions  as
+       vectors  of  bytes  with  the  C  type "char *". In the 32-bit library,
+       strings are passed as vectors of unsigned 32-bit quantities. The  macro
+       PCRE_UCHAR32  specifies  an  appropriate  data type, and PCRE_SPTR32 is
+       defined as "const PCRE_UCHAR32 *". In very many environments, "unsigned
+       int" is a 32-bit data type. When PCRE is built, it defines PCRE_UCHAR32
+       as "unsigned int", but checks that it really is a 32-bit data type.  If
+       it is not, the build fails with an error message telling the maintainer
+       to modify the definition appropriately.
+
+
+STRUCTURE TYPES
+
+       The types of the opaque structures that are used  for  compiled  32-bit
+       patterns  and  JIT stacks are pcre32 and pcre32_jit_stack respectively.
+       The  type  of  the  user-accessible  structure  that  is  returned   by
+       pcre32_study()  is  pcre32_extra, and the type of the structure that is
+       used for passing data to a callout  function  is  pcre32_callout_block.
+       These structures contain the same fields, with the same names, as their
+       8-bit counterparts. The only difference is that pointers  to  character
+       strings are 32-bit instead of 8-bit types.
+
+
+32-BIT FUNCTIONS
+
+       For  every function in the 8-bit library there is a corresponding func-
+       tion in the 32-bit library with a name that starts with pcre32_ instead
+       of  pcre_.  The  prototypes are listed above. In addition, there is one
+       extra function, pcre32_utf32_to_host_byte_order(). This  is  a  utility
+       function  that converts a UTF-32 character string to host byte order if
+       necessary. The other 32-bit  functions  expect  the  strings  they  are
+       passed to be in host byte order.
+
+       The input and output arguments of pcre32_utf32_to_host_byte_order() may
+       point to the same address, that is, conversion in place  is  supported.
+       The output buffer must be at least as long as the input.
+
+       The  length  argument  specifies the number of 32-bit data units in the
+       input string; a negative value specifies a zero-terminated string.
+
+       If byte_order is NULL, it is assumed that the string starts off in host
+       byte  order. This may be changed by byte-order marks (BOMs) anywhere in
+       the string (commonly as the first character).
+
+       If byte_order is not NULL, a non-zero value of the integer to which  it
+       points  means  that  the input starts off in host byte order, otherwise
+       the opposite order is assumed. Again, BOMs in  the  string  can  change
+       this. The final byte order is passed back at the end of processing.
+
+       If  keep_boms  is  not  zero,  byte-order  mark characters (0xfeff) are
+       copied into the output string. Otherwise they are discarded.
+
+       The result of the function is the number of 32-bit  units  placed  into
+       the  output  buffer,  including  the  zero terminator if the string was
+       zero-terminated.
+
+
+SUBJECT STRING OFFSETS
+
+       The lengths and starting offsets of subject strings must  be  specified
+       in  32-bit  data units, and the offsets within subject strings that are
+       returned by the matching functions are in also 32-bit units rather than
+       bytes.
+
+
+NAMED SUBPATTERNS
+
+       The  name-to-number translation table that is maintained for named sub-
+       patterns uses 32-bit characters.  The  pcre32_get_stringtable_entries()
+       function returns the length of each entry in the table as the number of
+       32-bit data units.
+
+
+OPTION NAMES
+
+       There   are   two   new   general   option   names,   PCRE_UTF32    and
+       PCRE_NO_UTF32_CHECK,     which     correspond    to    PCRE_UTF8    and
+       PCRE_NO_UTF8_CHECK in the 8-bit library. In  fact,  these  new  options
+       define  the  same bits in the options word. There is a discussion about
+       the validity of UTF-32 strings in the pcreunicode page.
+
+       For the pcre32_config() function there is an  option  PCRE_CONFIG_UTF32
+       that  returns  1  if UTF-32 support is configured, otherwise 0. If this
+       option  is  given  to  pcre_config()  or  pcre16_config(),  or  if  the
+       PCRE_CONFIG_UTF8  or  PCRE_CONFIG_UTF16  option is given to pcre32_con-
+       fig(), the result is the PCRE_ERROR_BADOPTION error.
+
+
+CHARACTER CODES
+
+       In 32-bit mode, when  PCRE_UTF32  is  not  set,  character  values  are
+       treated in the same way as in 8-bit, non UTF-8 mode, except, of course,
+       that they can range from 0 to 0x7fffffff instead of 0 to 0xff.  Charac-
+       ter  types for characters less than 0xff can therefore be influenced by
+       the locale in the same way as before.   Characters  greater  than  0xff
+       have only one case, and no "type" (such as letter or digit).
+
+       In  UTF-32  mode,  the  character  code  is  Unicode, in the range 0 to
+       0x10ffff, with the exception of values in the range  0xd800  to  0xdfff
+       because those are "surrogate" values that are ill-formed in UTF-32.
+
+       A  UTF-32 string can indicate its endianness by special code knows as a
+       byte-order mark (BOM). The PCRE functions do not handle this, expecting
+       strings   to   be  in  host  byte  order.  A  utility  function  called
+       pcre32_utf32_to_host_byte_order() is provided to help  with  this  (see
+       above).
+
+
+ERROR NAMES
+
+       The  error  PCRE_ERROR_BADUTF32  corresponds  to its 8-bit counterpart.
+       The error PCRE_ERROR_BADMODE is given when a compiled pattern is passed
+       to  a  function that processes patterns in the other mode, for example,
+       if a pattern compiled with pcre_compile() is passed to pcre32_exec().
+
+       There are new error codes whose names  begin  with  PCRE_UTF32_ERR  for
+       invalid  UTF-32  strings,  corresponding to the PCRE_UTF8_ERR codes for
+       UTF-8 strings that are described in the section entitled "Reason  codes
+       for  invalid UTF-8 strings" in the main pcreapi page. The UTF-32 errors
+       are:
+
+         PCRE_UTF32_ERR1  Surrogate character (range from 0xd800 to 0xdfff)
+         PCRE_UTF32_ERR2  Non-character
+         PCRE_UTF32_ERR3  Character > 0x10ffff
+
+
+ERROR TEXTS
+
+       If there is an error while compiling a pattern, the error text that  is
+       passed  back by pcre32_compile() or pcre32_compile2() is still an 8-bit
+       character string, zero-terminated.
+
+
+CALLOUTS
+
+       The subject and mark fields in the callout block that is  passed  to  a
+       callout function point to 32-bit vectors.
+
+
+TESTING
+
+       The  pcretest  program continues to operate with 8-bit input and output
+       files, but it can be used for testing the 32-bit library. If it is  run
+       with the command line option -32, patterns and subject strings are con-
+       verted from 8-bit to 32-bit before being passed to PCRE, and the 32-bit
+       library  functions  are used instead of the 8-bit ones. Returned 32-bit
+       strings are converted to 8-bit for output. If both the  8-bit  and  the
+       16-bit libraries were not compiled, pcretest defaults to 32-bit and the
+       -32 option is ignored.
+
+       When PCRE is being built, the RunTest script that is  called  by  "make
+       check"  uses  the  pcretest  -C  option to discover which of the 8-bit,
+       16-bit and 32-bit libraries has been built, and runs the  tests  appro-
+       priately.
+
+
+NOT SUPPORTED IN 32-BIT MODE
+
+       Not all the features of the 8-bit library are available with the 32-bit
+       library. The C++ and POSIX wrapper functions  support  only  the  8-bit
+       library, and the pcregrep program is at present 8-bit only.
+
+
+AUTHOR
+
+       Philip Hazel
+       University Computing Service
+       Cambridge CB2 3QH, England.
+
+
+REVISION
+
+       Last updated: 12 May 2013
+       Copyright (c) 1997-2013 University of Cambridge.
+------------------------------------------------------------------------------
+
+
+PCREBUILD(3)               Library Functions Manual               PCREBUILD(3)
+
+
+
+NAME
+       PCRE - Perl-compatible regular expressions
+
+BUILDING PCRE
+
+       PCRE  is  distributed with a configure script that can be used to build
+       the library in Unix-like environments using the applications  known  as
+       Autotools.   Also  in  the  distribution  are files to support building
+       using CMake instead of configure. The text file README contains general
+       information  about  building  with Autotools (some of which is repeated
+       below), and also has some comments about building on various  operating
+       systems.  There  is  a lot more information about building PCRE without
+       using Autotools (including information about using CMake  and  building
+       "by  hand")  in  the  text file called NON-AUTOTOOLS-BUILD.  You should
+       consult this file as well as the README file if you are building  in  a
+       non-Unix-like environment.
+
+
+PCRE BUILD-TIME OPTIONS
+
+       The  rest of this document describes the optional features of PCRE that
+       can be selected when the library is compiled. It  assumes  use  of  the
+       configure  script,  where  the  optional features are selected or dese-
+       lected by providing options to configure before running the  make  com-
+       mand.  However,  the same options can be selected in both Unix-like and
+       non-Unix-like environments using the GUI facility of cmake-gui  if  you
+       are using CMake instead of configure to build PCRE.
+
+       If  you  are not using Autotools or CMake, option selection can be done
+       by editing the config.h file, or by passing parameter settings  to  the
+       compiler, as described in NON-AUTOTOOLS-BUILD.
+
+       The complete list of options for configure (which includes the standard
+       ones such as the  selection  of  the  installation  directory)  can  be
+       obtained by running
+
+         ./configure --help
+
+       The  following  sections  include  descriptions  of options whose names
+       begin with --enable or --disable. These settings specify changes to the
+       defaults  for  the configure command. Because of the way that configure
+       works, --enable and --disable always come in pairs, so  the  complemen-
+       tary  option always exists as well, but as it specifies the default, it
+       is not described.
+
+
+BUILDING 8-BIT, 16-BIT AND 32-BIT LIBRARIES
+
+       By default, a library called libpcre  is  built,  containing  functions
+       that  take  string  arguments  contained in vectors of bytes, either as
+       single-byte characters, or interpreted as UTF-8 strings. You  can  also
+       build  a  separate library, called libpcre16, in which strings are con-
+       tained in vectors of 16-bit data units and interpreted either  as  sin-
+       gle-unit characters or UTF-16 strings, by adding
+
+         --enable-pcre16
+
+       to  the  configure  command.  You  can  also build yet another separate
+       library, called libpcre32, in which strings are contained in vectors of
+       32-bit  data  units and interpreted either as single-unit characters or
+       UTF-32 strings, by adding
+
+         --enable-pcre32
+
+       to the configure command. If you do not want the 8-bit library, add
+
+         --disable-pcre8
+
+       as well. At least one of the three libraries must be built.  Note  that
+       the  C++  and  POSIX  wrappers are for the 8-bit library only, and that
+       pcregrep is an 8-bit program. None of these are  built  if  you  select
+       only the 16-bit or 32-bit libraries.
+
+
+BUILDING SHARED AND STATIC LIBRARIES
+
+       The  Autotools  PCRE building process uses libtool to build both shared
+       and static libraries by default. You  can  suppress  one  of  these  by
+       adding one of
+
+         --disable-shared
+         --disable-static
+
+       to the configure command, as required.
+
+
+C++ SUPPORT
+
+       By  default,  if the 8-bit library is being built, the configure script
+       will search for a C++ compiler and C++ header files. If it finds  them,
+       it  automatically  builds  the C++ wrapper library (which supports only
+       8-bit strings). You can disable this by adding
+
+         --disable-cpp
+
+       to the configure command.
+
+
+UTF-8, UTF-16 AND UTF-32 SUPPORT
+
+       To build PCRE with support for UTF Unicode character strings, add
+
+         --enable-utf
+
+       to the configure command. This setting applies to all three  libraries,
+       adding  support  for  UTF-8 to the 8-bit library, support for UTF-16 to
+       the 16-bit library, and  support  for  UTF-32  to  the  to  the  32-bit
+       library.  There  are no separate options for enabling UTF-8, UTF-16 and
+       UTF-32 independently because that would allow ridiculous settings  such
+       as  requesting UTF-16 support while building only the 8-bit library. It
+       is not possible to build one library with UTF support and another with-
+       out  in the same configuration. (For backwards compatibility, --enable-
+       utf8 is a synonym of --enable-utf.)
+
+       Of itself, this setting does not make  PCRE  treat  strings  as  UTF-8,
+       UTF-16  or UTF-32. As well as compiling PCRE with this option, you also
+       have have to set the PCRE_UTF8, PCRE_UTF16  or  PCRE_UTF32  option  (as
+       appropriate) when you call one of the pattern compiling functions.
+
+       If  you  set --enable-utf when compiling in an EBCDIC environment, PCRE
+       expects its input to be either ASCII or UTF-8 (depending  on  the  run-
+       time option). It is not possible to support both EBCDIC and UTF-8 codes
+       in the same version of  the  library.  Consequently,  --enable-utf  and
+       --enable-ebcdic are mutually exclusive.
+
+
+UNICODE CHARACTER PROPERTY SUPPORT
+
+       UTF  support allows the libraries to process character codepoints up to
+       0x10ffff in the strings that they handle. On its own, however, it  does
+       not provide any facilities for accessing the properties of such charac-
+       ters. If you want to be able to use the pattern escapes \P, \p, and \X,
+       which refer to Unicode character properties, you must add
+
+         --enable-unicode-properties
+
+       to  the  configure  command. This implies UTF support, even if you have
+       not explicitly requested it.
+
+       Including Unicode property support adds around 30K  of  tables  to  the
+       PCRE  library.  Only  the general category properties such as Lu and Nd
+       are supported. Details are given in the pcrepattern documentation.
+
+
+JUST-IN-TIME COMPILER SUPPORT
+
+       Just-in-time compiler support is included in the build by specifying
+
+         --enable-jit
+
+       This support is available only for certain hardware  architectures.  If
+       this  option  is  set  for  an unsupported architecture, a compile time
+       error occurs.  See the pcrejit documentation for a  discussion  of  JIT
+       usage. When JIT support is enabled, pcregrep automatically makes use of
+       it, unless you add
+
+         --disable-pcregrep-jit
+
+       to the "configure" command.
+
+
+CODE VALUE OF NEWLINE
+
+       By default, PCRE interprets the linefeed (LF) character  as  indicating
+       the  end  of  a line. This is the normal newline character on Unix-like
+       systems. You can compile PCRE to use carriage return (CR)  instead,  by
+       adding
+
+         --enable-newline-is-cr
+
+       to  the  configure  command.  There  is  also  a --enable-newline-is-lf
+       option, which explicitly specifies linefeed as the newline character.
+
+       Alternatively, you can specify that line endings are to be indicated by
+       the two character sequence CRLF. If you want this, add
+
+         --enable-newline-is-crlf
+
+       to the configure command. There is a fourth option, specified by
+
+         --enable-newline-is-anycrlf
+
+       which  causes  PCRE  to recognize any of the three sequences CR, LF, or
+       CRLF as indicating a line ending. Finally, a fifth option, specified by
+
+         --enable-newline-is-any
+
+       causes PCRE to recognize any Unicode newline sequence.
+
+       Whatever line ending convention is selected when PCRE is built  can  be
+       overridden  when  the library functions are called. At build time it is
+       conventional to use the standard for your operating system.
+
+
+WHAT \R MATCHES
+
+       By default, the sequence \R in a pattern matches  any  Unicode  newline
+       sequence,  whatever  has  been selected as the line ending sequence. If
+       you specify
+
+         --enable-bsr-anycrlf
+
+       the default is changed so that \R matches only CR, LF, or  CRLF.  What-
+       ever  is selected when PCRE is built can be overridden when the library
+       functions are called.
+
+
+POSIX MALLOC USAGE
+
+       When the 8-bit library is called through the POSIX interface  (see  the
+       pcreposix  documentation),  additional  working storage is required for
+       holding the pointers to capturing  substrings,  because  PCRE  requires
+       three integers per substring, whereas the POSIX interface provides only
+       two. If the number of expected substrings is small, the  wrapper  func-
+       tion  uses  space  on the stack, because this is faster than using mal-
+       loc() for each call. The default threshold above which the stack is  no
+       longer used is 10; it can be changed by adding a setting such as
+
+         --with-posix-malloc-threshold=20
+
+       to the configure command.
+
+
+HANDLING VERY LARGE PATTERNS
+
+       Within  a  compiled  pattern,  offset values are used to point from one
+       part to another (for example, from an opening parenthesis to an  alter-
+       nation  metacharacter).  By default, in the 8-bit and 16-bit libraries,
+       two-byte values are used for these offsets, leading to a  maximum  size
+       for  a compiled pattern of around 64K. This is sufficient to handle all
+       but the most gigantic patterns.  Nevertheless, some people do  want  to
+       process  truly  enormous patterns, so it is possible to compile PCRE to
+       use three-byte or four-byte offsets by adding a setting such as
+
+         --with-link-size=3
+
+       to the configure command. The value given must be 2, 3, or 4.  For  the
+       16-bit  library,  a  value of 3 is rounded up to 4. In these libraries,
+       using longer offsets slows down the operation of PCRE because it has to
+       load  additional  data  when  handling them. For the 32-bit library the
+       value is always 4 and cannot be overridden; the value  of  --with-link-
+       size is ignored.
+
+
+AVOIDING EXCESSIVE STACK USAGE
+
+       When matching with the pcre_exec() function, PCRE implements backtrack-
+       ing by making recursive calls to an internal function  called  match().
+       In  environments  where  the size of the stack is limited, this can se-
+       verely limit PCRE's operation. (The Unix environment does  not  usually
+       suffer from this problem, but it may sometimes be necessary to increase
+       the maximum stack size.  There is a discussion in the  pcrestack  docu-
+       mentation.)  An alternative approach to recursion that uses memory from
+       the heap to remember data, instead of using recursive  function  calls,
+       has  been  implemented to work round the problem of limited stack size.
+       If you want to build a version of PCRE that works this way, add
+
+         --disable-stack-for-recursion
+
+       to the configure command. With this configuration, PCRE  will  use  the
+       pcre_stack_malloc  and pcre_stack_free variables to call memory manage-
+       ment functions. By default these point to malloc() and free(), but  you
+       can replace the pointers so that your own functions are used instead.
+
+       Separate  functions  are  provided  rather  than  using pcre_malloc and
+       pcre_free because the  usage  is  very  predictable:  the  block  sizes
+       requested  are  always  the  same,  and  the blocks are always freed in
+       reverse order. A calling program might be able to  implement  optimized
+       functions  that  perform  better  than  malloc()  and free(). PCRE runs
+       noticeably more slowly when built in this way. This option affects only
+       the pcre_exec() function; it is not relevant for pcre_dfa_exec().
+
+
+LIMITING PCRE RESOURCE USAGE
+
+       Internally,  PCRE has a function called match(), which it calls repeat-
+       edly  (sometimes  recursively)  when  matching  a  pattern   with   the
+       pcre_exec()  function.  By controlling the maximum number of times this
+       function may be called during a single matching operation, a limit  can
+       be  placed  on  the resources used by a single call to pcre_exec(). The
+       limit can be changed at run time, as described in the pcreapi  documen-
+       tation.  The default is 10 million, but this can be changed by adding a
+       setting such as
+
+         --with-match-limit=500000
+
+       to  the  configure  command.  This  setting  has  no  effect   on   the
+       pcre_dfa_exec() matching function.
+
+       In  some  environments  it is desirable to limit the depth of recursive
+       calls of match() more strictly than the total number of calls, in order
+       to  restrict  the maximum amount of stack (or heap, if --disable-stack-
+       for-recursion is specified) that is used. A second limit controls this;
+       it  defaults  to  the  value  that is set for --with-match-limit, which
+       imposes no additional constraints. However, you can set a  lower  limit
+       by adding, for example,
+
+         --with-match-limit-recursion=10000
+
+       to  the  configure  command.  This  value can also be overridden at run
+       time.
+
+
+CREATING CHARACTER TABLES AT BUILD TIME
+
+       PCRE uses fixed tables for processing characters whose code values  are
+       less  than 256. By default, PCRE is built with a set of tables that are
+       distributed in the file pcre_chartables.c.dist. These  tables  are  for
+       ASCII codes only. If you add
+
+         --enable-rebuild-chartables
+
+       to  the  configure  command, the distributed tables are no longer used.
+       Instead, a program called dftables is compiled and  run.  This  outputs
+       the source for new set of tables, created in the default locale of your
+       C run-time system. (This method of replacing the tables does  not  work
+       if  you are cross compiling, because dftables is run on the local host.
+       If you need to create alternative tables when cross compiling, you will
+       have to do so "by hand".)
+
+
+USING EBCDIC CODE
+
+       PCRE  assumes  by  default that it will run in an environment where the
+       character code is ASCII (or Unicode, which is  a  superset  of  ASCII).
+       This  is  the  case for most computer operating systems. PCRE can, how-
+       ever, be compiled to run in an EBCDIC environment by adding
+
+         --enable-ebcdic
+
+       to the configure command. This setting implies --enable-rebuild-charta-
+       bles.  You  should  only  use  it if you know that you are in an EBCDIC
+       environment (for example,  an  IBM  mainframe  operating  system).  The
+       --enable-ebcdic option is incompatible with --enable-utf.
+
+       The EBCDIC character that corresponds to an ASCII LF is assumed to have
+       the value 0x15 by default. However, in some EBCDIC  environments,  0x25
+       is used. In such an environment you should use
+
+         --enable-ebcdic-nl25
+
+       as well as, or instead of, --enable-ebcdic. The EBCDIC character for CR
+       has the same value as in ASCII, namely, 0x0d.  Whichever  of  0x15  and
+       0x25 is not chosen as LF is made to correspond to the Unicode NEL char-
+       acter (which, in Unicode, is 0x85).
+
+       The options that select newline behaviour, such as --enable-newline-is-
+       cr, and equivalent run-time options, refer to these character values in
+       an EBCDIC environment.
+
+
+PCREGREP OPTIONS FOR COMPRESSED FILE SUPPORT
+
+       By default, pcregrep reads all files as plain text. You can build it so
+       that it recognizes files whose names end in .gz or .bz2, and reads them
+       with libz or libbz2, respectively, by adding one or both of
+
+         --enable-pcregrep-libz
+         --enable-pcregrep-libbz2
+
+       to the configure command. These options naturally require that the rel-
+       evant  libraries  are installed on your system. Configuration will fail
+       if they are not.
+
+
+PCREGREP BUFFER SIZE
+
+       pcregrep uses an internal buffer to hold a "window" on the file  it  is
+       scanning, in order to be able to output "before" and "after" lines when
+       it finds a match. The size of the buffer is controlled by  a  parameter
+       whose default value is 20K. The buffer itself is three times this size,
+       but because of the way it is used for holding "before" lines, the long-
+       est  line  that  is guaranteed to be processable is the parameter size.
+       You can change the default parameter value by adding, for example,
+
+         --with-pcregrep-bufsize=50K
+
+       to the configure command. The caller of pcregrep can, however, override
+       this value by specifying a run-time option.
+
+
+PCRETEST OPTION FOR LIBREADLINE SUPPORT
+
+       If you add
+
+         --enable-pcretest-libreadline
+
+       to  the  configure  command,  pcretest  is  linked with the libreadline
+       library, and when its input is from a terminal, it reads it  using  the
+       readline() function. This provides line-editing and history facilities.
+       Note that libreadline is GPL-licensed, so if you distribute a binary of
+       pcretest linked in this way, there may be licensing issues.
+
+       Setting  this  option  causes  the -lreadline option to be added to the
+       pcretest build. In many operating environments with  a  sytem-installed
+       libreadline this is sufficient. However, in some environments (e.g.  if
+       an unmodified distribution version of readline is in use),  some  extra
+       configuration  may  be necessary. The INSTALL file for libreadline says
+       this:
+
+         "Readline uses the termcap functions, but does not link with the
+         termcap or curses library itself, allowing applications which link
+         with readline the to choose an appropriate library."
+
+       If your environment has not been set up so that an appropriate  library
+       is automatically included, you may need to add something like
+
+         LIBS="-ncurses"
+
+       immediately before the configure command.
+
+
+DEBUGGING WITH VALGRIND SUPPORT
+
+       By adding the
+
+         --enable-valgrind
+
+       option  to to the configure command, PCRE will use valgrind annotations
+       to mark certain memory regions as  unaddressable.  This  allows  it  to
+       detect invalid memory accesses, and is mostly useful for debugging PCRE
+       itself.
+
+
+CODE COVERAGE REPORTING
+
+       If your C compiler is gcc, you can build a version  of  PCRE  that  can
+       generate a code coverage report for its test suite. To enable this, you
+       must install lcov version 1.6 or above. Then specify
+
+         --enable-coverage
+
+       to the configure command and build PCRE in the usual way.
+
+       Note that using ccache (a caching C compiler) is incompatible with code
+       coverage  reporting. If you have configured ccache to run automatically
+       on your system, you must set the environment variable
+
+         CCACHE_DISABLE=1
+
+       before running make to build PCRE, so that ccache is not used.
+
+       When --enable-coverage is used,  the  following  addition  targets  are
+       added to the Makefile:
+
+         make coverage
+
+       This  creates  a  fresh  coverage report for the PCRE test suite. It is
+       equivalent to running "make coverage-reset", "make  coverage-baseline",
+       "make check", and then "make coverage-report".
+
+         make coverage-reset
+
+       This zeroes the coverage counters, but does nothing else.
+
+         make coverage-baseline
+
+       This captures baseline coverage information.
+
+         make coverage-report
+
+       This creates the coverage report.
+
+         make coverage-clean-report
+
+       This  removes the generated coverage report without cleaning the cover-
+       age data itself.
+
+         make coverage-clean-data
+
+       This removes the captured coverage data without removing  the  coverage
+       files created at compile time (*.gcno).
+
+         make coverage-clean
+
+       This  cleans all coverage data including the generated coverage report.
+       For more information about code coverage, see the gcov and  lcov  docu-
+       mentation.
+
+
+SEE ALSO
+
+       pcreapi(3), pcre16, pcre32, pcre_config(3).
+
+
+AUTHOR
+
+       Philip Hazel
+       University Computing Service
+       Cambridge CB2 3QH, England.
+
+
+REVISION
+
+       Last updated: 12 May 2013
+       Copyright (c) 1997-2013 University of Cambridge.
+------------------------------------------------------------------------------
+
+
+PCREMATCHING(3)            Library Functions Manual            PCREMATCHING(3)
+
+
+
+NAME
+       PCRE - Perl-compatible regular expressions
+
+PCRE MATCHING ALGORITHMS
+
+       This document describes the two different algorithms that are available
+       in PCRE for matching a compiled regular expression against a given sub-
+       ject  string.  The  "standard"  algorithm  is  the  one provided by the
+       pcre_exec(), pcre16_exec() and pcre32_exec() functions. These  work  in
+       the  same as as Perl's matching function, and provide a Perl-compatible
+       matching  operation.   The  just-in-time  (JIT)  optimization  that  is
+       described  in  the pcrejit documentation is compatible with these func-
+       tions.
+
+       An  alternative  algorithm  is   provided   by   the   pcre_dfa_exec(),
+       pcre16_dfa_exec()  and  pcre32_dfa_exec()  functions; they operate in a
+       different way, and are not Perl-compatible. This alternative has advan-
+       tages and disadvantages compared with the standard algorithm, and these
+       are described below.
+
+       When there is only one possible way in which a given subject string can
+       match  a pattern, the two algorithms give the same answer. A difference
+       arises, however, when there are multiple possibilities. For example, if
+       the pattern
+
+         ^<.*>
+
+       is matched against the string
+
+         <something> <something else> <something further>
+
+       there are three possible answers. The standard algorithm finds only one
+       of them, whereas the alternative algorithm finds all three.
+
+
+REGULAR EXPRESSIONS AS TREES
+
+       The set of strings that are matched by a regular expression can be rep-
+       resented  as  a  tree structure. An unlimited repetition in the pattern
+       makes the tree of infinite size, but it is still a tree.  Matching  the
+       pattern  to a given subject string (from a given starting point) can be
+       thought of as a search of the tree.  There are two  ways  to  search  a
+       tree:  depth-first  and  breadth-first, and these correspond to the two
+       matching algorithms provided by PCRE.
+
+
+THE STANDARD MATCHING ALGORITHM
+
+       In the terminology of Jeffrey Friedl's book "Mastering Regular  Expres-
+       sions",  the  standard  algorithm  is an "NFA algorithm". It conducts a
+       depth-first search of the pattern tree. That is, it  proceeds  along  a
+       single path through the tree, checking that the subject matches what is
+       required. When there is a mismatch, the algorithm  tries  any  alterna-
+       tives  at  the  current point, and if they all fail, it backs up to the
+       previous branch point in the  tree,  and  tries  the  next  alternative
+       branch  at  that  level.  This often involves backing up (moving to the
+       left) in the subject string as well.  The  order  in  which  repetition
+       branches  are  tried  is controlled by the greedy or ungreedy nature of
+       the quantifier.
+
+       If a leaf node is reached, a matching string has  been  found,  and  at
+       that  point the algorithm stops. Thus, if there is more than one possi-
+       ble match, this algorithm returns the first one that it finds.  Whether
+       this  is the shortest, the longest, or some intermediate length depends
+       on the way the greedy and ungreedy repetition quantifiers are specified
+       in the pattern.
+
+       Because  it  ends  up  with a single path through the tree, it is rela-
+       tively straightforward for this algorithm to keep  track  of  the  sub-
+       strings  that  are  matched  by portions of the pattern in parentheses.
+       This provides support for capturing parentheses and back references.
+
+
+THE ALTERNATIVE MATCHING ALGORITHM
+
+       This algorithm conducts a breadth-first search of  the  tree.  Starting
+       from  the  first  matching  point  in the subject, it scans the subject
+       string from left to right, once, character by character, and as it does
+       this,  it remembers all the paths through the tree that represent valid
+       matches. In Friedl's terminology, this is a kind  of  "DFA  algorithm",
+       though  it is not implemented as a traditional finite state machine (it
+       keeps multiple states active simultaneously).
+
+       Although the general principle of this matching algorithm  is  that  it
+       scans  the subject string only once, without backtracking, there is one
+       exception: when a lookaround assertion is encountered,  the  characters
+       following  or  preceding  the  current  point  have to be independently
+       inspected.
+
+       The scan continues until either the end of the subject is  reached,  or
+       there  are  no more unterminated paths. At this point, terminated paths
+       represent the different matching possibilities (if there are none,  the
+       match  has  failed).   Thus,  if there is more than one possible match,
+       this algorithm finds all of them, and in particular, it finds the long-
+       est.  The  matches are returned in decreasing order of length. There is
+       an option to stop the algorithm after the first match (which is  neces-
+       sarily the shortest) is found.
+
+       Note that all the matches that are found start at the same point in the
+       subject. If the pattern
+
+         cat(er(pillar)?)?
+
+       is matched against the string "the caterpillar catchment",  the  result
+       will  be the three strings "caterpillar", "cater", and "cat" that start
+       at the fifth character of the subject. The algorithm does not automati-
+       cally move on to find matches that start at later positions.
+
+       PCRE's  "auto-possessification" optimization usually applies to charac-
+       ter repeats at the end of a pattern (as well as internally). For  exam-
+       ple, the pattern "a\d+" is compiled as if it were "a\d++" because there
+       is no point even considering the possibility of backtracking  into  the
+       repeated  digits.  For  DFA matching, this means that only one possible
+       match is found. If you really do want multiple matches in  such  cases,
+       either use an ungreedy repeat ("a\d+?") or set the PCRE_NO_AUTO_POSSESS
+       option when compiling.
+
+       There are a number of features of PCRE regular expressions that are not
+       supported by the alternative matching algorithm. They are as follows:
+
+       1.  Because  the  algorithm  finds  all possible matches, the greedy or
+       ungreedy nature of repetition quantifiers is not relevant.  Greedy  and
+       ungreedy quantifiers are treated in exactly the same way. However, pos-
+       sessive quantifiers can make a difference when what follows could  also
+       match what is quantified, for example in a pattern like this:
+
+         ^a++\w!
+
+       This  pattern matches "aaab!" but not "aaa!", which would be matched by
+       a non-possessive quantifier. Similarly, if an atomic group is  present,
+       it  is matched as if it were a standalone pattern at the current point,
+       and the longest match is then "locked in" for the rest of  the  overall
+       pattern.
+
+       2. When dealing with multiple paths through the tree simultaneously, it
+       is not straightforward to keep track of  captured  substrings  for  the
+       different  matching  possibilities,  and  PCRE's implementation of this
+       algorithm does not attempt to do this. This means that no captured sub-
+       strings are available.
+
+       3.  Because no substrings are captured, back references within the pat-
+       tern are not supported, and cause errors if encountered.
+
+       4. For the same reason, conditional expressions that use  a  backrefer-
+       ence  as  the  condition or test for a specific group recursion are not
+       supported.
+
+       5. Because many paths through the tree may be  active,  the  \K  escape
+       sequence, which resets the start of the match when encountered (but may
+       be on some paths and not on others), is not  supported.  It  causes  an
+       error if encountered.
+
+       6.  Callouts  are  supported, but the value of the capture_top field is
+       always 1, and the value of the capture_last field is always -1.
+
+       7. The \C escape sequence, which (in  the  standard  algorithm)  always
+       matches  a  single data unit, even in UTF-8, UTF-16 or UTF-32 modes, is
+       not supported in these modes, because the alternative  algorithm  moves
+       through the subject string one character (not data unit) at a time, for
+       all active paths through the tree.
+
+       8. Except for (*FAIL), the backtracking control verbs such as  (*PRUNE)
+       are  not  supported.  (*FAIL)  is supported, and behaves like a failing
+       negative assertion.
+
+
+ADVANTAGES OF THE ALTERNATIVE ALGORITHM
+
+       Using the alternative matching algorithm provides the following  advan-
+       tages:
+
+       1. All possible matches (at a single point in the subject) are automat-
+       ically found, and in particular, the longest match is  found.  To  find
+       more than one match using the standard algorithm, you have to do kludgy
+       things with callouts.
+
+       2. Because the alternative algorithm  scans  the  subject  string  just
+       once, and never needs to backtrack (except for lookbehinds), it is pos-
+       sible to pass very long subject strings to  the  matching  function  in
+       several pieces, checking for partial matching each time. Although it is
+       possible to do multi-segment matching using the standard  algorithm  by
+       retaining  partially  matched  substrings,  it is more complicated. The
+       pcrepartial documentation gives details of partial  matching  and  dis-
+       cusses multi-segment matching.
+
+
+DISADVANTAGES OF THE ALTERNATIVE ALGORITHM
+
+       The alternative algorithm suffers from a number of disadvantages:
+
+       1.  It  is  substantially  slower  than the standard algorithm. This is
+       partly because it has to search for all possible matches, but  is  also
+       because it is less susceptible to optimization.
+
+       2. Capturing parentheses and back references are not supported.
+
+       3. Although atomic groups are supported, their use does not provide the
+       performance advantage that it does for the standard algorithm.
+
+
+AUTHOR
+
+       Philip Hazel
+       University Computing Service
+       Cambridge CB2 3QH, England.
+
+
+REVISION
+
+       Last updated: 12 November 2013
+       Copyright (c) 1997-2012 University of Cambridge.
+------------------------------------------------------------------------------
+
+
+PCREAPI(3)                 Library Functions Manual                 PCREAPI(3)
+
+
+
+NAME
+       PCRE - Perl-compatible regular expressions
+
+       #include <pcre.h>
+
+
+PCRE NATIVE API BASIC FUNCTIONS
+
+       pcre *pcre_compile(const char *pattern, int options,
+            const char **errptr, int *erroffset,
+            const unsigned char *tableptr);
+
+       pcre *pcre_compile2(const char *pattern, int options,
+            int *errorcodeptr,
+            const char **errptr, int *erroffset,
+            const unsigned char *tableptr);
+
+       pcre_extra *pcre_study(const pcre *code, int options,
+            const char **errptr);
+
+       void pcre_free_study(pcre_extra *extra);
+
+       int pcre_exec(const pcre *code, const pcre_extra *extra,
+            const char *subject, int length, int startoffset,
+            int options, int *ovector, int ovecsize);
+
+       int pcre_dfa_exec(const pcre *code, const pcre_extra *extra,
+            const char *subject, int length, int startoffset,
+            int options, int *ovector, int ovecsize,
+            int *workspace, int wscount);
+
+
+PCRE NATIVE API STRING EXTRACTION FUNCTIONS
+
+       int pcre_copy_named_substring(const pcre *code,
+            const char *subject, int *ovector,
+            int stringcount, const char *stringname,
+            char *buffer, int buffersize);
+
+       int pcre_copy_substring(const char *subject, int *ovector,
+            int stringcount, int stringnumber, char *buffer,
+            int buffersize);
+
+       int pcre_get_named_substring(const pcre *code,
+            const char *subject, int *ovector,
+            int stringcount, const char *stringname,
+            const char **stringptr);
+
+       int pcre_get_stringnumber(const pcre *code,
+            const char *name);
+
+       int pcre_get_stringtable_entries(const pcre *code,
+            const char *name, char **first, char **last);
+
+       int pcre_get_substring(const char *subject, int *ovector,
+            int stringcount, int stringnumber,
+            const char **stringptr);
+
+       int pcre_get_substring_list(const char *subject,
+            int *ovector, int stringcount, const char ***listptr);
+
+       void pcre_free_substring(const char *stringptr);
+
+       void pcre_free_substring_list(const char **stringptr);
+
+
+PCRE NATIVE API AUXILIARY FUNCTIONS
+
+       int pcre_jit_exec(const pcre *code, const pcre_extra *extra,
+            const char *subject, int length, int startoffset,
+            int options, int *ovector, int ovecsize,
+            pcre_jit_stack *jstack);
+
+       pcre_jit_stack *pcre_jit_stack_alloc(int startsize, int maxsize);
+
+       void pcre_jit_stack_free(pcre_jit_stack *stack);
+
+       void pcre_assign_jit_stack(pcre_extra *extra,
+            pcre_jit_callback callback, void *data);
+
+       const unsigned char *pcre_maketables(void);
+
+       int pcre_fullinfo(const pcre *code, const pcre_extra *extra,
+            int what, void *where);
+
+       int pcre_refcount(pcre *code, int adjust);
+
+       int pcre_config(int what, void *where);
+
+       const char *pcre_version(void);
+
+       int pcre_pattern_to_host_byte_order(pcre *code,
+            pcre_extra *extra, const unsigned char *tables);
+
+
+PCRE NATIVE API INDIRECTED FUNCTIONS
+
+       void *(*pcre_malloc)(size_t);
+
+       void (*pcre_free)(void *);
+
+       void *(*pcre_stack_malloc)(size_t);
+
+       void (*pcre_stack_free)(void *);
+
+       int (*pcre_callout)(pcre_callout_block *);
+
+       int (*pcre_stack_guard)(void);
+
+
+PCRE 8-BIT, 16-BIT, AND 32-BIT LIBRARIES
+
+       As  well  as  support  for  8-bit character strings, PCRE also supports
+       16-bit strings (from release 8.30) and  32-bit  strings  (from  release
+       8.32),  by means of two additional libraries. They can be built as well
+       as, or instead of, the 8-bit library. To avoid too  much  complication,
+       this  document describes the 8-bit versions of the functions, with only
+       occasional references to the 16-bit and 32-bit libraries.
+
+       The 16-bit and 32-bit functions operate in the same way as their  8-bit
+       counterparts;  they  just  use different data types for their arguments
+       and results, and their names start with pcre16_ or pcre32_  instead  of
+       pcre_.  For  every  option  that  has  UTF8  in  its name (for example,
+       PCRE_UTF8), there are corresponding 16-bit and 32-bit names  with  UTF8
+       replaced by UTF16 or UTF32, respectively. This facility is in fact just
+       cosmetic; the 16-bit and 32-bit option names define the same  bit  val-
+       ues.
+
+       References to bytes and UTF-8 in this document should be read as refer-
+       ences to 16-bit data units and UTF-16 when using the 16-bit library, or
+       32-bit  data  units  and  UTF-32  when using the 32-bit library, unless
+       specified otherwise.  More details of the specific differences for  the
+       16-bit and 32-bit libraries are given in the pcre16 and pcre32 pages.
+
+
+PCRE API OVERVIEW
+
+       PCRE has its own native API, which is described in this document. There
+       are also some wrapper functions (for the 8-bit library only) that  cor-
+       respond  to  the  POSIX  regular  expression  API, but they do not give
+       access to all the functionality. They are described  in  the  pcreposix
+       documentation.  Both  of these APIs define a set of C function calls. A
+       C++ wrapper (again for the 8-bit library only) is also distributed with
+       PCRE. It is documented in the pcrecpp page.
+
+       The  native  API  C  function prototypes are defined in the header file
+       pcre.h, and on Unix-like systems the (8-bit) library itself  is  called
+       libpcre.  It  can  normally be accessed by adding -lpcre to the command
+       for linking an application that uses PCRE. The header file defines  the
+       macros PCRE_MAJOR and PCRE_MINOR to contain the major and minor release
+       numbers for the library. Applications can use these to include  support
+       for different releases of PCRE.
+
+       In a Windows environment, if you want to statically link an application
+       program against a non-dll pcre.a  file,  you  must  define  PCRE_STATIC
+       before  including  pcre.h or pcrecpp.h, because otherwise the pcre_mal-
+       loc()   and   pcre_free()   exported   functions   will   be   declared
+       __declspec(dllimport), with unwanted results.
+
+       The   functions   pcre_compile(),  pcre_compile2(),  pcre_study(),  and
+       pcre_exec() are used for compiling and matching regular expressions  in
+       a  Perl-compatible  manner. A sample program that demonstrates the sim-
+       plest way of using them is provided in the file  called  pcredemo.c  in
+       the PCRE source distribution. A listing of this program is given in the
+       pcredemo documentation, and the pcresample documentation describes  how
+       to compile and run it.
+
+       Just-in-time  compiler  support is an optional feature of PCRE that can
+       be built in appropriate hardware environments. It greatly speeds up the
+       matching  performance  of  many  patterns.  Simple  programs can easily
+       request that it be used if available, by  setting  an  option  that  is
+       ignored  when  it is not relevant. More complicated programs might need
+       to    make    use    of    the    functions     pcre_jit_stack_alloc(),
+       pcre_jit_stack_free(),  and pcre_assign_jit_stack() in order to control
+       the JIT code's memory usage.
+
+       From release 8.32 there is also a direct interface for  JIT  execution,
+       which  gives  improved performance. The JIT-specific functions are dis-
+       cussed in the pcrejit documentation.
+
+       A second matching function, pcre_dfa_exec(), which is not Perl-compati-
+       ble,  is  also provided. This uses a different algorithm for the match-
+       ing. The alternative algorithm finds all possible matches (at  a  given
+       point  in  the  subject), and scans the subject just once (unless there
+       are lookbehind assertions). However, this  algorithm  does  not  return
+       captured  substrings.  A description of the two matching algorithms and
+       their advantages and disadvantages is given in the  pcrematching  docu-
+       mentation.
+
+       In  addition  to  the  main compiling and matching functions, there are
+       convenience functions for extracting captured substrings from a subject
+       string that is matched by pcre_exec(). They are:
+
+         pcre_copy_substring()
+         pcre_copy_named_substring()
+         pcre_get_substring()
+         pcre_get_named_substring()
+         pcre_get_substring_list()
+         pcre_get_stringnumber()
+         pcre_get_stringtable_entries()
+
+       pcre_free_substring() and pcre_free_substring_list() are also provided,
+       to free the memory used for extracted strings.
+
+       The function pcre_maketables() is used to  build  a  set  of  character
+       tables   in   the   current   locale  for  passing  to  pcre_compile(),
+       pcre_exec(), or pcre_dfa_exec(). This is an optional facility  that  is
+       provided  for  specialist  use.  Most  commonly,  no special tables are
+       passed, in which case internal tables that are generated when  PCRE  is
+       built are used.
+
+       The  function  pcre_fullinfo()  is used to find out information about a
+       compiled pattern. The function pcre_version() returns a  pointer  to  a
+       string containing the version of PCRE and its date of release.
+
+       The  function  pcre_refcount()  maintains  a  reference count in a data
+       block containing a compiled pattern. This is provided for  the  benefit
+       of object-oriented applications.
+
+       The  global  variables  pcre_malloc and pcre_free initially contain the
+       entry points of the standard malloc()  and  free()  functions,  respec-
+       tively. PCRE calls the memory management functions via these variables,
+       so a calling program can replace them if it  wishes  to  intercept  the
+       calls. This should be done before calling any PCRE functions.
+
+       The  global  variables  pcre_stack_malloc  and pcre_stack_free are also
+       indirections to memory management functions.  These  special  functions
+       are  used  only  when  PCRE is compiled to use the heap for remembering
+       data, instead of recursive function calls, when running the pcre_exec()
+       function.  See  the  pcrebuild  documentation  for details of how to do
+       this. It is a non-standard way of building PCRE, for  use  in  environ-
+       ments  that  have  limited stacks. Because of the greater use of memory
+       management, it runs more slowly. Separate  functions  are  provided  so
+       that  special-purpose  external  code  can  be used for this case. When
+       used, these functions are always called in a  stack-like  manner  (last
+       obtained,  first freed), and always for memory blocks of the same size.
+       There is a discussion about PCRE's stack usage in the  pcrestack  docu-
+       mentation.
+
+       The global variable pcre_callout initially contains NULL. It can be set
+       by the caller to a "callout" function, which PCRE  will  then  call  at
+       specified  points during a matching operation. Details are given in the
+       pcrecallout documentation.
+
+       The global variable pcre_stack_guard initially contains NULL. It can be
+       set  by  the  caller  to  a function that is called by PCRE whenever it
+       starts to compile a parenthesized part of a pattern.  When  parentheses
+       are nested, PCRE uses recursive function calls, which use up the system
+       stack. This function is provided so that applications  with  restricted
+       stacks  can  force a compilation error if the stack runs out. The func-
+       tion should return zero if all is well, or non-zero to force an error.
+
+
+NEWLINES
+
+       PCRE supports five different conventions for indicating line breaks  in
+       strings:  a  single  CR (carriage return) character, a single LF (line-
+       feed) character, the two-character sequence CRLF, any of the three pre-
+       ceding,  or any Unicode newline sequence. The Unicode newline sequences
+       are the three just mentioned, plus the single characters  VT  (vertical
+       tab, U+000B), FF (form feed, U+000C), NEL (next line, U+0085), LS (line
+       separator, U+2028), and PS (paragraph separator, U+2029).
+
+       Each of the first three conventions is used by at least  one  operating
+       system  as its standard newline sequence. When PCRE is built, a default
+       can be specified.  The default default is LF, which is the  Unix  stan-
+       dard.  When  PCRE  is run, the default can be overridden, either when a
+       pattern is compiled, or when it is matched.
+
+       At compile time, the newline convention can be specified by the options
+       argument  of  pcre_compile(), or it can be specified by special text at
+       the start of the pattern itself; this overrides any other settings. See
+       the pcrepattern page for details of the special character sequences.
+
+       In the PCRE documentation the word "newline" is used to mean "the char-
+       acter or pair of characters that indicate a line break". The choice  of
+       newline  convention  affects  the  handling of the dot, circumflex, and
+       dollar metacharacters, the handling of #-comments in /x mode, and, when
+       CRLF  is a recognized line ending sequence, the match position advance-
+       ment for a non-anchored pattern. There is more detail about this in the
+       section on pcre_exec() options below.
+
+       The  choice of newline convention does not affect the interpretation of
+       the \n or \r escape sequences, nor does  it  affect  what  \R  matches,
+       which is controlled in a similar way, but by separate options.
+
+
+MULTITHREADING
+
+       The  PCRE  functions  can be used in multi-threading applications, with
+       the  proviso  that  the  memory  management  functions  pointed  to  by
+       pcre_malloc, pcre_free, pcre_stack_malloc, and pcre_stack_free, and the
+       callout and stack-checking functions pointed  to  by  pcre_callout  and
+       pcre_stack_guard, are shared by all threads.
+
+       The  compiled form of a regular expression is not altered during match-
+       ing, so the same compiled pattern can safely be used by several threads
+       at once.
+
+       If  the just-in-time optimization feature is being used, it needs sepa-
+       rate memory stack areas for each thread. See the pcrejit  documentation
+       for more details.
+
+
+SAVING PRECOMPILED PATTERNS FOR LATER USE
+
+       The compiled form of a regular expression can be saved and re-used at a
+       later time, possibly by a different program, and even on a  host  other
+       than  the  one  on  which  it  was  compiled.  Details are given in the
+       pcreprecompile documentation,  which  includes  a  description  of  the
+       pcre_pattern_to_host_byte_order()  function. However, compiling a regu-
+       lar expression with one version of PCRE for use with a  different  ver-
+       sion is not guaranteed to work and may cause crashes.
+
+
+CHECKING BUILD-TIME OPTIONS
+
+       int pcre_config(int what, void *where);
+
+       The  function pcre_config() makes it possible for a PCRE client to dis-
+       cover which optional features have been compiled into the PCRE library.
+       The  pcrebuild documentation has more details about these optional fea-
+       tures.
+
+       The first argument for pcre_config() is an  integer,  specifying  which
+       information is required; the second argument is a pointer to a variable
+       into which the information is placed. The returned  value  is  zero  on
+       success,  or  the negative error code PCRE_ERROR_BADOPTION if the value
+       in the first argument is not recognized. The following  information  is
+       available:
+
+         PCRE_CONFIG_UTF8
+
+       The  output is an integer that is set to one if UTF-8 support is avail-
+       able; otherwise it is set to zero. This value should normally be  given
+       to the 8-bit version of this function, pcre_config(). If it is given to
+       the  16-bit  or  32-bit  version  of  this  function,  the  result   is
+       PCRE_ERROR_BADOPTION.
+
+         PCRE_CONFIG_UTF16
+
+       The output is an integer that is set to one if UTF-16 support is avail-
+       able; otherwise it is set to zero. This value should normally be  given
+       to the 16-bit version of this function, pcre16_config(). If it is given
+       to the 8-bit  or  32-bit  version  of  this  function,  the  result  is
+       PCRE_ERROR_BADOPTION.
+
+         PCRE_CONFIG_UTF32
+
+       The output is an integer that is set to one if UTF-32 support is avail-
+       able; otherwise it is set to zero. This value should normally be  given
+       to the 32-bit version of this function, pcre32_config(). If it is given
+       to the 8-bit  or  16-bit  version  of  this  function,  the  result  is
+       PCRE_ERROR_BADOPTION.
+
+         PCRE_CONFIG_UNICODE_PROPERTIES
+
+       The  output  is  an  integer  that is set to one if support for Unicode
+       character properties is available; otherwise it is set to zero.
+
+         PCRE_CONFIG_JIT
+
+       The output is an integer that is set to one if support for just-in-time
+       compiling is available; otherwise it is set to zero.
+
+         PCRE_CONFIG_JITTARGET
+
+       The  output is a pointer to a zero-terminated "const char *" string. If
+       JIT support is available, the string contains the name of the architec-
+       ture  for  which the JIT compiler is configured, for example "x86 32bit
+       (little endian + unaligned)". If JIT  support  is  not  available,  the
+       result is NULL.
+
+         PCRE_CONFIG_NEWLINE
+
+       The  output  is  an integer whose value specifies the default character
+       sequence that is recognized as meaning "newline". The values  that  are
+       supported in ASCII/Unicode environments are: 10 for LF, 13 for CR, 3338
+       for CRLF, -2 for ANYCRLF, and -1 for ANY. In EBCDIC  environments,  CR,
+       ANYCRLF,  and  ANY  yield the same values. However, the value for LF is
+       normally 21, though some EBCDIC environments use 37. The  corresponding
+       values  for  CRLF are 3349 and 3365. The default should normally corre-
+       spond to the standard sequence for your operating system.
+
+         PCRE_CONFIG_BSR
+
+       The output is an integer whose value indicates what character sequences
+       the  \R  escape sequence matches by default. A value of 0 means that \R
+       matches any Unicode line ending sequence; a value of 1  means  that  \R
+       matches only CR, LF, or CRLF. The default can be overridden when a pat-
+       tern is compiled or matched.
+
+         PCRE_CONFIG_LINK_SIZE
+
+       The output is an integer that contains the number  of  bytes  used  for
+       internal  linkage  in  compiled  regular  expressions.  For  the  8-bit
+       library, the value can be 2, 3, or 4. For the 16-bit library, the value
+       is  either  2  or  4  and  is  still  a number of bytes. For the 32-bit
+       library, the value is either 2 or 4 and is still a number of bytes. The
+       default value of 2 is sufficient for all but the most massive patterns,
+       since it allows the compiled pattern to be up to 64K  in  size.  Larger
+       values  allow larger regular expressions to be compiled, at the expense
+       of slower matching.
+
+         PCRE_CONFIG_POSIX_MALLOC_THRESHOLD
+
+       The output is an integer that contains the threshold  above  which  the
+       POSIX  interface  uses malloc() for output vectors. Further details are
+       given in the pcreposix documentation.
+
+         PCRE_CONFIG_PARENS_LIMIT
+
+       The output is a long integer that gives the maximum depth of nesting of
+       parentheses  (of  any  kind) in a pattern. This limit is imposed to cap
+       the amount of system stack used when a pattern is compiled. It is spec-
+       ified  when PCRE is built; the default is 250. This limit does not take
+       into account the stack that may already be used by the calling applica-
+       tion.  For  finer  control  over compilation stack usage, you can set a
+       pointer to an external checking function in pcre_stack_guard.
+
+         PCRE_CONFIG_MATCH_LIMIT
+
+       The output is a long integer that gives the default limit for the  num-
+       ber  of  internal  matching  function calls in a pcre_exec() execution.
+       Further details are given with pcre_exec() below.
+
+         PCRE_CONFIG_MATCH_LIMIT_RECURSION
+
+       The output is a long integer that gives the default limit for the depth
+       of   recursion  when  calling  the  internal  matching  function  in  a
+       pcre_exec() execution.  Further  details  are  given  with  pcre_exec()
+       below.
+
+         PCRE_CONFIG_STACKRECURSE
+
+       The  output is an integer that is set to one if internal recursion when
+       running pcre_exec() is implemented by recursive function calls that use
+       the  stack  to remember their state. This is the usual way that PCRE is
+       compiled. The output is zero if PCRE was compiled to use blocks of data
+       on  the  heap  instead  of  recursive  function  calls.  In  this case,
+       pcre_stack_malloc and  pcre_stack_free  are  called  to  manage  memory
+       blocks on the heap, thus avoiding the use of the stack.
+
+
+COMPILING A PATTERN
+
+       pcre *pcre_compile(const char *pattern, int options,
+            const char **errptr, int *erroffset,
+            const unsigned char *tableptr);
+
+       pcre *pcre_compile2(const char *pattern, int options,
+            int *errorcodeptr,
+            const char **errptr, int *erroffset,
+            const unsigned char *tableptr);
+
+       Either of the functions pcre_compile() or pcre_compile2() can be called
+       to compile a pattern into an internal form. The only difference between
+       the  two interfaces is that pcre_compile2() has an additional argument,
+       errorcodeptr, via which a numerical error  code  can  be  returned.  To
+       avoid  too  much repetition, we refer just to pcre_compile() below, but
+       the information applies equally to pcre_compile2().
+
+       The pattern is a C string terminated by a binary zero, and is passed in
+       the  pattern  argument.  A  pointer to a single block of memory that is
+       obtained via pcre_malloc is returned. This contains the  compiled  code
+       and related data. The pcre type is defined for the returned block; this
+       is a typedef for a structure whose contents are not externally defined.
+       It is up to the caller to free the memory (via pcre_free) when it is no
+       longer required.
+
+       Although the compiled code of a PCRE regex is relocatable, that is,  it
+       does not depend on memory location, the complete pcre data block is not
+       fully relocatable, because it may contain a copy of the tableptr  argu-
+       ment, which is an address (see below).
+
+       The options argument contains various bit settings that affect the com-
+       pilation. It should be zero if no options are required.  The  available
+       options  are  described  below. Some of them (in particular, those that
+       are compatible with Perl, but some others as well) can also be set  and
+       unset  from  within  the  pattern  (see the detailed description in the
+       pcrepattern documentation). For those options that can be different  in
+       different  parts  of  the pattern, the contents of the options argument
+       specifies their settings at the start of compilation and execution. The
+       PCRE_ANCHORED,  PCRE_BSR_xxx, PCRE_NEWLINE_xxx, PCRE_NO_UTF8_CHECK, and
+       PCRE_NO_START_OPTIMIZE options can be set at the time  of  matching  as
+       well as at compile time.
+
+       If errptr is NULL, pcre_compile() returns NULL immediately.  Otherwise,
+       if compilation of a pattern fails,  pcre_compile()  returns  NULL,  and
+       sets the variable pointed to by errptr to point to a textual error mes-
+       sage. This is a static string that is part of the library. You must not
+       try  to  free it. Normally, the offset from the start of the pattern to
+       the data unit that was being processed when the error was discovered is
+       placed  in the variable pointed to by erroffset, which must not be NULL
+       (if it is, an immediate error is given). However, for an invalid  UTF-8
+       or  UTF-16  string,  the  offset  is that of the first data unit of the
+       failing character.
+
+       Some errors are not detected until the whole pattern has been  scanned;
+       in  these  cases,  the offset passed back is the length of the pattern.
+       Note that the offset is in data units, not characters, even  in  a  UTF
+       mode. It may sometimes point into the middle of a UTF-8 or UTF-16 char-
+       acter.
+
+       If pcre_compile2() is used instead of pcre_compile(),  and  the  error-
+       codeptr  argument is not NULL, a non-zero error code number is returned
+       via this argument in the event of an error. This is in addition to  the
+       textual error message. Error codes and messages are listed below.
+
+       If  the  final  argument, tableptr, is NULL, PCRE uses a default set of
+       character tables that are  built  when  PCRE  is  compiled,  using  the
+       default  C  locale.  Otherwise, tableptr must be an address that is the
+       result of a call to pcre_maketables(). This value is  stored  with  the
+       compiled  pattern,  and  used  again by pcre_exec() and pcre_dfa_exec()
+       when the pattern is matched. For more discussion, see  the  section  on
+       locale support below.
+
+       This  code  fragment  shows a typical straightforward call to pcre_com-
+       pile():
+
+         pcre *re;
+         const char *error;
+         int erroffset;
+         re = pcre_compile(
+           "^A.*Z",          /* the pattern */
+           0,                /* default options */
+           &error,           /* for error message */
+           &erroffset,       /* for error offset */
+           NULL);            /* use default character tables */
+
+       The following names for option bits are defined in  the  pcre.h  header
+       file:
+
+         PCRE_ANCHORED
+
+       If this bit is set, the pattern is forced to be "anchored", that is, it
+       is constrained to match only at the first matching point in the  string
+       that  is being searched (the "subject string"). This effect can also be
+       achieved by appropriate constructs in the pattern itself, which is  the
+       only way to do it in Perl.
+
+         PCRE_AUTO_CALLOUT
+
+       If this bit is set, pcre_compile() automatically inserts callout items,
+       all with number 255, before each pattern item. For  discussion  of  the
+       callout facility, see the pcrecallout documentation.
+
+         PCRE_BSR_ANYCRLF
+         PCRE_BSR_UNICODE
+
+       These options (which are mutually exclusive) control what the \R escape
+       sequence matches. The choice is either to match only CR, LF,  or  CRLF,
+       or to match any Unicode newline sequence. The default is specified when
+       PCRE is built. It can be overridden from within the pattern, or by set-
+       ting an option when a compiled pattern is matched.
+
+         PCRE_CASELESS
+
+       If  this  bit is set, letters in the pattern match both upper and lower
+       case letters. It is equivalent to Perl's  /i  option,  and  it  can  be
+       changed  within a pattern by a (?i) option setting. In UTF-8 mode, PCRE
+       always understands the concept of case for characters whose values  are
+       less  than 128, so caseless matching is always possible. For characters
+       with higher values, the concept of case is supported if  PCRE  is  com-
+       piled  with Unicode property support, but not otherwise. If you want to
+       use caseless matching for characters 128 and  above,  you  must  ensure
+       that  PCRE  is  compiled  with Unicode property support as well as with
+       UTF-8 support.
+
+         PCRE_DOLLAR_ENDONLY
+
+       If this bit is set, a dollar metacharacter in the pattern matches  only
+       at  the  end  of the subject string. Without this option, a dollar also
+       matches immediately before a newline at the end of the string (but  not
+       before  any  other newlines). The PCRE_DOLLAR_ENDONLY option is ignored
+       if PCRE_MULTILINE is set.  There is no equivalent  to  this  option  in
+       Perl, and no way to set it within a pattern.
+
+         PCRE_DOTALL
+
+       If  this bit is set, a dot metacharacter in the pattern matches a char-
+       acter of any value, including one that indicates a newline. However, it
+       only  ever  matches  one character, even if newlines are coded as CRLF.
+       Without this option, a dot does not match when the current position  is
+       at a newline. This option is equivalent to Perl's /s option, and it can
+       be changed within a pattern by a (?s) option setting. A negative  class
+       such as [^a] always matches newline characters, independent of the set-
+       ting of this option.
+
+         PCRE_DUPNAMES
+
+       If this bit is set, names used to identify capturing  subpatterns  need
+       not be unique. This can be helpful for certain types of pattern when it
+       is known that only one instance of the named  subpattern  can  ever  be
+       matched.  There  are  more details of named subpatterns below; see also
+       the pcrepattern documentation.
+
+         PCRE_EXTENDED
+
+       If this bit is set, most white space  characters  in  the  pattern  are
+       totally  ignored  except when escaped or inside a character class. How-
+       ever, white space is not allowed within  sequences  such  as  (?>  that
+       introduce  various  parenthesized  subpatterns,  nor within a numerical
+       quantifier such as {1,3}.  However, ignorable white space is  permitted
+       between an item and a following quantifier and between a quantifier and
+       a following + that indicates possessiveness.
+
+       White space did not used to include the VT character (code 11), because
+       Perl did not treat this character as white space. However, Perl changed
+       at release 5.18, so PCRE followed  at  release  8.34,  and  VT  is  now
+       treated as white space.
+
+       PCRE_EXTENDED  also  causes characters between an unescaped # outside a
+       character class  and  the  next  newline,  inclusive,  to  be  ignored.
+       PCRE_EXTENDED  is equivalent to Perl's /x option, and it can be changed
+       within a pattern by a (?x) option setting.
+
+       Which characters are interpreted  as  newlines  is  controlled  by  the
+       options  passed to pcre_compile() or by a special sequence at the start
+       of the pattern, as described in the section entitled  "Newline  conven-
+       tions" in the pcrepattern documentation. Note that the end of this type
+       of comment is  a  literal  newline  sequence  in  the  pattern;  escape
+       sequences that happen to represent a newline do not count.
+
+       This  option  makes  it possible to include comments inside complicated
+       patterns.  Note, however, that this applies only  to  data  characters.
+       White  space  characters  may  never  appear  within  special character
+       sequences in a pattern, for example within the sequence (?( that intro-
+       duces a conditional subpattern.
+
+         PCRE_EXTRA
+
+       This  option  was invented in order to turn on additional functionality
+       of PCRE that is incompatible with Perl, but it  is  currently  of  very
+       little  use. When set, any backslash in a pattern that is followed by a
+       letter that has no special meaning  causes  an  error,  thus  reserving
+       these  combinations  for  future  expansion.  By default, as in Perl, a
+       backslash followed by a letter with no special meaning is treated as  a
+       literal. (Perl can, however, be persuaded to give an error for this, by
+       running it with the -w option.) There are at present no other  features
+       controlled  by this option. It can also be set by a (?X) option setting
+       within a pattern.
+
+         PCRE_FIRSTLINE
+
+       If this option is set, an  unanchored  pattern  is  required  to  match
+       before  or  at  the  first  newline  in  the subject string, though the
+       matched text may continue over the newline.
+
+         PCRE_JAVASCRIPT_COMPAT
+
+       If this option is set, PCRE's behaviour is changed in some ways so that
+       it  is  compatible with JavaScript rather than Perl. The changes are as
+       follows:
+
+       (1) A lone closing square bracket in a pattern  causes  a  compile-time
+       error,  because this is illegal in JavaScript (by default it is treated
+       as a data character). Thus, the pattern AB]CD becomes illegal when this
+       option is set.
+
+       (2)  At run time, a back reference to an unset subpattern group matches
+       an empty string (by default this causes the current  matching  alterna-
+       tive  to  fail). A pattern such as (\1)(a) succeeds when this option is
+       set (assuming it can find an "a" in the subject), whereas it  fails  by
+       default, for Perl compatibility.
+
+       (3) \U matches an upper case "U" character; by default \U causes a com-
+       pile time error (Perl uses \U to upper case subsequent characters).
+
+       (4) \u matches a lower case "u" character unless it is followed by four
+       hexadecimal  digits,  in  which case the hexadecimal number defines the
+       code point to match. By default, \u causes a compile time  error  (Perl
+       uses it to upper case the following character).
+
+       (5)  \x matches a lower case "x" character unless it is followed by two
+       hexadecimal digits, in which case the hexadecimal  number  defines  the
+       code  point  to  match. By default, as in Perl, a hexadecimal number is
+       always expected after \x, but it may have zero, one, or two digits (so,
+       for example, \xz matches a binary zero character followed by z).
+
+         PCRE_MULTILINE
+
+       By  default,  for  the purposes of matching "start of line" and "end of
+       line", PCRE treats the subject string as consisting of a single line of
+       characters,  even if it actually contains newlines. The "start of line"
+       metacharacter (^) matches only at the start of the string, and the "end
+       of  line"  metacharacter  ($) matches only at the end of the string, or
+       before a terminating newline (except when PCRE_DOLLAR_ENDONLY is  set).
+       Note,  however,  that  unless  PCRE_DOTALL  is set, the "any character"
+       metacharacter (.) does not match at a newline. This behaviour  (for  ^,
+       $, and dot) is the same as Perl.
+
+       When  PCRE_MULTILINE  it  is set, the "start of line" and "end of line"
+       constructs match immediately following or immediately  before  internal
+       newlines  in  the  subject string, respectively, as well as at the very
+       start and end. This is equivalent to Perl's /m option, and  it  can  be
+       changed within a pattern by a (?m) option setting. If there are no new-
+       lines in a subject string, or no occurrences of ^ or $  in  a  pattern,
+       setting PCRE_MULTILINE has no effect.
+
+         PCRE_NEVER_UTF
+
+       This option locks out interpretation of the pattern as UTF-8 (or UTF-16
+       or UTF-32 in the 16-bit and 32-bit libraries). In particular,  it  pre-
+       vents  the  creator of the pattern from switching to UTF interpretation
+       by starting the pattern with (*UTF). This may be useful in applications
+       that  process  patterns  from  external  sources.  The  combination  of
+       PCRE_UTF8 and PCRE_NEVER_UTF also causes an error.
+
+         PCRE_NEWLINE_CR
+         PCRE_NEWLINE_LF
+         PCRE_NEWLINE_CRLF
+         PCRE_NEWLINE_ANYCRLF
+         PCRE_NEWLINE_ANY
+
+       These options override the default newline definition that  was  chosen
+       when  PCRE  was built. Setting the first or the second specifies that a
+       newline is indicated by a single character (CR  or  LF,  respectively).
+       Setting  PCRE_NEWLINE_CRLF specifies that a newline is indicated by the
+       two-character CRLF  sequence.  Setting  PCRE_NEWLINE_ANYCRLF  specifies
+       that any of the three preceding sequences should be recognized. Setting
+       PCRE_NEWLINE_ANY specifies that any Unicode newline sequence should  be
+       recognized.
+
+       In  an ASCII/Unicode environment, the Unicode newline sequences are the
+       three just mentioned, plus the  single  characters  VT  (vertical  tab,
+       U+000B), FF (form feed, U+000C), NEL (next line, U+0085), LS (line sep-
+       arator, U+2028), and PS (paragraph separator, U+2029).  For  the  8-bit
+       library, the last two are recognized only in UTF-8 mode.
+
+       When  PCRE is compiled to run in an EBCDIC (mainframe) environment, the
+       code for CR is 0x0d, the same as ASCII. However, the character code for
+       LF  is  normally 0x15, though in some EBCDIC environments 0x25 is used.
+       Whichever of these is not LF is made to  correspond  to  Unicode's  NEL
+       character.  EBCDIC  codes  are all less than 256. For more details, see
+       the pcrebuild documentation.
+
+       The newline setting in the  options  word  uses  three  bits  that  are
+       treated as a number, giving eight possibilities. Currently only six are
+       used (default plus the five values above). This means that if  you  set
+       more  than one newline option, the combination may or may not be sensi-
+       ble. For example, PCRE_NEWLINE_CR with PCRE_NEWLINE_LF is equivalent to
+       PCRE_NEWLINE_CRLF,  but other combinations may yield unused numbers and
+       cause an error.
+
+       The only time that a line break in a pattern  is  specially  recognized
+       when  compiling is when PCRE_EXTENDED is set. CR and LF are white space
+       characters, and so are ignored in this mode. Also, an unescaped #  out-
+       side  a  character class indicates a comment that lasts until after the
+       next line break sequence. In other circumstances, line break  sequences
+       in patterns are treated as literal data.
+
+       The newline option that is set at compile time becomes the default that
+       is used for pcre_exec() and pcre_dfa_exec(), but it can be overridden.
+
+         PCRE_NO_AUTO_CAPTURE
+
+       If this option is set, it disables the use of numbered capturing paren-
+       theses  in the pattern. Any opening parenthesis that is not followed by
+       ? behaves as if it were followed by ?: but named parentheses can  still
+       be  used  for  capturing  (and  they acquire numbers in the usual way).
+       There is no equivalent of this option in Perl.
+
+         PCRE_NO_AUTO_POSSESS
+
+       If this option is set, it disables "auto-possessification". This is  an
+       optimization  that,  for example, turns a+b into a++b in order to avoid
+       backtracks into a+ that can never be successful. However,  if  callouts
+       are  in  use,  auto-possessification  means that some of them are never
+       taken. You can set this option if you want the matching functions to do
+       a  full  unoptimized  search and run all the callouts, but it is mainly
+       provided for testing purposes.
+
+         PCRE_NO_START_OPTIMIZE
+
+       This is an option that acts at matching time; that is, it is really  an
+       option  for  pcre_exec()  or  pcre_dfa_exec().  If it is set at compile
+       time, it is remembered with the compiled pattern and assumed at  match-
+       ing  time.  This is necessary if you want to use JIT execution, because
+       the JIT compiler needs to know whether or not this option is  set.  For
+       details see the discussion of PCRE_NO_START_OPTIMIZE below.
+
+         PCRE_UCP
+
+       This  option changes the way PCRE processes \B, \b, \D, \d, \S, \s, \W,
+       \w, and some of the POSIX character classes.  By  default,  only  ASCII
+       characters  are  recognized, but if PCRE_UCP is set, Unicode properties
+       are used instead to classify characters. More details are given in  the
+       section  on generic character types in the pcrepattern page. If you set
+       PCRE_UCP, matching one of the items it affects takes much  longer.  The
+       option  is  available only if PCRE has been compiled with Unicode prop-
+       erty support.
+
+         PCRE_UNGREEDY
+
+       This option inverts the "greediness" of the quantifiers  so  that  they
+       are  not greedy by default, but become greedy if followed by "?". It is
+       not compatible with Perl. It can also be set by a (?U)  option  setting
+       within the pattern.
+
+         PCRE_UTF8
+
+       This  option  causes PCRE to regard both the pattern and the subject as
+       strings of UTF-8 characters instead of single-byte strings. However, it
+       is  available  only  when PCRE is built to include UTF support. If not,
+       the use of this option provokes an error. Details of  how  this  option
+       changes the behaviour of PCRE are given in the pcreunicode page.
+
+         PCRE_NO_UTF8_CHECK
+
+       When PCRE_UTF8 is set, the validity of the pattern as a UTF-8 string is
+       automatically checked. There is a  discussion  about  the  validity  of
+       UTF-8  strings in the pcreunicode page. If an invalid UTF-8 sequence is
+       found, pcre_compile() returns an error. If you already know  that  your
+       pattern  is valid, and you want to skip this check for performance rea-
+       sons, you can set the PCRE_NO_UTF8_CHECK option.  When it is  set,  the
+       effect of passing an invalid UTF-8 string as a pattern is undefined. It
+       may cause your program to crash or loop. Note that this option can also
+       be  passed to pcre_exec() and pcre_dfa_exec(), to suppress the validity
+       checking of subject strings only. If the same string is  being  matched
+       many  times, the option can be safely set for the second and subsequent
+       matchings to improve performance.
+
+
+COMPILATION ERROR CODES
+
+       The following table lists the error  codes  than  may  be  returned  by
+       pcre_compile2(),  along with the error messages that may be returned by
+       both compiling functions. Note that error  messages  are  always  8-bit
+       ASCII  strings,  even  in 16-bit or 32-bit mode. As PCRE has developed,
+       some error codes have fallen out of use. To avoid confusion, they  have
+       not been re-used.
+
+          0  no error
+          1  \ at end of pattern
+          2  \c at end of pattern
+          3  unrecognized character follows \
+          4  numbers out of order in {} quantifier
+          5  number too big in {} quantifier
+          6  missing terminating ] for character class
+          7  invalid escape sequence in character class
+          8  range out of order in character class
+          9  nothing to repeat
+         10  [this code is not in use]
+         11  internal error: unexpected repeat
+         12  unrecognized character after (? or (?-
+         13  POSIX named classes are supported only within a class
+         14  missing )
+         15  reference to non-existent subpattern
+         16  erroffset passed as NULL
+         17  unknown option bit(s) set
+         18  missing ) after comment
+         19  [this code is not in use]
+         20  regular expression is too large
+         21  failed to get memory
+         22  unmatched parentheses
+         23  internal error: code overflow
+         24  unrecognized character after (?<
+         25  lookbehind assertion is not fixed length
+         26  malformed number or name after (?(
+         27  conditional group contains more than two branches
+         28  assertion expected after (?(
+         29  (?R or (?[+-]digits must be followed by )
+         30  unknown POSIX class name
+         31  POSIX collating elements are not supported
+         32  this version of PCRE is compiled without UTF support
+         33  [this code is not in use]
+         34  character value in \x{} or \o{} is too large
+         35  invalid condition (?(0)
+         36  \C not allowed in lookbehind assertion
+         37  PCRE does not support \L, \l, \N{name}, \U, or \u
+         38  number after (?C is > 255
+         39  closing ) for (?C expected
+         40  recursive call could loop indefinitely
+         41  unrecognized character after (?P
+         42  syntax error in subpattern name (missing terminator)
+         43  two named subpatterns have the same name
+         44  invalid UTF-8 string (specifically UTF-8)
+         45  support for \P, \p, and \X has not been compiled
+         46  malformed \P or \p sequence
+         47  unknown property name after \P or \p
+         48  subpattern name is too long (maximum 32 characters)
+         49  too many named subpatterns (maximum 10000)
+         50  [this code is not in use]
+         51  octal value is greater than \377 in 8-bit non-UTF-8 mode
+         52  internal error: overran compiling workspace
+         53  internal error: previously-checked referenced subpattern
+               not found
+         54  DEFINE group contains more than one branch
+         55  repeating a DEFINE group is not allowed
+         56  inconsistent NEWLINE options
+         57  \g is not followed by a braced, angle-bracketed, or quoted
+               name/number or by a plain number
+         58  a numbered reference must not be zero
+         59  an argument is not allowed for (*ACCEPT), (*FAIL), or (*COMMIT)
+         60  (*VERB) not recognized or malformed
+         61  number is too big
+         62  subpattern name expected
+         63  digit expected after (?+
+         64  ] is an invalid data character in JavaScript compatibility mode
+         65  different names for subpatterns of the same number are
+               not allowed
+         66  (*MARK) must have an argument
+         67  this version of PCRE is not compiled with Unicode property
+               support
+         68  \c must be followed by an ASCII character
+         69  \k is not followed by a braced, angle-bracketed, or quoted name
+         70  internal error: unknown opcode in find_fixedlength()
+         71  \N is not supported in a class
+         72  too many forward references
+         73  disallowed Unicode code point (>= 0xd800 && <= 0xdfff)
+         74  invalid UTF-16 string (specifically UTF-16)
+         75  name is too long in (*MARK), (*PRUNE), (*SKIP), or (*THEN)
+         76  character value in \u.... sequence is too large
+         77  invalid UTF-32 string (specifically UTF-32)
+         78  setting UTF is disabled by the application
+         79  non-hex character in \x{} (closing brace missing?)
+         80  non-octal character in \o{} (closing brace missing?)
+         81  missing opening brace after \o
+         82  parentheses are too deeply nested
+         83  invalid range in character class
+         84  group name must start with a non-digit
+         85  parentheses are too deeply nested (stack check)
+
+       The  numbers  32  and 10000 in errors 48 and 49 are defaults; different
+       values may be used if the limits were changed when PCRE was built.
+
+
+STUDYING A PATTERN
+
+       pcre_extra *pcre_study(const pcre *code, int options,
+            const char **errptr);
+
+       If a compiled pattern is going to be used several times,  it  is  worth
+       spending more time analyzing it in order to speed up the time taken for
+       matching. The function pcre_study() takes a pointer to a compiled  pat-
+       tern as its first argument. If studying the pattern produces additional
+       information that will help speed up matching,  pcre_study()  returns  a
+       pointer  to a pcre_extra block, in which the study_data field points to
+       the results of the study.
+
+       The  returned  value  from  pcre_study()  can  be  passed  directly  to
+       pcre_exec()  or  pcre_dfa_exec(). However, a pcre_extra block also con-
+       tains other fields that can be set by the caller before  the  block  is
+       passed; these are described below in the section on matching a pattern.
+
+       If  studying  the  pattern  does  not  produce  any useful information,
+       pcre_study() returns NULL by default.  In  that  circumstance,  if  the
+       calling program wants to pass any of the other fields to pcre_exec() or
+       pcre_dfa_exec(), it must set up its own pcre_extra block.  However,  if
+       pcre_study()  is  called  with  the  PCRE_STUDY_EXTRA_NEEDED option, it
+       returns a pcre_extra block even if studying did not find any additional
+       information.  It  may still return NULL, however, if an error occurs in
+       pcre_study().
+
+       The second argument of pcre_study() contains  option  bits.  There  are
+       three further options in addition to PCRE_STUDY_EXTRA_NEEDED:
+
+         PCRE_STUDY_JIT_COMPILE
+         PCRE_STUDY_JIT_PARTIAL_HARD_COMPILE
+         PCRE_STUDY_JIT_PARTIAL_SOFT_COMPILE
+
+       If  any  of  these are set, and the just-in-time compiler is available,
+       the pattern is further compiled into machine code  that  executes  much
+       faster  than  the  pcre_exec()  interpretive  matching function. If the
+       just-in-time compiler is not available, these options are ignored.  All
+       undefined bits in the options argument must be zero.
+
+       JIT  compilation  is  a heavyweight optimization. It can take some time
+       for patterns to be analyzed, and for one-off matches  and  simple  pat-
+       terns  the benefit of faster execution might be offset by a much slower
+       study time.  Not all patterns can be optimized by the JIT compiler. For
+       those  that cannot be handled, matching automatically falls back to the
+       pcre_exec() interpreter. For more details, see the  pcrejit  documenta-
+       tion.
+
+       The  third argument for pcre_study() is a pointer for an error message.
+       If studying succeeds (even if no data is  returned),  the  variable  it
+       points  to  is  set  to NULL. Otherwise it is set to point to a textual
+       error message. This is a static string that is part of the library. You
+       must  not  try  to  free it. You should test the error pointer for NULL
+       after calling pcre_study(), to be sure that it has run successfully.
+
+       When you are finished with a pattern, you can free the memory used  for
+       the study data by calling pcre_free_study(). This function was added to
+       the API for release 8.20. For earlier versions,  the  memory  could  be
+       freed  with  pcre_free(), just like the pattern itself. This will still
+       work in cases where JIT optimization is not used, but it  is  advisable
+       to change to the new function when convenient.
+
+       This  is  a typical way in which pcre_study() is used (except that in a
+       real application there should be tests for errors):
+
+         int rc;
+         pcre *re;
+         pcre_extra *sd;
+         re = pcre_compile("pattern", 0, &error, &erroroffset, NULL);
+         sd = pcre_study(
+           re,             /* result of pcre_compile() */
+           0,              /* no options */
+           &error);        /* set to NULL or points to a message */
+         rc = pcre_exec(   /* see below for details of pcre_exec() options */
+           re, sd, "subject", 7, 0, 0, ovector, 30);
+         ...
+         pcre_free_study(sd);
+         pcre_free(re);
+
+       Studying a pattern does two things: first, a lower bound for the length
+       of subject string that is needed to match the pattern is computed. This
+       does not mean that there are any strings of that length that match, but
+       it  does  guarantee that no shorter strings match. The value is used to
+       avoid wasting time by trying to match strings that are shorter than the
+       lower  bound.  You  can find out the value in a calling program via the
+       pcre_fullinfo() function.
+
+       Studying a pattern is also useful for non-anchored patterns that do not
+       have  a  single fixed starting character. A bitmap of possible starting
+       bytes is created. This speeds up finding a position in the  subject  at
+       which to start matching. (In 16-bit mode, the bitmap is used for 16-bit
+       values less than 256.  In 32-bit mode, the bitmap is  used  for  32-bit
+       values less than 256.)
+
+       These  two optimizations apply to both pcre_exec() and pcre_dfa_exec(),
+       and the information is also used by the JIT  compiler.   The  optimiza-
+       tions  can  be  disabled  by setting the PCRE_NO_START_OPTIMIZE option.
+       You might want to do this if your pattern contains callouts or  (*MARK)
+       and  you  want  to make use of these facilities in cases where matching
+       fails.
+
+       PCRE_NO_START_OPTIMIZE can be specified at either compile time or  exe-
+       cution   time.   However,   if   PCRE_NO_START_OPTIMIZE  is  passed  to
+       pcre_exec(), (that is, after any JIT compilation has happened) JIT exe-
+       cution  is disabled. For JIT execution to work with PCRE_NO_START_OPTI-
+       MIZE, the option must be set at compile time.
+
+       There is a longer discussion of PCRE_NO_START_OPTIMIZE below.
+
+
+LOCALE SUPPORT
+
+       PCRE handles caseless matching, and determines whether  characters  are
+       letters,  digits, or whatever, by reference to a set of tables, indexed
+       by character code point. When running in UTF-8 mode, or in the  16-  or
+       32-bit libraries, this applies only to characters with code points less
+       than 256. By default, higher-valued code  points  never  match  escapes
+       such  as \w or \d. However, if PCRE is built with Unicode property sup-
+       port, all characters can be tested with \p and \P,  or,  alternatively,
+       the  PCRE_UCP option can be set when a pattern is compiled; this causes
+       \w and friends to use Unicode property support instead of the  built-in
+       tables.
+
+       The  use  of  locales  with Unicode is discouraged. If you are handling
+       characters with code points greater than 128,  you  should  either  use
+       Unicode support, or use locales, but not try to mix the two.
+
+       PCRE  contains  an  internal set of tables that are used when the final
+       argument of pcre_compile() is  NULL.  These  are  sufficient  for  many
+       applications.  Normally, the internal tables recognize only ASCII char-
+       acters. However, when PCRE is built, it is possible to cause the inter-
+       nal tables to be rebuilt in the default "C" locale of the local system,
+       which may cause them to be different.
+
+       The internal tables can always be overridden by tables supplied by  the
+       application that calls PCRE. These may be created in a different locale
+       from the default. As more and more applications change  to  using  Uni-
+       code, the need for this locale support is expected to die away.
+
+       External  tables  are  built by calling the pcre_maketables() function,
+       which has no arguments, in the relevant locale. The result can then  be
+       passed  to  pcre_compile() as often as necessary. For example, to build
+       and use tables that  are  appropriate  for  the  French  locale  (where
+       accented  characters  with  values greater than 128 are treated as let-
+       ters), the following code could be used:
+
+         setlocale(LC_CTYPE, "fr_FR");
+         tables = pcre_maketables();
+         re = pcre_compile(..., tables);
+
+       The locale name "fr_FR" is used on Linux and other  Unix-like  systems;
+       if you are using Windows, the name for the French locale is "french".
+
+       When  pcre_maketables()  runs,  the  tables are built in memory that is
+       obtained via pcre_malloc. It is the caller's responsibility  to  ensure
+       that  the memory containing the tables remains available for as long as
+       it is needed.
+
+       The pointer that is passed to pcre_compile() is saved with the compiled
+       pattern,  and the same tables are used via this pointer by pcre_study()
+       and also by pcre_exec() and pcre_dfa_exec(). Thus, for any single  pat-
+       tern, compilation, studying and matching all happen in the same locale,
+       but different patterns can be processed in different locales.
+
+       It is possible to pass a table pointer or NULL (indicating the  use  of
+       the internal tables) to pcre_exec() or pcre_dfa_exec() (see the discus-
+       sion below in the section on matching a pattern). This facility is pro-
+       vided  for  use  with  pre-compiled  patterns  that have been saved and
+       reloaded.  Character tables are not saved with patterns, so if  a  non-
+       standard table was used at compile time, it must be provided again when
+       the reloaded pattern is matched. Attempting to  use  this  facility  to
+       match a pattern in a different locale from the one in which it was com-
+       piled is likely to lead to anomalous (usually incorrect) results.
+
+
+INFORMATION ABOUT A PATTERN
+
+       int pcre_fullinfo(const pcre *code, const pcre_extra *extra,
+            int what, void *where);
+
+       The pcre_fullinfo() function returns information about a compiled  pat-
+       tern.  It replaces the pcre_info() function, which was removed from the
+       library at version 8.30, after more than 10 years of obsolescence.
+
+       The first argument for pcre_fullinfo() is a  pointer  to  the  compiled
+       pattern.  The second argument is the result of pcre_study(), or NULL if
+       the pattern was not studied. The third argument specifies  which  piece
+       of  information  is required, and the fourth argument is a pointer to a
+       variable to receive the data. The yield of the  function  is  zero  for
+       success, or one of the following negative numbers:
+
+         PCRE_ERROR_NULL           the argument code was NULL
+                                   the argument where was NULL
+         PCRE_ERROR_BADMAGIC       the "magic number" was not found
+         PCRE_ERROR_BADENDIANNESS  the pattern was compiled with different
+                                   endianness
+         PCRE_ERROR_BADOPTION      the value of what was invalid
+         PCRE_ERROR_UNSET          the requested field is not set
+
+       The  "magic  number" is placed at the start of each compiled pattern as
+       an simple check against passing an arbitrary memory pointer. The  endi-
+       anness error can occur if a compiled pattern is saved and reloaded on a
+       different host. Here is a typical call of  pcre_fullinfo(),  to  obtain
+       the length of the compiled pattern:
+
+         int rc;
+         size_t length;
+         rc = pcre_fullinfo(
+           re,               /* result of pcre_compile() */
+           sd,               /* result of pcre_study(), or NULL */
+           PCRE_INFO_SIZE,   /* what is required */
+           &length);         /* where to put the data */
+
+       The  possible  values for the third argument are defined in pcre.h, and
+       are as follows:
+
+         PCRE_INFO_BACKREFMAX
+
+       Return the number of the highest back reference  in  the  pattern.  The
+       fourth  argument  should  point to an int variable. Zero is returned if
+       there are no back references.
+
+         PCRE_INFO_CAPTURECOUNT
+
+       Return the number of capturing subpatterns in the pattern.  The  fourth
+       argument should point to an int variable.
+
+         PCRE_INFO_DEFAULT_TABLES
+
+       Return  a pointer to the internal default character tables within PCRE.
+       The fourth argument should point to an unsigned char *  variable.  This
+       information call is provided for internal use by the pcre_study() func-
+       tion. External callers can cause PCRE to use  its  internal  tables  by
+       passing a NULL table pointer.
+
+         PCRE_INFO_FIRSTBYTE (deprecated)
+
+       Return information about the first data unit of any matched string, for
+       a non-anchored pattern. The name of this option  refers  to  the  8-bit
+       library,  where  data units are bytes. The fourth argument should point
+       to an int variable. Negative values are used for  special  cases.  How-
+       ever,  this  means  that when the 32-bit library is in non-UTF-32 mode,
+       the full 32-bit range of characters cannot be returned. For  this  rea-
+       son,  this  value  is deprecated; use PCRE_INFO_FIRSTCHARACTERFLAGS and
+       PCRE_INFO_FIRSTCHARACTER instead.
+
+       If there is a fixed first value, for example, the  letter  "c"  from  a
+       pattern  such  as (cat|cow|coyote), its value is returned. In the 8-bit
+       library, the value is always less than 256. In the 16-bit  library  the
+       value can be up to 0xffff. In the 32-bit library the value can be up to
+       0x10ffff.
+
+       If there is no fixed first value, and if either
+
+       (a) the pattern was compiled with the PCRE_MULTILINE option, and  every
+       branch starts with "^", or
+
+       (b) every branch of the pattern starts with ".*" and PCRE_DOTALL is not
+       set (if it were set, the pattern would be anchored),
+
+       -1 is returned, indicating that the pattern matches only at  the  start
+       of  a  subject string or after any newline within the string. Otherwise
+       -2 is returned. For anchored patterns, -2 is returned.
+
+         PCRE_INFO_FIRSTCHARACTER
+
+       Return the value of the first data  unit  (non-UTF  character)  of  any
+       matched  string  in  the  situation where PCRE_INFO_FIRSTCHARACTERFLAGS
+       returns 1; otherwise return 0. The fourth argument should point  to  an
+       uint_t variable.
+
+       In  the 8-bit library, the value is always less than 256. In the 16-bit
+       library the value can be up to 0xffff. In the 32-bit library in  UTF-32
+       mode  the  value  can  be up to 0x10ffff, and up to 0xffffffff when not
+       using UTF-32 mode.
+
+         PCRE_INFO_FIRSTCHARACTERFLAGS
+
+       Return information about the first data unit of any matched string, for
+       a  non-anchored  pattern.  The  fourth  argument should point to an int
+       variable.
+
+       If there is a fixed first value, for example, the  letter  "c"  from  a
+       pattern  such  as  (cat|cow|coyote),  1  is returned, and the character
+       value can be retrieved using PCRE_INFO_FIRSTCHARACTER. If there  is  no
+       fixed first value, and if either
+
+       (a)  the pattern was compiled with the PCRE_MULTILINE option, and every
+       branch starts with "^", or
+
+       (b) every branch of the pattern starts with ".*" and PCRE_DOTALL is not
+       set (if it were set, the pattern would be anchored),
+
+       2 is returned, indicating that the pattern matches only at the start of
+       a subject string or after any newline within the string. Otherwise 0 is
+       returned. For anchored patterns, 0 is returned.
+
+         PCRE_INFO_FIRSTTABLE
+
+       If  the pattern was studied, and this resulted in the construction of a
+       256-bit table indicating a fixed set of values for the first data  unit
+       in  any  matching string, a pointer to the table is returned. Otherwise
+       NULL is returned. The fourth argument should point to an unsigned  char
+       * variable.
+
+         PCRE_INFO_HASCRORLF
+
+       Return  1  if  the  pattern  contains any explicit matches for CR or LF
+       characters, otherwise 0. The fourth argument should  point  to  an  int
+       variable.  An explicit match is either a literal CR or LF character, or
+       \r or \n.
+
+         PCRE_INFO_JCHANGED
+
+       Return 1 if the (?J) or (?-J) option setting is used  in  the  pattern,
+       otherwise  0. The fourth argument should point to an int variable. (?J)
+       and (?-J) set and unset the local PCRE_DUPNAMES option, respectively.
+
+         PCRE_INFO_JIT
+
+       Return 1 if the pattern was studied with one of the  JIT  options,  and
+       just-in-time compiling was successful. The fourth argument should point
+       to an int variable. A return value of 0 means that JIT support  is  not
+       available  in this version of PCRE, or that the pattern was not studied
+       with a JIT option, or that the JIT compiler could not handle this  par-
+       ticular  pattern. See the pcrejit documentation for details of what can
+       and cannot be handled.
+
+         PCRE_INFO_JITSIZE
+
+       If the pattern was successfully studied with a JIT option,  return  the
+       size  of the JIT compiled code, otherwise return zero. The fourth argu-
+       ment should point to a size_t variable.
+
+         PCRE_INFO_LASTLITERAL
+
+       Return the value of the rightmost literal data unit that must exist  in
+       any  matched  string, other than at its start, if such a value has been
+       recorded. The fourth argument should point to an int variable. If there
+       is no such value, -1 is returned. For anchored patterns, a last literal
+       value is recorded only if it follows something of variable length.  For
+       example, for the pattern /^a\d+z\d+/ the returned value is "z", but for
+       /^a\dz\d/ the returned value is -1.
+
+       Since for the 32-bit library using the non-UTF-32 mode,  this  function
+       is  unable to return the full 32-bit range of characters, this value is
+       deprecated;     instead     the     PCRE_INFO_REQUIREDCHARFLAGS     and
+       PCRE_INFO_REQUIREDCHAR values should be used.
+
+         PCRE_INFO_MATCH_EMPTY
+
+       Return  1  if  the  pattern can match an empty string, otherwise 0. The
+       fourth argument should point to an int variable.
+
+         PCRE_INFO_MATCHLIMIT
+
+       If the pattern set a match limit by  including  an  item  of  the  form
+       (*LIMIT_MATCH=nnnn)  at  the  start,  the value is returned. The fourth
+       argument should point to an unsigned 32-bit integer. If no  such  value
+       has   been   set,   the  call  to  pcre_fullinfo()  returns  the  error
+       PCRE_ERROR_UNSET.
+
+         PCRE_INFO_MAXLOOKBEHIND
+
+       Return the number of characters (NB not  data  units)  in  the  longest
+       lookbehind  assertion  in  the pattern. This information is useful when
+       doing multi-segment matching using  the  partial  matching  facilities.
+       Note that the simple assertions \b and \B require a one-character look-
+       behind. \A also registers a one-character lookbehind,  though  it  does
+       not  actually inspect the previous character. This is to ensure that at
+       least one character from the old segment is retained when a new segment
+       is processed. Otherwise, if there are no lookbehinds in the pattern, \A
+       might match incorrectly at the start of a new segment.
+
+         PCRE_INFO_MINLENGTH
+
+       If the pattern was studied and a minimum length  for  matching  subject
+       strings  was  computed,  its  value is returned. Otherwise the returned
+       value is -1. The value is a number of characters, which in UTF mode may
+       be  different from the number of data units. The fourth argument should
+       point to an int variable. A non-negative value is a lower bound to  the
+       length  of  any  matching  string. There may not be any strings of that
+       length that do actually match, but every string that does match  is  at
+       least that long.
+
+         PCRE_INFO_NAMECOUNT
+         PCRE_INFO_NAMEENTRYSIZE
+         PCRE_INFO_NAMETABLE
+
+       PCRE  supports the use of named as well as numbered capturing parenthe-
+       ses. The names are just an additional way of identifying the  parenthe-
+       ses, which still acquire numbers. Several convenience functions such as
+       pcre_get_named_substring() are provided for  extracting  captured  sub-
+       strings  by  name. It is also possible to extract the data directly, by
+       first converting the name to a number in order to  access  the  correct
+       pointers in the output vector (described with pcre_exec() below). To do
+       the conversion, you need  to  use  the  name-to-number  map,  which  is
+       described by these three values.
+
+       The map consists of a number of fixed-size entries. PCRE_INFO_NAMECOUNT
+       gives the number of entries, and PCRE_INFO_NAMEENTRYSIZE gives the size
+       of  each  entry;  both  of  these  return  an int value. The entry size
+       depends on the length of the longest name. PCRE_INFO_NAMETABLE  returns
+       a pointer to the first entry of the table. This is a pointer to char in
+       the 8-bit library, where the first two bytes of each entry are the num-
+       ber  of  the capturing parenthesis, most significant byte first. In the
+       16-bit library, the pointer points to 16-bit data units, the  first  of
+       which  contains  the  parenthesis  number.  In  the 32-bit library, the
+       pointer points to 32-bit data units, the first of  which  contains  the
+       parenthesis  number.  The  rest of the entry is the corresponding name,
+       zero terminated.
+
+       The names are in alphabetical order. If (?| is used to create  multiple
+       groups  with  the same number, as described in the section on duplicate
+       subpattern numbers in the pcrepattern page, the groups may be given the
+       same  name,  but  there is only one entry in the table. Different names
+       for groups of the same number are not permitted.  Duplicate  names  for
+       subpatterns with different numbers are permitted, but only if PCRE_DUP-
+       NAMES is set. They appear in the table in the order in which they  were
+       found  in  the  pattern.  In  the  absence  of (?| this is the order of
+       increasing number; when (?| is used this is not  necessarily  the  case
+       because later subpatterns may have lower numbers.
+
+       As  a  simple  example of the name/number table, consider the following
+       pattern after compilation by the 8-bit library (assume PCRE_EXTENDED is
+       set, so white space - including newlines - is ignored):
+
+         (?<date> (?<year>(\d\d)?\d\d) -
+         (?<month>\d\d) - (?<day>\d\d) )
+
+       There  are  four  named subpatterns, so the table has four entries, and
+       each entry in the table is eight bytes long. The table is  as  follows,
+       with non-printing bytes shows in hexadecimal, and undefined bytes shown
+       as ??:
+
+         00 01 d  a  t  e  00 ??
+         00 05 d  a  y  00 ?? ??
+         00 04 m  o  n  t  h  00
+         00 02 y  e  a  r  00 ??
+
+       When writing code to extract data  from  named  subpatterns  using  the
+       name-to-number  map,  remember that the length of the entries is likely
+       to be different for each compiled pattern.
+
+         PCRE_INFO_OKPARTIAL
+
+       Return 1  if  the  pattern  can  be  used  for  partial  matching  with
+       pcre_exec(),  otherwise  0.  The fourth argument should point to an int
+       variable. From  release  8.00,  this  always  returns  1,  because  the
+       restrictions  that  previously  applied  to  partial matching have been
+       lifted. The pcrepartial documentation gives details of  partial  match-
+       ing.
+
+         PCRE_INFO_OPTIONS
+
+       Return  a  copy of the options with which the pattern was compiled. The
+       fourth argument should point to an unsigned long  int  variable.  These
+       option bits are those specified in the call to pcre_compile(), modified
+       by any top-level option settings at the start of the pattern itself. In
+       other  words,  they are the options that will be in force when matching
+       starts. For example, if the pattern /(?im)abc(?-i)d/ is  compiled  with
+       the  PCRE_EXTENDED option, the result is PCRE_CASELESS, PCRE_MULTILINE,
+       and PCRE_EXTENDED.
+
+       A pattern is automatically anchored by PCRE if  all  of  its  top-level
+       alternatives begin with one of the following:
+
+         ^     unless PCRE_MULTILINE is set
+         \A    always
+         \G    always
+         .*    if PCRE_DOTALL is set and there are no back
+                 references to the subpattern in which .* appears
+
+       For such patterns, the PCRE_ANCHORED bit is set in the options returned
+       by pcre_fullinfo().
+
+         PCRE_INFO_RECURSIONLIMIT
+
+       If the pattern set a recursion limit by including an item of  the  form
+       (*LIMIT_RECURSION=nnnn) at the start, the value is returned. The fourth
+       argument should point to an unsigned 32-bit integer. If no  such  value
+       has   been   set,   the  call  to  pcre_fullinfo()  returns  the  error
+       PCRE_ERROR_UNSET.
+
+         PCRE_INFO_SIZE
+
+       Return the size of  the  compiled  pattern  in  bytes  (for  all  three
+       libraries). The fourth argument should point to a size_t variable. This
+       value does not include the size of the pcre structure that is  returned
+       by  pcre_compile().  The  value  that  is  passed  as  the  argument to
+       pcre_malloc() when pcre_compile() is getting memory in which  to  place
+       the compiled data is the value returned by this option plus the size of
+       the pcre structure. Studying a compiled pattern, with or  without  JIT,
+       does not alter the value returned by this option.
+
+         PCRE_INFO_STUDYSIZE
+
+       Return  the  size  in bytes (for all three libraries) of the data block
+       pointed to by the study_data field in a pcre_extra block. If pcre_extra
+       is  NULL, or there is no study data, zero is returned. The fourth argu-
+       ment should point to a size_t variable. The study_data field is set  by
+       pcre_study() to record information that will speed up matching (see the
+       section entitled  "Studying  a  pattern"  above).  The  format  of  the
+       study_data  block is private, but its length is made available via this
+       option so that it can be saved and  restored  (see  the  pcreprecompile
+       documentation for details).
+
+         PCRE_INFO_REQUIREDCHARFLAGS
+
+       Returns  1 if there is a rightmost literal data unit that must exist in
+       any matched string, other than at its start. The fourth argument should
+       point  to an int variable. If there is no such value, 0 is returned. If
+       returning  1,  the  character  value  itself  can  be  retrieved  using
+       PCRE_INFO_REQUIREDCHAR.
+
+       For anchored patterns, a last literal value is recorded only if it fol-
+       lows something  of  variable  length.  For  example,  for  the  pattern
+       /^a\d+z\d+/   the   returned   value   1   (with   "z"   returned  from
+       PCRE_INFO_REQUIREDCHAR), but for /^a\dz\d/ the returned value is 0.
+
+         PCRE_INFO_REQUIREDCHAR
+
+       Return the value of the rightmost literal data unit that must exist  in
+       any  matched  string, other than at its start, if such a value has been
+       recorded. The fourth argument should point to an uint32_t variable.  If
+       there is no such value, 0 is returned.
+
+
+REFERENCE COUNTS
+
+       int pcre_refcount(pcre *code, int adjust);
+
+       The  pcre_refcount()  function is used to maintain a reference count in
+       the data block that contains a compiled pattern. It is provided for the
+       benefit  of  applications  that  operate  in an object-oriented manner,
+       where different parts of the application may be using the same compiled
+       pattern, but you want to free the block when they are all done.
+
+       When a pattern is compiled, the reference count field is initialized to
+       zero.  It is changed only by calling this function, whose action is  to
+       add  the  adjust  value  (which may be positive or negative) to it. The
+       yield of the function is the new value. However, the value of the count
+       is  constrained to lie between 0 and 65535, inclusive. If the new value
+       is outside these limits, it is forced to the appropriate limit value.
+
+       Except when it is zero, the reference count is not correctly  preserved
+       if  a  pattern  is  compiled on one host and then transferred to a host
+       whose byte-order is different. (This seems a highly unlikely scenario.)
+
+
+MATCHING A PATTERN: THE TRADITIONAL FUNCTION
+
+       int pcre_exec(const pcre *code, const pcre_extra *extra,
+            const char *subject, int length, int startoffset,
+            int options, int *ovector, int ovecsize);
+
+       The function pcre_exec() is called to match a subject string against  a
+       compiled  pattern, which is passed in the code argument. If the pattern
+       was studied, the result of the study should  be  passed  in  the  extra
+       argument.  You  can call pcre_exec() with the same code and extra argu-
+       ments as many times as you like, in order to  match  different  subject
+       strings with the same pattern.
+
+       This  function  is  the  main  matching facility of the library, and it
+       operates in a Perl-like manner. For specialist use  there  is  also  an
+       alternative  matching function, which is described below in the section
+       about the pcre_dfa_exec() function.
+
+       In most applications, the pattern will have been compiled (and  option-
+       ally  studied)  in the same process that calls pcre_exec(). However, it
+       is possible to save compiled patterns and study data, and then use them
+       later  in  different processes, possibly even on different hosts. For a
+       discussion about this, see the pcreprecompile documentation.
+
+       Here is an example of a simple call to pcre_exec():
+
+         int rc;
+         int ovector[30];
+         rc = pcre_exec(
+           re,             /* result of pcre_compile() */
+           NULL,           /* we didn't study the pattern */
+           "some string",  /* the subject string */
+           11,             /* the length of the subject string */
+           0,              /* start at offset 0 in the subject */
+           0,              /* default options */
+           ovector,        /* vector of integers for substring information */
+           30);            /* number of elements (NOT size in bytes) */
+
+   Extra data for pcre_exec()
+
+       If the extra argument is not NULL, it must point to a  pcre_extra  data
+       block.  The pcre_study() function returns such a block (when it doesn't
+       return NULL), but you can also create one for yourself, and pass  addi-
+       tional  information  in it. The pcre_extra block contains the following
+       fields (not necessarily in this order):
+
+         unsigned long int flags;
+         void *study_data;
+         void *executable_jit;
+         unsigned long int match_limit;
+         unsigned long int match_limit_recursion;
+         void *callout_data;
+         const unsigned char *tables;
+         unsigned char **mark;
+
+       In the 16-bit version of  this  structure,  the  mark  field  has  type
+       "PCRE_UCHAR16 **".
+
+       In  the  32-bit  version  of  this  structure,  the mark field has type
+       "PCRE_UCHAR32 **".
+
+       The flags field is used to specify which of the other fields  are  set.
+       The flag bits are:
+
+         PCRE_EXTRA_CALLOUT_DATA
+         PCRE_EXTRA_EXECUTABLE_JIT
+         PCRE_EXTRA_MARK
+         PCRE_EXTRA_MATCH_LIMIT
+         PCRE_EXTRA_MATCH_LIMIT_RECURSION
+         PCRE_EXTRA_STUDY_DATA
+         PCRE_EXTRA_TABLES
+
+       Other  flag  bits should be set to zero. The study_data field and some-
+       times the executable_jit field are set in the pcre_extra block that  is
+       returned  by pcre_study(), together with the appropriate flag bits. You
+       should not set these yourself, but you may add to the block by  setting
+       other fields and their corresponding flag bits.
+
+       The match_limit field provides a means of preventing PCRE from using up
+       a vast amount of resources when running patterns that are not going  to
+       match,  but  which  have  a very large number of possibilities in their
+       search trees. The classic example is a pattern that uses nested  unlim-
+       ited repeats.
+
+       Internally,  pcre_exec() uses a function called match(), which it calls
+       repeatedly (sometimes recursively). The limit  set  by  match_limit  is
+       imposed  on the number of times this function is called during a match,
+       which has the effect of limiting the amount of  backtracking  that  can
+       take place. For patterns that are not anchored, the count restarts from
+       zero for each position in the subject string.
+
+       When pcre_exec() is called with a pattern that was successfully studied
+       with  a  JIT  option, the way that the matching is executed is entirely
+       different.  However, there is still the possibility of runaway matching
+       that goes on for a very long time, and so the match_limit value is also
+       used in this case (but in a different way) to limit how long the match-
+       ing can continue.
+
+       The  default  value  for  the  limit can be set when PCRE is built; the
+       default default is 10 million, which handles all but the  most  extreme
+       cases.  You  can  override  the  default by suppling pcre_exec() with a
+       pcre_extra    block    in    which    match_limit    is    set,     and
+       PCRE_EXTRA_MATCH_LIMIT  is  set  in  the  flags  field. If the limit is
+       exceeded, pcre_exec() returns PCRE_ERROR_MATCHLIMIT.
+
+       A value for the match limit may also be supplied  by  an  item  at  the
+       start of a pattern of the form
+
+         (*LIMIT_MATCH=d)
+
+       where  d is a decimal number. However, such a setting is ignored unless
+       d is less than the limit set by the caller of  pcre_exec()  or,  if  no
+       such limit is set, less than the default.
+
+       The  match_limit_recursion field is similar to match_limit, but instead
+       of limiting the total number of times that match() is called, it limits
+       the  depth  of  recursion. The recursion depth is a smaller number than
+       the total number of calls, because not all calls to match() are  recur-
+       sive.  This limit is of use only if it is set smaller than match_limit.
+
+       Limiting  the  recursion  depth limits the amount of machine stack that
+       can be used, or, when PCRE has been compiled to use memory on the  heap
+       instead  of the stack, the amount of heap memory that can be used. This
+       limit is not relevant, and is ignored, when matching is done using  JIT
+       compiled code.
+
+       The  default  value  for  match_limit_recursion can be set when PCRE is
+       built; the default default  is  the  same  value  as  the  default  for
+       match_limit.  You can override the default by suppling pcre_exec() with
+       a  pcre_extra  block  in  which  match_limit_recursion  is   set,   and
+       PCRE_EXTRA_MATCH_LIMIT_RECURSION  is  set  in  the  flags field. If the
+       limit is exceeded, pcre_exec() returns PCRE_ERROR_RECURSIONLIMIT.
+
+       A value for the recursion limit may also be supplied by an item at  the
+       start of a pattern of the form
+
+         (*LIMIT_RECURSION=d)
+
+       where  d is a decimal number. However, such a setting is ignored unless
+       d is less than the limit set by the caller of  pcre_exec()  or,  if  no
+       such limit is set, less than the default.
+
+       The  callout_data  field is used in conjunction with the "callout" fea-
+       ture, and is described in the pcrecallout documentation.
+
+       The tables field is provided for use with patterns that have been  pre-
+       compiled using custom character tables, saved to disc or elsewhere, and
+       then reloaded, because the tables that were used to compile  a  pattern
+       are  not saved with it. See the pcreprecompile documentation for a dis-
+       cussion of saving compiled patterns for later use. If  NULL  is  passed
+       using this mechanism, it forces PCRE's internal tables to be used.
+
+       Warning:  The  tables  that  pcre_exec() uses must be the same as those
+       that were used when the pattern was compiled. If this is not the  case,
+       the behaviour of pcre_exec() is undefined. Therefore, when a pattern is
+       compiled and matched in the same process, this field  should  never  be
+       set. In this (the most common) case, the correct table pointer is auto-
+       matically passed with  the  compiled  pattern  from  pcre_compile()  to
+       pcre_exec().
+
+       If  PCRE_EXTRA_MARK  is  set in the flags field, the mark field must be
+       set to point to a suitable variable. If the pattern contains any  back-
+       tracking  control verbs such as (*MARK:NAME), and the execution ends up
+       with a name to pass back, a pointer to the  name  string  (zero  termi-
+       nated)  is  placed  in  the  variable pointed to by the mark field. The
+       names are within the compiled pattern; if you wish  to  retain  such  a
+       name  you must copy it before freeing the memory of a compiled pattern.
+       If there is no name to pass back, the variable pointed to by  the  mark
+       field  is  set  to NULL. For details of the backtracking control verbs,
+       see the section entitled "Backtracking control" in the pcrepattern doc-
+       umentation.
+
+   Option bits for pcre_exec()
+
+       The  unused  bits of the options argument for pcre_exec() must be zero.
+       The only bits that may  be  set  are  PCRE_ANCHORED,  PCRE_NEWLINE_xxx,
+       PCRE_NOTBOL,    PCRE_NOTEOL,    PCRE_NOTEMPTY,   PCRE_NOTEMPTY_ATSTART,
+       PCRE_NO_START_OPTIMIZE,  PCRE_NO_UTF8_CHECK,   PCRE_PARTIAL_HARD,   and
+       PCRE_PARTIAL_SOFT.
+
+       If  the  pattern  was successfully studied with one of the just-in-time
+       (JIT) compile options, the only supported options for JIT execution are
+       PCRE_NO_UTF8_CHECK,     PCRE_NOTBOL,     PCRE_NOTEOL,    PCRE_NOTEMPTY,
+       PCRE_NOTEMPTY_ATSTART, PCRE_PARTIAL_HARD, and PCRE_PARTIAL_SOFT. If  an
+       unsupported  option  is  used, JIT execution is disabled and the normal
+       interpretive code in pcre_exec() is run.
+
+         PCRE_ANCHORED
+
+       The PCRE_ANCHORED option limits pcre_exec() to matching  at  the  first
+       matching  position.  If  a  pattern was compiled with PCRE_ANCHORED, or
+       turned out to be anchored by virtue of its contents, it cannot be  made
+       unachored at matching time.
+
+         PCRE_BSR_ANYCRLF
+         PCRE_BSR_UNICODE
+
+       These options (which are mutually exclusive) control what the \R escape
+       sequence matches. The choice is either to match only CR, LF,  or  CRLF,
+       or  to  match  any Unicode newline sequence. These options override the
+       choice that was made or defaulted when the pattern was compiled.
+
+         PCRE_NEWLINE_CR
+         PCRE_NEWLINE_LF
+         PCRE_NEWLINE_CRLF
+         PCRE_NEWLINE_ANYCRLF
+         PCRE_NEWLINE_ANY
+
+       These options override  the  newline  definition  that  was  chosen  or
+       defaulted  when the pattern was compiled. For details, see the descrip-
+       tion of pcre_compile()  above.  During  matching,  the  newline  choice
+       affects  the  behaviour  of the dot, circumflex, and dollar metacharac-
+       ters. It may also alter the way the match position is advanced after  a
+       match failure for an unanchored pattern.
+
+       When  PCRE_NEWLINE_CRLF,  PCRE_NEWLINE_ANYCRLF,  or PCRE_NEWLINE_ANY is
+       set, and a match attempt for an unanchored pattern fails when the  cur-
+       rent  position  is  at  a  CRLF  sequence,  and the pattern contains no
+       explicit matches for  CR  or  LF  characters,  the  match  position  is
+       advanced by two characters instead of one, in other words, to after the
+       CRLF.
+
+       The above rule is a compromise that makes the most common cases work as
+       expected.  For  example,  if  the  pattern  is .+A (and the PCRE_DOTALL
+       option is not set), it does not match the string "\r\nA" because, after
+       failing  at the start, it skips both the CR and the LF before retrying.
+       However, the pattern [\r\n]A does match that string,  because  it  con-
+       tains an explicit CR or LF reference, and so advances only by one char-
+       acter after the first failure.
+
+       An explicit match for CR of LF is either a literal appearance of one of
+       those  characters,  or  one  of the \r or \n escape sequences. Implicit
+       matches such as [^X] do not count, nor does \s (which includes  CR  and
+       LF in the characters that it matches).
+
+       Notwithstanding  the above, anomalous effects may still occur when CRLF
+       is a valid newline sequence and explicit \r or \n escapes appear in the
+       pattern.
+
+         PCRE_NOTBOL
+
+       This option specifies that first character of the subject string is not
+       the beginning of a line, so the  circumflex  metacharacter  should  not
+       match  before it. Setting this without PCRE_MULTILINE (at compile time)
+       causes circumflex never to match. This option affects only  the  behav-
+       iour of the circumflex metacharacter. It does not affect \A.
+
+         PCRE_NOTEOL
+
+       This option specifies that the end of the subject string is not the end
+       of a line, so the dollar metacharacter should not match it nor  (except
+       in  multiline mode) a newline immediately before it. Setting this with-
+       out PCRE_MULTILINE (at compile time) causes dollar never to match. This
+       option  affects only the behaviour of the dollar metacharacter. It does
+       not affect \Z or \z.
+
+         PCRE_NOTEMPTY
+
+       An empty string is not considered to be a valid match if this option is
+       set.  If  there are alternatives in the pattern, they are tried. If all
+       the alternatives match the empty string, the entire  match  fails.  For
+       example, if the pattern
+
+         a?b?
+
+       is  applied  to  a  string not beginning with "a" or "b", it matches an
+       empty string at the start of the subject. With PCRE_NOTEMPTY set,  this
+       match is not valid, so PCRE searches further into the string for occur-
+       rences of "a" or "b".
+
+         PCRE_NOTEMPTY_ATSTART
+
+       This is like PCRE_NOTEMPTY, except that an empty string match  that  is
+       not  at  the  start  of  the  subject  is  permitted. If the pattern is
+       anchored, such a match can occur only if the pattern contains \K.
+
+       Perl    has    no    direct    equivalent    of    PCRE_NOTEMPTY     or
+       PCRE_NOTEMPTY_ATSTART,  but  it  does  make a special case of a pattern
+       match of the empty string within its split() function, and  when  using
+       the  /g  modifier.  It  is  possible  to emulate Perl's behaviour after
+       matching a null string by first trying the match again at the same off-
+       set  with  PCRE_NOTEMPTY_ATSTART  and  PCRE_ANCHORED,  and then if that
+       fails, by advancing the starting offset (see below) and trying an ordi-
+       nary  match  again. There is some code that demonstrates how to do this
+       in the pcredemo sample program. In the most general case, you  have  to
+       check  to  see  if the newline convention recognizes CRLF as a newline,
+       and if so, and the current character is CR followed by LF, advance  the
+       starting offset by two characters instead of one.
+
+         PCRE_NO_START_OPTIMIZE
+
+       There  are a number of optimizations that pcre_exec() uses at the start
+       of a match, in order to speed up the process. For  example,  if  it  is
+       known that an unanchored match must start with a specific character, it
+       searches the subject for that character, and fails  immediately  if  it
+       cannot  find  it,  without actually running the main matching function.
+       This means that a special item such as (*COMMIT) at the start of a pat-
+       tern  is  not  considered until after a suitable starting point for the
+       match has been found. Also, when callouts or (*MARK) items are in  use,
+       these "start-up" optimizations can cause them to be skipped if the pat-
+       tern is never actually used. The start-up optimizations are in effect a
+       pre-scan of the subject that takes place before the pattern is run.
+
+       The  PCRE_NO_START_OPTIMIZE option disables the start-up optimizations,
+       possibly causing performance to suffer,  but  ensuring  that  in  cases
+       where  the  result is "no match", the callouts do occur, and that items
+       such as (*COMMIT) and (*MARK) are considered at every possible starting
+       position  in  the  subject  string. If PCRE_NO_START_OPTIMIZE is set at
+       compile time,  it  cannot  be  unset  at  matching  time.  The  use  of
+       PCRE_NO_START_OPTIMIZE  at  matching  time  (that  is,  passing  it  to
+       pcre_exec()) disables JIT execution; in  this  situation,  matching  is
+       always done using interpretively.
+
+       Setting  PCRE_NO_START_OPTIMIZE  can  change  the outcome of a matching
+       operation.  Consider the pattern
+
+         (*COMMIT)ABC
+
+       When this is compiled, PCRE records the fact that a  match  must  start
+       with  the  character  "A".  Suppose the subject string is "DEFABC". The
+       start-up optimization scans along the subject, finds "A" and  runs  the
+       first  match attempt from there. The (*COMMIT) item means that the pat-
+       tern must match the current starting position, which in this  case,  it
+       does.  However,  if  the  same match is run with PCRE_NO_START_OPTIMIZE
+       set, the initial scan along the subject string  does  not  happen.  The
+       first  match  attempt  is  run  starting  from "D" and when this fails,
+       (*COMMIT) prevents any further matches  being  tried,  so  the  overall
+       result  is  "no  match". If the pattern is studied, more start-up opti-
+       mizations may be used. For example, a minimum length  for  the  subject
+       may be recorded. Consider the pattern
+
+         (*MARK:A)(X|Y)
+
+       The  minimum  length  for  a  match is one character. If the subject is
+       "ABC", there will be attempts to  match  "ABC",  "BC",  "C",  and  then
+       finally  an empty string.  If the pattern is studied, the final attempt
+       does not take place, because PCRE knows that the subject is too  short,
+       and  so  the  (*MARK) is never encountered.  In this case, studying the
+       pattern does not affect the overall match result, which  is  still  "no
+       match", but it does affect the auxiliary information that is returned.
+
+         PCRE_NO_UTF8_CHECK
+
+       When PCRE_UTF8 is set at compile time, the validity of the subject as a
+       UTF-8 string is automatically checked when pcre_exec() is  subsequently
+       called.  The entire string is checked before any other processing takes
+       place. The value of startoffset is  also  checked  to  ensure  that  it
+       points  to  the start of a UTF-8 character. There is a discussion about
+       the validity of UTF-8 strings in the pcreunicode page.  If  an  invalid
+       sequence   of   bytes   is   found,   pcre_exec()   returns  the  error
+       PCRE_ERROR_BADUTF8 or, if PCRE_PARTIAL_HARD is set and the problem is a
+       truncated character at the end of the subject, PCRE_ERROR_SHORTUTF8. In
+       both cases, information about the precise nature of the error may  also
+       be  returned (see the descriptions of these errors in the section enti-
+       tled Error return values from pcre_exec() below).  If startoffset  con-
+       tains a value that does not point to the start of a UTF-8 character (or
+       to the end of the subject), PCRE_ERROR_BADUTF8_OFFSET is returned.
+
+       If you already know that your subject is valid, and you  want  to  skip
+       these    checks    for   performance   reasons,   you   can   set   the
+       PCRE_NO_UTF8_CHECK option when calling pcre_exec(). You might  want  to
+       do  this  for the second and subsequent calls to pcre_exec() if you are
+       making repeated calls to find all  the  matches  in  a  single  subject
+       string.  However,  you  should  be  sure  that the value of startoffset
+       points to the start of a character (or the end of  the  subject).  When
+       PCRE_NO_UTF8_CHECK is set, the effect of passing an invalid string as a
+       subject or an invalid value of startoffset is undefined.  Your  program
+       may crash or loop.
+
+         PCRE_PARTIAL_HARD
+         PCRE_PARTIAL_SOFT
+
+       These  options turn on the partial matching feature. For backwards com-
+       patibility, PCRE_PARTIAL is a synonym for PCRE_PARTIAL_SOFT. A  partial
+       match  occurs if the end of the subject string is reached successfully,
+       but there are not enough subject characters to complete the  match.  If
+       this happens when PCRE_PARTIAL_SOFT (but not PCRE_PARTIAL_HARD) is set,
+       matching continues by testing any remaining alternatives.  Only  if  no
+       complete  match  can be found is PCRE_ERROR_PARTIAL returned instead of
+       PCRE_ERROR_NOMATCH. In other words,  PCRE_PARTIAL_SOFT  says  that  the
+       caller  is  prepared to handle a partial match, but only if no complete
+       match can be found.
+
+       If PCRE_PARTIAL_HARD is set, it overrides  PCRE_PARTIAL_SOFT.  In  this
+       case,  if  a  partial  match  is found, pcre_exec() immediately returns
+       PCRE_ERROR_PARTIAL, without  considering  any  other  alternatives.  In
+       other  words, when PCRE_PARTIAL_HARD is set, a partial match is consid-
+       ered to be more important that an alternative complete match.
+
+       In both cases, the portion of the string that was  inspected  when  the
+       partial match was found is set as the first matching string. There is a
+       more detailed discussion of partial and  multi-segment  matching,  with
+       examples, in the pcrepartial documentation.
+
+   The string to be matched by pcre_exec()
+
+       The  subject string is passed to pcre_exec() as a pointer in subject, a
+       length in length, and a starting offset in startoffset. The  units  for
+       length  and  startoffset  are  bytes for the 8-bit library, 16-bit data
+       items for the 16-bit library, and 32-bit  data  items  for  the  32-bit
+       library.
+
+       If  startoffset  is negative or greater than the length of the subject,
+       pcre_exec() returns PCRE_ERROR_BADOFFSET. When the starting  offset  is
+       zero,  the  search  for a match starts at the beginning of the subject,
+       and this is by far the most common case. In UTF-8 or UTF-16  mode,  the
+       offset  must  point to the start of a character, or the end of the sub-
+       ject (in UTF-32 mode, one data unit equals one character, so  all  off-
+       sets  are  valid).  Unlike  the pattern string, the subject may contain
+       binary zeroes.
+
+       A non-zero starting offset is useful when searching for  another  match
+       in  the same subject by calling pcre_exec() again after a previous suc-
+       cess.  Setting startoffset differs from just passing over  a  shortened
+       string  and  setting  PCRE_NOTBOL  in the case of a pattern that begins
+       with any kind of lookbehind. For example, consider the pattern
+
+         \Biss\B
+
+       which finds occurrences of "iss" in the middle of  words.  (\B  matches
+       only  if  the  current position in the subject is not a word boundary.)
+       When applied to the string "Mississipi" the first call  to  pcre_exec()
+       finds  the  first  occurrence. If pcre_exec() is called again with just
+       the remainder of the subject,  namely  "issipi",  it  does  not  match,
+       because \B is always false at the start of the subject, which is deemed
+       to be a word boundary. However, if pcre_exec()  is  passed  the  entire
+       string again, but with startoffset set to 4, it finds the second occur-
+       rence of "iss" because it is able to look behind the starting point  to
+       discover that it is preceded by a letter.
+
+       Finding  all  the  matches  in a subject is tricky when the pattern can
+       match an empty string. It is possible to emulate Perl's /g behaviour by
+       first   trying   the   match   again  at  the  same  offset,  with  the
+       PCRE_NOTEMPTY_ATSTART and  PCRE_ANCHORED  options,  and  then  if  that
+       fails,  advancing  the  starting  offset  and  trying an ordinary match
+       again. There is some code that demonstrates how to do this in the pcre-
+       demo sample program. In the most general case, you have to check to see
+       if the newline convention recognizes CRLF as a newline, and if so,  and
+       the current character is CR followed by LF, advance the starting offset
+       by two characters instead of one.
+
+       If a non-zero starting offset is passed when the pattern  is  anchored,
+       one attempt to match at the given offset is made. This can only succeed
+       if the pattern does not require the match to be at  the  start  of  the
+       subject.
+
+   How pcre_exec() returns captured substrings
+
+       In  general, a pattern matches a certain portion of the subject, and in
+       addition, further substrings from the subject  may  be  picked  out  by
+       parts  of  the  pattern.  Following the usage in Jeffrey Friedl's book,
+       this is called "capturing" in what follows, and the  phrase  "capturing
+       subpattern"  is  used for a fragment of a pattern that picks out a sub-
+       string. PCRE supports several other kinds of  parenthesized  subpattern
+       that do not cause substrings to be captured.
+
+       Captured substrings are returned to the caller via a vector of integers
+       whose address is passed in ovector. The number of elements in the  vec-
+       tor  is  passed in ovecsize, which must be a non-negative number. Note:
+       this argument is NOT the size of ovector in bytes.
+
+       The first two-thirds of the vector is used to pass back  captured  sub-
+       strings,  each  substring using a pair of integers. The remaining third
+       of the vector is used as workspace by pcre_exec() while  matching  cap-
+       turing  subpatterns, and is not available for passing back information.
+       The number passed in ovecsize should always be a multiple of three.  If
+       it is not, it is rounded down.
+
+       When  a  match  is successful, information about captured substrings is
+       returned in pairs of integers, starting at the  beginning  of  ovector,
+       and  continuing  up  to two-thirds of its length at the most. The first
+       element of each pair is set to the offset of the first character  in  a
+       substring,  and  the second is set to the offset of the first character
+       after the end of a substring. These values are always  data  unit  off-
+       sets,  even  in  UTF  mode. They are byte offsets in the 8-bit library,
+       16-bit data item offsets in the 16-bit library, and  32-bit  data  item
+       offsets in the 32-bit library. Note: they are not character counts.
+
+       The  first  pair  of  integers, ovector[0] and ovector[1], identify the
+       portion of the subject string matched by the entire pattern.  The  next
+       pair  is  used for the first capturing subpattern, and so on. The value
+       returned by pcre_exec() is one more than the highest numbered pair that
+       has  been  set.  For example, if two substrings have been captured, the
+       returned value is 3. If there are no capturing subpatterns, the  return
+       value from a successful match is 1, indicating that just the first pair
+       of offsets has been set.
+
+       If a capturing subpattern is matched repeatedly, it is the last portion
+       of the string that it matched that is returned.
+
+       If  the vector is too small to hold all the captured substring offsets,
+       it is used as far as possible (up to two-thirds of its length), and the
+       function  returns a value of zero. If neither the actual string matched
+       nor any captured substrings are of interest, pcre_exec() may be  called
+       with  ovector passed as NULL and ovecsize as zero. However, if the pat-
+       tern contains back references and the ovector  is  not  big  enough  to
+       remember  the related substrings, PCRE has to get additional memory for
+       use during matching. Thus it is usually advisable to supply an  ovector
+       of reasonable size.
+
+       There  are  some  cases where zero is returned (indicating vector over-
+       flow) when in fact the vector is exactly the right size for  the  final
+       match. For example, consider the pattern
+
+         (a)(?:(b)c|bd)
+
+       If  a  vector of 6 elements (allowing for only 1 captured substring) is
+       given with subject string "abd", pcre_exec() will try to set the second
+       captured string, thereby recording a vector overflow, before failing to
+       match "c" and backing up  to  try  the  second  alternative.  The  zero
+       return,  however,  does  correctly  indicate that the maximum number of
+       slots (namely 2) have been filled. In similar cases where there is tem-
+       porary  overflow,  but  the final number of used slots is actually less
+       than the maximum, a non-zero value is returned.
+
+       The pcre_fullinfo() function can be used to find out how many capturing
+       subpatterns  there  are  in  a  compiled pattern. The smallest size for
+       ovector that will allow for n captured substrings, in addition  to  the
+       offsets of the substring matched by the whole pattern, is (n+1)*3.
+
+       It  is  possible for capturing subpattern number n+1 to match some part
+       of the subject when subpattern n has not been used at all. For example,
+       if  the  string  "abc"  is  matched against the pattern (a|(z))(bc) the
+       return from the function is 4, and subpatterns 1 and 3 are matched, but
+       2  is  not.  When  this happens, both values in the offset pairs corre-
+       sponding to unused subpatterns are set to -1.
+
+       Offset values that correspond to unused subpatterns at the end  of  the
+       expression  are  also  set  to  -1. For example, if the string "abc" is
+       matched against the pattern (abc)(x(yz)?)? subpatterns 2 and 3 are  not
+       matched.  The  return  from the function is 2, because the highest used
+       capturing subpattern number is 1, and the offsets for  for  the  second
+       and  third  capturing subpatterns (assuming the vector is large enough,
+       of course) are set to -1.
+
+       Note: Elements in the first two-thirds of ovector that  do  not  corre-
+       spond  to  capturing parentheses in the pattern are never changed. That
+       is, if a pattern contains n capturing parentheses, no more  than  ovec-
+       tor[0]  to ovector[2n+1] are set by pcre_exec(). The other elements (in
+       the first two-thirds) retain whatever values they previously had.
+
+       Some convenience functions are provided  for  extracting  the  captured
+       substrings as separate strings. These are described below.
+
+   Error return values from pcre_exec()
+
+       If  pcre_exec()  fails, it returns a negative number. The following are
+       defined in the header file:
+
+         PCRE_ERROR_NOMATCH        (-1)
+
+       The subject string did not match the pattern.
+
+         PCRE_ERROR_NULL           (-2)
+
+       Either code or subject was passed as NULL,  or  ovector  was  NULL  and
+       ovecsize was not zero.
+
+         PCRE_ERROR_BADOPTION      (-3)
+
+       An unrecognized bit was set in the options argument.
+
+         PCRE_ERROR_BADMAGIC       (-4)
+
+       PCRE  stores a 4-byte "magic number" at the start of the compiled code,
+       to catch the case when it is passed a junk pointer and to detect when a
+       pattern that was compiled in an environment of one endianness is run in
+       an environment with the other endianness. This is the error  that  PCRE
+       gives when the magic number is not present.
+
+         PCRE_ERROR_UNKNOWN_OPCODE (-5)
+
+       While running the pattern match, an unknown item was encountered in the
+       compiled pattern. This error could be caused by a bug  in  PCRE  or  by
+       overwriting of the compiled pattern.
+
+         PCRE_ERROR_NOMEMORY       (-6)
+
+       If  a  pattern contains back references, but the ovector that is passed
+       to pcre_exec() is not big enough to remember the referenced substrings,
+       PCRE  gets  a  block of memory at the start of matching to use for this
+       purpose. If the call via pcre_malloc() fails, this error is given.  The
+       memory is automatically freed at the end of matching.
+
+       This  error  is also given if pcre_stack_malloc() fails in pcre_exec().
+       This can happen only when PCRE has been compiled with  --disable-stack-
+       for-recursion.
+
+         PCRE_ERROR_NOSUBSTRING    (-7)
+
+       This  error is used by the pcre_copy_substring(), pcre_get_substring(),
+       and  pcre_get_substring_list()  functions  (see  below).  It  is  never
+       returned by pcre_exec().
+
+         PCRE_ERROR_MATCHLIMIT     (-8)
+
+       The  backtracking  limit,  as  specified  by the match_limit field in a
+       pcre_extra structure (or defaulted) was reached.  See  the  description
+       above.
+
+         PCRE_ERROR_CALLOUT        (-9)
+
+       This error is never generated by pcre_exec() itself. It is provided for
+       use by callout functions that want to yield a distinctive  error  code.
+       See the pcrecallout documentation for details.
+
+         PCRE_ERROR_BADUTF8        (-10)
+
+       A  string  that contains an invalid UTF-8 byte sequence was passed as a
+       subject, and the PCRE_NO_UTF8_CHECK option was not set. If the size  of
+       the  output  vector  (ovecsize)  is  at least 2, the byte offset to the
+       start of the the invalid UTF-8 character is placed in  the  first  ele-
+       ment,  and  a  reason  code is placed in the second element. The reason
+       codes are listed in the following section.  For backward compatibility,
+       if  PCRE_PARTIAL_HARD is set and the problem is a truncated UTF-8 char-
+       acter  at  the  end  of  the   subject   (reason   codes   1   to   5),
+       PCRE_ERROR_SHORTUTF8 is returned instead of PCRE_ERROR_BADUTF8.
+
+         PCRE_ERROR_BADUTF8_OFFSET (-11)
+
+       The  UTF-8  byte  sequence that was passed as a subject was checked and
+       found to be valid (the PCRE_NO_UTF8_CHECK option was not set), but  the
+       value  of startoffset did not point to the beginning of a UTF-8 charac-
+       ter or the end of the subject.
+
+         PCRE_ERROR_PARTIAL        (-12)
+
+       The subject string did not match, but it did match partially.  See  the
+       pcrepartial documentation for details of partial matching.
+
+         PCRE_ERROR_BADPARTIAL     (-13)
+
+       This  code  is  no  longer  in  use.  It was formerly returned when the
+       PCRE_PARTIAL option was used with a compiled pattern  containing  items
+       that  were  not  supported  for  partial  matching.  From  release 8.00
+       onwards, there are no restrictions on partial matching.
+
+         PCRE_ERROR_INTERNAL       (-14)
+
+       An unexpected internal error has occurred. This error could  be  caused
+       by a bug in PCRE or by overwriting of the compiled pattern.
+
+         PCRE_ERROR_BADCOUNT       (-15)
+
+       This error is given if the value of the ovecsize argument is negative.
+
+         PCRE_ERROR_RECURSIONLIMIT (-21)
+
+       The internal recursion limit, as specified by the match_limit_recursion
+       field in a pcre_extra structure (or defaulted)  was  reached.  See  the
+       description above.
+
+         PCRE_ERROR_BADNEWLINE     (-23)
+
+       An invalid combination of PCRE_NEWLINE_xxx options was given.
+
+         PCRE_ERROR_BADOFFSET      (-24)
+
+       The value of startoffset was negative or greater than the length of the
+       subject, that is, the value in length.
+
+         PCRE_ERROR_SHORTUTF8      (-25)
+
+       This error is returned instead of PCRE_ERROR_BADUTF8 when  the  subject
+       string  ends with a truncated UTF-8 character and the PCRE_PARTIAL_HARD
+       option is set.  Information  about  the  failure  is  returned  as  for
+       PCRE_ERROR_BADUTF8.  It  is in fact sufficient to detect this case, but
+       this special error code for PCRE_PARTIAL_HARD precedes the  implementa-
+       tion  of returned information; it is retained for backwards compatibil-
+       ity.
+
+         PCRE_ERROR_RECURSELOOP    (-26)
+
+       This error is returned when pcre_exec() detects a recursion loop within
+       the  pattern. Specifically, it means that either the whole pattern or a
+       subpattern has been called recursively for the second time at the  same
+       position in the subject string. Some simple patterns that might do this
+       are detected and faulted at compile time, but more  complicated  cases,
+       in particular mutual recursions between two different subpatterns, can-
+       not be detected until run time.
+
+         PCRE_ERROR_JIT_STACKLIMIT (-27)
+
+       This error is returned when a pattern  that  was  successfully  studied
+       using  a  JIT compile option is being matched, but the memory available
+       for the just-in-time processing stack is  not  large  enough.  See  the
+       pcrejit documentation for more details.
+
+         PCRE_ERROR_BADMODE        (-28)
+
+       This error is given if a pattern that was compiled by the 8-bit library
+       is passed to a 16-bit or 32-bit library function, or vice versa.
+
+         PCRE_ERROR_BADENDIANNESS  (-29)
+
+       This error is given if  a  pattern  that  was  compiled  and  saved  is
+       reloaded  on  a  host  with  different endianness. The utility function
+       pcre_pattern_to_host_byte_order() can be used to convert such a pattern
+       so that it runs on the new host.
+
+         PCRE_ERROR_JIT_BADOPTION
+
+       This  error  is  returned  when a pattern that was successfully studied
+       using a JIT compile option is being  matched,  but  the  matching  mode
+       (partial  or complete match) does not correspond to any JIT compilation
+       mode. When the JIT fast path function is used, this error may  be  also
+       given  for  invalid  options.  See  the  pcrejit documentation for more
+       details.
+
+         PCRE_ERROR_BADLENGTH      (-32)
+
+       This error is given if pcre_exec() is called with a negative value  for
+       the length argument.
+
+       Error numbers -16 to -20, -22, and 30 are not used by pcre_exec().
+
+   Reason codes for invalid UTF-8 strings
+
+       This  section  applies  only  to  the  8-bit library. The corresponding
+       information for the 16-bit and 32-bit libraries is given in the  pcre16
+       and pcre32 pages.
+
+       When pcre_exec() returns either PCRE_ERROR_BADUTF8 or PCRE_ERROR_SHORT-
+       UTF8, and the size of the output vector (ovecsize) is at least  2,  the
+       offset  of  the  start  of the invalid UTF-8 character is placed in the
+       first output vector element (ovector[0]) and a reason code is placed in
+       the  second  element  (ovector[1]). The reason codes are given names in
+       the pcre.h header file:
+
+         PCRE_UTF8_ERR1
+         PCRE_UTF8_ERR2
+         PCRE_UTF8_ERR3
+         PCRE_UTF8_ERR4
+         PCRE_UTF8_ERR5
+
+       The string ends with a truncated UTF-8 character;  the  code  specifies
+       how  many bytes are missing (1 to 5). Although RFC 3629 restricts UTF-8
+       characters to be no longer than 4 bytes, the  encoding  scheme  (origi-
+       nally  defined  by  RFC  2279)  allows  for  up to 6 bytes, and this is
+       checked first; hence the possibility of 4 or 5 missing bytes.
+
+         PCRE_UTF8_ERR6
+         PCRE_UTF8_ERR7
+         PCRE_UTF8_ERR8
+         PCRE_UTF8_ERR9
+         PCRE_UTF8_ERR10
+
+       The two most significant bits of the 2nd, 3rd, 4th, 5th, or 6th byte of
+       the  character  do  not have the binary value 0b10 (that is, either the
+       most significant bit is 0, or the next bit is 1).
+
+         PCRE_UTF8_ERR11
+         PCRE_UTF8_ERR12
+
+       A character that is valid by the RFC 2279 rules is either 5 or 6  bytes
+       long; these code points are excluded by RFC 3629.
+
+         PCRE_UTF8_ERR13
+
+       A  4-byte character has a value greater than 0x10fff; these code points
+       are excluded by RFC 3629.
+
+         PCRE_UTF8_ERR14
+
+       A 3-byte character has a value in the  range  0xd800  to  0xdfff;  this
+       range  of code points are reserved by RFC 3629 for use with UTF-16, and
+       so are excluded from UTF-8.
+
+         PCRE_UTF8_ERR15
+         PCRE_UTF8_ERR16
+         PCRE_UTF8_ERR17
+         PCRE_UTF8_ERR18
+         PCRE_UTF8_ERR19
+
+       A 2-, 3-, 4-, 5-, or 6-byte character is "overlong", that is, it  codes
+       for  a  value that can be represented by fewer bytes, which is invalid.
+       For example, the two bytes 0xc0, 0xae give the value 0x2e,  whose  cor-
+       rect coding uses just one byte.
+
+         PCRE_UTF8_ERR20
+
+       The two most significant bits of the first byte of a character have the
+       binary value 0b10 (that is, the most significant bit is 1 and the  sec-
+       ond  is  0). Such a byte can only validly occur as the second or subse-
+       quent byte of a multi-byte character.
+
+         PCRE_UTF8_ERR21
+
+       The first byte of a character has the value 0xfe or 0xff. These  values
+       can never occur in a valid UTF-8 string.
+
+         PCRE_UTF8_ERR22
+
+       This  error  code  was  formerly  used when the presence of a so-called
+       "non-character" caused an error. Unicode corrigendum #9 makes it  clear
+       that  such  characters should not cause a string to be rejected, and so
+       this code is no longer in use and is never returned.
+
+
+EXTRACTING CAPTURED SUBSTRINGS BY NUMBER
+
+       int pcre_copy_substring(const char *subject, int *ovector,
+            int stringcount, int stringnumber, char *buffer,
+            int buffersize);
+
+       int pcre_get_substring(const char *subject, int *ovector,
+            int stringcount, int stringnumber,
+            const char **stringptr);
+
+       int pcre_get_substring_list(const char *subject,
+            int *ovector, int stringcount, const char ***listptr);
+
+       Captured substrings can be  accessed  directly  by  using  the  offsets
+       returned  by  pcre_exec()  in  ovector.  For convenience, the functions
+       pcre_copy_substring(),    pcre_get_substring(),    and    pcre_get_sub-
+       string_list()  are  provided for extracting captured substrings as new,
+       separate, zero-terminated strings. These functions identify  substrings
+       by  number.  The  next section describes functions for extracting named
+       substrings.
+
+       A substring that contains a binary zero is correctly extracted and  has
+       a  further zero added on the end, but the result is not, of course, a C
+       string.  However, you can process such a string  by  referring  to  the
+       length  that  is  returned  by  pcre_copy_substring() and pcre_get_sub-
+       string().  Unfortunately, the interface to pcre_get_substring_list() is
+       not  adequate for handling strings containing binary zeros, because the
+       end of the final string is not independently indicated.
+
+       The first three arguments are the same for all  three  of  these  func-
+       tions:  subject  is  the subject string that has just been successfully
+       matched, ovector is a pointer to the vector of integer offsets that was
+       passed to pcre_exec(), and stringcount is the number of substrings that
+       were captured by the match, including the substring  that  matched  the
+       entire regular expression. This is the value returned by pcre_exec() if
+       it is greater than zero. If pcre_exec() returned zero, indicating  that
+       it  ran out of space in ovector, the value passed as stringcount should
+       be the number of elements in the vector divided by three.
+
+       The functions pcre_copy_substring() and pcre_get_substring() extract  a
+       single  substring,  whose  number  is given as stringnumber. A value of
+       zero extracts the substring that matched the  entire  pattern,  whereas
+       higher  values  extract  the  captured  substrings.  For pcre_copy_sub-
+       string(), the string is placed in buffer,  whose  length  is  given  by
+       buffersize,  while  for  pcre_get_substring()  a new block of memory is
+       obtained via pcre_malloc, and its address is  returned  via  stringptr.
+       The  yield  of  the function is the length of the string, not including
+       the terminating zero, or one of these error codes:
+
+         PCRE_ERROR_NOMEMORY       (-6)
+
+       The buffer was too small for pcre_copy_substring(), or the  attempt  to
+       get memory failed for pcre_get_substring().
+
+         PCRE_ERROR_NOSUBSTRING    (-7)
+
+       There is no substring whose number is stringnumber.
+
+       The  pcre_get_substring_list()  function  extracts  all  available sub-
+       strings and builds a list of pointers to them. All this is  done  in  a
+       single block of memory that is obtained via pcre_malloc. The address of
+       the memory block is returned via listptr, which is also  the  start  of
+       the  list  of  string pointers. The end of the list is marked by a NULL
+       pointer. The yield of the function is zero if all  went  well,  or  the
+       error code
+
+         PCRE_ERROR_NOMEMORY       (-6)
+
+       if the attempt to get the memory block failed.
+
+       When  any of these functions encounter a substring that is unset, which
+       can happen when capturing subpattern number n+1 matches  some  part  of
+       the  subject, but subpattern n has not been used at all, they return an
+       empty string. This can be distinguished from a genuine zero-length sub-
+       string  by inspecting the appropriate offset in ovector, which is nega-
+       tive for unset substrings.
+
+       The two convenience functions pcre_free_substring() and  pcre_free_sub-
+       string_list()  can  be  used  to free the memory returned by a previous
+       call  of  pcre_get_substring()  or  pcre_get_substring_list(),  respec-
+       tively.  They  do  nothing  more  than  call the function pointed to by
+       pcre_free, which of course could be called directly from a  C  program.
+       However,  PCRE is used in some situations where it is linked via a spe-
+       cial  interface  to  another  programming  language  that  cannot   use
+       pcre_free  directly;  it is for these cases that the functions are pro-
+       vided.
+
+
+EXTRACTING CAPTURED SUBSTRINGS BY NAME
+
+       int pcre_get_stringnumber(const pcre *code,
+            const char *name);
+
+       int pcre_copy_named_substring(const pcre *code,
+            const char *subject, int *ovector,
+            int stringcount, const char *stringname,
+            char *buffer, int buffersize);
+
+       int pcre_get_named_substring(const pcre *code,
+            const char *subject, int *ovector,
+            int stringcount, const char *stringname,
+            const char **stringptr);
+
+       To extract a substring by name, you first have to find associated  num-
+       ber.  For example, for this pattern
+
+         (a+)b(?<xxx>\d+)...
+
+       the number of the subpattern called "xxx" is 2. If the name is known to
+       be unique (PCRE_DUPNAMES was not set), you can find the number from the
+       name by calling pcre_get_stringnumber(). The first argument is the com-
+       piled pattern, and the second is the name. The yield of the function is
+       the  subpattern  number,  or PCRE_ERROR_NOSUBSTRING (-7) if there is no
+       subpattern of that name.
+
+       Given the number, you can extract the substring directly, or use one of
+       the functions described in the previous section. For convenience, there
+       are also two functions that do the whole job.
+
+       Most   of   the   arguments    of    pcre_copy_named_substring()    and
+       pcre_get_named_substring()  are  the  same  as  those for the similarly
+       named functions that extract by number. As these are described  in  the
+       previous  section,  they  are not re-described here. There are just two
+       differences:
+
+       First, instead of a substring number, a substring name is  given.  Sec-
+       ond, there is an extra argument, given at the start, which is a pointer
+       to the compiled pattern. This is needed in order to gain access to  the
+       name-to-number translation table.
+
+       These  functions call pcre_get_stringnumber(), and if it succeeds, they
+       then call pcre_copy_substring() or pcre_get_substring(),  as  appropri-
+       ate.  NOTE:  If PCRE_DUPNAMES is set and there are duplicate names, the
+       behaviour may not be what you want (see the next section).
+
+       Warning: If the pattern uses the (?| feature to set up multiple subpat-
+       terns  with  the  same number, as described in the section on duplicate
+       subpattern numbers in the pcrepattern page, you  cannot  use  names  to
+       distinguish  the  different subpatterns, because names are not included
+       in the compiled code. The matching process uses only numbers. For  this
+       reason,  the  use of different names for subpatterns of the same number
+       causes an error at compile time.
+
+
+DUPLICATE SUBPATTERN NAMES
+
+       int pcre_get_stringtable_entries(const pcre *code,
+            const char *name, char **first, char **last);
+
+       When a pattern is compiled with the  PCRE_DUPNAMES  option,  names  for
+       subpatterns  are not required to be unique. (Duplicate names are always
+       allowed for subpatterns with the same number, created by using the  (?|
+       feature.  Indeed,  if  such subpatterns are named, they are required to
+       use the same names.)
+
+       Normally, patterns with duplicate names are such that in any one match,
+       only  one of the named subpatterns participates. An example is shown in
+       the pcrepattern documentation.
+
+       When   duplicates   are   present,   pcre_copy_named_substring()    and
+       pcre_get_named_substring()  return the first substring corresponding to
+       the given name that is set. If  none  are  set,  PCRE_ERROR_NOSUBSTRING
+       (-7)  is  returned;  no  data  is returned. The pcre_get_stringnumber()
+       function returns one of the numbers that are associated with the  name,
+       but it is not defined which it is.
+
+       If  you want to get full details of all captured substrings for a given
+       name, you must use  the  pcre_get_stringtable_entries()  function.  The
+       first argument is the compiled pattern, and the second is the name. The
+       third and fourth are pointers to variables which  are  updated  by  the
+       function. After it has run, they point to the first and last entries in
+       the name-to-number table  for  the  given  name.  The  function  itself
+       returns  the  length  of  each entry, or PCRE_ERROR_NOSUBSTRING (-7) if
+       there are none. The format of the table is described above in the  sec-
+       tion  entitled  Information about a pattern above.  Given all the rele-
+       vant entries for the name, you can extract each of their  numbers,  and
+       hence the captured data, if any.
+
+
+FINDING ALL POSSIBLE MATCHES
+
+       The  traditional  matching  function  uses a similar algorithm to Perl,
+       which stops when it finds the first match, starting at a given point in
+       the  subject.  If you want to find all possible matches, or the longest
+       possible match, consider using the alternative matching  function  (see
+       below)  instead.  If you cannot use the alternative function, but still
+       need to find all possible matches, you can kludge it up by  making  use
+       of the callout facility, which is described in the pcrecallout documen-
+       tation.
+
+       What you have to do is to insert a callout right at the end of the pat-
+       tern.   When your callout function is called, extract and save the cur-
+       rent matched substring. Then return  1,  which  forces  pcre_exec()  to
+       backtrack  and  try other alternatives. Ultimately, when it runs out of
+       matches, pcre_exec() will yield PCRE_ERROR_NOMATCH.
+
+
+OBTAINING AN ESTIMATE OF STACK USAGE
+
+       Matching certain patterns using pcre_exec() can use a  lot  of  process
+       stack,  which  in  certain  environments can be rather limited in size.
+       Some users find it helpful to have an estimate of the amount  of  stack
+       that  is  used  by  pcre_exec(),  to help them set recursion limits, as
+       described in the pcrestack documentation. The estimate that  is  output
+       by pcretest when called with the -m and -C options is obtained by call-
+       ing pcre_exec with the values NULL, NULL, NULL, -999, and -999 for  its
+       first five arguments.
+
+       Normally,  if  its  first  argument  is  NULL,  pcre_exec() immediately
+       returns the negative error code PCRE_ERROR_NULL, but with this  special
+       combination  of  arguments,  it returns instead a negative number whose
+       absolute value is the approximate stack frame size in bytes.  (A  nega-
+       tive  number  is  used so that it is clear that no match has happened.)
+       The value is approximate because in  some  cases,  recursive  calls  to
+       pcre_exec() occur when there are one or two additional variables on the
+       stack.
+
+       If PCRE has been compiled to use the heap  instead  of  the  stack  for
+       recursion,  the  value  returned  is  the  size  of  each block that is
+       obtained from the heap.
+
+
+MATCHING A PATTERN: THE ALTERNATIVE FUNCTION
+
+       int pcre_dfa_exec(const pcre *code, const pcre_extra *extra,
+            const char *subject, int length, int startoffset,
+            int options, int *ovector, int ovecsize,
+            int *workspace, int wscount);
+
+       The function pcre_dfa_exec()  is  called  to  match  a  subject  string
+       against  a  compiled pattern, using a matching algorithm that scans the
+       subject string just once, and does not backtrack.  This  has  different
+       characteristics  to  the  normal  algorithm, and is not compatible with
+       Perl. Some of the features of PCRE patterns are not  supported.  Never-
+       theless,  there are times when this kind of matching can be useful. For
+       a discussion of the two matching algorithms, and  a  list  of  features
+       that  pcre_dfa_exec() does not support, see the pcrematching documenta-
+       tion.
+
+       The arguments for the pcre_dfa_exec() function  are  the  same  as  for
+       pcre_exec(), plus two extras. The ovector argument is used in a differ-
+       ent way, and this is described below. The other  common  arguments  are
+       used  in  the  same way as for pcre_exec(), so their description is not
+       repeated here.
+
+       The two additional arguments provide workspace for  the  function.  The
+       workspace  vector  should  contain at least 20 elements. It is used for
+       keeping  track  of  multiple  paths  through  the  pattern  tree.  More
+       workspace  will  be  needed for patterns and subjects where there are a
+       lot of potential matches.
+
+       Here is an example of a simple call to pcre_dfa_exec():
+
+         int rc;
+         int ovector[10];
+         int wspace[20];
+         rc = pcre_dfa_exec(
+           re,             /* result of pcre_compile() */
+           NULL,           /* we didn't study the pattern */
+           "some string",  /* the subject string */
+           11,             /* the length of the subject string */
+           0,              /* start at offset 0 in the subject */
+           0,              /* default options */
+           ovector,        /* vector of integers for substring information */
+           10,             /* number of elements (NOT size in bytes) */
+           wspace,         /* working space vector */
+           20);            /* number of elements (NOT size in bytes) */
+
+   Option bits for pcre_dfa_exec()
+
+       The unused bits of the options argument  for  pcre_dfa_exec()  must  be
+       zero.  The  only  bits  that  may  be  set are PCRE_ANCHORED, PCRE_NEW-
+       LINE_xxx,        PCRE_NOTBOL,        PCRE_NOTEOL,        PCRE_NOTEMPTY,
+       PCRE_NOTEMPTY_ATSTART,       PCRE_NO_UTF8_CHECK,      PCRE_BSR_ANYCRLF,
+       PCRE_BSR_UNICODE, PCRE_NO_START_OPTIMIZE, PCRE_PARTIAL_HARD,  PCRE_PAR-
+       TIAL_SOFT,  PCRE_DFA_SHORTEST,  and PCRE_DFA_RESTART.  All but the last
+       four of these are  exactly  the  same  as  for  pcre_exec(),  so  their
+       description is not repeated here.
+
+         PCRE_PARTIAL_HARD
+         PCRE_PARTIAL_SOFT
+
+       These  have the same general effect as they do for pcre_exec(), but the
+       details are slightly  different.  When  PCRE_PARTIAL_HARD  is  set  for
+       pcre_dfa_exec(),  it  returns PCRE_ERROR_PARTIAL if the end of the sub-
+       ject is reached and there is still at least  one  matching  possibility
+       that requires additional characters. This happens even if some complete
+       matches have also been found. When PCRE_PARTIAL_SOFT is set, the return
+       code PCRE_ERROR_NOMATCH is converted into PCRE_ERROR_PARTIAL if the end
+       of the subject is reached, there have been  no  complete  matches,  but
+       there  is  still  at least one matching possibility. The portion of the
+       string that was inspected when the longest partial match was  found  is
+       set  as  the  first  matching  string  in  both cases.  There is a more
+       detailed discussion of partial and multi-segment matching,  with  exam-
+       ples, in the pcrepartial documentation.
+
+         PCRE_DFA_SHORTEST
+
+       Setting  the  PCRE_DFA_SHORTEST option causes the matching algorithm to
+       stop as soon as it has found one match. Because of the way the alterna-
+       tive  algorithm  works, this is necessarily the shortest possible match
+       at the first possible matching point in the subject string.
+
+         PCRE_DFA_RESTART
+
+       When pcre_dfa_exec() returns a partial match, it is possible to call it
+       again,  with  additional  subject characters, and have it continue with
+       the same match. The PCRE_DFA_RESTART option requests this action;  when
+       it  is  set,  the workspace and wscount options must reference the same
+       vector as before because data about the match so far is  left  in  them
+       after a partial match. There is more discussion of this facility in the
+       pcrepartial documentation.
+
+   Successful returns from pcre_dfa_exec()
+
+       When pcre_dfa_exec() succeeds, it may have matched more than  one  sub-
+       string in the subject. Note, however, that all the matches from one run
+       of the function start at the same point in  the  subject.  The  shorter
+       matches  are all initial substrings of the longer matches. For example,
+       if the pattern
+
+         <.*>
+
+       is matched against the string
+
+         This is <something> <something else> <something further> no more
+
+       the three matched strings are
+
+         <something>
+         <something> <something else>
+         <something> <something else> <something further>
+
+       On success, the yield of the function is a number  greater  than  zero,
+       which  is  the  number of matched substrings. The substrings themselves
+       are returned in ovector. Each string uses two elements;  the  first  is
+       the  offset  to  the start, and the second is the offset to the end. In
+       fact, all the strings have the same start  offset.  (Space  could  have
+       been  saved by giving this only once, but it was decided to retain some
+       compatibility with the way pcre_exec() returns data,  even  though  the
+       meaning of the strings is different.)
+
+       The strings are returned in reverse order of length; that is, the long-
+       est matching string is given first. If there were too many  matches  to
+       fit  into ovector, the yield of the function is zero, and the vector is
+       filled with the longest matches.  Unlike  pcre_exec(),  pcre_dfa_exec()
+       can use the entire ovector for returning matched strings.
+
+       NOTE:  PCRE's  "auto-possessification"  optimization usually applies to
+       character repeats at the end of a pattern (as well as internally).  For
+       example,  the  pattern "a\d+" is compiled as if it were "a\d++" because
+       there is no point even considering the possibility of backtracking into
+       the  repeated digits. For DFA matching, this means that only one possi-
+       ble match is found. If you really do  want  multiple  matches  in  such
+       cases,   either   use   an   ungreedy   repeat  ("a\d+?")  or  set  the
+       PCRE_NO_AUTO_POSSESS option when compiling.
+
+   Error returns from pcre_dfa_exec()
+
+       The pcre_dfa_exec() function returns a negative number when  it  fails.
+       Many  of  the  errors  are  the  same as for pcre_exec(), and these are
+       described above.  There are in addition the following errors  that  are
+       specific to pcre_dfa_exec():
+
+         PCRE_ERROR_DFA_UITEM      (-16)
+
+       This  return is given if pcre_dfa_exec() encounters an item in the pat-
+       tern that it does not support, for instance, the use of \C  or  a  back
+       reference.
+
+         PCRE_ERROR_DFA_UCOND      (-17)
+
+       This  return  is  given  if pcre_dfa_exec() encounters a condition item
+       that uses a back reference for the condition, or a test  for  recursion
+       in a specific group. These are not supported.
+
+         PCRE_ERROR_DFA_UMLIMIT    (-18)
+
+       This  return  is given if pcre_dfa_exec() is called with an extra block
+       that contains a setting of  the  match_limit  or  match_limit_recursion
+       fields.  This  is  not  supported (these fields are meaningless for DFA
+       matching).
+
+         PCRE_ERROR_DFA_WSSIZE     (-19)
+
+       This return is given if  pcre_dfa_exec()  runs  out  of  space  in  the
+       workspace vector.
+
+         PCRE_ERROR_DFA_RECURSE    (-20)
+
+       When  a  recursive subpattern is processed, the matching function calls
+       itself recursively, using private vectors for  ovector  and  workspace.
+       This  error  is  given  if  the output vector is not large enough. This
+       should be extremely rare, as a vector of size 1000 is used.
+
+         PCRE_ERROR_DFA_BADRESTART (-30)
+
+       When pcre_dfa_exec() is called with the PCRE_DFA_RESTART  option,  some
+       plausibility  checks  are  made on the contents of the workspace, which
+       should contain data about the previous partial match. If any  of  these
+       checks fail, this error is given.
+
+
+SEE ALSO
+
+       pcre16(3),   pcre32(3),  pcrebuild(3),  pcrecallout(3),  pcrecpp(3)(3),
+       pcrematching(3), pcrepartial(3), pcreposix(3), pcreprecompile(3), pcre-
+       sample(3), pcrestack(3).
+
+
+AUTHOR
+
+       Philip Hazel
+       University Computing Service
+       Cambridge CB2 3QH, England.
+
+
+REVISION
+
+       Last updated: 09 February 2014
+       Copyright (c) 1997-2014 University of Cambridge.
+------------------------------------------------------------------------------
+
+
+PCRECALLOUT(3)             Library Functions Manual             PCRECALLOUT(3)
+
+
+
+NAME
+       PCRE - Perl-compatible regular expressions
+
+SYNOPSIS
+
+       #include <pcre.h>
+
+       int (*pcre_callout)(pcre_callout_block *);
+
+       int (*pcre16_callout)(pcre16_callout_block *);
+
+       int (*pcre32_callout)(pcre32_callout_block *);
+
+
+DESCRIPTION
+
+       PCRE provides a feature called "callout", which is a means of temporar-
+       ily passing control to the caller of PCRE  in  the  middle  of  pattern
+       matching.  The  caller of PCRE provides an external function by putting
+       its entry point in the global variable pcre_callout (pcre16_callout for
+       the 16-bit library, pcre32_callout for the 32-bit library). By default,
+       this variable contains NULL, which disables all calling out.
+
+       Within a regular expression, (?C) indicates the  points  at  which  the
+       external  function  is  to  be  called. Different callout points can be
+       identified by putting a number less than 256 after the  letter  C.  The
+       default  value  is  zero.   For  example,  this pattern has two callout
+       points:
+
+         (?C1)abc(?C2)def
+
+       If the PCRE_AUTO_CALLOUT option bit is set when a pattern is  compiled,
+       PCRE  automatically  inserts callouts, all with number 255, before each
+       item in the pattern. For example, if PCRE_AUTO_CALLOUT is used with the
+       pattern
+
+         A(\d{2}|--)
+
+       it is processed as if it were
+
+       (?C255)A(?C255)((?C255)\d{2}(?C255)|(?C255)-(?C255)-(?C255))(?C255)
+
+       Notice  that  there  is a callout before and after each parenthesis and
+       alternation bar. If the pattern contains a conditional group whose con-
+       dition  is  an  assertion, an automatic callout is inserted immediately
+       before the condition. Such a callout may also be  inserted  explicitly,
+       for example:
+
+         (?(?C9)(?=a)ab|de)
+
+       This  applies only to assertion conditions (because they are themselves
+       independent groups).
+
+       Automatic callouts can be used for tracking  the  progress  of  pattern
+       matching.   The pcretest program has a pattern qualifier (/C) that sets
+       automatic callouts; when it is used, the output indicates how the  pat-
+       tern  is  being matched. This is useful information when you are trying
+       to optimize the performance of a particular pattern.
+
+
+MISSING CALLOUTS
+
+       You should be aware that, because of optimizations in the way PCRE com-
+       piles and matches patterns, callouts sometimes do not happen exactly as
+       you might expect.
+
+       At compile time, PCRE "auto-possessifies" repeated items when it  knows
+       that  what follows cannot be part of the repeat. For example, a+[bc] is
+       compiled as if it were a++[bc]. The pcretest output when  this  pattern
+       is  anchored  and  then  applied  with automatic callouts to the string
+       "aaaa" is:
+
+         --->aaaa
+          +0 ^        ^
+          +1 ^        a+
+          +3 ^   ^    [bc]
+         No match
+
+       This indicates that when matching [bc] fails, there is no  backtracking
+       into  a+  and  therefore the callouts that would be taken for the back-
+       tracks do not occur.  You can disable the  auto-possessify  feature  by
+       passing PCRE_NO_AUTO_POSSESS to pcre_compile(), or starting the pattern
+       with (*NO_AUTO_POSSESS). If this is done  in  pcretest  (using  the  /O
+       qualifier), the output changes to this:
+
+         --->aaaa
+          +0 ^        ^
+          +1 ^        a+
+          +3 ^   ^    [bc]
+          +3 ^  ^     [bc]
+          +3 ^ ^      [bc]
+          +3 ^^       [bc]
+         No match
+
+       This time, when matching [bc] fails, the matcher backtracks into a+ and
+       tries again, repeatedly, until a+ itself fails.
+
+       Other optimizations that provide fast "no match"  results  also  affect
+       callouts.  For example, if the pattern is
+
+         ab(?C4)cd
+
+       PCRE knows that any matching string must contain the letter "d". If the
+       subject string is "abyz", the lack of "d" means that  matching  doesn't
+       ever  start,  and  the  callout is never reached. However, with "abyd",
+       though the result is still no match, the callout is obeyed.
+
+       If the pattern is studied, PCRE knows the minimum length of a  matching
+       string,  and will immediately give a "no match" return without actually
+       running a match if the subject is not long enough, or,  for  unanchored
+       patterns, if it has been scanned far enough.
+
+       You  can disable these optimizations by passing the PCRE_NO_START_OPTI-
+       MIZE option to the matching function, or by starting the  pattern  with
+       (*NO_START_OPT).  This slows down the matching process, but does ensure
+       that callouts such as the example above are obeyed.
+
+
+THE CALLOUT INTERFACE
+
+       During matching, when PCRE reaches a callout point, the external  func-
+       tion defined by pcre_callout or pcre[16|32]_callout is called (if it is
+       set). This applies to both normal and DFA matching. The  only  argument
+       to   the   callout   function   is  a  pointer  to  a  pcre_callout  or
+       pcre[16|32]_callout block.  These  structures  contains  the  following
+       fields:
+
+         int           version;
+         int           callout_number;
+         int          *offset_vector;
+         const char   *subject;           (8-bit version)
+         PCRE_SPTR16   subject;           (16-bit version)
+         PCRE_SPTR32   subject;           (32-bit version)
+         int           subject_length;
+         int           start_match;
+         int           current_position;
+         int           capture_top;
+         int           capture_last;
+         void         *callout_data;
+         int           pattern_position;
+         int           next_item_length;
+         const unsigned char *mark;       (8-bit version)
+         const PCRE_UCHAR16  *mark;       (16-bit version)
+         const PCRE_UCHAR32  *mark;       (32-bit version)
+
+       The  version  field  is an integer containing the version number of the
+       block format. The initial version was 0; the current version is 2.  The
+       version  number  will  change  again in future if additional fields are
+       added, but the intention is never to remove any of the existing fields.
+
+       The callout_number field contains the number of the  callout,  as  com-
+       piled  into  the pattern (that is, the number after ?C for manual call-
+       outs, and 255 for automatically generated callouts).
+
+       The offset_vector field is a pointer to the vector of offsets that  was
+       passed  by  the  caller  to  the matching function. When pcre_exec() or
+       pcre[16|32]_exec() is used, the contents can be inspected, in order  to
+       extract  substrings  that  have been matched so far, in the same way as
+       for extracting substrings after a match  has  completed.  For  the  DFA
+       matching functions, this field is not useful.
+
+       The subject and subject_length fields contain copies of the values that
+       were passed to the matching function.
+
+       The start_match field normally contains the offset within  the  subject
+       at  which  the  current  match  attempt started. However, if the escape
+       sequence \K has been encountered, this value is changed to reflect  the
+       modified  starting  point.  If the pattern is not anchored, the callout
+       function may be called several times from the same point in the pattern
+       for different starting points in the subject.
+
+       The  current_position  field  contains the offset within the subject of
+       the current match pointer.
+
+       When the pcre_exec() or pcre[16|32]_exec()  is  used,  the  capture_top
+       field  contains  one  more than the number of the highest numbered cap-
+       tured substring so far. If no substrings have been captured, the  value
+       of  capture_top  is one. This is always the case when the DFA functions
+       are used, because they do not support captured substrings.
+
+       The capture_last field contains the number of the  most  recently  cap-
+       tured  substring. However, when a recursion exits, the value reverts to
+       what it was outside the recursion, as do the  values  of  all  captured
+       substrings.  If  no  substrings  have  been captured, the value of cap-
+       ture_last is -1. This is always the case for  the  DFA  matching  func-
+       tions.
+
+       The  callout_data  field  contains a value that is passed to a matching
+       function specifically so that it can be passed back in callouts. It  is
+       passed  in  the callout_data field of a pcre_extra or pcre[16|32]_extra
+       data structure. If no such data was passed, the value  of  callout_data
+       in  a  callout  block is NULL. There is a description of the pcre_extra
+       structure in the pcreapi documentation.
+
+       The pattern_position field is present from version  1  of  the  callout
+       structure. It contains the offset to the next item to be matched in the
+       pattern string.
+
+       The next_item_length field is present from version  1  of  the  callout
+       structure. It contains the length of the next item to be matched in the
+       pattern string. When the callout immediately  precedes  an  alternation
+       bar,  a  closing  parenthesis, or the end of the pattern, the length is
+       zero. When the callout precedes an opening parenthesis, the  length  is
+       that of the entire subpattern.
+
+       The  pattern_position  and next_item_length fields are intended to help
+       in distinguishing between different automatic callouts, which all  have
+       the same callout number. However, they are set for all callouts.
+
+       The  mark  field is present from version 2 of the callout structure. In
+       callouts from pcre_exec() or pcre[16|32]_exec() it contains  a  pointer
+       to  the  zero-terminated  name  of  the  most  recently passed (*MARK),
+       (*PRUNE), or (*THEN) item in the match, or NULL if no such  items  have
+       been  passed.  Instances  of  (*PRUNE) or (*THEN) without a name do not
+       obliterate a previous (*MARK). In callouts from the DFA matching  func-
+       tions this field always contains NULL.
+
+
+RETURN VALUES
+
+       The  external callout function returns an integer to PCRE. If the value
+       is zero, matching proceeds as normal. If  the  value  is  greater  than
+       zero,  matching  fails  at  the current point, but the testing of other
+       matching possibilities goes ahead, just as if a lookahead assertion had
+       failed.  If  the  value  is less than zero, the match is abandoned, the
+       matching function returns the negative value.
+
+       Negative  values  should  normally  be   chosen   from   the   set   of
+       PCRE_ERROR_xxx values. In particular, PCRE_ERROR_NOMATCH forces a stan-
+       dard "no  match"  failure.   The  error  number  PCRE_ERROR_CALLOUT  is
+       reserved  for  use  by callout functions; it will never be used by PCRE
+       itself.
+
+
+AUTHOR
+
+       Philip Hazel
+       University Computing Service
+       Cambridge CB2 3QH, England.
+
+
+REVISION
+
+       Last updated: 12 November 2013
+       Copyright (c) 1997-2013 University of Cambridge.
+------------------------------------------------------------------------------
+
+
+PCRECOMPAT(3)              Library Functions Manual              PCRECOMPAT(3)
+
+
+
+NAME
+       PCRE - Perl-compatible regular expressions
+
+DIFFERENCES BETWEEN PCRE AND PERL
+
+       This  document describes the differences in the ways that PCRE and Perl
+       handle regular expressions. The differences  described  here  are  with
+       respect to Perl versions 5.10 and above.
+
+       1. PCRE has only a subset of Perl's Unicode support. Details of what it
+       does have are given in the pcreunicode page.
+
+       2. PCRE allows repeat quantifiers only on parenthesized assertions, but
+       they  do  not mean what you might think. For example, (?!a){3} does not
+       assert that the next three characters are not "a". It just asserts that
+       the next character is not "a" three times (in principle: PCRE optimizes
+       this to run the assertion just once). Perl allows repeat quantifiers on
+       other assertions such as \b, but these do not seem to have any use.
+
+       3.  Capturing  subpatterns  that occur inside negative lookahead asser-
+       tions are counted, but their entries in the offsets  vector  are  never
+       set.  Perl sometimes (but not always) sets its numerical variables from
+       inside negative assertions.
+
+       4. Though binary zero characters are supported in the  subject  string,
+       they are not allowed in a pattern string because it is passed as a nor-
+       mal C string, terminated by zero. The escape sequence \0 can be used in
+       the pattern to represent a binary zero.
+
+       5.  The  following Perl escape sequences are not supported: \l, \u, \L,
+       \U, and \N when followed by a character name or Unicode value.  (\N  on
+       its own, matching a non-newline character, is supported.) In fact these
+       are implemented by Perl's general string-handling and are not  part  of
+       its  pattern  matching engine. If any of these are encountered by PCRE,
+       an error is generated by default. However, if the  PCRE_JAVASCRIPT_COM-
+       PAT  option  is set, \U and \u are interpreted as JavaScript interprets
+       them.
+
+       6. The Perl escape sequences \p, \P, and \X are supported only if  PCRE
+       is  built  with Unicode character property support. The properties that
+       can be tested with \p and \P are limited to the general category  prop-
+       erties  such  as  Lu and Nd, script names such as Greek or Han, and the
+       derived properties Any and L&. PCRE does  support  the  Cs  (surrogate)
+       property,  which  Perl  does  not; the Perl documentation says "Because
+       Perl hides the need for the user to understand the internal representa-
+       tion  of Unicode characters, there is no need to implement the somewhat
+       messy concept of surrogates."
+
+       7. PCRE does support the \Q...\E escape for quoting substrings. Charac-
+       ters  in  between  are  treated as literals. This is slightly different
+       from Perl in that $ and @ are  also  handled  as  literals  inside  the
+       quotes.  In Perl, they cause variable interpolation (but of course PCRE
+       does not have variables). Note the following examples:
+
+           Pattern            PCRE matches      Perl matches
+
+           \Qabc$xyz\E        abc$xyz           abc followed by the
+                                                  contents of $xyz
+           \Qabc\$xyz\E       abc\$xyz          abc\$xyz
+           \Qabc\E\$\Qxyz\E   abc$xyz           abc$xyz
+
+       The \Q...\E sequence is recognized both inside  and  outside  character
+       classes.
+
+       8. Fairly obviously, PCRE does not support the (?{code}) and (??{code})
+       constructions. However, there is support for recursive  patterns.  This
+       is  not  available  in Perl 5.8, but it is in Perl 5.10. Also, the PCRE
+       "callout" feature allows an external function to be called during  pat-
+       tern matching. See the pcrecallout documentation for details.
+
+       9.  Subpatterns  that  are called as subroutines (whether or not recur-
+       sively) are always treated as atomic  groups  in  PCRE.  This  is  like
+       Python,  but  unlike Perl.  Captured values that are set outside a sub-
+       routine call can be reference from inside in PCRE,  but  not  in  Perl.
+       There is a discussion that explains these differences in more detail in
+       the section on recursion differences from Perl in the pcrepattern page.
+
+       10. If any of the backtracking control verbs are used in  a  subpattern
+       that  is  called  as  a  subroutine (whether or not recursively), their
+       effect is confined to that subpattern; it does not extend to  the  sur-
+       rounding  pattern.  This is not always the case in Perl. In particular,
+       if (*THEN) is present in a group that is called as  a  subroutine,  its
+       action is limited to that group, even if the group does not contain any
+       | characters. Note that such subpatterns are processed as  anchored  at
+       the point where they are tested.
+
+       11.  If a pattern contains more than one backtracking control verb, the
+       first one that is backtracked onto acts. For example,  in  the  pattern
+       A(*COMMIT)B(*PRUNE)C  a  failure in B triggers (*COMMIT), but a failure
+       in C triggers (*PRUNE). Perl's behaviour is more complex; in many cases
+       it is the same as PCRE, but there are examples where it differs.
+
+       12.  Most  backtracking  verbs in assertions have their normal actions.
+       They are not confined to the assertion.
+
+       13. There are some differences that are concerned with the settings  of
+       captured  strings  when  part  of  a  pattern is repeated. For example,
+       matching "aba" against the  pattern  /^(a(b)?)+$/  in  Perl  leaves  $2
+       unset, but in PCRE it is set to "b".
+
+       14.  PCRE's handling of duplicate subpattern numbers and duplicate sub-
+       pattern names is not as general as Perl's. This is a consequence of the
+       fact the PCRE works internally just with numbers, using an external ta-
+       ble to translate between numbers and names. In  particular,  a  pattern
+       such  as  (?|(?<a>A)|(?<b)B),  where the two capturing parentheses have
+       the same number but different names, is not supported,  and  causes  an
+       error  at compile time. If it were allowed, it would not be possible to
+       distinguish which parentheses matched, because both names map  to  cap-
+       turing subpattern number 1. To avoid this confusing situation, an error
+       is given at compile time.
+
+       15. Perl recognizes comments in some places that  PCRE  does  not,  for
+       example,  between  the  ( and ? at the start of a subpattern. If the /x
+       modifier is set, Perl allows white space between ( and ?  (though  cur-
+       rent  Perls  warn that this is deprecated) but PCRE never does, even if
+       the PCRE_EXTENDED option is set.
+
+       16. Perl, when in warning mode, gives warnings  for  character  classes
+       such  as  [A-\d] or [a-[:digit:]]. It then treats the hyphens as liter-
+       als. PCRE has no warning features, so it gives an error in these  cases
+       because they are almost certainly user mistakes.
+
+       17.  In  PCRE,  the upper/lower case character properties Lu and Ll are
+       not affected when case-independent matching is specified. For  example,
+       \p{Lu} always matches an upper case letter. I think Perl has changed in
+       this respect; in the release at the time of writing (5.16), \p{Lu}  and
+       \p{Ll} match all letters, regardless of case, when case independence is
+       specified.
+
+       18. PCRE provides some extensions to the Perl regular expression facil-
+       ities.   Perl  5.10  includes new features that are not in earlier ver-
+       sions of Perl, some of which (such as named parentheses) have  been  in
+       PCRE for some time. This list is with respect to Perl 5.10:
+
+       (a)  Although  lookbehind  assertions  in  PCRE must match fixed length
+       strings, each alternative branch of a lookbehind assertion can match  a
+       different  length  of  string.  Perl requires them all to have the same
+       length.
+
+       (b) If PCRE_DOLLAR_ENDONLY is set and PCRE_MULTILINE is not set, the  $
+       meta-character matches only at the very end of the string.
+
+       (c) If PCRE_EXTRA is set, a backslash followed by a letter with no spe-
+       cial meaning is faulted. Otherwise, like Perl, the backslash is quietly
+       ignored.  (Perl can be made to issue a warning.)
+
+       (d)  If  PCRE_UNGREEDY is set, the greediness of the repetition quanti-
+       fiers is inverted, that is, by default they are not greedy, but if fol-
+       lowed by a question mark they are.
+
+       (e) PCRE_ANCHORED can be used at matching time to force a pattern to be
+       tried only at the first matching position in the subject string.
+
+       (f) The PCRE_NOTBOL, PCRE_NOTEOL, PCRE_NOTEMPTY, PCRE_NOTEMPTY_ATSTART,
+       and  PCRE_NO_AUTO_CAPTURE  options for pcre_exec() have no Perl equiva-
+       lents.
+
+       (g) The \R escape sequence can be restricted to match only CR,  LF,  or
+       CRLF by the PCRE_BSR_ANYCRLF option.
+
+       (h) The callout facility is PCRE-specific.
+
+       (i) The partial matching facility is PCRE-specific.
+
+       (j) Patterns compiled by PCRE can be saved and re-used at a later time,
+       even on different hosts that have the other endianness.  However,  this
+       does not apply to optimized data created by the just-in-time compiler.
+
+       (k)    The    alternative    matching    functions    (pcre_dfa_exec(),
+       pcre16_dfa_exec() and pcre32_dfa_exec(),) match in a different way  and
+       are not Perl-compatible.
+
+       (l)  PCRE  recognizes some special sequences such as (*CR) at the start
+       of a pattern that set overall options that cannot be changed within the
+       pattern.
+
+
+AUTHOR
+
+       Philip Hazel
+       University Computing Service
+       Cambridge CB2 3QH, England.
+
+
+REVISION
+
+       Last updated: 10 November 2013
+       Copyright (c) 1997-2013 University of Cambridge.
+------------------------------------------------------------------------------
+
+
+PCREPATTERN(3)             Library Functions Manual             PCREPATTERN(3)
+
+
+
+NAME
+       PCRE - Perl-compatible regular expressions
+
+PCRE REGULAR EXPRESSION DETAILS
+
+       The  syntax and semantics of the regular expressions that are supported
+       by PCRE are described in detail below. There is a quick-reference  syn-
+       tax summary in the pcresyntax page. PCRE tries to match Perl syntax and
+       semantics as closely as it can. PCRE  also  supports  some  alternative
+       regular  expression  syntax (which does not conflict with the Perl syn-
+       tax) in order to provide some compatibility with regular expressions in
+       Python, .NET, and Oniguruma.
+
+       Perl's  regular expressions are described in its own documentation, and
+       regular expressions in general are covered in a number of  books,  some
+       of  which  have  copious  examples. Jeffrey Friedl's "Mastering Regular
+       Expressions", published by  O'Reilly,  covers  regular  expressions  in
+       great  detail.  This  description  of  PCRE's  regular  expressions  is
+       intended as reference material.
+
+       This document discusses the patterns that are supported  by  PCRE  when
+       one    its    main   matching   functions,   pcre_exec()   (8-bit)   or
+       pcre[16|32]_exec() (16- or 32-bit), is used. PCRE also has  alternative
+       matching  functions,  pcre_dfa_exec()  and pcre[16|32_dfa_exec(), which
+       match using a different algorithm that is not Perl-compatible. Some  of
+       the  features  discussed  below  are not available when DFA matching is
+       used. The advantages and disadvantages of  the  alternative  functions,
+       and  how  they  differ  from the normal functions, are discussed in the
+       pcrematching page.
+
+
+SPECIAL START-OF-PATTERN ITEMS
+
+       A number of options that can be passed to pcre_compile()  can  also  be
+       set by special items at the start of a pattern. These are not Perl-com-
+       patible, but are provided to make these options accessible  to  pattern
+       writers  who are not able to change the program that processes the pat-
+       tern. Any number of these items  may  appear,  but  they  must  all  be
+       together right at the start of the pattern string, and the letters must
+       be in upper case.
+
+   UTF support
+
+       The original operation of PCRE was on strings of  one-byte  characters.
+       However,  there  is  now also support for UTF-8 strings in the original
+       library, an extra library that supports  16-bit  and  UTF-16  character
+       strings,  and a third library that supports 32-bit and UTF-32 character
+       strings. To use these features, PCRE must be built to include appropri-
+       ate  support. When using UTF strings you must either call the compiling
+       function with the PCRE_UTF8, PCRE_UTF16, or PCRE_UTF32 option,  or  the
+       pattern must start with one of these special sequences:
+
+         (*UTF8)
+         (*UTF16)
+         (*UTF32)
+         (*UTF)
+
+       (*UTF)  is  a  generic  sequence  that  can  be  used  with  any of the
+       libraries.  Starting a pattern with such a sequence  is  equivalent  to
+       setting  the  relevant  option.  How setting a UTF mode affects pattern
+       matching is mentioned in several places below. There is also a  summary
+       of features in the pcreunicode page.
+
+       Some applications that allow their users to supply patterns may wish to
+       restrict  them  to  non-UTF  data  for   security   reasons.   If   the
+       PCRE_NEVER_UTF  option  is  set  at  compile  time, (*UTF) etc. are not
+       allowed, and their appearance causes an error.
+
+   Unicode property support
+
+       Another special sequence that may appear at the start of a  pattern  is
+       (*UCP).   This  has  the same effect as setting the PCRE_UCP option: it
+       causes sequences such as \d and \w to use Unicode properties to  deter-
+       mine character types, instead of recognizing only characters with codes
+       less than 128 via a lookup table.
+
+   Disabling auto-possessification
+
+       If a pattern starts with (*NO_AUTO_POSSESS), it has the same effect  as
+       setting  the  PCRE_NO_AUTO_POSSESS  option  at compile time. This stops
+       PCRE from making quantifiers possessive when what follows cannot  match
+       the  repeated item. For example, by default a+b is treated as a++b. For
+       more details, see the pcreapi documentation.
+
+   Disabling start-up optimizations
+
+       If a pattern starts with (*NO_START_OPT), it has  the  same  effect  as
+       setting the PCRE_NO_START_OPTIMIZE option either at compile or matching
+       time. This disables several  optimizations  for  quickly  reaching  "no
+       match" results. For more details, see the pcreapi documentation.
+
+   Newline conventions
+
+       PCRE  supports five different conventions for indicating line breaks in
+       strings: a single CR (carriage return) character, a  single  LF  (line-
+       feed) character, the two-character sequence CRLF, any of the three pre-
+       ceding, or any Unicode newline sequence. The pcreapi page  has  further
+       discussion  about newlines, and shows how to set the newline convention
+       in the options arguments for the compiling and matching functions.
+
+       It is also possible to specify a newline convention by starting a  pat-
+       tern string with one of the following five sequences:
+
+         (*CR)        carriage return
+         (*LF)        linefeed
+         (*CRLF)      carriage return, followed by linefeed
+         (*ANYCRLF)   any of the three above
+         (*ANY)       all Unicode newline sequences
+
+       These override the default and the options given to the compiling func-
+       tion. For example, on a Unix system where LF  is  the  default  newline
+       sequence, the pattern
+
+         (*CR)a.b
+
+       changes the convention to CR. That pattern matches "a\nb" because LF is
+       no longer a newline. If more than one of these settings is present, the
+       last one is used.
+
+       The  newline  convention affects where the circumflex and dollar asser-
+       tions are true. It also affects the interpretation of the dot metachar-
+       acter when PCRE_DOTALL is not set, and the behaviour of \N. However, it
+       does not affect what the \R escape sequence matches. By  default,  this
+       is  any Unicode newline sequence, for Perl compatibility. However, this
+       can be changed; see the description of \R in the section entitled "New-
+       line  sequences"  below.  A change of \R setting can be combined with a
+       change of newline convention.
+
+   Setting match and recursion limits
+
+       The caller of pcre_exec() can set a limit on the number  of  times  the
+       internal  match() function is called and on the maximum depth of recur-
+       sive calls. These facilities are provided to catch runaway matches that
+       are provoked by patterns with huge matching trees (a typical example is
+       a pattern with nested unlimited repeats) and to avoid  running  out  of
+       system  stack  by  too  much  recursion.  When  one  of these limits is
+       reached, pcre_exec() gives an error return. The limits can also be  set
+       by items at the start of the pattern of the form
+
+         (*LIMIT_MATCH=d)
+         (*LIMIT_RECURSION=d)
+
+       where d is any number of decimal digits. However, the value of the set-
+       ting must be less than the value set (or defaulted) by  the  caller  of
+       pcre_exec()  for  it  to  have  any effect. In other words, the pattern
+       writer can lower the limits set by the programmer, but not raise  them.
+       If  there  is  more  than one setting of one of these limits, the lower
+       value is used.
+
+
+EBCDIC CHARACTER CODES
+
+       PCRE can be compiled to run in an environment that uses EBCDIC  as  its
+       character code rather than ASCII or Unicode (typically a mainframe sys-
+       tem). In the sections below, character code values are  ASCII  or  Uni-
+       code; in an EBCDIC environment these characters may have different code
+       values, and there are no code points greater than 255.
+
+
+CHARACTERS AND METACHARACTERS
+
+       A regular expression is a pattern that is  matched  against  a  subject
+       string  from  left  to right. Most characters stand for themselves in a
+       pattern, and match the corresponding characters in the  subject.  As  a
+       trivial example, the pattern
+
+         The quick brown fox
+
+       matches a portion of a subject string that is identical to itself. When
+       caseless matching is specified (the PCRE_CASELESS option), letters  are
+       matched  independently  of case. In a UTF mode, PCRE always understands
+       the concept of case for characters whose values are less than  128,  so
+       caseless  matching  is always possible. For characters with higher val-
+       ues, the concept of case is supported if PCRE is compiled with  Unicode
+       property  support,  but  not  otherwise.   If  you want to use caseless
+       matching for characters 128 and above, you must  ensure  that  PCRE  is
+       compiled with Unicode property support as well as with UTF support.
+
+       The  power  of  regular  expressions  comes from the ability to include
+       alternatives and repetitions in the pattern. These are encoded  in  the
+       pattern by the use of metacharacters, which do not stand for themselves
+       but instead are interpreted in some special way.
+
+       There are two different sets of metacharacters: those that  are  recog-
+       nized  anywhere in the pattern except within square brackets, and those
+       that are recognized within square brackets.  Outside  square  brackets,
+       the metacharacters are as follows:
+
+         \      general escape character with several uses
+         ^      assert start of string (or line, in multiline mode)
+         $      assert end of string (or line, in multiline mode)
+         .      match any character except newline (by default)
+         [      start character class definition
+         |      start of alternative branch
+         (      start subpattern
+         )      end subpattern
+         ?      extends the meaning of (
+                also 0 or 1 quantifier
+                also quantifier minimizer
+         *      0 or more quantifier
+         +      1 or more quantifier
+                also "possessive quantifier"
+         {      start min/max quantifier
+
+       Part  of  a  pattern  that is in square brackets is called a "character
+       class". In a character class the only metacharacters are:
+
+         \      general escape character
+         ^      negate the class, but only if the first character
+         -      indicates character range
+         [      POSIX character class (only if followed by POSIX
+                  syntax)
+         ]      terminates the character class
+
+       The following sections describe the use of each of the metacharacters.
+
+
+BACKSLASH
+
+       The backslash character has several uses. Firstly, if it is followed by
+       a character that is not a number or a letter, it takes away any special
+       meaning that character may have. This use of  backslash  as  an  escape
+       character applies both inside and outside character classes.
+
+       For  example,  if  you want to match a * character, you write \* in the
+       pattern.  This escaping action applies whether  or  not  the  following
+       character  would  otherwise be interpreted as a metacharacter, so it is
+       always safe to precede a non-alphanumeric  with  backslash  to  specify
+       that  it stands for itself. In particular, if you want to match a back-
+       slash, you write \\.
+
+       In a UTF mode, only ASCII numbers and letters have any special  meaning
+       after  a  backslash.  All  other characters (in particular, those whose
+       codepoints are greater than 127) are treated as literals.
+
+       If a pattern is compiled with  the  PCRE_EXTENDED  option,  most  white
+       space  in the pattern (other than in a character class), and characters
+       between a # outside a character class and the next newline,  inclusive,
+       are ignored. An escaping backslash can be used to include a white space
+       or # character as part of the pattern.
+
+       If you want to remove the special meaning from a  sequence  of  charac-
+       ters,  you can do so by putting them between \Q and \E. This is differ-
+       ent from Perl in that $ and  @  are  handled  as  literals  in  \Q...\E
+       sequences  in  PCRE, whereas in Perl, $ and @ cause variable interpola-
+       tion. Note the following examples:
+
+         Pattern            PCRE matches   Perl matches
+
+         \Qabc$xyz\E        abc$xyz        abc followed by the
+                                             contents of $xyz
+         \Qabc\$xyz\E       abc\$xyz       abc\$xyz
+         \Qabc\E\$\Qxyz\E   abc$xyz        abc$xyz
+
+       The \Q...\E sequence is recognized both inside  and  outside  character
+       classes.   An  isolated \E that is not preceded by \Q is ignored. If \Q
+       is not followed by \E later in the pattern, the literal  interpretation
+       continues  to  the  end  of  the pattern (that is, \E is assumed at the
+       end). If the isolated \Q is inside a character class,  this  causes  an
+       error, because the character class is not terminated.
+
+   Non-printing characters
+
+       A second use of backslash provides a way of encoding non-printing char-
+       acters in patterns in a visible manner. There is no restriction on  the
+       appearance  of non-printing characters, apart from the binary zero that
+       terminates a pattern, but when a pattern  is  being  prepared  by  text
+       editing,  it  is  often  easier  to  use  one  of  the following escape
+       sequences than the binary character it represents:
+
+         \a        alarm, that is, the BEL character (hex 07)
+         \cx       "control-x", where x is any ASCII character
+         \e        escape (hex 1B)
+         \f        form feed (hex 0C)
+         \n        linefeed (hex 0A)
+         \r        carriage return (hex 0D)
+         \t        tab (hex 09)
+         \0dd      character with octal code 0dd
+         \ddd      character with octal code ddd, or back reference
+         \o{ddd..} character with octal code ddd..
+         \xhh      character with hex code hh
+         \x{hhh..} character with hex code hhh.. (non-JavaScript mode)
+         \uhhhh    character with hex code hhhh (JavaScript mode only)
+
+       The precise effect of \cx on ASCII characters is as follows: if x is  a
+       lower  case  letter,  it  is converted to upper case. Then bit 6 of the
+       character (hex 40) is inverted. Thus \cA to \cZ become hex 01 to hex 1A
+       (A  is  41, Z is 5A), but \c{ becomes hex 3B ({ is 7B), and \c; becomes
+       hex 7B (; is 3B). If the data item (byte or 16-bit value) following  \c
+       has  a  value greater than 127, a compile-time error occurs. This locks
+       out non-ASCII characters in all modes.
+
+       The \c facility was designed for use with ASCII  characters,  but  with
+       the  extension  to  Unicode it is even less useful than it once was. It
+       is, however, recognized when PCRE is compiled  in  EBCDIC  mode,  where
+       data  items  are always bytes. In this mode, all values are valid after
+       \c. If the next character is a lower case letter, it  is  converted  to
+       upper  case.  Then  the  0xc0  bits  of the byte are inverted. Thus \cA
+       becomes hex 01, as in ASCII (A is C1), but because the  EBCDIC  letters
+       are  disjoint,  \cZ becomes hex 29 (Z is E9), and other characters also
+       generate different values.
+
+       After \0 up to two further octal digits are read. If  there  are  fewer
+       than  two  digits,  just  those  that  are  present  are used. Thus the
+       sequence \0\x\07 specifies two binary zeros followed by a BEL character
+       (code  value 7). Make sure you supply two digits after the initial zero
+       if the pattern character that follows is itself an octal digit.
+
+       The escape \o must be followed by a sequence of octal digits,  enclosed
+       in  braces.  An  error occurs if this is not the case. This escape is a
+       recent addition to Perl; it provides way of specifying  character  code
+       points  as  octal  numbers  greater than 0777, and it also allows octal
+       numbers and back references to be unambiguously specified.
+
+       For greater clarity and unambiguity, it is best to avoid following \ by
+       a digit greater than zero. Instead, use \o{} or \x{} to specify charac-
+       ter numbers, and \g{} to specify back references. The  following  para-
+       graphs describe the old, ambiguous syntax.
+
+       The handling of a backslash followed by a digit other than 0 is compli-
+       cated, and Perl has changed in recent releases, causing  PCRE  also  to
+       change. Outside a character class, PCRE reads the digit and any follow-
+       ing digits as a decimal number. If the number is less  than  8,  or  if
+       there  have been at least that many previous capturing left parentheses
+       in the expression, the entire sequence is taken as a back reference.  A
+       description  of how this works is given later, following the discussion
+       of parenthesized subpatterns.
+
+       Inside a character class, or if  the  decimal  number  following  \  is
+       greater than 7 and there have not been that many capturing subpatterns,
+       PCRE handles \8 and \9 as the literal characters "8" and "9", and  oth-
+       erwise re-reads up to three octal digits following the backslash, using
+       them to generate a data character.  Any  subsequent  digits  stand  for
+       themselves. For example:
+
+         \040   is another way of writing an ASCII space
+         \40    is the same, provided there are fewer than 40
+                   previous capturing subpatterns
+         \7     is always a back reference
+         \11    might be a back reference, or another way of
+                   writing a tab
+         \011   is always a tab
+         \0113  is a tab followed by the character "3"
+         \113   might be a back reference, otherwise the
+                   character with octal code 113
+         \377   might be a back reference, otherwise
+                   the value 255 (decimal)
+         \81    is either a back reference, or the two
+                   characters "8" and "1"
+
+       Note  that octal values of 100 or greater that are specified using this
+       syntax must not be introduced by a leading zero, because no  more  than
+       three octal digits are ever read.
+
+       By  default, after \x that is not followed by {, from zero to two hexa-
+       decimal digits are read (letters can be in upper or  lower  case).  Any
+       number of hexadecimal digits may appear between \x{ and }. If a charac-
+       ter other than a hexadecimal digit appears between \x{  and  },  or  if
+       there is no terminating }, an error occurs.
+
+       If  the  PCRE_JAVASCRIPT_COMPAT option is set, the interpretation of \x
+       is as just described only when it is followed by two  hexadecimal  dig-
+       its.   Otherwise,  it  matches  a  literal "x" character. In JavaScript
+       mode, support for code points greater than 256 is provided by \u, which
+       must  be  followed  by  four hexadecimal digits; otherwise it matches a
+       literal "u" character.
+
+       Characters whose value is less than 256 can be defined by either of the
+       two  syntaxes for \x (or by \u in JavaScript mode). There is no differ-
+       ence in the way they are handled. For example, \xdc is exactly the same
+       as \x{dc} (or \u00dc in JavaScript mode).
+
+   Constraints on character values
+
+       Characters  that  are  specified using octal or hexadecimal numbers are
+       limited to certain values, as follows:
+
+         8-bit non-UTF mode    less than 0x100
+         8-bit UTF-8 mode      less than 0x10ffff and a valid codepoint
+         16-bit non-UTF mode   less than 0x10000
+         16-bit UTF-16 mode    less than 0x10ffff and a valid codepoint
+         32-bit non-UTF mode   less than 0x100000000
+         32-bit UTF-32 mode    less than 0x10ffff and a valid codepoint
+
+       Invalid Unicode codepoints are the range  0xd800  to  0xdfff  (the  so-
+       called "surrogate" codepoints), and 0xffef.
+
+   Escape sequences in character classes
+
+       All the sequences that define a single character value can be used both
+       inside and outside character classes. In addition, inside  a  character
+       class, \b is interpreted as the backspace character (hex 08).
+
+       \N  is not allowed in a character class. \B, \R, and \X are not special
+       inside a character class. Like  other  unrecognized  escape  sequences,
+       they  are  treated  as  the  literal  characters  "B",  "R", and "X" by
+       default, but cause an error if the PCRE_EXTRA option is set. Outside  a
+       character class, these sequences have different meanings.
+
+   Unsupported escape sequences
+
+       In  Perl, the sequences \l, \L, \u, and \U are recognized by its string
+       handler and used  to  modify  the  case  of  following  characters.  By
+       default,  PCRE does not support these escape sequences. However, if the
+       PCRE_JAVASCRIPT_COMPAT option is set, \U matches a "U"  character,  and
+       \u can be used to define a character by code point, as described in the
+       previous section.
+
+   Absolute and relative back references
+
+       The sequence \g followed by an unsigned or a negative  number,  option-
+       ally  enclosed  in braces, is an absolute or relative back reference. A
+       named back reference can be coded as \g{name}. Back references are dis-
+       cussed later, following the discussion of parenthesized subpatterns.
+
+   Absolute and relative subroutine calls
+
+       For  compatibility with Oniguruma, the non-Perl syntax \g followed by a
+       name or a number enclosed either in angle brackets or single quotes, is
+       an  alternative  syntax for referencing a subpattern as a "subroutine".
+       Details are discussed later.   Note  that  \g{...}  (Perl  syntax)  and
+       \g<...>  (Oniguruma  syntax)  are  not synonymous. The former is a back
+       reference; the latter is a subroutine call.
+
+   Generic character types
+
+       Another use of backslash is for specifying generic character types:
+
+         \d     any decimal digit
+         \D     any character that is not a decimal digit
+         \h     any horizontal white space character
+         \H     any character that is not a horizontal white space character
+         \s     any white space character
+         \S     any character that is not a white space character
+         \v     any vertical white space character
+         \V     any character that is not a vertical white space character
+         \w     any "word" character
+         \W     any "non-word" character
+
+       There is also the single sequence \N, which matches a non-newline char-
+       acter.   This  is the same as the "." metacharacter when PCRE_DOTALL is
+       not set. Perl also uses \N to match characters by name; PCRE  does  not
+       support this.
+
+       Each  pair of lower and upper case escape sequences partitions the com-
+       plete set of characters into two disjoint  sets.  Any  given  character
+       matches  one, and only one, of each pair. The sequences can appear both
+       inside and outside character classes. They each match one character  of
+       the  appropriate  type.  If the current matching point is at the end of
+       the subject string, all of them fail, because there is no character  to
+       match.
+
+       For  compatibility with Perl, \s did not used to match the VT character
+       (code 11), which made it different from the the  POSIX  "space"  class.
+       However,  Perl  added  VT  at  release  5.18, and PCRE followed suit at
+       release 8.34. The default \s characters are now HT  (9),  LF  (10),  VT
+       (11),  FF  (12),  CR  (13),  and space (32), which are defined as white
+       space in the "C" locale. This list may vary if locale-specific matching
+       is  taking place. For example, in some locales the "non-breaking space"
+       character (\xA0) is recognized as white space, and  in  others  the  VT
+       character is not.
+
+       A  "word"  character is an underscore or any character that is a letter
+       or digit.  By default, the definition of letters  and  digits  is  con-
+       trolled  by PCRE's low-valued character tables, and may vary if locale-
+       specific matching is taking place (see "Locale support" in the  pcreapi
+       page).  For  example,  in  a French locale such as "fr_FR" in Unix-like
+       systems, or "french" in Windows, some character codes greater than  127
+       are  used  for  accented letters, and these are then matched by \w. The
+       use of locales with Unicode is discouraged.
+
+       By default, characters whose code points are  greater  than  127  never
+       match \d, \s, or \w, and always match \D, \S, and \W, although this may
+       vary for characters in the range 128-255 when locale-specific  matching
+       is  happening.   These  escape sequences retain their original meanings
+       from before Unicode support was available, mainly for  efficiency  rea-
+       sons.  If  PCRE  is  compiled  with  Unicode  property support, and the
+       PCRE_UCP option is set, the behaviour is changed so that Unicode  prop-
+       erties are used to determine character types, as follows:
+
+         \d  any character that matches \p{Nd} (decimal digit)
+         \s  any character that matches \p{Z} or \h or \v
+         \w  any character that matches \p{L} or \p{N}, plus underscore
+
+       The  upper case escapes match the inverse sets of characters. Note that
+       \d matches only decimal digits, whereas \w matches any  Unicode  digit,
+       as  well as any Unicode letter, and underscore. Note also that PCRE_UCP
+       affects \b, and \B because they are defined in  terms  of  \w  and  \W.
+       Matching these sequences is noticeably slower when PCRE_UCP is set.
+
+       The  sequences  \h, \H, \v, and \V are features that were added to Perl
+       at release 5.10. In contrast to the other sequences, which  match  only
+       ASCII  characters  by  default,  these always match certain high-valued
+       code points, whether or not PCRE_UCP is set. The horizontal space char-
+       acters are:
+
+         U+0009     Horizontal tab (HT)
+         U+0020     Space
+         U+00A0     Non-break space
+         U+1680     Ogham space mark
+         U+180E     Mongolian vowel separator
+         U+2000     En quad
+         U+2001     Em quad
+         U+2002     En space
+         U+2003     Em space
+         U+2004     Three-per-em space
+         U+2005     Four-per-em space
+         U+2006     Six-per-em space
+         U+2007     Figure space
+         U+2008     Punctuation space
+         U+2009     Thin space
+         U+200A     Hair space
+         U+202F     Narrow no-break space
+         U+205F     Medium mathematical space
+         U+3000     Ideographic space
+
+       The vertical space characters are:
+
+         U+000A     Linefeed (LF)
+         U+000B     Vertical tab (VT)
+         U+000C     Form feed (FF)
+         U+000D     Carriage return (CR)
+         U+0085     Next line (NEL)
+         U+2028     Line separator
+         U+2029     Paragraph separator
+
+       In 8-bit, non-UTF-8 mode, only the characters with codepoints less than
+       256 are relevant.
+
+   Newline sequences
+
+       Outside a character class, by default, the escape sequence  \R  matches
+       any  Unicode newline sequence. In 8-bit non-UTF-8 mode \R is equivalent
+       to the following:
+
+         (?>\r\n|\n|\x0b|\f|\r|\x85)
+
+       This is an example of an "atomic group", details  of  which  are  given
+       below.  This particular group matches either the two-character sequence
+       CR followed by LF, or  one  of  the  single  characters  LF  (linefeed,
+       U+000A),  VT  (vertical  tab, U+000B), FF (form feed, U+000C), CR (car-
+       riage return, U+000D), or NEL (next line,  U+0085).  The  two-character
+       sequence is treated as a single unit that cannot be split.
+
+       In  other modes, two additional characters whose codepoints are greater
+       than 255 are added: LS (line separator, U+2028) and PS (paragraph sepa-
+       rator,  U+2029).   Unicode character property support is not needed for
+       these characters to be recognized.
+
+       It is possible to restrict \R to match only CR, LF, or CRLF (instead of
+       the  complete  set  of  Unicode  line  endings)  by  setting the option
+       PCRE_BSR_ANYCRLF either at compile time or when the pattern is matched.
+       (BSR is an abbrevation for "backslash R".) This can be made the default
+       when PCRE is built; if this is the case, the  other  behaviour  can  be
+       requested  via  the  PCRE_BSR_UNICODE  option.   It is also possible to
+       specify these settings by starting a pattern string  with  one  of  the
+       following sequences:
+
+         (*BSR_ANYCRLF)   CR, LF, or CRLF only
+         (*BSR_UNICODE)   any Unicode newline sequence
+
+       These override the default and the options given to the compiling func-
+       tion, but they can themselves be  overridden  by  options  given  to  a
+       matching  function.  Note  that  these  special settings, which are not
+       Perl-compatible, are recognized only at the very start  of  a  pattern,
+       and  that  they  must  be  in  upper  case. If more than one of them is
+       present, the last one is used. They can be combined with  a  change  of
+       newline convention; for example, a pattern can start with:
+
+         (*ANY)(*BSR_ANYCRLF)
+
+       They  can also be combined with the (*UTF8), (*UTF16), (*UTF32), (*UTF)
+       or (*UCP) special sequences. Inside a character class, \R is treated as
+       an  unrecognized  escape  sequence,  and  so  matches the letter "R" by
+       default, but causes an error if PCRE_EXTRA is set.
+
+   Unicode character properties
+
+       When PCRE is built with Unicode character property support, three addi-
+       tional  escape sequences that match characters with specific properties
+       are available.  When in 8-bit non-UTF-8 mode, these  sequences  are  of
+       course  limited  to  testing  characters whose codepoints are less than
+       256, but they do work in this mode.  The extra escape sequences are:
+
+         \p{xx}   a character with the xx property
+         \P{xx}   a character without the xx property
+         \X       a Unicode extended grapheme cluster
+
+       The property names represented by xx above are limited to  the  Unicode
+       script names, the general category properties, "Any", which matches any
+       character  (including  newline),  and  some  special  PCRE   properties
+       (described  in the next section).  Other Perl properties such as "InMu-
+       sicalSymbols" are not currently supported by PCRE.  Note  that  \P{Any}
+       does not match any characters, so always causes a match failure.
+
+       Sets of Unicode characters are defined as belonging to certain scripts.
+       A character from one of these sets can be matched using a script  name.
+       For example:
+
+         \p{Greek}
+         \P{Han}
+
+       Those  that are not part of an identified script are lumped together as
+       "Common". The current list of scripts is:
+
+       Arabic, Armenian, Avestan, Balinese, Bamum, Batak,  Bengali,  Bopomofo,
+       Brahmi,  Braille, Buginese, Buhid, Canadian_Aboriginal, Carian, Chakma,
+       Cham, Cherokee, Common, Coptic, Cuneiform, Cypriot, Cyrillic,  Deseret,
+       Devanagari,   Egyptian_Hieroglyphs,   Ethiopic,  Georgian,  Glagolitic,
+       Gothic, Greek, Gujarati, Gurmukhi, Han, Hangul, Hanunoo, Hebrew,  Hira-
+       gana,   Imperial_Aramaic,  Inherited,  Inscriptional_Pahlavi,  Inscrip-
+       tional_Parthian,  Javanese,  Kaithi,   Kannada,   Katakana,   Kayah_Li,
+       Kharoshthi,  Khmer,  Lao, Latin, Lepcha, Limbu, Linear_B, Lisu, Lycian,
+       Lydian,    Malayalam,    Mandaic,    Meetei_Mayek,    Meroitic_Cursive,
+       Meroitic_Hieroglyphs,   Miao,  Mongolian,  Myanmar,  New_Tai_Lue,  Nko,
+       Ogham,   Old_Italic,   Old_Persian,   Old_South_Arabian,    Old_Turkic,
+       Ol_Chiki,  Oriya, Osmanya, Phags_Pa, Phoenician, Rejang, Runic, Samari-
+       tan, Saurashtra, Sharada, Shavian,  Sinhala,  Sora_Sompeng,  Sundanese,
+       Syloti_Nagri,  Syriac,  Tagalog,  Tagbanwa, Tai_Le, Tai_Tham, Tai_Viet,
+       Takri, Tamil, Telugu, Thaana, Thai, Tibetan, Tifinagh,  Ugaritic,  Vai,
+       Yi.
+
+       Each character has exactly one Unicode general category property, spec-
+       ified by a two-letter abbreviation. For compatibility with Perl,  nega-
+       tion  can  be  specified  by including a circumflex between the opening
+       brace and the property name.  For  example,  \p{^Lu}  is  the  same  as
+       \P{Lu}.
+
+       If only one letter is specified with \p or \P, it includes all the gen-
+       eral category properties that start with that letter. In this case,  in
+       the  absence of negation, the curly brackets in the escape sequence are
+       optional; these two examples have the same effect:
+
+         \p{L}
+         \pL
+
+       The following general category property codes are supported:
+
+         C     Other
+         Cc    Control
+         Cf    Format
+         Cn    Unassigned
+         Co    Private use
+         Cs    Surrogate
+
+         L     Letter
+         Ll    Lower case letter
+         Lm    Modifier letter
+         Lo    Other letter
+         Lt    Title case letter
+         Lu    Upper case letter
+
+         M     Mark
+         Mc    Spacing mark
+         Me    Enclosing mark
+         Mn    Non-spacing mark
+
+         N     Number
+         Nd    Decimal number
+         Nl    Letter number
+         No    Other number
+
+         P     Punctuation
+         Pc    Connector punctuation
+         Pd    Dash punctuation
+         Pe    Close punctuation
+         Pf    Final punctuation
+         Pi    Initial punctuation
+         Po    Other punctuation
+         Ps    Open punctuation
+
+         S     Symbol
+         Sc    Currency symbol
+         Sk    Modifier symbol
+         Sm    Mathematical symbol
+         So    Other symbol
+
+         Z     Separator
+         Zl    Line separator
+         Zp    Paragraph separator
+         Zs    Space separator
+
+       The special property L& is also supported: it matches a character  that
+       has  the  Lu,  Ll, or Lt property, in other words, a letter that is not
+       classified as a modifier or "other".
+
+       The Cs (Surrogate) property applies only to  characters  in  the  range
+       U+D800  to U+DFFF. Such characters are not valid in Unicode strings and
+       so cannot be tested by PCRE, unless  UTF  validity  checking  has  been
+       turned    off    (see    the    discussion    of    PCRE_NO_UTF8_CHECK,
+       PCRE_NO_UTF16_CHECK and PCRE_NO_UTF32_CHECK in the pcreapi page).  Perl
+       does not support the Cs property.
+
+       The  long  synonyms  for  property  names  that  Perl supports (such as
+       \p{Letter}) are not supported by PCRE, nor is it  permitted  to  prefix
+       any of these properties with "Is".
+
+       No character that is in the Unicode table has the Cn (unassigned) prop-
+       erty.  Instead, this property is assumed for any code point that is not
+       in the Unicode table.
+
+       Specifying  caseless  matching  does not affect these escape sequences.
+       For example, \p{Lu} always matches only upper  case  letters.  This  is
+       different from the behaviour of current versions of Perl.
+
+       Matching  characters  by Unicode property is not fast, because PCRE has
+       to do a multistage table lookup in order to find  a  character's  prop-
+       erty. That is why the traditional escape sequences such as \d and \w do
+       not use Unicode properties in PCRE by default, though you can make them
+       do  so  by  setting the PCRE_UCP option or by starting the pattern with
+       (*UCP).
+
+   Extended grapheme clusters
+
+       The \X escape matches any number of Unicode  characters  that  form  an
+       "extended grapheme cluster", and treats the sequence as an atomic group
+       (see below).  Up to and including release 8.31, PCRE  matched  an  ear-
+       lier, simpler definition that was equivalent to
+
+         (?>\PM\pM*)
+
+       That  is,  it matched a character without the "mark" property, followed
+       by zero or more characters with the "mark"  property.  Characters  with
+       the  "mark"  property are typically non-spacing accents that affect the
+       preceding character.
+
+       This simple definition was extended in Unicode to include more  compli-
+       cated  kinds of composite character by giving each character a grapheme
+       breaking property, and creating rules  that  use  these  properties  to
+       define  the  boundaries  of  extended grapheme clusters. In releases of
+       PCRE later than 8.31, \X matches one of these clusters.
+
+       \X always matches at least one character. Then it  decides  whether  to
+       add additional characters according to the following rules for ending a
+       cluster:
+
+       1. End at the end of the subject string.
+
+       2. Do not end between CR and LF; otherwise end after any control  char-
+       acter.
+
+       3.  Do  not  break  Hangul (a Korean script) syllable sequences. Hangul
+       characters are of five types: L, V, T, LV, and LVT. An L character  may
+       be  followed by an L, V, LV, or LVT character; an LV or V character may
+       be followed by a V or T character; an LVT or T character may be follwed
+       only by a T character.
+
+       4.  Do not end before extending characters or spacing marks. Characters
+       with the "mark" property always have  the  "extend"  grapheme  breaking
+       property.
+
+       5. Do not end after prepend characters.
+
+       6. Otherwise, end the cluster.
+
+   PCRE's additional properties
+
+       As  well  as the standard Unicode properties described above, PCRE sup-
+       ports four more that make it possible  to  convert  traditional  escape
+       sequences  such as \w and \s to use Unicode properties. PCRE uses these
+       non-standard, non-Perl properties internally when PCRE_UCP is set. How-
+       ever, they may also be used explicitly. These properties are:
+
+         Xan   Any alphanumeric character
+         Xps   Any POSIX space character
+         Xsp   Any Perl space character
+         Xwd   Any Perl "word" character
+
+       Xan  matches  characters that have either the L (letter) or the N (num-
+       ber) property. Xps matches the characters tab, linefeed, vertical  tab,
+       form  feed,  or carriage return, and any other character that has the Z
+       (separator) property.  Xsp is the same as Xps; it used to exclude  ver-
+       tical  tab,  for Perl compatibility, but Perl changed, and so PCRE fol-
+       lowed at release 8.34. Xwd matches the same  characters  as  Xan,  plus
+       underscore.
+
+       There  is another non-standard property, Xuc, which matches any charac-
+       ter that can be represented by a Universal Character Name  in  C++  and
+       other  programming  languages.  These are the characters $, @, ` (grave
+       accent), and all characters with Unicode code points  greater  than  or
+       equal  to U+00A0, except for the surrogates U+D800 to U+DFFF. Note that
+       most base (ASCII) characters are excluded. (Universal  Character  Names
+       are  of  the  form \uHHHH or \UHHHHHHHH where H is a hexadecimal digit.
+       Note that the Xuc property does not match these sequences but the char-
+       acters that they represent.)
+
+   Resetting the match start
+
+       The  escape sequence \K causes any previously matched characters not to
+       be included in the final matched sequence. For example, the pattern:
+
+         foo\Kbar
+
+       matches "foobar", but reports that it has matched "bar".  This  feature
+       is  similar  to  a lookbehind assertion (described below).  However, in
+       this case, the part of the subject before the real match does not  have
+       to  be of fixed length, as lookbehind assertions do. The use of \K does
+       not interfere with the setting of captured  substrings.   For  example,
+       when the pattern
+
+         (foo)\Kbar
+
+       matches "foobar", the first substring is still set to "foo".
+
+       Perl  documents  that  the  use  of  \K  within assertions is "not well
+       defined". In PCRE, \K is acted upon  when  it  occurs  inside  positive
+       assertions,  but  is  ignored  in negative assertions. Note that when a
+       pattern such as (?=ab\K) matches, the reported start of the  match  can
+       be greater than the end of the match.
+
+   Simple assertions
+
+       The  final use of backslash is for certain simple assertions. An asser-
+       tion specifies a condition that has to be met at a particular point  in
+       a  match, without consuming any characters from the subject string. The
+       use of subpatterns for more complicated assertions is described  below.
+       The backslashed assertions are:
+
+         \b     matches at a word boundary
+         \B     matches when not at a word boundary
+         \A     matches at the start of the subject
+         \Z     matches at the end of the subject
+                 also matches before a newline at the end of the subject
+         \z     matches only at the end of the subject
+         \G     matches at the first matching position in the subject
+
+       Inside  a  character  class, \b has a different meaning; it matches the
+       backspace character. If any other of  these  assertions  appears  in  a
+       character  class, by default it matches the corresponding literal char-
+       acter  (for  example,  \B  matches  the  letter  B).  However,  if  the
+       PCRE_EXTRA  option is set, an "invalid escape sequence" error is gener-
+       ated instead.
+
+       A word boundary is a position in the subject string where  the  current
+       character  and  the previous character do not both match \w or \W (i.e.
+       one matches \w and the other matches \W), or the start or  end  of  the
+       string  if  the  first or last character matches \w, respectively. In a
+       UTF mode, the meanings of \w and \W  can  be  changed  by  setting  the
+       PCRE_UCP  option. When this is done, it also affects \b and \B. Neither
+       PCRE nor Perl has a separate "start of word" or "end of  word"  metase-
+       quence.  However,  whatever follows \b normally determines which it is.
+       For example, the fragment \ba matches "a" at the start of a word.
+
+       The \A, \Z, and \z assertions differ from  the  traditional  circumflex
+       and dollar (described in the next section) in that they only ever match
+       at the very start and end of the subject string, whatever  options  are
+       set.  Thus,  they are independent of multiline mode. These three asser-
+       tions are not affected by the PCRE_NOTBOL or PCRE_NOTEOL options, which
+       affect  only the behaviour of the circumflex and dollar metacharacters.
+       However, if the startoffset argument of pcre_exec() is non-zero,  indi-
+       cating that matching is to start at a point other than the beginning of
+       the subject, \A can never match. The difference between \Z  and  \z  is
+       that \Z matches before a newline at the end of the string as well as at
+       the very end, whereas \z matches only at the end.
+
+       The \G assertion is true only when the current matching position is  at
+       the  start point of the match, as specified by the startoffset argument
+       of pcre_exec(). It differs from \A when the  value  of  startoffset  is
+       non-zero.  By calling pcre_exec() multiple times with appropriate argu-
+       ments, you can mimic Perl's /g option, and it is in this kind of imple-
+       mentation where \G can be useful.
+
+       Note,  however,  that  PCRE's interpretation of \G, as the start of the
+       current match, is subtly different from Perl's, which defines it as the
+       end  of  the  previous  match. In Perl, these can be different when the
+       previously matched string was empty. Because PCRE does just  one  match
+       at a time, it cannot reproduce this behaviour.
+
+       If  all  the alternatives of a pattern begin with \G, the expression is
+       anchored to the starting match position, and the "anchored" flag is set
+       in the compiled regular expression.
+
+
+CIRCUMFLEX AND DOLLAR
+
+       The  circumflex  and  dollar  metacharacters are zero-width assertions.
+       That is, they test for a particular condition being true  without  con-
+       suming any characters from the subject string.
+
+       Outside a character class, in the default matching mode, the circumflex
+       character is an assertion that is true only  if  the  current  matching
+       point  is  at the start of the subject string. If the startoffset argu-
+       ment of pcre_exec() is non-zero, circumflex  can  never  match  if  the
+       PCRE_MULTILINE  option  is  unset. Inside a character class, circumflex
+       has an entirely different meaning (see below).
+
+       Circumflex need not be the first character of the pattern if  a  number
+       of  alternatives are involved, but it should be the first thing in each
+       alternative in which it appears if the pattern is ever  to  match  that
+       branch.  If all possible alternatives start with a circumflex, that is,
+       if the pattern is constrained to match only at the start  of  the  sub-
+       ject,  it  is  said  to be an "anchored" pattern. (There are also other
+       constructs that can cause a pattern to be anchored.)
+
+       The dollar character is an assertion that is true only if  the  current
+       matching  point  is  at  the  end of the subject string, or immediately
+       before a newline at the end of the string (by default). Note,  however,
+       that  it  does  not  actually match the newline. Dollar need not be the
+       last character of the pattern if a number of alternatives are involved,
+       but  it should be the last item in any branch in which it appears. Dol-
+       lar has no special meaning in a character class.
+
+       The meaning of dollar can be changed so that it  matches  only  at  the
+       very  end  of  the string, by setting the PCRE_DOLLAR_ENDONLY option at
+       compile time. This does not affect the \Z assertion.
+
+       The meanings of the circumflex and dollar characters are changed if the
+       PCRE_MULTILINE  option  is  set.  When  this  is the case, a circumflex
+       matches immediately after internal newlines as well as at the start  of
+       the  subject  string.  It  does not match after a newline that ends the
+       string. A dollar matches before any newlines in the string, as well  as
+       at  the very end, when PCRE_MULTILINE is set. When newline is specified
+       as the two-character sequence CRLF, isolated CR and  LF  characters  do
+       not indicate newlines.
+
+       For  example, the pattern /^abc$/ matches the subject string "def\nabc"
+       (where \n represents a newline) in multiline mode, but  not  otherwise.
+       Consequently,  patterns  that  are anchored in single line mode because
+       all branches start with ^ are not anchored in  multiline  mode,  and  a
+       match  for  circumflex  is  possible  when  the startoffset argument of
+       pcre_exec() is non-zero. The PCRE_DOLLAR_ENDONLY option is  ignored  if
+       PCRE_MULTILINE is set.
+
+       Note  that  the sequences \A, \Z, and \z can be used to match the start
+       and end of the subject in both modes, and if all branches of a  pattern
+       start  with  \A it is always anchored, whether or not PCRE_MULTILINE is
+       set.
+
+
+FULL STOP (PERIOD, DOT) AND \N
+
+       Outside a character class, a dot in the pattern matches any one charac-
+       ter  in  the subject string except (by default) a character that signi-
+       fies the end of a line.
+
+       When a line ending is defined as a single character, dot never  matches
+       that  character; when the two-character sequence CRLF is used, dot does
+       not match CR if it is immediately followed  by  LF,  but  otherwise  it
+       matches  all characters (including isolated CRs and LFs). When any Uni-
+       code line endings are being recognized, dot does not match CR or LF  or
+       any of the other line ending characters.
+
+       The  behaviour  of  dot  with regard to newlines can be changed. If the
+       PCRE_DOTALL option is set, a dot matches  any  one  character,  without
+       exception. If the two-character sequence CRLF is present in the subject
+       string, it takes two dots to match it.
+
+       The handling of dot is entirely independent of the handling of  circum-
+       flex  and  dollar,  the  only relationship being that they both involve
+       newlines. Dot has no special meaning in a character class.
+
+       The escape sequence \N behaves like  a  dot,  except  that  it  is  not
+       affected  by  the  PCRE_DOTALL  option.  In other words, it matches any
+       character except one that signifies the end of a line. Perl  also  uses
+       \N to match characters by name; PCRE does not support this.
+
+
+MATCHING A SINGLE DATA UNIT
+
+       Outside  a character class, the escape sequence \C matches any one data
+       unit, whether or not a UTF mode is set. In the 8-bit library, one  data
+       unit  is  one  byte;  in the 16-bit library it is a 16-bit unit; in the
+       32-bit library it is a 32-bit unit. Unlike a  dot,  \C  always  matches
+       line-ending  characters.  The  feature  is provided in Perl in order to
+       match individual bytes in UTF-8 mode, but it is unclear how it can use-
+       fully  be  used.  Because  \C breaks up characters into individual data
+       units, matching one unit with \C in a UTF mode means that the  rest  of
+       the string may start with a malformed UTF character. This has undefined
+       results, because PCRE assumes that it is dealing with valid UTF strings
+       (and  by  default  it checks this at the start of processing unless the
+       PCRE_NO_UTF8_CHECK, PCRE_NO_UTF16_CHECK or  PCRE_NO_UTF32_CHECK  option
+       is used).
+
+       PCRE  does  not  allow \C to appear in lookbehind assertions (described
+       below) in a UTF mode, because this would make it impossible  to  calcu-
+       late the length of the lookbehind.
+
+       In general, the \C escape sequence is best avoided. However, one way of
+       using it that avoids the problem of malformed UTF characters is to  use
+       a  lookahead to check the length of the next character, as in this pat-
+       tern, which could be used with a UTF-8 string (ignore white  space  and
+       line breaks):
+
+         (?| (?=[\x00-\x7f])(\C) |
+             (?=[\x80-\x{7ff}])(\C)(\C) |
+             (?=[\x{800}-\x{ffff}])(\C)(\C)(\C) |
+             (?=[\x{10000}-\x{1fffff}])(\C)(\C)(\C)(\C))
+
+       A  group  that starts with (?| resets the capturing parentheses numbers
+       in each alternative (see "Duplicate  Subpattern  Numbers"  below).  The
+       assertions  at  the start of each branch check the next UTF-8 character
+       for values whose encoding uses 1, 2, 3, or 4 bytes,  respectively.  The
+       character's  individual bytes are then captured by the appropriate num-
+       ber of groups.
+
+
+SQUARE BRACKETS AND CHARACTER CLASSES
+
+       An opening square bracket introduces a character class, terminated by a
+       closing square bracket. A closing square bracket on its own is not spe-
+       cial by default.  However, if the PCRE_JAVASCRIPT_COMPAT option is set,
+       a lone closing square bracket causes a compile-time error. If a closing
+       square bracket is required as a member of the class, it should  be  the
+       first  data  character  in  the  class (after an initial circumflex, if
+       present) or escaped with a backslash.
+
+       A character class matches a single character in the subject. In  a  UTF
+       mode,  the  character  may  be  more than one data unit long. A matched
+       character must be in the set of characters defined by the class, unless
+       the  first  character in the class definition is a circumflex, in which
+       case the subject character must not be in the set defined by the class.
+       If  a  circumflex is actually required as a member of the class, ensure
+       it is not the first character, or escape it with a backslash.
+
+       For example, the character class [aeiou] matches any lower case  vowel,
+       while  [^aeiou]  matches  any character that is not a lower case vowel.
+       Note that a circumflex is just a convenient notation for specifying the
+       characters  that  are in the class by enumerating those that are not. A
+       class that starts with a circumflex is not an assertion; it still  con-
+       sumes  a  character  from the subject string, and therefore it fails if
+       the current pointer is at the end of the string.
+
+       In UTF-8 (UTF-16, UTF-32) mode, characters with values greater than 255
+       (0xffff)  can be included in a class as a literal string of data units,
+       or by using the \x{ escaping mechanism.
+
+       When caseless matching is set, any letters in a  class  represent  both
+       their  upper  case  and lower case versions, so for example, a caseless
+       [aeiou] matches "A" as well as "a", and a caseless  [^aeiou]  does  not
+       match  "A", whereas a caseful version would. In a UTF mode, PCRE always
+       understands the concept of case for characters whose  values  are  less
+       than  128, so caseless matching is always possible. For characters with
+       higher values, the concept of case is supported  if  PCRE  is  compiled
+       with  Unicode  property support, but not otherwise.  If you want to use
+       caseless matching in a UTF mode for characters 128 and above, you  must
+       ensure  that  PCRE is compiled with Unicode property support as well as
+       with UTF support.
+
+       Characters that might indicate line breaks are  never  treated  in  any
+       special  way  when  matching  character  classes,  whatever line-ending
+       sequence is in  use,  and  whatever  setting  of  the  PCRE_DOTALL  and
+       PCRE_MULTILINE options is used. A class such as [^a] always matches one
+       of these characters.
+
+       The minus (hyphen) character can be used to specify a range of  charac-
+       ters  in  a  character  class.  For  example,  [d-m] matches any letter
+       between d and m, inclusive. If a  minus  character  is  required  in  a
+       class,  it  must  be  escaped  with a backslash or appear in a position
+       where it cannot be interpreted as indicating a range, typically as  the
+       first or last character in the class, or immediately after a range. For
+       example, [b-d-z] matches letters in the range b to d, a hyphen  charac-
+       ter, or z.
+
+       It is not possible to have the literal character "]" as the end charac-
+       ter of a range. A pattern such as [W-]46] is interpreted as a class  of
+       two  characters ("W" and "-") followed by a literal string "46]", so it
+       would match "W46]" or "-46]". However, if the "]"  is  escaped  with  a
+       backslash  it is interpreted as the end of range, so [W-\]46] is inter-
+       preted as a class containing a range followed by two other  characters.
+       The  octal or hexadecimal representation of "]" can also be used to end
+       a range.
+
+       An error is generated if a POSIX character  class  (see  below)  or  an
+       escape  sequence other than one that defines a single character appears
+       at a point where a range ending character  is  expected.  For  example,
+       [z-\xff] is valid, but [A-\d] and [A-[:digit:]] are not.
+
+       Ranges  operate in the collating sequence of character values. They can
+       also  be  used  for  characters  specified  numerically,  for   example
+       [\000-\037].  Ranges  can include any characters that are valid for the
+       current mode.
+
+       If a range that includes letters is used when caseless matching is set,
+       it matches the letters in either case. For example, [W-c] is equivalent
+       to [][\\^_`wxyzabc], matched caselessly, and  in  a  non-UTF  mode,  if
+       character  tables  for  a French locale are in use, [\xc8-\xcb] matches
+       accented E characters in both cases. In UTF modes,  PCRE  supports  the
+       concept  of  case for characters with values greater than 128 only when
+       it is compiled with Unicode property support.
+
+       The character escape sequences \d, \D, \h, \H, \p, \P, \s, \S, \v,  \V,
+       \w, and \W may appear in a character class, and add the characters that
+       they match to the class. For example, [\dABCDEF] matches any  hexadeci-
+       mal  digit.  In  UTF modes, the PCRE_UCP option affects the meanings of
+       \d, \s, \w and their upper case partners, just as  it  does  when  they
+       appear  outside a character class, as described in the section entitled
+       "Generic character types" above. The escape sequence \b has a different
+       meaning  inside  a character class; it matches the backspace character.
+       The sequences \B, \N, \R, and \X are not  special  inside  a  character
+       class.  Like  any other unrecognized escape sequences, they are treated
+       as the literal characters "B", "N", "R", and "X" by default, but  cause
+       an error if the PCRE_EXTRA option is set.
+
+       A  circumflex  can  conveniently  be used with the upper case character
+       types to specify a more restricted set of characters than the  matching
+       lower  case  type.  For example, the class [^\W_] matches any letter or
+       digit, but not underscore, whereas [\w] includes underscore. A positive
+       character class should be read as "something OR something OR ..." and a
+       negative class as "NOT something AND NOT something AND NOT ...".
+
+       The only metacharacters that are recognized in  character  classes  are
+       backslash,  hyphen  (only  where  it can be interpreted as specifying a
+       range), circumflex (only at the start), opening  square  bracket  (only
+       when  it can be interpreted as introducing a POSIX class name, or for a
+       special compatibility feature - see the next  two  sections),  and  the
+       terminating  closing  square  bracket.  However,  escaping  other  non-
+       alphanumeric characters does no harm.
+
+
+POSIX CHARACTER CLASSES
+
+       Perl supports the POSIX notation for character classes. This uses names
+       enclosed  by  [: and :] within the enclosing square brackets. PCRE also
+       supports this notation. For example,
+
+         [01[:alpha:]%]
+
+       matches "0", "1", any alphabetic character, or "%". The supported class
+       names are:
+
+         alnum    letters and digits
+         alpha    letters
+         ascii    character codes 0 - 127
+         blank    space or tab only
+         cntrl    control characters
+         digit    decimal digits (same as \d)
+         graph    printing characters, excluding space
+         lower    lower case letters
+         print    printing characters, including space
+         punct    printing characters, excluding letters and digits and space
+         space    white space (the same as \s from PCRE 8.34)
+         upper    upper case letters
+         word     "word" characters (same as \w)
+         xdigit   hexadecimal digits
+
+       The  default  "space" characters are HT (9), LF (10), VT (11), FF (12),
+       CR (13), and space (32). If locale-specific matching is  taking  place,
+       the  list  of  space characters may be different; there may be fewer or
+       more of them. "Space" used to be different to \s, which did not include
+       VT, for Perl compatibility.  However, Perl changed at release 5.18, and
+       PCRE followed at release 8.34.  "Space" and \s now match the  same  set
+       of characters.
+
+       The  name  "word"  is  a Perl extension, and "blank" is a GNU extension
+       from Perl 5.8. Another Perl extension is negation, which  is  indicated
+       by a ^ character after the colon. For example,
+
+         [12[:^digit:]]
+
+       matches  "1", "2", or any non-digit. PCRE (and Perl) also recognize the
+       POSIX syntax [.ch.] and [=ch=] where "ch" is a "collating element", but
+       these are not supported, and an error is given if they are encountered.
+
+       By default, characters with values greater than 128 do not match any of
+       the POSIX character classes. However, if the PCRE_UCP option is  passed
+       to  pcre_compile(),  some  of  the  classes are changed so that Unicode
+       character properties are used. This is achieved  by  replacing  certain
+       POSIX classes by other sequences, as follows:
+
+         [:alnum:]  becomes  \p{Xan}
+         [:alpha:]  becomes  \p{L}
+         [:blank:]  becomes  \h
+         [:digit:]  becomes  \p{Nd}
+         [:lower:]  becomes  \p{Ll}
+         [:space:]  becomes  \p{Xps}
+         [:upper:]  becomes  \p{Lu}
+         [:word:]   becomes  \p{Xwd}
+
+       Negated  versions, such as [:^alpha:] use \P instead of \p. Three other
+       POSIX classes are handled specially in UCP mode:
+
+       [:graph:] This matches characters that have glyphs that mark  the  page
+                 when printed. In Unicode property terms, it matches all char-
+                 acters with the L, M, N, P, S, or Cf properties, except for:
+
+                   U+061C           Arabic Letter Mark
+                   U+180E           Mongolian Vowel Separator
+                   U+2066 - U+2069  Various "isolate"s
+
+
+       [:print:] This matches the same  characters  as  [:graph:]  plus  space
+                 characters  that  are  not controls, that is, characters with
+                 the Zs property.
+
+       [:punct:] This matches all characters that have the Unicode P (punctua-
+                 tion)  property,  plus those characters whose code points are
+                 less than 128 that have the S (Symbol) property.
+
+       The other POSIX classes are unchanged, and match only  characters  with
+       code points less than 128.
+
+
+COMPATIBILITY FEATURE FOR WORD BOUNDARIES
+
+       In  the POSIX.2 compliant library that was included in 4.4BSD Unix, the
+       ugly syntax [[:<:]] and [[:>:]] is used for matching  "start  of  word"
+       and "end of word". PCRE treats these items as follows:
+
+         [[:<:]]  is converted to  \b(?=\w)
+         [[:>:]]  is converted to  \b(?<=\w)
+
+       Only these exact character sequences are recognized. A sequence such as
+       [a[:<:]b] provokes error for an unrecognized  POSIX  class  name.  This
+       support  is not compatible with Perl. It is provided to help migrations
+       from other environments, and is best not used in any new patterns. Note
+       that  \b matches at the start and the end of a word (see "Simple asser-
+       tions" above), and in a Perl-style pattern the preceding  or  following
+       character  normally  shows  which  is  wanted, without the need for the
+       assertions that are used above in order to give exactly the  POSIX  be-
+       haviour.
+
+
+VERTICAL BAR
+
+       Vertical  bar characters are used to separate alternative patterns. For
+       example, the pattern
+
+         gilbert|sullivan
+
+       matches either "gilbert" or "sullivan". Any number of alternatives  may
+       appear,  and  an  empty  alternative  is  permitted (matching the empty
+       string). The matching process tries each alternative in turn, from left
+       to  right, and the first one that succeeds is used. If the alternatives
+       are within a subpattern (defined below), "succeeds" means matching  the
+       rest of the main pattern as well as the alternative in the subpattern.
+
+
+INTERNAL OPTION SETTING
+
+       The  settings  of  the  PCRE_CASELESS, PCRE_MULTILINE, PCRE_DOTALL, and
+       PCRE_EXTENDED options (which are Perl-compatible) can be  changed  from
+       within  the  pattern  by  a  sequence  of  Perl option letters enclosed
+       between "(?" and ")".  The option letters are
+
+         i  for PCRE_CASELESS
+         m  for PCRE_MULTILINE
+         s  for PCRE_DOTALL
+         x  for PCRE_EXTENDED
+
+       For example, (?im) sets caseless, multiline matching. It is also possi-
+       ble to unset these options by preceding the letter with a hyphen, and a
+       combined setting and unsetting such as (?im-sx), which sets  PCRE_CASE-
+       LESS  and PCRE_MULTILINE while unsetting PCRE_DOTALL and PCRE_EXTENDED,
+       is also permitted. If a  letter  appears  both  before  and  after  the
+       hyphen, the option is unset.
+
+       The  PCRE-specific options PCRE_DUPNAMES, PCRE_UNGREEDY, and PCRE_EXTRA
+       can be changed in the same way as the Perl-compatible options by  using
+       the characters J, U and X respectively.
+
+       When  one  of  these  option  changes occurs at top level (that is, not
+       inside subpattern parentheses), the change applies to the remainder  of
+       the pattern that follows. If the change is placed right at the start of
+       a pattern, PCRE extracts it into the global options (and it will there-
+       fore show up in data extracted by the pcre_fullinfo() function).
+
+       An  option  change  within a subpattern (see below for a description of
+       subpatterns) affects only that part of the subpattern that follows  it,
+       so
+
+         (a(?i)b)c
+
+       matches abc and aBc and no other strings (assuming PCRE_CASELESS is not
+       used).  By this means, options can be made to have  different  settings
+       in  different parts of the pattern. Any changes made in one alternative
+       do carry on into subsequent branches within the  same  subpattern.  For
+       example,
+
+         (a(?i)b|c)
+
+       matches  "ab",  "aB",  "c",  and "C", even though when matching "C" the
+       first branch is abandoned before the option setting.  This  is  because
+       the  effects  of option settings happen at compile time. There would be
+       some very weird behaviour otherwise.
+
+       Note: There are other PCRE-specific options that  can  be  set  by  the
+       application  when  the  compiling  or matching functions are called. In
+       some cases the pattern can contain special leading  sequences  such  as
+       (*CRLF)  to  override  what  the  application  has set or what has been
+       defaulted.  Details  are  given  in  the  section   entitled   "Newline
+       sequences"  above.  There  are also the (*UTF8), (*UTF16),(*UTF32), and
+       (*UCP) leading sequences that can be used to set UTF and Unicode  prop-
+       erty  modes;  they are equivalent to setting the PCRE_UTF8, PCRE_UTF16,
+       PCRE_UTF32 and the PCRE_UCP options, respectively. The (*UTF)  sequence
+       is  a  generic version that can be used with any of the libraries. How-
+       ever, the application can set the PCRE_NEVER_UTF  option,  which  locks
+       out the use of the (*UTF) sequences.
+
+
+SUBPATTERNS
+
+       Subpatterns are delimited by parentheses (round brackets), which can be
+       nested.  Turning part of a pattern into a subpattern does two things:
+
+       1. It localizes a set of alternatives. For example, the pattern
+
+         cat(aract|erpillar|)
+
+       matches "cataract", "caterpillar", or "cat". Without  the  parentheses,
+       it would match "cataract", "erpillar" or an empty string.
+
+       2.  It  sets  up  the  subpattern as a capturing subpattern. This means
+       that, when the whole pattern  matches,  that  portion  of  the  subject
+       string that matched the subpattern is passed back to the caller via the
+       ovector argument of the matching function. (This applies  only  to  the
+       traditional  matching functions; the DFA matching functions do not sup-
+       port capturing.)
+
+       Opening parentheses are counted from left to right (starting from 1) to
+       obtain  numbers  for  the  capturing  subpatterns.  For example, if the
+       string "the red king" is matched against the pattern
+
+         the ((red|white) (king|queen))
+
+       the captured substrings are "red king", "red", and "king", and are num-
+       bered 1, 2, and 3, respectively.
+
+       The  fact  that  plain  parentheses  fulfil two functions is not always
+       helpful.  There are often times when a grouping subpattern is  required
+       without  a capturing requirement. If an opening parenthesis is followed
+       by a question mark and a colon, the subpattern does not do any  captur-
+       ing,  and  is  not  counted when computing the number of any subsequent
+       capturing subpatterns. For example, if the string "the white queen"  is
+       matched against the pattern
+
+         the ((?:red|white) (king|queen))
+
+       the captured substrings are "white queen" and "queen", and are numbered
+       1 and 2. The maximum number of capturing subpatterns is 65535.
+
+       As a convenient shorthand, if any option settings are required  at  the
+       start  of  a  non-capturing  subpattern,  the option letters may appear
+       between the "?" and the ":". Thus the two patterns
+
+         (?i:saturday|sunday)
+         (?:(?i)saturday|sunday)
+
+       match exactly the same set of strings. Because alternative branches are
+       tried  from  left  to right, and options are not reset until the end of
+       the subpattern is reached, an option setting in one branch does  affect
+       subsequent  branches,  so  the above patterns match "SUNDAY" as well as
+       "Saturday".
+
+
+DUPLICATE SUBPATTERN NUMBERS
+
+       Perl 5.10 introduced a feature whereby each alternative in a subpattern
+       uses  the same numbers for its capturing parentheses. Such a subpattern
+       starts with (?| and is itself a non-capturing subpattern. For  example,
+       consider this pattern:
+
+         (?|(Sat)ur|(Sun))day
+
+       Because  the two alternatives are inside a (?| group, both sets of cap-
+       turing parentheses are numbered one. Thus, when  the  pattern  matches,
+       you  can  look  at captured substring number one, whichever alternative
+       matched. This construct is useful when you want to  capture  part,  but
+       not all, of one of a number of alternatives. Inside a (?| group, paren-
+       theses are numbered as usual, but the number is reset at the  start  of
+       each  branch.  The numbers of any capturing parentheses that follow the
+       subpattern start after the highest number used in any branch. The  fol-
+       lowing example is taken from the Perl documentation. The numbers under-
+       neath show in which buffer the captured content will be stored.
+
+         # before  ---------------branch-reset----------- after
+         / ( a )  (?| x ( y ) z | (p (q) r) | (t) u (v) ) ( z ) /x
+         # 1            2         2  3        2     3     4
+
+       A back reference to a numbered subpattern uses the  most  recent  value
+       that  is  set  for that number by any subpattern. The following pattern
+       matches "abcabc" or "defdef":
+
+         /(?|(abc)|(def))\1/
+
+       In contrast, a subroutine call to a numbered subpattern  always  refers
+       to  the  first  one in the pattern with the given number. The following
+       pattern matches "abcabc" or "defabc":
+
+         /(?|(abc)|(def))(?1)/
+
+       If a condition test for a subpattern's having matched refers to a  non-
+       unique  number, the test is true if any of the subpatterns of that num-
+       ber have matched.
+
+       An alternative approach to using this "branch reset" feature is to  use
+       duplicate named subpatterns, as described in the next section.
+
+
+NAMED SUBPATTERNS
+
+       Identifying  capturing  parentheses  by number is simple, but it can be
+       very hard to keep track of the numbers in complicated  regular  expres-
+       sions.  Furthermore,  if  an  expression  is  modified, the numbers may
+       change. To help with this difficulty, PCRE supports the naming of  sub-
+       patterns. This feature was not added to Perl until release 5.10. Python
+       had the feature earlier, and PCRE introduced it at release  4.0,  using
+       the  Python syntax. PCRE now supports both the Perl and the Python syn-
+       tax. Perl allows identically numbered  subpatterns  to  have  different
+       names, but PCRE does not.
+
+       In  PCRE,  a subpattern can be named in one of three ways: (?<name>...)
+       or (?'name'...) as in Perl, or (?P<name>...) as in  Python.  References
+       to  capturing parentheses from other parts of the pattern, such as back
+       references, recursion, and conditions, can be made by name as  well  as
+       by number.
+
+       Names  consist of up to 32 alphanumeric characters and underscores, but
+       must start with a non-digit.  Named  capturing  parentheses  are  still
+       allocated  numbers  as  well as names, exactly as if the names were not
+       present. The PCRE API provides function calls for extracting the  name-
+       to-number  translation  table  from a compiled pattern. There is also a
+       convenience function for extracting a captured substring by name.
+
+       By default, a name must be unique within a pattern, but it is  possible
+       to relax this constraint by setting the PCRE_DUPNAMES option at compile
+       time. (Duplicate names are also always permitted for  subpatterns  with
+       the  same  number, set up as described in the previous section.) Dupli-
+       cate names can be useful for patterns where only one  instance  of  the
+       named  parentheses  can  match. Suppose you want to match the name of a
+       weekday, either as a 3-letter abbreviation or as the full name, and  in
+       both cases you want to extract the abbreviation. This pattern (ignoring
+       the line breaks) does the job:
+
+         (?<DN>Mon|Fri|Sun)(?:day)?|
+         (?<DN>Tue)(?:sday)?|
+         (?<DN>Wed)(?:nesday)?|
+         (?<DN>Thu)(?:rsday)?|
+         (?<DN>Sat)(?:urday)?
+
+       There are five capturing substrings, but only one is ever set  after  a
+       match.  (An alternative way of solving this problem is to use a "branch
+       reset" subpattern, as described in the previous section.)
+
+       The convenience function for extracting the data by  name  returns  the
+       substring  for  the first (and in this example, the only) subpattern of
+       that name that matched. This saves searching  to  find  which  numbered
+       subpattern it was.
+
+       If  you  make  a  back  reference to a non-unique named subpattern from
+       elsewhere in the pattern, the subpatterns to which the name refers  are
+       checked  in  the order in which they appear in the overall pattern. The
+       first one that is set is used for the reference. For example, this pat-
+       tern matches both "foofoo" and "barbar" but not "foobar" or "barfoo":
+
+         (?:(?<n>foo)|(?<n>bar))\k<n>
+
+
+       If you make a subroutine call to a non-unique named subpattern, the one
+       that corresponds to the first occurrence of the name is  used.  In  the
+       absence of duplicate numbers (see the previous section) this is the one
+       with the lowest number.
+
+       If you use a named reference in a condition test (see the section about
+       conditions below), either to check whether a subpattern has matched, or
+       to check for recursion, all subpatterns with the same name are  tested.
+       If  the condition is true for any one of them, the overall condition is
+       true. This is the same behaviour as  testing  by  number.  For  further
+       details  of  the  interfaces  for  handling  named subpatterns, see the
+       pcreapi documentation.
+
+       Warning: You cannot use different names to distinguish between two sub-
+       patterns  with  the same number because PCRE uses only the numbers when
+       matching. For this reason, an error is given at compile time if differ-
+       ent  names  are given to subpatterns with the same number. However, you
+       can always give the same name to subpatterns with the same number, even
+       when PCRE_DUPNAMES is not set.
+
+
+REPETITION
+
+       Repetition  is  specified  by  quantifiers, which can follow any of the
+       following items:
+
+         a literal data character
+         the dot metacharacter
+         the \C escape sequence
+         the \X escape sequence
+         the \R escape sequence
+         an escape such as \d or \pL that matches a single character
+         a character class
+         a back reference (see next section)
+         a parenthesized subpattern (including assertions)
+         a subroutine call to a subpattern (recursive or otherwise)
+
+       The general repetition quantifier specifies a minimum and maximum  num-
+       ber  of  permitted matches, by giving the two numbers in curly brackets
+       (braces), separated by a comma. The numbers must be  less  than  65536,
+       and the first must be less than or equal to the second. For example:
+
+         z{2,4}
+
+       matches  "zz",  "zzz",  or  "zzzz". A closing brace on its own is not a
+       special character. If the second number is omitted, but  the  comma  is
+       present,  there  is  no upper limit; if the second number and the comma
+       are both omitted, the quantifier specifies an exact number of  required
+       matches. Thus
+
+         [aeiou]{3,}
+
+       matches at least 3 successive vowels, but may match many more, while
+
+         \d{8}
+
+       matches  exactly  8  digits. An opening curly bracket that appears in a
+       position where a quantifier is not allowed, or one that does not  match
+       the  syntax of a quantifier, is taken as a literal character. For exam-
+       ple, {,6} is not a quantifier, but a literal string of four characters.
+
+       In UTF modes, quantifiers apply to characters rather than to individual
+       data  units. Thus, for example, \x{100}{2} matches two characters, each
+       of which is represented by a two-byte sequence in a UTF-8 string. Simi-
+       larly,  \X{3} matches three Unicode extended grapheme clusters, each of
+       which may be several data units long (and  they  may  be  of  different
+       lengths).
+
+       The quantifier {0} is permitted, causing the expression to behave as if
+       the previous item and the quantifier were not present. This may be use-
+       ful  for  subpatterns that are referenced as subroutines from elsewhere
+       in the pattern (but see also the section entitled "Defining subpatterns
+       for  use  by  reference only" below). Items other than subpatterns that
+       have a {0} quantifier are omitted from the compiled pattern.
+
+       For convenience, the three most common quantifiers have  single-charac-
+       ter abbreviations:
+
+         *    is equivalent to {0,}
+         +    is equivalent to {1,}
+         ?    is equivalent to {0,1}
+
+       It  is  possible  to construct infinite loops by following a subpattern
+       that can match no characters with a quantifier that has no upper limit,
+       for example:
+
+         (a?)*
+
+       Earlier versions of Perl and PCRE used to give an error at compile time
+       for such patterns. However, because there are cases where this  can  be
+       useful,  such  patterns  are now accepted, but if any repetition of the
+       subpattern does in fact match no characters, the loop is forcibly  bro-
+       ken.
+
+       By  default,  the quantifiers are "greedy", that is, they match as much
+       as possible (up to the maximum  number  of  permitted  times),  without
+       causing  the  rest of the pattern to fail. The classic example of where
+       this gives problems is in trying to match comments in C programs. These
+       appear  between  /*  and  */ and within the comment, individual * and /
+       characters may appear. An attempt to match C comments by  applying  the
+       pattern
+
+         /\*.*\*/
+
+       to the string
+
+         /* first comment */  not comment  /* second comment */
+
+       fails,  because it matches the entire string owing to the greediness of
+       the .*  item.
+
+       However, if a quantifier is followed by a question mark, it  ceases  to
+       be greedy, and instead matches the minimum number of times possible, so
+       the pattern
+
+         /\*.*?\*/
+
+       does the right thing with the C comments. The meaning  of  the  various
+       quantifiers  is  not  otherwise  changed,  just the preferred number of
+       matches.  Do not confuse this use of question mark with its  use  as  a
+       quantifier  in its own right. Because it has two uses, it can sometimes
+       appear doubled, as in
+
+         \d??\d
+
+       which matches one digit by preference, but can match two if that is the
+       only way the rest of the pattern matches.
+
+       If  the PCRE_UNGREEDY option is set (an option that is not available in
+       Perl), the quantifiers are not greedy by default, but  individual  ones
+       can  be  made  greedy  by following them with a question mark. In other
+       words, it inverts the default behaviour.
+
+       When a parenthesized subpattern is quantified  with  a  minimum  repeat
+       count  that is greater than 1 or with a limited maximum, more memory is
+       required for the compiled pattern, in proportion to  the  size  of  the
+       minimum or maximum.
+
+       If a pattern starts with .* or .{0,} and the PCRE_DOTALL option (equiv-
+       alent to Perl's /s) is set, thus allowing the dot  to  match  newlines,
+       the  pattern  is  implicitly anchored, because whatever follows will be
+       tried against every character position in the subject string, so  there
+       is  no  point  in  retrying the overall match at any position after the
+       first. PCRE normally treats such a pattern as though it  were  preceded
+       by \A.
+
+       In  cases  where  it  is known that the subject string contains no new-
+       lines, it is worth setting PCRE_DOTALL in order to  obtain  this  opti-
+       mization, or alternatively using ^ to indicate anchoring explicitly.
+
+       However,  there  are  some cases where the optimization cannot be used.
+       When .*  is inside capturing parentheses that are the subject of a back
+       reference elsewhere in the pattern, a match at the start may fail where
+       a later one succeeds. Consider, for example:
+
+         (.*)abc\1
+
+       If the subject is "xyz123abc123" the match point is the fourth  charac-
+       ter. For this reason, such a pattern is not implicitly anchored.
+
+       Another  case where implicit anchoring is not applied is when the lead-
+       ing .* is inside an atomic group. Once again, a match at the start  may
+       fail where a later one succeeds. Consider this pattern:
+
+         (?>.*?a)b
+
+       It  matches "ab" in the subject "aab". The use of the backtracking con-
+       trol verbs (*PRUNE) and (*SKIP) also disable this optimization.
+
+       When a capturing subpattern is repeated, the value captured is the sub-
+       string that matched the final iteration. For example, after
+
+         (tweedle[dume]{3}\s*)+
+
+       has matched "tweedledum tweedledee" the value of the captured substring
+       is "tweedledee". However, if there are  nested  capturing  subpatterns,
+       the  corresponding captured values may have been set in previous itera-
+       tions. For example, after
+
+         /(a|(b))+/
+
+       matches "aba" the value of the second captured substring is "b".
+
+
+ATOMIC GROUPING AND POSSESSIVE QUANTIFIERS
+
+       With both maximizing ("greedy") and minimizing ("ungreedy"  or  "lazy")
+       repetition,  failure  of what follows normally causes the repeated item
+       to be re-evaluated to see if a different number of repeats  allows  the
+       rest  of  the pattern to match. Sometimes it is useful to prevent this,
+       either to change the nature of the match, or to cause it  fail  earlier
+       than  it otherwise might, when the author of the pattern knows there is
+       no point in carrying on.
+
+       Consider, for example, the pattern \d+foo when applied to  the  subject
+       line
+
+         123456bar
+
+       After matching all 6 digits and then failing to match "foo", the normal
+       action of the matcher is to try again with only 5 digits  matching  the
+       \d+  item,  and  then  with  4,  and  so on, before ultimately failing.
+       "Atomic grouping" (a term taken from Jeffrey  Friedl's  book)  provides
+       the  means for specifying that once a subpattern has matched, it is not
+       to be re-evaluated in this way.
+
+       If we use atomic grouping for the previous example, the  matcher  gives
+       up  immediately  on failing to match "foo" the first time. The notation
+       is a kind of special parenthesis, starting with (?> as in this example:
+
+         (?>\d+)foo
+
+       This kind of parenthesis "locks up" the  part of the  pattern  it  con-
+       tains  once  it  has matched, and a failure further into the pattern is
+       prevented from backtracking into it. Backtracking past it  to  previous
+       items, however, works as normal.
+
+       An  alternative  description  is that a subpattern of this type matches
+       the string of characters that an  identical  standalone  pattern  would
+       match, if anchored at the current point in the subject string.
+
+       Atomic grouping subpatterns are not capturing subpatterns. Simple cases
+       such as the above example can be thought of as a maximizing repeat that
+       must  swallow  everything  it can. So, while both \d+ and \d+? are pre-
+       pared to adjust the number of digits they match in order  to  make  the
+       rest of the pattern match, (?>\d+) can only match an entire sequence of
+       digits.
+
+       Atomic groups in general can of course contain arbitrarily  complicated
+       subpatterns,  and  can  be  nested. However, when the subpattern for an
+       atomic group is just a single repeated item, as in the example above, a
+       simpler  notation,  called  a "possessive quantifier" can be used. This
+       consists of an additional + character  following  a  quantifier.  Using
+       this notation, the previous example can be rewritten as
+
+         \d++foo
+
+       Note that a possessive quantifier can be used with an entire group, for
+       example:
+
+         (abc|xyz){2,3}+
+
+       Possessive  quantifiers  are  always  greedy;  the   setting   of   the
+       PCRE_UNGREEDY option is ignored. They are a convenient notation for the
+       simpler forms of atomic group. However, there is no difference  in  the
+       meaning  of  a  possessive  quantifier and the equivalent atomic group,
+       though there may be a performance  difference;  possessive  quantifiers
+       should be slightly faster.
+
+       The  possessive  quantifier syntax is an extension to the Perl 5.8 syn-
+       tax.  Jeffrey Friedl originated the idea (and the name)  in  the  first
+       edition of his book. Mike McCloskey liked it, so implemented it when he
+       built Sun's Java package, and PCRE copied it from there. It  ultimately
+       found its way into Perl at release 5.10.
+
+       PCRE has an optimization that automatically "possessifies" certain sim-
+       ple pattern constructs. For example, the sequence  A+B  is  treated  as
+       A++B  because  there is no point in backtracking into a sequence of A's
+       when B must follow.
+
+       When a pattern contains an unlimited repeat inside  a  subpattern  that
+       can  itself  be  repeated  an  unlimited number of times, the use of an
+       atomic group is the only way to avoid some  failing  matches  taking  a
+       very long time indeed. The pattern
+
+         (\D+|<\d+>)*[!?]
+
+       matches  an  unlimited number of substrings that either consist of non-
+       digits, or digits enclosed in <>, followed by either ! or  ?.  When  it
+       matches, it runs quickly. However, if it is applied to
+
+         aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+
+       it  takes  a  long  time  before reporting failure. This is because the
+       string can be divided between the internal \D+ repeat and the  external
+       *  repeat  in  a  large  number of ways, and all have to be tried. (The
+       example uses [!?] rather than a single character at  the  end,  because
+       both  PCRE  and  Perl have an optimization that allows for fast failure
+       when a single character is used. They remember the last single  charac-
+       ter  that  is required for a match, and fail early if it is not present
+       in the string.) If the pattern is changed so that  it  uses  an  atomic
+       group, like this:
+
+         ((?>\D+)|<\d+>)*[!?]
+
+       sequences of non-digits cannot be broken, and failure happens quickly.
+
+
+BACK REFERENCES
+
+       Outside a character class, a backslash followed by a digit greater than
+       0 (and possibly further digits) is a back reference to a capturing sub-
+       pattern  earlier  (that is, to its left) in the pattern, provided there
+       have been that many previous capturing left parentheses.
+
+       However, if the decimal number following the backslash is less than 10,
+       it  is  always  taken  as a back reference, and causes an error only if
+       there are not that many capturing left parentheses in the  entire  pat-
+       tern.  In  other words, the parentheses that are referenced need not be
+       to the left of the reference for numbers less than 10. A "forward  back
+       reference"  of  this  type can make sense when a repetition is involved
+       and the subpattern to the right has participated in an  earlier  itera-
+       tion.
+
+       It  is  not  possible to have a numerical "forward back reference" to a
+       subpattern whose number is 10 or  more  using  this  syntax  because  a
+       sequence  such  as  \50 is interpreted as a character defined in octal.
+       See the subsection entitled "Non-printing characters" above for further
+       details  of  the  handling of digits following a backslash. There is no
+       such problem when named parentheses are used. A back reference  to  any
+       subpattern is possible using named parentheses (see below).
+
+       Another  way  of  avoiding  the ambiguity inherent in the use of digits
+       following a backslash is to use the \g  escape  sequence.  This  escape
+       must be followed by an unsigned number or a negative number, optionally
+       enclosed in braces. These examples are all identical:
+
+         (ring), \1
+         (ring), \g1
+         (ring), \g{1}
+
+       An unsigned number specifies an absolute reference without the  ambigu-
+       ity that is present in the older syntax. It is also useful when literal
+       digits follow the reference. A negative number is a relative reference.
+       Consider this example:
+
+         (abc(def)ghi)\g{-1}
+
+       The sequence \g{-1} is a reference to the most recently started captur-
+       ing subpattern before \g, that is, is it equivalent to \2 in this exam-
+       ple.   Similarly, \g{-2} would be equivalent to \1. The use of relative
+       references can be helpful in long patterns, and also in  patterns  that
+       are  created  by  joining  together  fragments  that contain references
+       within themselves.
+
+       A back reference matches whatever actually matched the  capturing  sub-
+       pattern  in  the  current subject string, rather than anything matching
+       the subpattern itself (see "Subpatterns as subroutines" below for a way
+       of doing that). So the pattern
+
+         (sens|respons)e and \1ibility
+
+       matches  "sense and sensibility" and "response and responsibility", but
+       not "sense and responsibility". If caseful matching is in force at  the
+       time  of the back reference, the case of letters is relevant. For exam-
+       ple,
+
+         ((?i)rah)\s+\1
+
+       matches "rah rah" and "RAH RAH", but not "RAH  rah",  even  though  the
+       original capturing subpattern is matched caselessly.
+
+       There  are  several  different ways of writing back references to named
+       subpatterns. The .NET syntax \k{name} and the Perl syntax  \k<name>  or
+       \k'name'  are supported, as is the Python syntax (?P=name). Perl 5.10's
+       unified back reference syntax, in which \g can be used for both numeric
+       and  named  references,  is  also supported. We could rewrite the above
+       example in any of the following ways:
+
+         (?<p1>(?i)rah)\s+\k<p1>
+         (?'p1'(?i)rah)\s+\k{p1}
+         (?P<p1>(?i)rah)\s+(?P=p1)
+         (?<p1>(?i)rah)\s+\g{p1}
+
+       A subpattern that is referenced by  name  may  appear  in  the  pattern
+       before or after the reference.
+
+       There  may be more than one back reference to the same subpattern. If a
+       subpattern has not actually been used in a particular match,  any  back
+       references to it always fail by default. For example, the pattern
+
+         (a|(bc))\2
+
+       always  fails  if  it starts to match "a" rather than "bc". However, if
+       the PCRE_JAVASCRIPT_COMPAT option is set at compile time, a back refer-
+       ence to an unset value matches an empty string.
+
+       Because  there may be many capturing parentheses in a pattern, all dig-
+       its following a backslash are taken as part of a potential back  refer-
+       ence  number.   If  the  pattern continues with a digit character, some
+       delimiter must  be  used  to  terminate  the  back  reference.  If  the
+       PCRE_EXTENDED  option  is  set, this can be white space. Otherwise, the
+       \g{ syntax or an empty comment (see "Comments" below) can be used.
+
+   Recursive back references
+
+       A back reference that occurs inside the parentheses to which it  refers
+       fails  when  the subpattern is first used, so, for example, (a\1) never
+       matches.  However, such references can be useful inside  repeated  sub-
+       patterns. For example, the pattern
+
+         (a|b\1)+
+
+       matches any number of "a"s and also "aba", "ababbaa" etc. At each iter-
+       ation of the subpattern,  the  back  reference  matches  the  character
+       string  corresponding  to  the previous iteration. In order for this to
+       work, the pattern must be such that the first iteration does  not  need
+       to  match the back reference. This can be done using alternation, as in
+       the example above, or by a quantifier with a minimum of zero.
+
+       Back references of this type cause the group that they reference to  be
+       treated  as  an atomic group.  Once the whole group has been matched, a
+       subsequent matching failure cannot cause backtracking into  the  middle
+       of the group.
+
+
+ASSERTIONS
+
+       An  assertion  is  a  test on the characters following or preceding the
+       current matching point that does not actually consume  any  characters.
+       The  simple  assertions  coded  as  \b, \B, \A, \G, \Z, \z, ^ and $ are
+       described above.
+
+       More complicated assertions are coded as  subpatterns.  There  are  two
+       kinds:  those  that  look  ahead of the current position in the subject
+       string, and those that look  behind  it.  An  assertion  subpattern  is
+       matched  in  the  normal way, except that it does not cause the current
+       matching position to be changed.
+
+       Assertion subpatterns are not capturing subpatterns. If such an  asser-
+       tion  contains  capturing  subpatterns within it, these are counted for
+       the purposes of numbering the capturing subpatterns in the  whole  pat-
+       tern.  However,  substring  capturing  is carried out only for positive
+       assertions. (Perl sometimes, but not always, does do capturing in nega-
+       tive assertions.)
+
+       For  compatibility  with  Perl,  assertion subpatterns may be repeated;
+       though it makes no sense to assert the same thing  several  times,  the
+       side  effect  of  capturing  parentheses may occasionally be useful. In
+       practice, there only three cases:
+
+       (1) If the quantifier is {0}, the  assertion  is  never  obeyed  during
+       matching.   However,  it  may  contain internal capturing parenthesized
+       groups that are called from elsewhere via the subroutine mechanism.
+
+       (2) If quantifier is {0,n} where n is greater than zero, it is  treated
+       as  if  it  were  {0,1}.  At run time, the rest of the pattern match is
+       tried with and without the assertion, the order depending on the greed-
+       iness of the quantifier.
+
+       (3)  If  the minimum repetition is greater than zero, the quantifier is
+       ignored.  The assertion is obeyed just  once  when  encountered  during
+       matching.
+
+   Lookahead assertions
+
+       Lookahead assertions start with (?= for positive assertions and (?! for
+       negative assertions. For example,
+
+         \w+(?=;)
+
+       matches a word followed by a semicolon, but does not include the  semi-
+       colon in the match, and
+
+         foo(?!bar)
+
+       matches  any  occurrence  of  "foo" that is not followed by "bar". Note
+       that the apparently similar pattern
+
+         (?!foo)bar
+
+       does not find an occurrence of "bar"  that  is  preceded  by  something
+       other  than "foo"; it finds any occurrence of "bar" whatsoever, because
+       the assertion (?!foo) is always true when the next three characters are
+       "bar". A lookbehind assertion is needed to achieve the other effect.
+
+       If you want to force a matching failure at some point in a pattern, the
+       most convenient way to do it is  with  (?!)  because  an  empty  string
+       always  matches, so an assertion that requires there not to be an empty
+       string must always fail.  The backtracking control verb (*FAIL) or (*F)
+       is a synonym for (?!).
+
+   Lookbehind assertions
+
+       Lookbehind  assertions start with (?<= for positive assertions and (?<!
+       for negative assertions. For example,
+
+         (?<!foo)bar
+
+       does find an occurrence of "bar" that is not  preceded  by  "foo".  The
+       contents  of  a  lookbehind  assertion are restricted such that all the
+       strings it matches must have a fixed length. However, if there are sev-
+       eral  top-level  alternatives,  they  do  not all have to have the same
+       fixed length. Thus
+
+         (?<=bullock|donkey)
+
+       is permitted, but
+
+         (?<!dogs?|cats?)
+
+       causes an error at compile time. Branches that match  different  length
+       strings  are permitted only at the top level of a lookbehind assertion.
+       This is an extension compared with Perl, which requires all branches to
+       match the same length of string. An assertion such as
+
+         (?<=ab(c|de))
+
+       is  not  permitted,  because  its single top-level branch can match two
+       different lengths, but it is acceptable to PCRE if rewritten to use two
+       top-level branches:
+
+         (?<=abc|abde)
+
+       In  some  cases, the escape sequence \K (see above) can be used instead
+       of a lookbehind assertion to get round the fixed-length restriction.
+
+       The implementation of lookbehind assertions is, for  each  alternative,
+       to  temporarily  move the current position back by the fixed length and
+       then try to match. If there are insufficient characters before the cur-
+       rent position, the assertion fails.
+
+       In  a UTF mode, PCRE does not allow the \C escape (which matches a sin-
+       gle data unit even in a UTF mode) to appear in  lookbehind  assertions,
+       because  it  makes it impossible to calculate the length of the lookbe-
+       hind. The \X and \R escapes, which can match different numbers of  data
+       units, are also not permitted.
+
+       "Subroutine"  calls  (see below) such as (?2) or (?&X) are permitted in
+       lookbehinds, as long as the subpattern matches a  fixed-length  string.
+       Recursion, however, is not supported.
+
+       Possessive  quantifiers  can  be  used  in  conjunction with lookbehind
+       assertions to specify efficient matching of fixed-length strings at the
+       end of subject strings. Consider a simple pattern such as
+
+         abcd$
+
+       when  applied  to  a  long string that does not match. Because matching
+       proceeds from left to right, PCRE will look for each "a" in the subject
+       and  then  see  if what follows matches the rest of the pattern. If the
+       pattern is specified as
+
+         ^.*abcd$
+
+       the initial .* matches the entire string at first, but when this  fails
+       (because there is no following "a"), it backtracks to match all but the
+       last character, then all but the last two characters, and so  on.  Once
+       again  the search for "a" covers the entire string, from right to left,
+       so we are no better off. However, if the pattern is written as
+
+         ^.*+(?<=abcd)
+
+       there can be no backtracking for the .*+ item; it can  match  only  the
+       entire  string.  The subsequent lookbehind assertion does a single test
+       on the last four characters. If it fails, the match fails  immediately.
+       For  long  strings, this approach makes a significant difference to the
+       processing time.
+
+   Using multiple assertions
+
+       Several assertions (of any sort) may occur in succession. For example,
+
+         (?<=\d{3})(?<!999)foo
+
+       matches "foo" preceded by three digits that are not "999". Notice  that
+       each  of  the  assertions is applied independently at the same point in
+       the subject string. First there is a  check  that  the  previous  three
+       characters  are  all  digits,  and  then there is a check that the same
+       three characters are not "999".  This pattern does not match "foo" pre-
+       ceded  by  six  characters,  the first of which are digits and the last
+       three of which are not "999". For example, it  doesn't  match  "123abc-
+       foo". A pattern to do that is
+
+         (?<=\d{3}...)(?<!999)foo
+
+       This  time  the  first assertion looks at the preceding six characters,
+       checking that the first three are digits, and then the second assertion
+       checks that the preceding three characters are not "999".
+
+       Assertions can be nested in any combination. For example,
+
+         (?<=(?<!foo)bar)baz
+
+       matches  an occurrence of "baz" that is preceded by "bar" which in turn
+       is not preceded by "foo", while
+
+         (?<=\d{3}(?!999)...)foo
+
+       is another pattern that matches "foo" preceded by three digits and  any
+       three characters that are not "999".
+
+
+CONDITIONAL SUBPATTERNS
+
+       It  is possible to cause the matching process to obey a subpattern con-
+       ditionally or to choose between two alternative subpatterns,  depending
+       on  the result of an assertion, or whether a specific capturing subpat-
+       tern has already been matched. The two possible  forms  of  conditional
+       subpattern are:
+
+         (?(condition)yes-pattern)
+         (?(condition)yes-pattern|no-pattern)
+
+       If  the  condition is satisfied, the yes-pattern is used; otherwise the
+       no-pattern (if present) is used. If there are more  than  two  alterna-
+       tives  in  the subpattern, a compile-time error occurs. Each of the two
+       alternatives may itself contain nested subpatterns of any form, includ-
+       ing  conditional  subpatterns;  the  restriction  to  two  alternatives
+       applies only at the level of the condition. This pattern fragment is an
+       example where the alternatives are complex:
+
+         (?(1) (A|B|C) | (D | (?(2)E|F) | E) )
+
+
+       There  are  four  kinds of condition: references to subpatterns, refer-
+       ences to recursion, a pseudo-condition called DEFINE, and assertions.
+
+   Checking for a used subpattern by number
+
+       If the text between the parentheses consists of a sequence  of  digits,
+       the condition is true if a capturing subpattern of that number has pre-
+       viously matched. If there is more than one  capturing  subpattern  with
+       the  same  number  (see  the earlier section about duplicate subpattern
+       numbers), the condition is true if any of them have matched. An  alter-
+       native  notation is to precede the digits with a plus or minus sign. In
+       this case, the subpattern number is relative rather than absolute.  The
+       most  recently opened parentheses can be referenced by (?(-1), the next
+       most recent by (?(-2), and so on. Inside loops it can also  make  sense
+       to refer to subsequent groups. The next parentheses to be opened can be
+       referenced as (?(+1), and so on. (The value zero in any of these  forms
+       is not used; it provokes a compile-time error.)
+
+       Consider  the  following  pattern, which contains non-significant white
+       space to make it more readable (assume the PCRE_EXTENDED option) and to
+       divide it into three parts for ease of discussion:
+
+         ( \( )?    [^()]+    (?(1) \) )
+
+       The  first  part  matches  an optional opening parenthesis, and if that
+       character is present, sets it as the first captured substring. The sec-
+       ond  part  matches one or more characters that are not parentheses. The
+       third part is a conditional subpattern that tests whether  or  not  the
+       first  set  of  parentheses  matched.  If they did, that is, if subject
+       started with an opening parenthesis, the condition is true, and so  the
+       yes-pattern  is  executed and a closing parenthesis is required. Other-
+       wise, since no-pattern is not present, the subpattern matches  nothing.
+       In  other  words,  this  pattern matches a sequence of non-parentheses,
+       optionally enclosed in parentheses.
+
+       If you were embedding this pattern in a larger one,  you  could  use  a
+       relative reference:
+
+         ...other stuff... ( \( )?    [^()]+    (?(-1) \) ) ...
+
+       This  makes  the  fragment independent of the parentheses in the larger
+       pattern.
+
+   Checking for a used subpattern by name
+
+       Perl uses the syntax (?(<name>)...) or (?('name')...)  to  test  for  a
+       used  subpattern  by  name.  For compatibility with earlier versions of
+       PCRE, which had this facility before Perl, the syntax  (?(name)...)  is
+       also recognized.
+
+       Rewriting the above example to use a named subpattern gives this:
+
+         (?<OPEN> \( )?    [^()]+    (?(<OPEN>) \) )
+
+       If  the  name used in a condition of this kind is a duplicate, the test
+       is applied to all subpatterns of the same name, and is true if any  one
+       of them has matched.
+
+   Checking for pattern recursion
+
+       If the condition is the string (R), and there is no subpattern with the
+       name R, the condition is true if a recursive call to the whole  pattern
+       or any subpattern has been made. If digits or a name preceded by amper-
+       sand follow the letter R, for example:
+
+         (?(R3)...) or (?(R&name)...)
+
+       the condition is true if the most recent recursion is into a subpattern
+       whose number or name is given. This condition does not check the entire
+       recursion stack. If the name used in a condition  of  this  kind  is  a
+       duplicate, the test is applied to all subpatterns of the same name, and
+       is true if any one of them is the most recent recursion.
+
+       At "top level", all these recursion test  conditions  are  false.   The
+       syntax for recursive patterns is described below.
+
+   Defining subpatterns for use by reference only
+
+       If  the  condition  is  the string (DEFINE), and there is no subpattern
+       with the name DEFINE, the condition is  always  false.  In  this  case,
+       there  may  be  only  one  alternative  in the subpattern. It is always
+       skipped if control reaches this point  in  the  pattern;  the  idea  of
+       DEFINE  is that it can be used to define subroutines that can be refer-
+       enced from elsewhere. (The use of subroutines is described below.)  For
+       example,  a  pattern  to match an IPv4 address such as "192.168.23.245"
+       could be written like this (ignore white space and line breaks):
+
+         (?(DEFINE) (?<byte> 2[0-4]\d | 25[0-5] | 1\d\d | [1-9]?\d) )
+         \b (?&byte) (\.(?&byte)){3} \b
+
+       The first part of the pattern is a DEFINE group inside which a  another
+       group  named "byte" is defined. This matches an individual component of
+       an IPv4 address (a number less than 256). When  matching  takes  place,
+       this  part  of  the pattern is skipped because DEFINE acts like a false
+       condition. The rest of the pattern uses references to the  named  group
+       to  match the four dot-separated components of an IPv4 address, insist-
+       ing on a word boundary at each end.
+
+   Assertion conditions
+
+       If the condition is not in any of the above  formats,  it  must  be  an
+       assertion.   This may be a positive or negative lookahead or lookbehind
+       assertion. Consider  this  pattern,  again  containing  non-significant
+       white space, and with the two alternatives on the second line:
+
+         (?(?=[^a-z]*[a-z])
+         \d{2}-[a-z]{3}-\d{2}  |  \d{2}-\d{2}-\d{2} )
+
+       The  condition  is  a  positive  lookahead  assertion  that  matches an
+       optional sequence of non-letters followed by a letter. In other  words,
+       it  tests  for the presence of at least one letter in the subject. If a
+       letter is found, the subject is matched against the first  alternative;
+       otherwise  it  is  matched  against  the  second.  This pattern matches
+       strings in one of the two forms dd-aaa-dd or dd-dd-dd,  where  aaa  are
+       letters and dd are digits.
+
+
+COMMENTS
+
+       There are two ways of including comments in patterns that are processed
+       by PCRE. In both cases, the start of the comment must not be in a char-
+       acter class, nor in the middle of any other sequence of related charac-
+       ters such as (?: or a subpattern name or number.  The  characters  that
+       make up a comment play no part in the pattern matching.
+
+       The  sequence (?# marks the start of a comment that continues up to the
+       next closing parenthesis. Nested parentheses are not permitted. If  the
+       PCRE_EXTENDED option is set, an unescaped # character also introduces a
+       comment, which in this case continues to  immediately  after  the  next
+       newline  character  or character sequence in the pattern. Which charac-
+       ters are interpreted as newlines is controlled by the options passed to
+       a  compiling function or by a special sequence at the start of the pat-
+       tern, as described in the section entitled "Newline conventions" above.
+       Note that the end of this type of comment is a literal newline sequence
+       in the pattern; escape sequences that happen to represent a newline  do
+       not  count.  For  example,  consider this pattern when PCRE_EXTENDED is
+       set, and the default newline convention is in force:
+
+         abc #comment \n still comment
+
+       On encountering the # character, pcre_compile()  skips  along,  looking
+       for  a newline in the pattern. The sequence \n is still literal at this
+       stage, so it does not terminate the comment. Only an  actual  character
+       with the code value 0x0a (the default newline) does so.
+
+
+RECURSIVE PATTERNS
+
+       Consider  the problem of matching a string in parentheses, allowing for
+       unlimited nested parentheses. Without the use of  recursion,  the  best
+       that  can  be  done  is  to use a pattern that matches up to some fixed
+       depth of nesting. It is not possible to  handle  an  arbitrary  nesting
+       depth.
+
+       For some time, Perl has provided a facility that allows regular expres-
+       sions to recurse (amongst other things). It does this by  interpolating
+       Perl  code in the expression at run time, and the code can refer to the
+       expression itself. A Perl pattern using code interpolation to solve the
+       parentheses problem can be created like this:
+
+         $re = qr{\( (?: (?>[^()]+) | (?p{$re}) )* \)}x;
+
+       The (?p{...}) item interpolates Perl code at run time, and in this case
+       refers recursively to the pattern in which it appears.
+
+       Obviously, PCRE cannot support the interpolation of Perl code. Instead,
+       it  supports  special  syntax  for recursion of the entire pattern, and
+       also for individual subpattern recursion.  After  its  introduction  in
+       PCRE  and  Python,  this  kind of recursion was subsequently introduced
+       into Perl at release 5.10.
+
+       A special item that consists of (? followed by a  number  greater  than
+       zero  and  a  closing parenthesis is a recursive subroutine call of the
+       subpattern of the given number, provided that  it  occurs  inside  that
+       subpattern.  (If  not,  it is a non-recursive subroutine call, which is
+       described in the next section.) The special item  (?R)  or  (?0)  is  a
+       recursive call of the entire regular expression.
+
+       This  PCRE  pattern  solves  the nested parentheses problem (assume the
+       PCRE_EXTENDED option is set so that white space is ignored):
+
+         \( ( [^()]++ | (?R) )* \)
+
+       First it matches an opening parenthesis. Then it matches any number  of
+       substrings  which  can  either  be  a sequence of non-parentheses, or a
+       recursive match of the pattern itself (that is, a  correctly  parenthe-
+       sized substring).  Finally there is a closing parenthesis. Note the use
+       of a possessive quantifier to avoid backtracking into sequences of non-
+       parentheses.
+
+       If  this  were  part of a larger pattern, you would not want to recurse
+       the entire pattern, so instead you could use this:
+
+         ( \( ( [^()]++ | (?1) )* \) )
+
+       We have put the pattern into parentheses, and caused the  recursion  to
+       refer to them instead of the whole pattern.
+
+       In  a  larger  pattern,  keeping  track  of  parenthesis numbers can be
+       tricky. This is made easier by the use of relative references.  Instead
+       of (?1) in the pattern above you can write (?-2) to refer to the second
+       most recently opened parentheses  preceding  the  recursion.  In  other
+       words,  a  negative  number counts capturing parentheses leftwards from
+       the point at which it is encountered.
+
+       It is also possible to refer to  subsequently  opened  parentheses,  by
+       writing  references  such  as (?+2). However, these cannot be recursive
+       because the reference is not inside the  parentheses  that  are  refer-
+       enced.  They are always non-recursive subroutine calls, as described in
+       the next section.
+
+       An alternative approach is to use named parentheses instead.  The  Perl
+       syntax  for  this  is (?&name); PCRE's earlier syntax (?P>name) is also
+       supported. We could rewrite the above example as follows:
+
+         (?<pn> \( ( [^()]++ | (?&pn) )* \) )
+
+       If there is more than one subpattern with the same name,  the  earliest
+       one is used.
+
+       This  particular  example pattern that we have been looking at contains
+       nested unlimited repeats, and so the use of a possessive quantifier for
+       matching strings of non-parentheses is important when applying the pat-
+       tern to strings that do not match. For example, when  this  pattern  is
+       applied to
+
+         (aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa()
+
+       it  yields  "no  match" quickly. However, if a possessive quantifier is
+       not used, the match runs for a very long time indeed because there  are
+       so  many  different  ways the + and * repeats can carve up the subject,
+       and all have to be tested before failure can be reported.
+
+       At the end of a match, the values of capturing  parentheses  are  those
+       from  the outermost level. If you want to obtain intermediate values, a
+       callout function can be used (see below and the pcrecallout  documenta-
+       tion). If the pattern above is matched against
+
+         (ab(cd)ef)
+
+       the  value  for  the  inner capturing parentheses (numbered 2) is "ef",
+       which is the last value taken on at the top level. If a capturing  sub-
+       pattern  is  not  matched at the top level, its final captured value is
+       unset, even if it was (temporarily) set at a deeper  level  during  the
+       matching process.
+
+       If  there are more than 15 capturing parentheses in a pattern, PCRE has
+       to obtain extra memory to store data during a recursion, which it  does
+       by using pcre_malloc, freeing it via pcre_free afterwards. If no memory
+       can be obtained, the match fails with the PCRE_ERROR_NOMEMORY error.
+
+       Do not confuse the (?R) item with the condition (R),  which  tests  for
+       recursion.   Consider  this pattern, which matches text in angle brack-
+       ets, allowing for arbitrary nesting. Only digits are allowed in  nested
+       brackets  (that is, when recursing), whereas any characters are permit-
+       ted at the outer level.
+
+         < (?: (?(R) \d++  | [^<>]*+) | (?R)) * >
+
+       In this pattern, (?(R) is the start of a conditional  subpattern,  with
+       two  different  alternatives for the recursive and non-recursive cases.
+       The (?R) item is the actual recursive call.
+
+   Differences in recursion processing between PCRE and Perl
+
+       Recursion processing in PCRE differs from Perl in two  important  ways.
+       In  PCRE (like Python, but unlike Perl), a recursive subpattern call is
+       always treated as an atomic group. That is, once it has matched some of
+       the subject string, it is never re-entered, even if it contains untried
+       alternatives and there is a subsequent matching failure.  This  can  be
+       illustrated  by the following pattern, which purports to match a palin-
+       dromic string that contains an odd number of characters  (for  example,
+       "a", "aba", "abcba", "abcdcba"):
+
+         ^(.|(.)(?1)\2)$
+
+       The idea is that it either matches a single character, or two identical
+       characters surrounding a sub-palindrome. In Perl, this  pattern  works;
+       in  PCRE  it  does  not if the pattern is longer than three characters.
+       Consider the subject string "abcba":
+
+       At the top level, the first character is matched, but as it is  not  at
+       the end of the string, the first alternative fails; the second alterna-
+       tive is taken and the recursion kicks in. The recursive call to subpat-
+       tern  1  successfully  matches the next character ("b"). (Note that the
+       beginning and end of line tests are not part of the recursion).
+
+       Back at the top level, the next character ("c") is compared  with  what
+       subpattern  2 matched, which was "a". This fails. Because the recursion
+       is treated as an atomic group, there are now  no  backtracking  points,
+       and  so  the  entire  match fails. (Perl is able, at this point, to re-
+       enter the recursion and try the second alternative.)  However,  if  the
+       pattern is written with the alternatives in the other order, things are
+       different:
+
+         ^((.)(?1)\2|.)$
+
+       This time, the recursing alternative is tried first, and  continues  to
+       recurse  until  it runs out of characters, at which point the recursion
+       fails. But this time we do have  another  alternative  to  try  at  the
+       higher  level.  That  is  the  big difference: in the previous case the
+       remaining alternative is at a deeper recursion level, which PCRE cannot
+       use.
+
+       To  change  the pattern so that it matches all palindromic strings, not
+       just those with an odd number of characters, it is tempting  to  change
+       the pattern to this:
+
+         ^((.)(?1)\2|.?)$
+
+       Again,  this  works  in Perl, but not in PCRE, and for the same reason.
+       When a deeper recursion has matched a single character,  it  cannot  be
+       entered  again  in  order  to match an empty string. The solution is to
+       separate the two cases, and write out the odd and even cases as  alter-
+       natives at the higher level:
+
+         ^(?:((.)(?1)\2|)|((.)(?3)\4|.))
+
+       If  you  want  to match typical palindromic phrases, the pattern has to
+       ignore all non-word characters, which can be done like this:
+
+         ^\W*+(?:((.)\W*+(?1)\W*+\2|)|((.)\W*+(?3)\W*+\4|\W*+.\W*+))\W*+$
+
+       If run with the PCRE_CASELESS option, this pattern matches phrases such
+       as "A man, a plan, a canal: Panama!" and it works well in both PCRE and
+       Perl. Note the use of the possessive quantifier *+ to avoid  backtrack-
+       ing  into  sequences of non-word characters. Without this, PCRE takes a
+       great deal longer (ten times or more) to  match  typical  phrases,  and
+       Perl takes so long that you think it has gone into a loop.
+
+       WARNING:  The  palindrome-matching patterns above work only if the sub-
+       ject string does not start with a palindrome that is shorter  than  the
+       entire  string.  For example, although "abcba" is correctly matched, if
+       the subject is "ababa", PCRE finds the palindrome "aba" at  the  start,
+       then  fails at top level because the end of the string does not follow.
+       Once again, it cannot jump back into the recursion to try other  alter-
+       natives, so the entire match fails.
+
+       The  second  way  in which PCRE and Perl differ in their recursion pro-
+       cessing is in the handling of captured values. In Perl, when a  subpat-
+       tern  is  called recursively or as a subpattern (see the next section),
+       it has no access to any values that were captured  outside  the  recur-
+       sion,  whereas  in  PCRE  these values can be referenced. Consider this
+       pattern:
+
+         ^(.)(\1|a(?2))
+
+       In PCRE, this pattern matches "bab". The  first  capturing  parentheses
+       match  "b",  then in the second group, when the back reference \1 fails
+       to match "b", the second alternative matches "a" and then recurses.  In
+       the  recursion,  \1 does now match "b" and so the whole match succeeds.
+       In Perl, the pattern fails to match because inside the  recursive  call
+       \1 cannot access the externally set value.
+
+
+SUBPATTERNS AS SUBROUTINES
+
+       If  the  syntax for a recursive subpattern call (either by number or by
+       name) is used outside the parentheses to which it refers,  it  operates
+       like  a subroutine in a programming language. The called subpattern may
+       be defined before or after the reference. A numbered reference  can  be
+       absolute or relative, as in these examples:
+
+         (...(absolute)...)...(?2)...
+         (...(relative)...)...(?-1)...
+         (...(?+1)...(relative)...
+
+       An earlier example pointed out that the pattern
+
+         (sens|respons)e and \1ibility
+
+       matches  "sense and sensibility" and "response and responsibility", but
+       not "sense and responsibility". If instead the pattern
+
+         (sens|respons)e and (?1)ibility
+
+       is used, it does match "sense and responsibility" as well as the  other
+       two  strings.  Another  example  is  given  in the discussion of DEFINE
+       above.
+
+       All subroutine calls, whether recursive or not, are always  treated  as
+       atomic  groups. That is, once a subroutine has matched some of the sub-
+       ject string, it is never re-entered, even if it contains untried alter-
+       natives  and  there  is  a  subsequent  matching failure. Any capturing
+       parentheses that are set during the subroutine  call  revert  to  their
+       previous values afterwards.
+
+       Processing  options  such as case-independence are fixed when a subpat-
+       tern is defined, so if it is used as a subroutine, such options  cannot
+       be changed for different calls. For example, consider this pattern:
+
+         (abc)(?i:(?-1))
+
+       It  matches  "abcabc". It does not match "abcABC" because the change of
+       processing option does not affect the called subpattern.
+
+
+ONIGURUMA SUBROUTINE SYNTAX
+
+       For compatibility with Oniguruma, the non-Perl syntax \g followed by  a
+       name or a number enclosed either in angle brackets or single quotes, is
+       an alternative syntax for referencing a  subpattern  as  a  subroutine,
+       possibly  recursively. Here are two of the examples used above, rewrit-
+       ten using this syntax:
+
+         (?<pn> \( ( (?>[^()]+) | \g<pn> )* \) )
+         (sens|respons)e and \g'1'ibility
+
+       PCRE supports an extension to Oniguruma: if a number is preceded  by  a
+       plus or a minus sign it is taken as a relative reference. For example:
+
+         (abc)(?i:\g<-1>)
+
+       Note  that \g{...} (Perl syntax) and \g<...> (Oniguruma syntax) are not
+       synonymous. The former is a back reference; the latter is a  subroutine
+       call.
+
+
+CALLOUTS
+
+       Perl has a feature whereby using the sequence (?{...}) causes arbitrary
+       Perl code to be obeyed in the middle of matching a regular  expression.
+       This makes it possible, amongst other things, to extract different sub-
+       strings that match the same pair of parentheses when there is a repeti-
+       tion.
+
+       PCRE provides a similar feature, but of course it cannot obey arbitrary
+       Perl code. The feature is called "callout". The caller of PCRE provides
+       an  external function by putting its entry point in the global variable
+       pcre_callout (8-bit library) or pcre[16|32]_callout (16-bit  or  32-bit
+       library).   By default, this variable contains NULL, which disables all
+       calling out.
+
+       Within a regular expression, (?C) indicates the  points  at  which  the
+       external  function  is  to be called. If you want to identify different
+       callout points, you can put a number less than 256 after the letter  C.
+       The  default  value is zero.  For example, this pattern has two callout
+       points:
+
+         (?C1)abc(?C2)def
+
+       If the PCRE_AUTO_CALLOUT flag is passed to a compiling function,  call-
+       outs  are automatically installed before each item in the pattern. They
+       are all numbered 255. If there is a conditional group  in  the  pattern
+       whose condition is an assertion, an additional callout is inserted just
+       before the condition. An explicit callout may also be set at this posi-
+       tion, as in this example:
+
+         (?(?C9)(?=a)abc|def)
+
+       Note that this applies only to assertion conditions, not to other types
+       of condition.
+
+       During matching, when PCRE reaches a callout point, the external  func-
+       tion  is  called.  It  is  provided with the number of the callout, the
+       position in the pattern, and, optionally, one item of  data  originally
+       supplied  by  the caller of the matching function. The callout function
+       may cause matching to proceed, to backtrack, or to fail altogether.
+
+       By default, PCRE implements a number of optimizations at  compile  time
+       and  matching  time, and one side-effect is that sometimes callouts are
+       skipped. If you need all possible callouts to happen, you need  to  set
+       options  that  disable  the relevant optimizations. More details, and a
+       complete description of the interface  to  the  callout  function,  are
+       given in the pcrecallout documentation.
+
+
+BACKTRACKING CONTROL
+
+       Perl  5.10 introduced a number of "Special Backtracking Control Verbs",
+       which are still described in the Perl  documentation  as  "experimental
+       and  subject to change or removal in a future version of Perl". It goes
+       on to say: "Their usage in production code should  be  noted  to  avoid
+       problems  during upgrades." The same remarks apply to the PCRE features
+       described in this section.
+
+       The new verbs make use of what was previously invalid syntax: an  open-
+       ing parenthesis followed by an asterisk. They are generally of the form
+       (*VERB) or (*VERB:NAME). Some may take either form,  possibly  behaving
+       differently  depending  on  whether or not a name is present. A name is
+       any sequence of characters that does not include a closing parenthesis.
+       The maximum length of name is 255 in the 8-bit library and 65535 in the
+       16-bit and 32-bit libraries. If the name is  empty,  that  is,  if  the
+       closing  parenthesis immediately follows the colon, the effect is as if
+       the colon were not there.  Any number of these verbs  may  occur  in  a
+       pattern.
+
+       Since  these  verbs  are  specifically related to backtracking, most of
+       them can be used only when the pattern is to be matched  using  one  of
+       the  traditional  matching  functions, because these use a backtracking
+       algorithm. With the exception of (*FAIL), which behaves like a  failing
+       negative  assertion,  the  backtracking control verbs cause an error if
+       encountered by a DFA matching function.
+
+       The behaviour of these verbs in repeated  groups,  assertions,  and  in
+       subpatterns called as subroutines (whether or not recursively) is docu-
+       mented below.
+
+   Optimizations that affect backtracking verbs
+
+       PCRE contains some optimizations that are used to speed up matching  by
+       running some checks at the start of each match attempt. For example, it
+       may know the minimum length of matching subject, or that  a  particular
+       character must be present. When one of these optimizations bypasses the
+       running of a match,  any  included  backtracking  verbs  will  not,  of
+       course, be processed. You can suppress the start-of-match optimizations
+       by setting the PCRE_NO_START_OPTIMIZE  option  when  calling  pcre_com-
+       pile() or pcre_exec(), or by starting the pattern with (*NO_START_OPT).
+       There is more discussion of this option in the section entitled "Option
+       bits for pcre_exec()" in the pcreapi documentation.
+
+       Experiments  with  Perl  suggest that it too has similar optimizations,
+       sometimes leading to anomalous results.
+
+   Verbs that act immediately
+
+       The following verbs act as soon as they are encountered. They  may  not
+       be followed by a name.
+
+          (*ACCEPT)
+
+       This  verb causes the match to end successfully, skipping the remainder
+       of the pattern. However, when it is inside a subpattern that is  called
+       as  a  subroutine, only that subpattern is ended successfully. Matching
+       then continues at the outer level. If (*ACCEPT) in triggered in a posi-
+       tive  assertion,  the  assertion succeeds; in a negative assertion, the
+       assertion fails.
+
+       If (*ACCEPT) is inside capturing parentheses, the data so far  is  cap-
+       tured. For example:
+
+         A((?:A|B(*ACCEPT)|C)D)
+
+       This  matches  "AB", "AAD", or "ACD"; when it matches "AB", "B" is cap-
+       tured by the outer parentheses.
+
+         (*FAIL) or (*F)
+
+       This verb causes a matching failure, forcing backtracking to occur.  It
+       is  equivalent to (?!) but easier to read. The Perl documentation notes
+       that it is probably useful only when combined  with  (?{})  or  (??{}).
+       Those  are,  of course, Perl features that are not present in PCRE. The
+       nearest equivalent is the callout feature, as for example in this  pat-
+       tern:
+
+         a+(?C)(*FAIL)
+
+       A  match  with the string "aaaa" always fails, but the callout is taken
+       before each backtrack happens (in this example, 10 times).
+
+   Recording which path was taken
+
+       There is one verb whose main purpose  is  to  track  how  a  match  was
+       arrived  at,  though  it  also  has a secondary use in conjunction with
+       advancing the match starting point (see (*SKIP) below).
+
+         (*MARK:NAME) or (*:NAME)
+
+       A name is always  required  with  this  verb.  There  may  be  as  many
+       instances  of  (*MARK) as you like in a pattern, and their names do not
+       have to be unique.
+
+       When a match succeeds, the name of the  last-encountered  (*MARK:NAME),
+       (*PRUNE:NAME),  or  (*THEN:NAME) on the matching path is passed back to
+       the caller as  described  in  the  section  entitled  "Extra  data  for
+       pcre_exec()"  in  the  pcreapi  documentation.  Here  is  an example of
+       pcretest output, where the /K modifier requests the retrieval and  out-
+       putting of (*MARK) data:
+
+           re> /X(*MARK:A)Y|X(*MARK:B)Z/K
+         data> XY
+          0: XY
+         MK: A
+         XZ
+          0: XZ
+         MK: B
+
+       The (*MARK) name is tagged with "MK:" in this output, and in this exam-
+       ple it indicates which of the two alternatives matched. This is a  more
+       efficient  way of obtaining this information than putting each alterna-
+       tive in its own capturing parentheses.
+
+       If a verb with a name is encountered in a positive  assertion  that  is
+       true,  the  name  is recorded and passed back if it is the last-encoun-
+       tered. This does not happen for negative assertions or failing positive
+       assertions.
+
+       After  a  partial match or a failed match, the last encountered name in
+       the entire match process is returned. For example:
+
+           re> /X(*MARK:A)Y|X(*MARK:B)Z/K
+         data> XP
+         No match, mark = B
+
+       Note that in this unanchored example the  mark  is  retained  from  the
+       match attempt that started at the letter "X" in the subject. Subsequent
+       match attempts starting at "P" and then with an empty string do not get
+       as far as the (*MARK) item, but nevertheless do not reset it.
+
+       If  you  are  interested  in  (*MARK)  values after failed matches, you
+       should probably set the PCRE_NO_START_OPTIMIZE option  (see  above)  to
+       ensure that the match is always attempted.
+
+   Verbs that act after backtracking
+
+       The following verbs do nothing when they are encountered. Matching con-
+       tinues with what follows, but if there is no subsequent match,  causing
+       a  backtrack  to  the  verb, a failure is forced. That is, backtracking
+       cannot pass to the left of the verb. However, when one of  these  verbs
+       appears inside an atomic group or an assertion that is true, its effect
+       is confined to that group, because once the  group  has  been  matched,
+       there  is never any backtracking into it. In this situation, backtrack-
+       ing can "jump back" to the left of the entire atomic  group  or  asser-
+       tion.  (Remember  also,  as  stated  above, that this localization also
+       applies in subroutine calls.)
+
+       These verbs differ in exactly what kind of failure  occurs  when  back-
+       tracking  reaches  them.  The behaviour described below is what happens
+       when the verb is not in a subroutine or an assertion.  Subsequent  sec-
+       tions cover these special cases.
+
+         (*COMMIT)
+
+       This  verb, which may not be followed by a name, causes the whole match
+       to fail outright if there is a later matching failure that causes back-
+       tracking  to  reach  it.  Even if the pattern is unanchored, no further
+       attempts to find a match by advancing the starting point take place. If
+       (*COMMIT)  is  the  only backtracking verb that is encountered, once it
+       has been passed pcre_exec() is committed to finding a match at the cur-
+       rent starting point, or not at all. For example:
+
+         a+(*COMMIT)b
+
+       This  matches  "xxaab" but not "aacaab". It can be thought of as a kind
+       of dynamic anchor, or "I've started, so I must finish." The name of the
+       most  recently passed (*MARK) in the path is passed back when (*COMMIT)
+       forces a match failure.
+
+       If there is more than one backtracking verb in a pattern,  a  different
+       one  that  follows  (*COMMIT) may be triggered first, so merely passing
+       (*COMMIT) during a match does not always guarantee that a match must be
+       at this starting point.
+
+       Note  that  (*COMMIT)  at  the start of a pattern is not the same as an
+       anchor, unless PCRE's start-of-match optimizations are turned  off,  as
+       shown in this output from pcretest:
+
+           re> /(*COMMIT)abc/
+         data> xyzabc
+          0: abc
+         data> xyzabc\Y
+         No match
+
+       For this pattern, PCRE knows that any match must start with "a", so the
+       optimization skips along the subject to "a" before applying the pattern
+       to  the first set of data. The match attempt then succeeds. In the sec-
+       ond set of data, the escape sequence \Y is interpreted by the  pcretest
+       program.  It  causes  the  PCRE_NO_START_OPTIMIZE option to be set when
+       pcre_exec() is called.  This disables the optimization that skips along
+       to the first character. The pattern is now applied starting at "x", and
+       so the (*COMMIT) causes the match to  fail  without  trying  any  other
+       starting points.
+
+         (*PRUNE) or (*PRUNE:NAME)
+
+       This  verb causes the match to fail at the current starting position in
+       the subject if there is a later matching failure that causes backtrack-
+       ing  to  reach it. If the pattern is unanchored, the normal "bumpalong"
+       advance to the next starting character then happens.  Backtracking  can
+       occur  as  usual to the left of (*PRUNE), before it is reached, or when
+       matching to the right of (*PRUNE), but if there  is  no  match  to  the
+       right,  backtracking cannot cross (*PRUNE). In simple cases, the use of
+       (*PRUNE) is just an alternative to an atomic group or possessive  quan-
+       tifier, but there are some uses of (*PRUNE) that cannot be expressed in
+       any other way. In an anchored pattern (*PRUNE) has the same  effect  as
+       (*COMMIT).
+
+       The   behaviour   of   (*PRUNE:NAME)   is   the   not   the   same   as
+       (*MARK:NAME)(*PRUNE).  It is like (*MARK:NAME)  in  that  the  name  is
+       remembered  for  passing  back  to  the  caller.  However, (*SKIP:NAME)
+       searches only for names set with (*MARK).
+
+         (*SKIP)
+
+       This verb, when given without a name, is like (*PRUNE), except that  if
+       the  pattern  is unanchored, the "bumpalong" advance is not to the next
+       character, but to the position in the subject where (*SKIP) was encoun-
+       tered.  (*SKIP)  signifies that whatever text was matched leading up to
+       it cannot be part of a successful match. Consider:
+
+         a+(*SKIP)b
+
+       If the subject is "aaaac...",  after  the  first  match  attempt  fails
+       (starting  at  the  first  character in the string), the starting point
+       skips on to start the next attempt at "c". Note that a possessive quan-
+       tifer  does not have the same effect as this example; although it would
+       suppress backtracking  during  the  first  match  attempt,  the  second
+       attempt  would  start at the second character instead of skipping on to
+       "c".
+
+         (*SKIP:NAME)
+
+       When (*SKIP) has an associated name, its behaviour is modified. When it
+       is triggered, the previous path through the pattern is searched for the
+       most recent (*MARK) that has the  same  name.  If  one  is  found,  the
+       "bumpalong" advance is to the subject position that corresponds to that
+       (*MARK) instead of to where (*SKIP) was encountered. If no (*MARK) with
+       a matching name is found, the (*SKIP) is ignored.
+
+       Note  that (*SKIP:NAME) searches only for names set by (*MARK:NAME). It
+       ignores names that are set by (*PRUNE:NAME) or (*THEN:NAME).
+
+         (*THEN) or (*THEN:NAME)
+
+       This verb causes a skip to the next innermost  alternative  when  back-
+       tracking  reaches  it.  That  is,  it  cancels any further backtracking
+       within the current alternative. Its name  comes  from  the  observation
+       that it can be used for a pattern-based if-then-else block:
+
+         ( COND1 (*THEN) FOO | COND2 (*THEN) BAR | COND3 (*THEN) BAZ ) ...
+
+       If  the COND1 pattern matches, FOO is tried (and possibly further items
+       after the end of the group if FOO succeeds); on  failure,  the  matcher
+       skips  to  the second alternative and tries COND2, without backtracking
+       into COND1. If that succeeds and BAR fails, COND3 is tried.  If  subse-
+       quently  BAZ fails, there are no more alternatives, so there is a back-
+       track to whatever came before the  entire  group.  If  (*THEN)  is  not
+       inside an alternation, it acts like (*PRUNE).
+
+       The    behaviour   of   (*THEN:NAME)   is   the   not   the   same   as
+       (*MARK:NAME)(*THEN).  It is like  (*MARK:NAME)  in  that  the  name  is
+       remembered  for  passing  back  to  the  caller.  However, (*SKIP:NAME)
+       searches only for names set with (*MARK).
+
+       A subpattern that does not contain a | character is just a part of  the
+       enclosing  alternative;  it  is  not a nested alternation with only one
+       alternative. The effect of (*THEN) extends beyond such a subpattern  to
+       the  enclosing alternative. Consider this pattern, where A, B, etc. are
+       complex pattern fragments that do not contain any | characters at  this
+       level:
+
+         A (B(*THEN)C) | D
+
+       If  A and B are matched, but there is a failure in C, matching does not
+       backtrack into A; instead it moves to the next alternative, that is, D.
+       However,  if the subpattern containing (*THEN) is given an alternative,
+       it behaves differently:
+
+         A (B(*THEN)C | (*FAIL)) | D
+
+       The effect of (*THEN) is now confined to the inner subpattern. After  a
+       failure in C, matching moves to (*FAIL), which causes the whole subpat-
+       tern to fail because there are no more alternatives  to  try.  In  this
+       case, matching does now backtrack into A.
+
+       Note  that  a  conditional  subpattern  is not considered as having two
+       alternatives, because only one is ever used.  In  other  words,  the  |
+       character in a conditional subpattern has a different meaning. Ignoring
+       white space, consider:
+
+         ^.*? (?(?=a) a | b(*THEN)c )
+
+       If the subject is "ba", this pattern does not  match.  Because  .*?  is
+       ungreedy,  it  initially  matches  zero characters. The condition (?=a)
+       then fails, the character "b" is matched,  but  "c"  is  not.  At  this
+       point,  matching does not backtrack to .*? as might perhaps be expected
+       from the presence of the | character.  The  conditional  subpattern  is
+       part of the single alternative that comprises the whole pattern, and so
+       the match fails. (If there was a backtrack into  .*?,  allowing  it  to
+       match "b", the match would succeed.)
+
+       The  verbs just described provide four different "strengths" of control
+       when subsequent matching fails. (*THEN) is the weakest, carrying on the
+       match  at  the next alternative. (*PRUNE) comes next, failing the match
+       at the current starting position, but allowing an advance to  the  next
+       character  (for an unanchored pattern). (*SKIP) is similar, except that
+       the advance may be more than one character. (*COMMIT) is the strongest,
+       causing the entire match to fail.
+
+   More than one backtracking verb
+
+       If  more  than  one  backtracking verb is present in a pattern, the one
+       that is backtracked onto first acts. For example,  consider  this  pat-
+       tern, where A, B, etc. are complex pattern fragments:
+
+         (A(*COMMIT)B(*THEN)C|ABD)
+
+       If  A matches but B fails, the backtrack to (*COMMIT) causes the entire
+       match to fail. However, if A and B match, but C fails, the backtrack to
+       (*THEN)  causes  the next alternative (ABD) to be tried. This behaviour
+       is consistent, but is not always the same as Perl's. It means  that  if
+       two  or  more backtracking verbs appear in succession, all the the last
+       of them has no effect. Consider this example:
+
+         ...(*COMMIT)(*PRUNE)...
+
+       If there is a matching failure to the right, backtracking onto (*PRUNE)
+       causes  it to be triggered, and its action is taken. There can never be
+       a backtrack onto (*COMMIT).
+
+   Backtracking verbs in repeated groups
+
+       PCRE differs from  Perl  in  its  handling  of  backtracking  verbs  in
+       repeated groups. For example, consider:
+
+         /(a(*COMMIT)b)+ac/
+
+       If  the  subject  is  "abac",  Perl matches, but PCRE fails because the
+       (*COMMIT) in the second repeat of the group acts.
+
+   Backtracking verbs in assertions
+
+       (*FAIL) in an assertion has its normal effect: it forces  an  immediate
+       backtrack.
+
+       (*ACCEPT) in a positive assertion causes the assertion to succeed with-
+       out any further processing. In a negative assertion,  (*ACCEPT)  causes
+       the assertion to fail without any further processing.
+
+       The  other  backtracking verbs are not treated specially if they appear
+       in a positive assertion. In  particular,  (*THEN)  skips  to  the  next
+       alternative  in  the  innermost  enclosing group that has alternations,
+       whether or not this is within the assertion.
+
+       Negative assertions are, however, different, in order  to  ensure  that
+       changing  a  positive  assertion  into a negative assertion changes its
+       result. Backtracking into (*COMMIT), (*SKIP), or (*PRUNE) causes a neg-
+       ative assertion to be true, without considering any further alternative
+       branches in the assertion.  Backtracking into (*THEN) causes it to skip
+       to  the next enclosing alternative within the assertion (the normal be-
+       haviour), but if the assertion  does  not  have  such  an  alternative,
+       (*THEN) behaves like (*PRUNE).
+
+   Backtracking verbs in subroutines
+
+       These  behaviours  occur whether or not the subpattern is called recur-
+       sively.  Perl's treatment of subroutines is different in some cases.
+
+       (*FAIL) in a subpattern called as a subroutine has its  normal  effect:
+       it forces an immediate backtrack.
+
+       (*ACCEPT)  in a subpattern called as a subroutine causes the subroutine
+       match to succeed without any further processing. Matching then  contin-
+       ues after the subroutine call.
+
+       (*COMMIT), (*SKIP), and (*PRUNE) in a subpattern called as a subroutine
+       cause the subroutine match to fail.
+
+       (*THEN) skips to the next alternative in the innermost enclosing  group
+       within  the subpattern that has alternatives. If there is no such group
+       within the subpattern, (*THEN) causes the subroutine match to fail.
+
+
+SEE ALSO
+
+       pcreapi(3), pcrecallout(3),  pcrematching(3),  pcresyntax(3),  pcre(3),
+       pcre16(3), pcre32(3).
+
+
+AUTHOR
+
+       Philip Hazel
+       University Computing Service
+       Cambridge CB2 3QH, England.
+
+
+REVISION
+
+       Last updated: 08 January 2014
+       Copyright (c) 1997-2014 University of Cambridge.
+------------------------------------------------------------------------------
+
+
+PCRESYNTAX(3)              Library Functions Manual              PCRESYNTAX(3)
+
+
+
+NAME
+       PCRE - Perl-compatible regular expressions
+
+PCRE REGULAR EXPRESSION SYNTAX SUMMARY
+
+       The  full syntax and semantics of the regular expressions that are sup-
+       ported by PCRE are described in  the  pcrepattern  documentation.  This
+       document contains a quick-reference summary of the syntax.
+
+
+QUOTING
+
+         \x         where x is non-alphanumeric is a literal x
+         \Q...\E    treat enclosed characters as literal
+
+
+CHARACTERS
+
+         \a         alarm, that is, the BEL character (hex 07)
+         \cx        "control-x", where x is any ASCII character
+         \e         escape (hex 1B)
+         \f         form feed (hex 0C)
+         \n         newline (hex 0A)
+         \r         carriage return (hex 0D)
+         \t         tab (hex 09)
+         \0dd       character with octal code 0dd
+         \ddd       character with octal code ddd, or backreference
+         \o{ddd..}  character with octal code ddd..
+         \xhh       character with hex code hh
+         \x{hhh..}  character with hex code hhh..
+
+       Note that \0dd is always an octal code, and that \8 and \9 are the lit-
+       eral characters "8" and "9".
+
+
+CHARACTER TYPES
+
+         .          any character except newline;
+                      in dotall mode, any character whatsoever
+         \C         one data unit, even in UTF mode (best avoided)
+         \d         a decimal digit
+         \D         a character that is not a decimal digit
+         \h         a horizontal white space character
+         \H         a character that is not a horizontal white space character
+         \N         a character that is not a newline
+         \p{xx}     a character with the xx property
+         \P{xx}     a character without the xx property
+         \R         a newline sequence
+         \s         a white space character
+         \S         a character that is not a white space character
+         \v         a vertical white space character
+         \V         a character that is not a vertical white space character
+         \w         a "word" character
+         \W         a "non-word" character
+         \X         a Unicode extended grapheme cluster
+
+       By default, \d, \s, and \w match only ASCII characters, even  in  UTF-8
+       mode  or  in  the 16- bit and 32-bit libraries. However, if locale-spe-
+       cific matching is happening, \s and \w may also match  characters  with
+       code  points  in  the range 128-255. If the PCRE_UCP option is set, the
+       behaviour of these escape sequences is changed to use  Unicode  proper-
+       ties and they match many more characters.
+
+
+GENERAL CATEGORY PROPERTIES FOR \p and \P
+
+         C          Other
+         Cc         Control
+         Cf         Format
+         Cn         Unassigned
+         Co         Private use
+         Cs         Surrogate
+
+         L          Letter
+         Ll         Lower case letter
+         Lm         Modifier letter
+         Lo         Other letter
+         Lt         Title case letter
+         Lu         Upper case letter
+         L&         Ll, Lu, or Lt
+
+         M          Mark
+         Mc         Spacing mark
+         Me         Enclosing mark
+         Mn         Non-spacing mark
+
+         N          Number
+         Nd         Decimal number
+         Nl         Letter number
+         No         Other number
+
+         P          Punctuation
+         Pc         Connector punctuation
+         Pd         Dash punctuation
+         Pe         Close punctuation
+         Pf         Final punctuation
+         Pi         Initial punctuation
+         Po         Other punctuation
+         Ps         Open punctuation
+
+         S          Symbol
+         Sc         Currency symbol
+         Sk         Modifier symbol
+         Sm         Mathematical symbol
+         So         Other symbol
+
+         Z          Separator
+         Zl         Line separator
+         Zp         Paragraph separator
+         Zs         Space separator
+
+
+PCRE SPECIAL CATEGORY PROPERTIES FOR \p and \P
+
+         Xan        Alphanumeric: union of properties L and N
+         Xps        POSIX space: property Z or tab, NL, VT, FF, CR
+         Xsp        Perl space: property Z or tab, NL, VT, FF, CR
+         Xuc        Univerally-named character: one that can be
+                      represented by a Universal Character Name
+         Xwd        Perl word: property Xan or underscore
+
+       Perl and POSIX space are now the same. Perl added VT to its space char-
+       acter set at release 5.18 and PCRE changed at release 8.34.
+
+
+SCRIPT NAMES FOR \p AND \P
+
+       Arabic, Armenian, Avestan, Balinese, Bamum, Batak,  Bengali,  Bopomofo,
+       Brahmi,  Braille, Buginese, Buhid, Canadian_Aboriginal, Carian, Chakma,
+       Cham, Cherokee, Common, Coptic, Cuneiform, Cypriot, Cyrillic,  Deseret,
+       Devanagari,   Egyptian_Hieroglyphs,   Ethiopic,  Georgian,  Glagolitic,
+       Gothic, Greek, Gujarati, Gurmukhi, Han, Hangul, Hanunoo, Hebrew,  Hira-
+       gana,   Imperial_Aramaic,  Inherited,  Inscriptional_Pahlavi,  Inscrip-
+       tional_Parthian,  Javanese,  Kaithi,   Kannada,   Katakana,   Kayah_Li,
+       Kharoshthi,  Khmer,  Lao, Latin, Lepcha, Limbu, Linear_B, Lisu, Lycian,
+       Lydian,    Malayalam,    Mandaic,    Meetei_Mayek,    Meroitic_Cursive,
+       Meroitic_Hieroglyphs,   Miao,  Mongolian,  Myanmar,  New_Tai_Lue,  Nko,
+       Ogham,   Old_Italic,   Old_Persian,   Old_South_Arabian,    Old_Turkic,
+       Ol_Chiki,  Oriya, Osmanya, Phags_Pa, Phoenician, Rejang, Runic, Samari-
+       tan, Saurashtra, Sharada, Shavian,  Sinhala,  Sora_Sompeng,  Sundanese,
+       Syloti_Nagri,  Syriac,  Tagalog,  Tagbanwa, Tai_Le, Tai_Tham, Tai_Viet,
+       Takri, Tamil, Telugu, Thaana, Thai, Tibetan, Tifinagh,  Ugaritic,  Vai,
+       Yi.
+
+
+CHARACTER CLASSES
+
+         [...]       positive character class
+         [^...]      negative character class
+         [x-y]       range (can be used for hex characters)
+         [[:xxx:]]   positive POSIX named set
+         [[:^xxx:]]  negative POSIX named set
+
+         alnum       alphanumeric
+         alpha       alphabetic
+         ascii       0-127
+         blank       space or tab
+         cntrl       control character
+         digit       decimal digit
+         graph       printing, excluding space
+         lower       lower case letter
+         print       printing, including space
+         punct       printing, excluding alphanumeric
+         space       white space
+         upper       upper case letter
+         word        same as \w
+         xdigit      hexadecimal digit
+
+       In  PCRE,  POSIX character set names recognize only ASCII characters by
+       default, but some of them use Unicode properties if  PCRE_UCP  is  set.
+       You can use \Q...\E inside a character class.
+
+
+QUANTIFIERS
+
+         ?           0 or 1, greedy
+         ?+          0 or 1, possessive
+         ??          0 or 1, lazy
+         *           0 or more, greedy
+         *+          0 or more, possessive
+         *?          0 or more, lazy
+         +           1 or more, greedy
+         ++          1 or more, possessive
+         +?          1 or more, lazy
+         {n}         exactly n
+         {n,m}       at least n, no more than m, greedy
+         {n,m}+      at least n, no more than m, possessive
+         {n,m}?      at least n, no more than m, lazy
+         {n,}        n or more, greedy
+         {n,}+       n or more, possessive
+         {n,}?       n or more, lazy
+
+
+ANCHORS AND SIMPLE ASSERTIONS
+
+         \b          word boundary
+         \B          not a word boundary
+         ^           start of subject
+                      also after internal newline in multiline mode
+         \A          start of subject
+         $           end of subject
+                      also before newline at end of subject
+                      also before internal newline in multiline mode
+         \Z          end of subject
+                      also before newline at end of subject
+         \z          end of subject
+         \G          first matching position in subject
+
+
+MATCH POINT RESET
+
+         \K          reset start of match
+
+       \K is honoured in positive assertions, but ignored in negative ones.
+
+
+ALTERNATION
+
+         expr|expr|expr...
+
+
+CAPTURING
+
+         (...)           capturing group
+         (?<name>...)    named capturing group (Perl)
+         (?'name'...)    named capturing group (Perl)
+         (?P<name>...)   named capturing group (Python)
+         (?:...)         non-capturing group
+         (?|...)         non-capturing group; reset group numbers for
+                          capturing groups in each alternative
+
+
+ATOMIC GROUPS
+
+         (?>...)         atomic, non-capturing group
+
+
+COMMENT
+
+         (?#....)        comment (not nestable)
+
+
+OPTION SETTING
+
+         (?i)            caseless
+         (?J)            allow duplicate names
+         (?m)            multiline
+         (?s)            single line (dotall)
+         (?U)            default ungreedy (lazy)
+         (?x)            extended (ignore white space)
+         (?-...)         unset option(s)
+
+       The  following  are  recognized  only at the very start of a pattern or
+       after one of the newline or \R options with similar syntax.  More  than
+       one of them may appear.
+
+         (*LIMIT_MATCH=d) set the match limit to d (decimal number)
+         (*LIMIT_RECURSION=d) set the recursion limit to d (decimal number)
+         (*NO_AUTO_POSSESS) no auto-possessification (PCRE_NO_AUTO_POSSESS)
+         (*NO_START_OPT) no start-match optimization (PCRE_NO_START_OPTIMIZE)
+         (*UTF8)         set UTF-8 mode: 8-bit library (PCRE_UTF8)
+         (*UTF16)        set UTF-16 mode: 16-bit library (PCRE_UTF16)
+         (*UTF32)        set UTF-32 mode: 32-bit library (PCRE_UTF32)
+         (*UTF)          set appropriate UTF mode for the library in use
+         (*UCP)          set PCRE_UCP (use Unicode properties for \d etc)
+
+       Note  that LIMIT_MATCH and LIMIT_RECURSION can only reduce the value of
+       the limits set by the caller of pcre_exec(), not increase them.
+
+
+NEWLINE CONVENTION
+
+       These are recognized only at the very start of  the  pattern  or  after
+       option settings with a similar syntax.
+
+         (*CR)           carriage return only
+         (*LF)           linefeed only
+         (*CRLF)         carriage return followed by linefeed
+         (*ANYCRLF)      all three of the above
+         (*ANY)          any Unicode newline sequence
+
+
+WHAT \R MATCHES
+
+       These  are  recognized  only  at the very start of the pattern or after
+       option setting with a similar syntax.
+
+         (*BSR_ANYCRLF)  CR, LF, or CRLF
+         (*BSR_UNICODE)  any Unicode newline sequence
+
+
+LOOKAHEAD AND LOOKBEHIND ASSERTIONS
+
+         (?=...)         positive look ahead
+         (?!...)         negative look ahead
+         (?<=...)        positive look behind
+         (?<!...)        negative look behind
+
+       Each top-level branch of a look behind must be of a fixed length.
+
+
+BACKREFERENCES
+
+         \n              reference by number (can be ambiguous)
+         \gn             reference by number
+         \g{n}           reference by number
+         \g{-n}          relative reference by number
+         \k<name>        reference by name (Perl)
+         \k'name'        reference by name (Perl)
+         \g{name}        reference by name (Perl)
+         \k{name}        reference by name (.NET)
+         (?P=name)       reference by name (Python)
+
+
+SUBROUTINE REFERENCES (POSSIBLY RECURSIVE)
+
+         (?R)            recurse whole pattern
+         (?n)            call subpattern by absolute number
+         (?+n)           call subpattern by relative number
+         (?-n)           call subpattern by relative number
+         (?&name)        call subpattern by name (Perl)
+         (?P>name)       call subpattern by name (Python)
+         \g<name>        call subpattern by name (Oniguruma)
+         \g'name'        call subpattern by name (Oniguruma)
+         \g<n>           call subpattern by absolute number (Oniguruma)
+         \g'n'           call subpattern by absolute number (Oniguruma)
+         \g<+n>          call subpattern by relative number (PCRE extension)
+         \g'+n'          call subpattern by relative number (PCRE extension)
+         \g<-n>          call subpattern by relative number (PCRE extension)
+         \g'-n'          call subpattern by relative number (PCRE extension)
+
+
+CONDITIONAL PATTERNS
+
+         (?(condition)yes-pattern)
+         (?(condition)yes-pattern|no-pattern)
+
+         (?(n)...        absolute reference condition
+         (?(+n)...       relative reference condition
+         (?(-n)...       relative reference condition
+         (?(<name>)...   named reference condition (Perl)
+         (?('name')...   named reference condition (Perl)
+         (?(name)...     named reference condition (PCRE)
+         (?(R)...        overall recursion condition
+         (?(Rn)...       specific group recursion condition
+         (?(R&name)...   specific recursion condition
+         (?(DEFINE)...   define subpattern for reference
+         (?(assert)...   assertion condition
+
+
+BACKTRACKING CONTROL
+
+       The following act immediately they are reached:
+
+         (*ACCEPT)       force successful match
+         (*FAIL)         force backtrack; synonym (*F)
+         (*MARK:NAME)    set name to be passed back; synonym (*:NAME)
+
+       The following act only when a subsequent match failure causes  a  back-
+       track to reach them. They all force a match failure, but they differ in
+       what happens afterwards. Those that advance the start-of-match point do
+       so only if the pattern is not anchored.
+
+         (*COMMIT)       overall failure, no advance of starting point
+         (*PRUNE)        advance to next starting character
+         (*PRUNE:NAME)   equivalent to (*MARK:NAME)(*PRUNE)
+         (*SKIP)         advance to current matching position
+         (*SKIP:NAME)    advance to position corresponding to an earlier
+                         (*MARK:NAME); if not found, the (*SKIP) is ignored
+         (*THEN)         local failure, backtrack to next alternation
+         (*THEN:NAME)    equivalent to (*MARK:NAME)(*THEN)
+
+
+CALLOUTS
+
+         (?C)      callout
+         (?Cn)     callout with data n
+
+
+SEE ALSO
+
+       pcrepattern(3), pcreapi(3), pcrecallout(3), pcrematching(3), pcre(3).
+
+
+AUTHOR
+
+       Philip Hazel
+       University Computing Service
+       Cambridge CB2 3QH, England.
+
+
+REVISION
+
+       Last updated: 08 January 2014
+       Copyright (c) 1997-2014 University of Cambridge.
+------------------------------------------------------------------------------
+
+
+PCREUNICODE(3)             Library Functions Manual             PCREUNICODE(3)
+
+
+
+NAME
+       PCRE - Perl-compatible regular expressions
+
+UTF-8, UTF-16, UTF-32, AND UNICODE PROPERTY SUPPORT
+
+       As well as UTF-8 support, PCRE also supports UTF-16 (from release 8.30)
+       and UTF-32 (from release 8.32), by means of two  additional  libraries.
+       They can be built as well as, or instead of, the 8-bit library.
+
+
+UTF-8 SUPPORT
+
+       In  order  process  UTF-8  strings, you must build PCRE's 8-bit library
+       with UTF support, and, in addition, you must call  pcre_compile()  with
+       the  PCRE_UTF8 option flag, or the pattern must start with the sequence
+       (*UTF8) or (*UTF). When either of these is the case, both  the  pattern
+       and  any  subject  strings  that  are matched against it are treated as
+       UTF-8 strings instead of strings of individual 1-byte characters.
+
+
+UTF-16 AND UTF-32 SUPPORT
+
+       In order process UTF-16 or UTF-32 strings, you must build PCRE's 16-bit
+       or  32-bit  library  with  UTF support, and, in addition, you must call
+       pcre16_compile() or pcre32_compile() with the PCRE_UTF16 or  PCRE_UTF32
+       option flag, as appropriate. Alternatively, the pattern must start with
+       the sequence (*UTF16), (*UTF32), as appropriate, or (*UTF),  which  can
+       be used with either library. When UTF mode is set, both the pattern and
+       any subject strings that are matched against it are treated  as  UTF-16
+       or  UTF-32  strings  instead  of strings of individual 16-bit or 32-bit
+       characters.
+
+
+UTF SUPPORT OVERHEAD
+
+       If you compile PCRE with UTF support, but do not use it  at  run  time,
+       the  library will be a bit bigger, but the additional run time overhead
+       is limited to  testing  the  PCRE_UTF[8|16|32]  flag  occasionally,  so
+       should not be very big.
+
+
+UNICODE PROPERTY SUPPORT
+
+       If PCRE is built with Unicode character property support (which implies
+       UTF support), the escape sequences \p{..}, \P{..}, and \X can be  used.
+       The  available properties that can be tested are limited to the general
+       category properties such as Lu for an upper case letter  or  Nd  for  a
+       decimal number, the Unicode script names such as Arabic or Han, and the
+       derived properties Any and L&. Full lists is given in  the  pcrepattern
+       and  pcresyntax  documentation. Only the short names for properties are
+       supported. For example, \p{L}  matches  a  letter.  Its  Perl  synonym,
+       \p{Letter},  is  not  supported.  Furthermore, in Perl, many properties
+       may optionally be prefixed by "Is", for compatibility  with  Perl  5.6.
+       PCRE does not support this.
+
+   Validity of UTF-8 strings
+
+       When  you  set  the PCRE_UTF8 flag, the byte strings passed as patterns
+       and subjects are (by default) checked for validity on entry to the rel-
+       evant functions. The entire string is checked before any other process-
+       ing takes place. From release 7.3 of PCRE, the check is  according  the
+       rules of RFC 3629, which are themselves derived from the Unicode speci-
+       fication. Earlier releases of PCRE followed  the  rules  of  RFC  2279,
+       which  allows  the  full  range of 31-bit values (0 to 0x7FFFFFFF). The
+       current check allows only values in the range U+0 to U+10FFFF,  exclud-
+       ing  the  surrogate area. (From release 8.33 the so-called "non-charac-
+       ter" code points are no longer excluded because Unicode corrigendum  #9
+       makes it clear that they should not be.)
+
+       Characters  in  the "Surrogate Area" of Unicode are reserved for use by
+       UTF-16, where they are used in pairs to encode codepoints  with  values
+       greater  than  0xFFFF. The code points that are encoded by UTF-16 pairs
+       are available independently in the  UTF-8  and  UTF-32  encodings.  (In
+       other  words,  the  whole  surrogate  thing is a fudge for UTF-16 which
+       unfortunately messes up UTF-8 and UTF-32.)
+
+       If an invalid UTF-8 string is passed to PCRE, an error return is given.
+       At  compile  time, the only additional information is the offset to the
+       first byte of the failing character. The run-time functions pcre_exec()
+       and  pcre_dfa_exec() also pass back this information, as well as a more
+       detailed reason code if the caller has provided memory in which  to  do
+       this.
+
+       In  some  situations, you may already know that your strings are valid,
+       and therefore want to skip these checks in  order  to  improve  perfor-
+       mance,  for  example in the case of a long subject string that is being
+       scanned repeatedly.  If you set the PCRE_NO_UTF8_CHECK flag at  compile
+       time  or  at  run  time, PCRE assumes that the pattern or subject it is
+       given (respectively) contains only valid UTF-8 codes. In this case,  it
+       does not diagnose an invalid UTF-8 string.
+
+       Note  that  passing  PCRE_NO_UTF8_CHECK to pcre_compile() just disables
+       the check for the pattern; it does not also apply to  subject  strings.
+       If  you  want  to  disable the check for a subject string you must pass
+       this option to pcre_exec() or pcre_dfa_exec().
+
+       If you pass an invalid UTF-8 string when PCRE_NO_UTF8_CHECK is set, the
+       result is undefined and your program may crash.
+
+   Validity of UTF-16 strings
+
+       When you set the PCRE_UTF16 flag, the strings of 16-bit data units that
+       are passed as patterns and subjects are (by default) checked for valid-
+       ity  on entry to the relevant functions. Values other than those in the
+       surrogate range U+D800 to U+DFFF are independent code points. Values in
+       the surrogate range must be used in pairs in the correct manner.
+
+       If  an  invalid  UTF-16  string  is  passed to PCRE, an error return is
+       given. At compile time, the only additional information is  the  offset
+       to the first data unit of the failing character. The run-time functions
+       pcre16_exec() and pcre16_dfa_exec() also pass back this information, as
+       well  as  a more detailed reason code if the caller has provided memory
+       in which to do this.
+
+       In some situations, you may already know that your strings  are  valid,
+       and  therefore  want  to  skip these checks in order to improve perfor-
+       mance. If you set the PCRE_NO_UTF16_CHECK flag at compile  time  or  at
+       run time, PCRE assumes that the pattern or subject it is given (respec-
+       tively) contains only valid UTF-16 sequences. In this case, it does not
+       diagnose  an  invalid  UTF-16 string.  However, if an invalid string is
+       passed, the result is undefined.
+
+   Validity of UTF-32 strings
+
+       When you set the PCRE_UTF32 flag, the strings of 32-bit data units that
+       are passed as patterns and subjects are (by default) checked for valid-
+       ity on entry to the relevant functions.  This check allows only  values
+       in  the  range  U+0 to U+10FFFF, excluding the surrogate area U+D800 to
+       U+DFFF.
+
+       If an invalid UTF-32 string is passed  to  PCRE,  an  error  return  is
+       given.  At  compile time, the only additional information is the offset
+       to the first data unit of the failing character. The run-time functions
+       pcre32_exec() and pcre32_dfa_exec() also pass back this information, as
+       well as a more detailed reason code if the caller has  provided  memory
+       in which to do this.
+
+       In  some  situations, you may already know that your strings are valid,
+       and therefore want to skip these checks in  order  to  improve  perfor-
+       mance.  If  you  set the PCRE_NO_UTF32_CHECK flag at compile time or at
+       run time, PCRE assumes that the pattern or subject it is given (respec-
+       tively) contains only valid UTF-32 sequences. In this case, it does not
+       diagnose an invalid UTF-32 string.  However, if an  invalid  string  is
+       passed, the result is undefined.
+
+   General comments about UTF modes
+
+       1.  Codepoints  less  than  256  can be specified in patterns by either
+       braced or unbraced hexadecimal escape sequences (for example, \x{b3} or
+       \xb3). Larger values have to use braced sequences.
+
+       2.  Octal  numbers  up  to  \777 are recognized, and in UTF-8 mode they
+       match two-byte characters for values greater than \177.
+
+       3. Repeat quantifiers apply to complete UTF characters, not to individ-
+       ual data units, for example: \x{100}{3}.
+
+       4.  The dot metacharacter matches one UTF character instead of a single
+       data unit.
+
+       5. The escape sequence \C can be used to match a single byte  in  UTF-8
+       mode,  or  a single 16-bit data unit in UTF-16 mode, or a single 32-bit
+       data unit in UTF-32 mode, but its use can lead to some strange  effects
+       because  it  breaks up multi-unit characters (see the description of \C
+       in the pcrepattern documentation). The use of \C is  not  supported  in
+       the  alternative  matching  function  pcre[16|32]_dfa_exec(), nor is it
+       supported in UTF mode by the JIT optimization of pcre[16|32]_exec(). If
+       JIT  optimization  is  requested for a UTF pattern that contains \C, it
+       will not succeed, and so the matching will be carried out by the normal
+       interpretive function.
+
+       6.  The  character escapes \b, \B, \d, \D, \s, \S, \w, and \W correctly
+       test characters of any code value, but, by default, the characters that
+       PCRE  recognizes  as digits, spaces, or word characters remain the same
+       set as in non-UTF mode, all with values less  than  256.  This  remains
+       true  even  when  PCRE  is  built  to include Unicode property support,
+       because to do otherwise would slow down PCRE in many common cases. Note
+       in  particular that this applies to \b and \B, because they are defined
+       in terms of \w and \W. If you really want to test for a wider sense of,
+       say,  "digit",  you  can  use  explicit  Unicode property tests such as
+       \p{Nd}. Alternatively, if you set the PCRE_UCP option, the way that the
+       character  escapes  work is changed so that Unicode properties are used
+       to determine which characters match. There are more details in the sec-
+       tion on generic character types in the pcrepattern documentation.
+
+       7.  Similarly,  characters that match the POSIX named character classes
+       are all low-valued characters, unless the PCRE_UCP option is set.
+
+       8. However, the horizontal and vertical white  space  matching  escapes
+       (\h,  \H,  \v, and \V) do match all the appropriate Unicode characters,
+       whether or not PCRE_UCP is set.
+
+       9. Case-insensitive matching applies only to  characters  whose  values
+       are  less than 128, unless PCRE is built with Unicode property support.
+       A few Unicode characters such as Greek sigma have more than  two  code-
+       points that are case-equivalent. Up to and including PCRE release 8.31,
+       only one-to-one case mappings were supported, but later releases  (with
+       Unicode  property  support) do treat as case-equivalent all versions of
+       characters such as Greek sigma.
+
+
+AUTHOR
+
+       Philip Hazel
+       University Computing Service
+       Cambridge CB2 3QH, England.
+
+
+REVISION
+
+       Last updated: 27 February 2013
+       Copyright (c) 1997-2013 University of Cambridge.
+------------------------------------------------------------------------------
+
+
+PCREJIT(3)                 Library Functions Manual                 PCREJIT(3)
+
+
+
+NAME
+       PCRE - Perl-compatible regular expressions
+
+PCRE JUST-IN-TIME COMPILER SUPPORT
+
+       Just-in-time  compiling  is a heavyweight optimization that can greatly
+       speed up pattern matching. However, it comes at the cost of extra  pro-
+       cessing before the match is performed. Therefore, it is of most benefit
+       when the same pattern is going to be matched many times. This does  not
+       necessarily  mean  many calls of a matching function; if the pattern is
+       not anchored, matching attempts may take place many  times  at  various
+       positions  in  the  subject, even for a single call.  Therefore, if the
+       subject string is very long, it may still pay to use  JIT  for  one-off
+       matches.
+
+       JIT  support  applies  only to the traditional Perl-compatible matching
+       function.  It does not apply when the DFA matching  function  is  being
+       used. The code for this support was written by Zoltan Herczeg.
+
+
+8-BIT, 16-BIT AND 32-BIT SUPPORT
+
+       JIT  support  is available for all of the 8-bit, 16-bit and 32-bit PCRE
+       libraries. To keep this documentation simple, only the 8-bit  interface
+       is described in what follows. If you are using the 16-bit library, sub-
+       stitute the  16-bit  functions  and  16-bit  structures  (for  example,
+       pcre16_jit_stack  instead  of  pcre_jit_stack).  If  you  are using the
+       32-bit library, substitute the 32-bit functions and  32-bit  structures
+       (for example, pcre32_jit_stack instead of pcre_jit_stack).
+
+
+AVAILABILITY OF JIT SUPPORT
+
+       JIT  support  is  an  optional  feature of PCRE. The "configure" option
+       --enable-jit (or equivalent CMake option) must  be  set  when  PCRE  is
+       built  if  you want to use JIT. The support is limited to the following
+       hardware platforms:
+
+         ARM v5, v7, and Thumb2
+         Intel x86 32-bit and 64-bit
+         MIPS 32-bit
+         Power PC 32-bit and 64-bit
+         SPARC 32-bit (experimental)
+
+       If --enable-jit is set on an unsupported platform, compilation fails.
+
+       A program that is linked with PCRE 8.20 or later can tell if  JIT  sup-
+       port  is  available  by  calling pcre_config() with the PCRE_CONFIG_JIT
+       option. The result is 1 when JIT is available, and  0  otherwise.  How-
+       ever, a simple program does not need to check this in order to use JIT.
+       The normal API is implemented in a way that falls back to the interpre-
+       tive code if JIT is not available. For programs that need the best pos-
+       sible performance, there is also a "fast path"  API  that  is  JIT-spe-
+       cific.
+
+       If  your program may sometimes be linked with versions of PCRE that are
+       older than 8.20, but you want to use JIT when it is available, you  can
+       test the values of PCRE_MAJOR and PCRE_MINOR, or the existence of a JIT
+       macro such as PCRE_CONFIG_JIT, for compile-time control of your code.
+
+
+SIMPLE USE OF JIT
+
+       You have to do two things to make use of the JIT support  in  the  sim-
+       plest way:
+
+         (1) Call pcre_study() with the PCRE_STUDY_JIT_COMPILE option for
+             each compiled pattern, and pass the resulting pcre_extra block to
+             pcre_exec().
+
+         (2) Use pcre_free_study() to free the pcre_extra block when it is
+             no  longer  needed,  instead  of  just  freeing it yourself. This
+       ensures that
+             any JIT data is also freed.
+
+       For a program that may be linked with pre-8.20 versions  of  PCRE,  you
+       can insert
+
+         #ifndef PCRE_STUDY_JIT_COMPILE
+         #define PCRE_STUDY_JIT_COMPILE 0
+         #endif
+
+       so  that  no  option  is passed to pcre_study(), and then use something
+       like this to free the study data:
+
+         #ifdef PCRE_CONFIG_JIT
+             pcre_free_study(study_ptr);
+         #else
+             pcre_free(study_ptr);
+         #endif
+
+       PCRE_STUDY_JIT_COMPILE requests the JIT compiler to generate  code  for
+       complete  matches.  If  you  want  to  run  partial  matches  using the
+       PCRE_PARTIAL_HARD or  PCRE_PARTIAL_SOFT  options  of  pcre_exec(),  you
+       should  set  one  or  both  of the following options in addition to, or
+       instead of, PCRE_STUDY_JIT_COMPILE when you call pcre_study():
+
+         PCRE_STUDY_JIT_PARTIAL_HARD_COMPILE
+         PCRE_STUDY_JIT_PARTIAL_SOFT_COMPILE
+
+       The JIT compiler generates different optimized code  for  each  of  the
+       three  modes  (normal, soft partial, hard partial). When pcre_exec() is
+       called, the appropriate code is run if it is available. Otherwise,  the
+       pattern is matched using interpretive code.
+
+       In  some circumstances you may need to call additional functions. These
+       are described in the  section  entitled  "Controlling  the  JIT  stack"
+       below.
+
+       If  JIT  support  is  not  available,  PCRE_STUDY_JIT_COMPILE  etc. are
+       ignored, and no JIT data is created. Otherwise, the compiled pattern is
+       passed  to the JIT compiler, which turns it into machine code that exe-
+       cutes much faster than the normal interpretive code.  When  pcre_exec()
+       is  passed  a  pcre_extra block containing a pointer to JIT code of the
+       appropriate mode (normal or hard/soft  partial),  it  obeys  that  code
+       instead  of  running  the interpreter. The result is identical, but the
+       compiled JIT code runs much faster.
+
+       There are some pcre_exec() options that are not supported for JIT  exe-
+       cution.  There  are  also  some  pattern  items that JIT cannot handle.
+       Details are given below. In both cases, execution  automatically  falls
+       back  to  the  interpretive  code.  If you want to know whether JIT was
+       actually used for a particular match, you  should  arrange  for  a  JIT
+       callback  function  to  be  set up as described in the section entitled
+       "Controlling the JIT stack" below, even if you do not need to supply  a
+       non-default  JIT stack. Such a callback function is called whenever JIT
+       code is about to be obeyed. If the execution options are not right  for
+       JIT execution, the callback function is not obeyed.
+
+       If  the  JIT  compiler finds an unsupported item, no JIT data is gener-
+       ated. You can find out if JIT execution is available after  studying  a
+       pattern  by  calling  pcre_fullinfo()  with the PCRE_INFO_JIT option. A
+       result of 1 means that JIT compilation was successful. A  result  of  0
+       means that JIT support is not available, or the pattern was not studied
+       with PCRE_STUDY_JIT_COMPILE etc., or the JIT compiler was not  able  to
+       handle the pattern.
+
+       Once a pattern has been studied, with or without JIT, it can be used as
+       many times as you like for matching different subject strings.
+
+
+UNSUPPORTED OPTIONS AND PATTERN ITEMS
+
+       The only pcre_exec() options that are supported for JIT  execution  are
+       PCRE_NO_UTF8_CHECK, PCRE_NO_UTF16_CHECK, PCRE_NO_UTF32_CHECK, PCRE_NOT-
+       BOL,  PCRE_NOTEOL,  PCRE_NOTEMPTY,   PCRE_NOTEMPTY_ATSTART,   PCRE_PAR-
+       TIAL_HARD, and PCRE_PARTIAL_SOFT.
+
+       The  only  unsupported  pattern items are \C (match a single data unit)
+       when running in a UTF mode, and a callout immediately before an  asser-
+       tion condition in a conditional group.
+
+
+RETURN VALUES FROM JIT EXECUTION
+
+       When  a  pattern  is matched using JIT execution, the return values are
+       the same as those given by the interpretive pcre_exec() code, with  the
+       addition  of  one new error code: PCRE_ERROR_JIT_STACKLIMIT. This means
+       that the memory used for the JIT stack was insufficient. See  "Control-
+       ling the JIT stack" below for a discussion of JIT stack usage. For com-
+       patibility with the interpretive pcre_exec() code, no  more  than  two-
+       thirds  of  the ovector argument is used for passing back captured sub-
+       strings.
+
+       The error code PCRE_ERROR_MATCHLIMIT is returned by  the  JIT  code  if
+       searching  a  very large pattern tree goes on for too long, as it is in
+       the same circumstance when JIT is not used, but the details of  exactly
+       what  is  counted are not the same. The PCRE_ERROR_RECURSIONLIMIT error
+       code is never returned by JIT execution.
+
+
+SAVING AND RESTORING COMPILED PATTERNS
+
+       The code that is generated by the  JIT  compiler  is  architecture-spe-
+       cific,  and  is also position dependent. For those reasons it cannot be
+       saved (in a file or database) and restored later like the bytecode  and
+       other  data  of  a compiled pattern. Saving and restoring compiled pat-
+       terns is not something many people do. More detail about this  facility
+       is  given in the pcreprecompile documentation. It should be possible to
+       run pcre_study() on a saved and restored pattern, and thereby  recreate
+       the  JIT  data, but because JIT compilation uses significant resources,
+       it is probably not worth doing this; you might as  well  recompile  the
+       original pattern.
+
+
+CONTROLLING THE JIT STACK
+
+       When the compiled JIT code runs, it needs a block of memory to use as a
+       stack.  By default, it uses 32K on the  machine  stack.  However,  some
+       large   or   complicated  patterns  need  more  than  this.  The  error
+       PCRE_ERROR_JIT_STACKLIMIT is given when  there  is  not  enough  stack.
+       Three  functions  are provided for managing blocks of memory for use as
+       JIT stacks. There is further discussion about the use of JIT stacks  in
+       the section entitled "JIT stack FAQ" below.
+
+       The  pcre_jit_stack_alloc() function creates a JIT stack. Its arguments
+       are a starting size and a maximum size, and it returns a pointer to  an
+       opaque  structure of type pcre_jit_stack, or NULL if there is an error.
+       The pcre_jit_stack_free() function can be used to free a stack that  is
+       no  longer  needed.  (For  the technically minded: the address space is
+       allocated by mmap or VirtualAlloc.)
+
+       JIT uses far less memory for recursion than the interpretive code,  and
+       a  maximum  stack size of 512K to 1M should be more than enough for any
+       pattern.
+
+       The pcre_assign_jit_stack() function specifies  which  stack  JIT  code
+       should use. Its arguments are as follows:
+
+         pcre_extra         *extra
+         pcre_jit_callback  callback
+         void               *data
+
+       The  extra  argument  must  be  the  result  of studying a pattern with
+       PCRE_STUDY_JIT_COMPILE etc. There are three cases for the values of the
+       other two options:
+
+         (1) If callback is NULL and data is NULL, an internal 32K block
+             on the machine stack is used.
+
+         (2) If callback is NULL and data is not NULL, data must be
+             a valid JIT stack, the result of calling pcre_jit_stack_alloc().
+
+         (3) If callback is not NULL, it must point to a function that is
+             called with data as an argument at the start of matching, in
+             order to set up a JIT stack. If the return from the callback
+             function is NULL, the internal 32K stack is used; otherwise the
+             return value must be a valid JIT stack, the result of calling
+             pcre_jit_stack_alloc().
+
+       A  callback function is obeyed whenever JIT code is about to be run; it
+       is not obeyed when pcre_exec() is called with options that  are  incom-
+       patible for JIT execution. A callback function can therefore be used to
+       determine whether a match operation was  executed  by  JIT  or  by  the
+       interpreter.
+
+       You may safely use the same JIT stack for more than one pattern (either
+       by assigning directly or by callback), as long as the patterns are  all
+       matched  sequentially in the same thread. In a multithread application,
+       if you do not specify a JIT stack, or if you assign or pass  back  NULL
+       from  a  callback, that is thread-safe, because each thread has its own
+       machine stack. However, if you assign  or  pass  back  a  non-NULL  JIT
+       stack,  this  must  be  a  different  stack for each thread so that the
+       application is thread-safe.
+
+       Strictly speaking, even more is allowed. You can assign the  same  non-
+       NULL  stack  to any number of patterns as long as they are not used for
+       matching by multiple threads at the same time.  For  example,  you  can
+       assign  the same stack to all compiled patterns, and use a global mutex
+       in the callback to wait until the stack is available for use.  However,
+       this is an inefficient solution, and not recommended.
+
+       This  is a suggestion for how a multithreaded program that needs to set
+       up non-default JIT stacks might operate:
+
+         During thread initalization
+           thread_local_var = pcre_jit_stack_alloc(...)
+
+         During thread exit
+           pcre_jit_stack_free(thread_local_var)
+
+         Use a one-line callback function
+           return thread_local_var
+
+       All the functions described in this section do nothing if  JIT  is  not
+       available,  and  pcre_assign_jit_stack()  does nothing unless the extra
+       argument is non-NULL and points to  a  pcre_extra  block  that  is  the
+       result of a successful study with PCRE_STUDY_JIT_COMPILE etc.
+
+
+JIT STACK FAQ
+
+       (1) Why do we need JIT stacks?
+
+       PCRE  (and JIT) is a recursive, depth-first engine, so it needs a stack
+       where the local data of the current node is pushed before checking  its
+       child nodes.  Allocating real machine stack on some platforms is diffi-
+       cult. For example, the stack chain needs to be updated every time if we
+       extend  the  stack  on  PowerPC.  Although it is possible, its updating
+       time overhead decreases performance. So we do the recursion in memory.
+
+       (2) Why don't we simply allocate blocks of memory with malloc()?
+
+       Modern operating systems have a  nice  feature:  they  can  reserve  an
+       address space instead of allocating memory. We can safely allocate mem-
+       ory pages inside this address space, so the stack  could  grow  without
+       moving memory data (this is important because of pointers). Thus we can
+       allocate 1M address space, and use only a single memory  page  (usually
+       4K)  if  that is enough. However, we can still grow up to 1M anytime if
+       needed.
+
+       (3) Who "owns" a JIT stack?
+
+       The owner of the stack is the user program, not the JIT studied pattern
+       or  anything else. The user program must ensure that if a stack is used
+       by pcre_exec(), (that is, it is assigned to the pattern currently  run-
+       ning), that stack must not be used by any other threads (to avoid over-
+       writing the same memory area). The best practice for multithreaded pro-
+       grams  is  to  allocate  a stack for each thread, and return this stack
+       through the JIT callback function.
+
+       (4) When should a JIT stack be freed?
+
+       You can free a JIT stack at any time, as long as it will not be used by
+       pcre_exec()  again.  When  you  assign  the  stack to a pattern, only a
+       pointer is set. There is no reference counting or any other magic.  You
+       can  free  the  patterns  and stacks in any order, anytime. Just do not
+       call pcre_exec() with a pattern pointing to an already freed stack,  as
+       that  will cause SEGFAULT. (Also, do not free a stack currently used by
+       pcre_exec() in another thread). You can also replace the  stack  for  a
+       pattern  at  any  time.  You  can  even  free the previous stack before
+       assigning a replacement.
+
+       (5) Should I allocate/free a  stack  every  time  before/after  calling
+       pcre_exec()?
+
+       No,  because  this  is  too  costly in terms of resources. However, you
+       could implement some clever idea which release the stack if it  is  not
+       used  in  let's  say  two minutes. The JIT callback can help to achieve
+       this without keeping a list of the currently JIT studied patterns.
+
+       (6) OK, the stack is for long term memory allocation. But what  happens
+       if  a pattern causes stack overflow with a stack of 1M? Is that 1M kept
+       until the stack is freed?
+
+       Especially on embedded sytems, it might be a good idea to release  mem-
+       ory  sometimes  without  freeing the stack. There is no API for this at
+       the moment.  Probably a function call which returns with the  currently
+       allocated  memory for any stack and another which allows releasing mem-
+       ory (shrinking the stack) would be a good idea if someone needs this.
+
+       (7) This is too much of a headache. Isn't there any better solution for
+       JIT stack handling?
+
+       No,  thanks to Windows. If POSIX threads were used everywhere, we could
+       throw out this complicated API.
+
+
+EXAMPLE CODE
+
+       This is a single-threaded example that specifies a  JIT  stack  without
+       using a callback.
+
+         int rc;
+         int ovector[30];
+         pcre *re;
+         pcre_extra *extra;
+         pcre_jit_stack *jit_stack;
+
+         re = pcre_compile(pattern, 0, &error, &erroffset, NULL);
+         /* Check for errors */
+         extra = pcre_study(re, PCRE_STUDY_JIT_COMPILE, &error);
+         jit_stack = pcre_jit_stack_alloc(32*1024, 512*1024);
+         /* Check for error (NULL) */
+         pcre_assign_jit_stack(extra, NULL, jit_stack);
+         rc = pcre_exec(re, extra, subject, length, 0, 0, ovector, 30);
+         /* Check results */
+         pcre_free(re);
+         pcre_free_study(extra);
+         pcre_jit_stack_free(jit_stack);
+
+
+JIT FAST PATH API
+
+       Because  the  API  described  above falls back to interpreted execution
+       when JIT is not available, it is convenient for programs that are writ-
+       ten  for  general  use  in  many environments. However, calling JIT via
+       pcre_exec() does have a performance impact. Programs that  are  written
+       for  use  where  JIT  is known to be available, and which need the best
+       possible performance, can instead use a "fast path"  API  to  call  JIT
+       execution  directly  instead of calling pcre_exec() (obviously only for
+       patterns that have been successfully studied by JIT).
+
+       The fast path function is called pcre_jit_exec(), and it takes  exactly
+       the  same  arguments  as pcre_exec(), plus one additional argument that
+       must point to a JIT stack. The JIT stack arrangements  described  above
+       do not apply. The return values are the same as for pcre_exec().
+
+       When  you  call  pcre_exec(), as well as testing for invalid options, a
+       number of other sanity checks are performed on the arguments. For exam-
+       ple,  if  the  subject  pointer  is NULL, or its length is negative, an
+       immediate error is given. Also, unless PCRE_NO_UTF[8|16|32] is  set,  a
+       UTF  subject  string is tested for validity. In the interests of speed,
+       these checks do not happen on the JIT fast path, and if invalid data is
+       passed, the result is undefined.
+
+       Bypassing  the  sanity  checks  and  the  pcre_exec() wrapping can give
+       speedups of more than 10%.
+
+
+SEE ALSO
+
+       pcreapi(3)
+
+
+AUTHOR
+
+       Philip Hazel (FAQ by Zoltan Herczeg)
+       University Computing Service
+       Cambridge CB2 3QH, England.
+
+
+REVISION
+
+       Last updated: 17 March 2013
+       Copyright (c) 1997-2013 University of Cambridge.
+------------------------------------------------------------------------------
+
+
+PCREPARTIAL(3)             Library Functions Manual             PCREPARTIAL(3)
+
+
+
+NAME
+       PCRE - Perl-compatible regular expressions
+
+PARTIAL MATCHING IN PCRE
+
+       In normal use of PCRE, if the subject string that is passed to a match-
+       ing function matches as far as it goes, but is too short to  match  the
+       entire pattern, PCRE_ERROR_NOMATCH is returned. There are circumstances
+       where it might be helpful to distinguish this case from other cases  in
+       which there is no match.
+
+       Consider, for example, an application where a human is required to type
+       in data for a field with specific formatting requirements.  An  example
+       might be a date in the form ddmmmyy, defined by this pattern:
+
+         ^\d?\d(jan|feb|mar|apr|may|jun|jul|aug|sep|oct|nov|dec)\d\d$
+
+       If the application sees the user's keystrokes one by one, and can check
+       that what has been typed so far is potentially valid,  it  is  able  to
+       raise  an  error  as  soon  as  a  mistake  is made, by beeping and not
+       reflecting the character that has been typed, for example. This immedi-
+       ate  feedback is likely to be a better user interface than a check that
+       is delayed until the entire string has been entered.  Partial  matching
+       can  also be useful when the subject string is very long and is not all
+       available at once.
+
+       PCRE supports partial matching by means of  the  PCRE_PARTIAL_SOFT  and
+       PCRE_PARTIAL_HARD  options,  which  can  be set when calling any of the
+       matching functions. For backwards compatibility, PCRE_PARTIAL is a syn-
+       onym  for  PCRE_PARTIAL_SOFT.  The essential difference between the two
+       options is whether or not a partial match is preferred to  an  alterna-
+       tive complete match, though the details differ between the two types of
+       matching function. If both options  are  set,  PCRE_PARTIAL_HARD  takes
+       precedence.
+
+       If  you  want to use partial matching with just-in-time optimized code,
+       you must call pcre_study(), pcre16_study() or  pcre32_study() with  one
+       or both of these options:
+
+         PCRE_STUDY_JIT_PARTIAL_SOFT_COMPILE
+         PCRE_STUDY_JIT_PARTIAL_HARD_COMPILE
+
+       PCRE_STUDY_JIT_COMPILE  should also be set if you are going to run non-
+       partial matches on the same pattern. If the appropriate JIT study  mode
+       has not been set for a match, the interpretive matching code is used.
+
+       Setting a partial matching option disables two of PCRE's standard opti-
+       mizations. PCRE remembers the last literal data unit in a pattern,  and
+       abandons  matching  immediately  if  it  is  not present in the subject
+       string. This optimization cannot be used  for  a  subject  string  that
+       might  match only partially. If the pattern was studied, PCRE knows the
+       minimum length of a matching string, and does not  bother  to  run  the
+       matching  function  on  shorter strings. This optimization is also dis-
+       abled for partial matching.
+
+
+PARTIAL MATCHING USING pcre_exec() OR pcre[16|32]_exec()
+
+       A  partial   match   occurs   during   a   call   to   pcre_exec()   or
+       pcre[16|32]_exec()  when  the end of the subject string is reached suc-
+       cessfully, but matching cannot continue  because  more  characters  are
+       needed.   However, at least one character in the subject must have been
+       inspected. This character need not  form  part  of  the  final  matched
+       string;  lookbehind  assertions and the \K escape sequence provide ways
+       of inspecting characters before the start of a matched  substring.  The
+       requirement  for  inspecting  at  least one character exists because an
+       empty string can always be matched; without such  a  restriction  there
+       would  always  be  a partial match of an empty string at the end of the
+       subject.
+
+       If there are at least two slots in the offsets vector  when  a  partial
+       match  is returned, the first slot is set to the offset of the earliest
+       character that was inspected. For convenience, the second offset points
+       to the end of the subject so that a substring can easily be identified.
+       If there are at least three slots in the offsets vector, the third slot
+       is set to the offset of the character where matching started.
+
+       For the majority of patterns, the contents of the first and third slots
+       will be the same. However, for patterns that contain lookbehind  asser-
+       tions, or begin with \b or \B, characters before the one where matching
+       started may have been inspected while carrying out the match. For exam-
+       ple, consider this pattern:
+
+         /(?<=abc)123/
+
+       This pattern matches "123", but only if it is preceded by "abc". If the
+       subject string is "xyzabc12", the first two  offsets  after  a  partial
+       match  are for the substring "abc12", because all these characters were
+       inspected. However, the third offset is set to 6, because that  is  the
+       offset where matching began.
+
+       What happens when a partial match is identified depends on which of the
+       two partial matching options are set.
+
+   PCRE_PARTIAL_SOFT WITH pcre_exec() OR pcre[16|32]_exec()
+
+       If PCRE_PARTIAL_SOFT is  set  when  pcre_exec()  or  pcre[16|32]_exec()
+       identifies a partial match, the partial match is remembered, but match-
+       ing continues as normal, and other  alternatives  in  the  pattern  are
+       tried.  If  no  complete  match  can  be  found,  PCRE_ERROR_PARTIAL is
+       returned instead of PCRE_ERROR_NOMATCH.
+
+       This option is "soft" because it prefers a complete match over  a  par-
+       tial  match.   All the various matching items in a pattern behave as if
+       the subject string is potentially complete. For example, \z, \Z, and  $
+       match  at  the end of the subject, as normal, and for \b and \B the end
+       of the subject is treated as a non-alphanumeric.
+
+       If there is more than one partial match, the first one that  was  found
+       provides the data that is returned. Consider this pattern:
+
+         /123\w+X|dogY/
+
+       If  this is matched against the subject string "abc123dog", both alter-
+       natives fail to match, but the end of the  subject  is  reached  during
+       matching,  so  PCRE_ERROR_PARTIAL is returned. The offsets are set to 3
+       and 9, identifying "123dog" as the first partial match that was  found.
+       (In  this  example, there are two partial matches, because "dog" on its
+       own partially matches the second alternative.)
+
+   PCRE_PARTIAL_HARD WITH pcre_exec() OR pcre[16|32]_exec()
+
+       If PCRE_PARTIAL_HARD is  set  for  pcre_exec()  or  pcre[16|32]_exec(),
+       PCRE_ERROR_PARTIAL  is  returned  as  soon as a partial match is found,
+       without continuing to search for possible complete matches. This option
+       is "hard" because it prefers an earlier partial match over a later com-
+       plete match. For this reason, the assumption is made that  the  end  of
+       the  supplied  subject  string may not be the true end of the available
+       data, and so, if \z, \Z, \b, \B, or $ are encountered at the end of the
+       subject,  the  result is PCRE_ERROR_PARTIAL, provided that at least one
+       character in the subject has been inspected.
+
+       Setting PCRE_PARTIAL_HARD also affects the way UTF-8 and UTF-16 subject
+       strings  are checked for validity. Normally, an invalid sequence causes
+       the error PCRE_ERROR_BADUTF8 or PCRE_ERROR_BADUTF16.  However,  in  the
+       special  case  of  a  truncated  character  at  the end of the subject,
+       PCRE_ERROR_SHORTUTF8  or   PCRE_ERROR_SHORTUTF16   is   returned   when
+       PCRE_PARTIAL_HARD is set.
+
+   Comparing hard and soft partial matching
+
+       The  difference  between the two partial matching options can be illus-
+       trated by a pattern such as:
+
+         /dog(sbody)?/
+
+       This matches either "dog" or "dogsbody", greedily (that is, it  prefers
+       the  longer  string  if  possible). If it is matched against the string
+       "dog" with PCRE_PARTIAL_SOFT, it yields a  complete  match  for  "dog".
+       However, if PCRE_PARTIAL_HARD is set, the result is PCRE_ERROR_PARTIAL.
+       On the other hand, if the pattern is made ungreedy the result  is  dif-
+       ferent:
+
+         /dog(sbody)??/
+
+       In  this  case  the  result  is always a complete match because that is
+       found first, and matching never  continues  after  finding  a  complete
+       match. It might be easier to follow this explanation by thinking of the
+       two patterns like this:
+
+         /dog(sbody)?/    is the same as  /dogsbody|dog/
+         /dog(sbody)??/   is the same as  /dog|dogsbody/
+
+       The second pattern will never match "dogsbody", because it will  always
+       find the shorter match first.
+
+
+PARTIAL MATCHING USING pcre_dfa_exec() OR pcre[16|32]_dfa_exec()
+
+       The DFA functions move along the subject string character by character,
+       without backtracking, searching for  all  possible  matches  simultane-
+       ously.  If the end of the subject is reached before the end of the pat-
+       tern, there is the possibility of a partial match, again provided  that
+       at least one character has been inspected.
+
+       When  PCRE_PARTIAL_SOFT  is set, PCRE_ERROR_PARTIAL is returned only if
+       there have been no complete matches. Otherwise,  the  complete  matches
+       are  returned.   However,  if PCRE_PARTIAL_HARD is set, a partial match
+       takes precedence over any complete matches. The portion of  the  string
+       that  was  inspected when the longest partial match was found is set as
+       the first matching string, provided there are at least two slots in the
+       offsets vector.
+
+       Because  the  DFA functions always search for all possible matches, and
+       there is no difference between greedy and  ungreedy  repetition,  their
+       behaviour  is  different  from  the  standard  functions when PCRE_PAR-
+       TIAL_HARD is  set.  Consider  the  string  "dog"  matched  against  the
+       ungreedy pattern shown above:
+
+         /dog(sbody)??/
+
+       Whereas  the  standard functions stop as soon as they find the complete
+       match for "dog", the DFA functions also  find  the  partial  match  for
+       "dogsbody", and so return that when PCRE_PARTIAL_HARD is set.
+
+
+PARTIAL MATCHING AND WORD BOUNDARIES
+
+       If  a  pattern ends with one of sequences \b or \B, which test for word
+       boundaries, partial matching with PCRE_PARTIAL_SOFT can  give  counter-
+       intuitive results. Consider this pattern:
+
+         /\bcat\b/
+
+       This matches "cat", provided there is a word boundary at either end. If
+       the subject string is "the cat", the comparison of the final "t" with a
+       following  character  cannot  take  place, so a partial match is found.
+       However, normal matching carries on, and \b matches at the end  of  the
+       subject  when  the  last  character is a letter, so a complete match is
+       found.  The  result,  therefore,  is  not   PCRE_ERROR_PARTIAL.   Using
+       PCRE_PARTIAL_HARD  in  this case does yield PCRE_ERROR_PARTIAL, because
+       then the partial match takes precedence.
+
+
+FORMERLY RESTRICTED PATTERNS
+
+       For releases of PCRE prior to 8.00, because of the way certain internal
+       optimizations   were  implemented  in  the  pcre_exec()  function,  the
+       PCRE_PARTIAL option (predecessor of  PCRE_PARTIAL_SOFT)  could  not  be
+       used  with all patterns. From release 8.00 onwards, the restrictions no
+       longer apply, and partial matching with can be requested for  any  pat-
+       tern.
+
+       Items that were formerly restricted were repeated single characters and
+       repeated metasequences. If PCRE_PARTIAL was set for a pattern that  did
+       not  conform  to  the restrictions, pcre_exec() returned the error code
+       PCRE_ERROR_BADPARTIAL (-13). This error code is no longer in  use.  The
+       PCRE_INFO_OKPARTIAL  call  to pcre_fullinfo() to find out if a compiled
+       pattern can be used for partial matching now always returns 1.
+
+
+EXAMPLE OF PARTIAL MATCHING USING PCRETEST
+
+       If the escape sequence \P is present  in  a  pcretest  data  line,  the
+       PCRE_PARTIAL_SOFT  option  is  used  for  the  match.  Here is a run of
+       pcretest that uses the date example quoted above:
+
+           re> /^\d?\d(jan|feb|mar|apr|may|jun|jul|aug|sep|oct|nov|dec)\d\d$/
+         data> 25jun04\P
+          0: 25jun04
+          1: jun
+         data> 25dec3\P
+         Partial match: 23dec3
+         data> 3ju\P
+         Partial match: 3ju
+         data> 3juj\P
+         No match
+         data> j\P
+         No match
+
+       The first data string is matched  completely,  so  pcretest  shows  the
+       matched  substrings.  The  remaining four strings do not match the com-
+       plete pattern, but the first two are partial matches. Similar output is
+       obtained if DFA matching is used.
+
+       If  the escape sequence \P is present more than once in a pcretest data
+       line, the PCRE_PARTIAL_HARD option is set for the match.
+
+
+MULTI-SEGMENT MATCHING WITH pcre_dfa_exec() OR pcre[16|32]_dfa_exec()
+
+       When a partial match has been found using a DFA matching  function,  it
+       is  possible to continue the match by providing additional subject data
+       and calling the function again with the same compiled  regular  expres-
+       sion,  this time setting the PCRE_DFA_RESTART option. You must pass the
+       same working space as before, because this is where details of the pre-
+       vious  partial  match  are  stored.  Here is an example using pcretest,
+       using the \R escape sequence to set  the  PCRE_DFA_RESTART  option  (\D
+       specifies the use of the DFA matching function):
+
+           re> /^\d?\d(jan|feb|mar|apr|may|jun|jul|aug|sep|oct|nov|dec)\d\d$/
+         data> 23ja\P\D
+         Partial match: 23ja
+         data> n05\R\D
+          0: n05
+
+       The  first  call has "23ja" as the subject, and requests partial match-
+       ing; the second call  has  "n05"  as  the  subject  for  the  continued
+       (restarted)  match.   Notice  that when the match is complete, only the
+       last part is shown; PCRE does  not  retain  the  previously  partially-
+       matched  string. It is up to the calling program to do that if it needs
+       to.
+
+       That means that, for an unanchored pattern, if a continued match fails,
+       it  is  not  possible  to  try  again at a new starting point. All this
+       facility is capable of doing is  continuing  with  the  previous  match
+       attempt.  In  the previous example, if the second set of data is "ug23"
+       the result is no match, even though there would be a match for  "aug23"
+       if  the entire string were given at once. Depending on the application,
+       this may or may not be what you want.  The only way to allow for start-
+       ing  again  at  the next character is to retain the matched part of the
+       subject and try a new complete match.
+
+       You can set the PCRE_PARTIAL_SOFT  or  PCRE_PARTIAL_HARD  options  with
+       PCRE_DFA_RESTART  to  continue partial matching over multiple segments.
+       This facility can be used to pass very long subject strings to the  DFA
+       matching functions.
+
+
+MULTI-SEGMENT MATCHING WITH pcre_exec() OR pcre[16|32]_exec()
+
+       From  release 8.00, the standard matching functions can also be used to
+       do multi-segment matching. Unlike the DFA functions, it is not possible
+       to  restart the previous match with a new segment of data. Instead, new
+       data must be added to the previous subject string, and the entire match
+       re-run,  starting from the point where the partial match occurred. Ear-
+       lier data can be discarded.
+
+       It is best to use PCRE_PARTIAL_HARD in this situation, because it  does
+       not  treat the end of a segment as the end of the subject when matching
+       \z, \Z, \b, \B, and $. Consider  an  unanchored  pattern  that  matches
+       dates:
+
+           re> /\d?\d(jan|feb|mar|apr|may|jun|jul|aug|sep|oct|nov|dec)\d\d/
+         data> The date is 23ja\P\P
+         Partial match: 23ja
+
+       At  this stage, an application could discard the text preceding "23ja",
+       add on text from the next  segment,  and  call  the  matching  function
+       again.  Unlike  the  DFA matching functions, the entire matching string
+       must always be available, and the complete matching process occurs  for
+       each call, so more memory and more processing time is needed.
+
+       Note:  If  the pattern contains lookbehind assertions, or \K, or starts
+       with \b or \B, the string that is returned for a partial match includes
+       characters  that precede the start of what would be returned for a com-
+       plete match, because it contains all the characters that were inspected
+       during the partial match.
+
+
+ISSUES WITH MULTI-SEGMENT MATCHING
+
+       Certain types of pattern may give problems with multi-segment matching,
+       whichever matching function is used.
+
+       1. If the pattern contains a test for the beginning of a line, you need
+       to  pass  the  PCRE_NOTBOL  option when the subject string for any call
+       does start at the beginning of a line.  There  is  also  a  PCRE_NOTEOL
+       option, but in practice when doing multi-segment matching you should be
+       using PCRE_PARTIAL_HARD, which includes the effect of PCRE_NOTEOL.
+
+       2. Lookbehind assertions that have already been obeyed are catered  for
+       in the offsets that are returned for a partial match. However a lookbe-
+       hind assertion later in the pattern could require even earlier  charac-
+       ters   to  be  inspected.  You  can  handle  this  case  by  using  the
+       PCRE_INFO_MAXLOOKBEHIND    option    of    the    pcre_fullinfo()    or
+       pcre[16|32]_fullinfo()  functions  to  obtain the length of the longest
+       lookbehind in the pattern. This length  is  given  in  characters,  not
+       bytes.  If  you  always retain at least that many characters before the
+       partially matched string, all should be  well.  (Of  course,  near  the
+       start of the subject, fewer characters may be present; in that case all
+       characters should be retained.)
+
+       From release 8.33, there is a more accurate way of deciding which char-
+       acters  to  retain.  Instead  of  subtracting the length of the longest
+       lookbehind from the  earliest  inspected  character  (offsets[0]),  the
+       match  start  position  (offsets[2]) should be used, and the next match
+       attempt started at the offsets[2] character by setting the  startoffset
+       argument of pcre_exec() or pcre_dfa_exec().
+
+       For  example, if the pattern "(?<=123)abc" is partially matched against
+       the string "xx123a", the three offset values returned are 2, 6, and  5.
+       This  indicates  that  the  matching  process that gave a partial match
+       started at offset 5, but the characters "123a" were all inspected.  The
+       maximum  lookbehind  for  that pattern is 3, so taking that away from 5
+       shows that we need only keep "123a", and the next match attempt can  be
+       started at offset 3 (that is, at "a") when further characters have been
+       added. When the match start is not the  earliest  inspected  character,
+       pcretest shows it explicitly:
+
+           re> "(?<=123)abc"
+         data> xx123a\P\P
+         Partial match at offset 5: 123a
+
+       3.  Because a partial match must always contain at least one character,
+       what might be considered a partial match of an  empty  string  actually
+       gives a "no match" result. For example:
+
+           re> /c(?<=abc)x/
+         data> ab\P
+         No match
+
+       If the next segment begins "cx", a match should be found, but this will
+       only happen if characters from the previous segment are  retained.  For
+       this  reason,  a  "no  match"  result should be interpreted as "partial
+       match of an empty string" when the pattern contains lookbehinds.
+
+       4. Matching a subject string that is split into multiple  segments  may
+       not  always produce exactly the same result as matching over one single
+       long string, especially when PCRE_PARTIAL_SOFT  is  used.  The  section
+       "Partial  Matching  and  Word Boundaries" above describes an issue that
+       arises if the pattern ends with \b or \B. Another  kind  of  difference
+       may  occur when there are multiple matching possibilities, because (for
+       PCRE_PARTIAL_SOFT) a partial match result is given only when there  are
+       no completed matches. This means that as soon as the shortest match has
+       been found, continuation to a new subject segment is no  longer  possi-
+       ble. Consider again this pcretest example:
+
+           re> /dog(sbody)?/
+         data> dogsb\P
+          0: dog
+         data> do\P\D
+         Partial match: do
+         data> gsb\R\P\D
+          0: g
+         data> dogsbody\D
+          0: dogsbody
+          1: dog
+
+       The  first  data  line passes the string "dogsb" to a standard matching
+       function, setting the PCRE_PARTIAL_SOFT option. Although the string  is
+       a  partial  match for "dogsbody", the result is not PCRE_ERROR_PARTIAL,
+       because the shorter string "dog" is a complete match.  Similarly,  when
+       the  subject  is  presented to a DFA matching function in several parts
+       ("do" and "gsb" being the first two) the match  stops  when  "dog"  has
+       been  found, and it is not possible to continue.  On the other hand, if
+       "dogsbody" is presented as a single string,  a  DFA  matching  function
+       finds both matches.
+
+       Because  of  these  problems,  it is best to use PCRE_PARTIAL_HARD when
+       matching multi-segment data. The example  above  then  behaves  differ-
+       ently:
+
+           re> /dog(sbody)?/
+         data> dogsb\P\P
+         Partial match: dogsb
+         data> do\P\D
+         Partial match: do
+         data> gsb\R\P\P\D
+         Partial match: gsb
+
+       5. Patterns that contain alternatives at the top level which do not all
+       start with the  same  pattern  item  may  not  work  as  expected  when
+       PCRE_DFA_RESTART is used. For example, consider this pattern:
+
+         1234|3789
+
+       If  the  first  part of the subject is "ABC123", a partial match of the
+       first alternative is found at offset 3. There is no partial  match  for
+       the second alternative, because such a match does not start at the same
+       point in the subject string. Attempting to  continue  with  the  string
+       "7890"  does  not  yield  a  match because only those alternatives that
+       match at one point in the subject are remembered.  The  problem  arises
+       because  the  start  of the second alternative matches within the first
+       alternative. There is no problem with  anchored  patterns  or  patterns
+       such as:
+
+         1234|ABCD
+
+       where  no  string can be a partial match for both alternatives. This is
+       not a problem if a standard matching  function  is  used,  because  the
+       entire match has to be rerun each time:
+
+           re> /1234|3789/
+         data> ABC123\P\P
+         Partial match: 123
+         data> 1237890
+          0: 3789
+
+       Of course, instead of using PCRE_DFA_RESTART, the same technique of re-
+       running the entire match can also be used with the DFA  matching  func-
+       tions.  Another  possibility  is to work with two buffers. If a partial
+       match at offset n in the first buffer is followed by  "no  match"  when
+       PCRE_DFA_RESTART  is  used on the second buffer, you can then try a new
+       match starting at offset n+1 in the first buffer.
+
+
+AUTHOR
+
+       Philip Hazel
+       University Computing Service
+       Cambridge CB2 3QH, England.
+
+
+REVISION
+
+       Last updated: 02 July 2013
+       Copyright (c) 1997-2013 University of Cambridge.
+------------------------------------------------------------------------------
+
+
+PCREPRECOMPILE(3)          Library Functions Manual          PCREPRECOMPILE(3)
+
+
+
+NAME
+       PCRE - Perl-compatible regular expressions
+
+SAVING AND RE-USING PRECOMPILED PCRE PATTERNS
+
+       If  you  are running an application that uses a large number of regular
+       expression patterns, it may be useful to store them  in  a  precompiled
+       form  instead  of  having to compile them every time the application is
+       run.  If you are not  using  any  private  character  tables  (see  the
+       pcre_maketables()  documentation),  this is relatively straightforward.
+       If you are using private tables, it is a little bit  more  complicated.
+       However,  if you are using the just-in-time optimization feature, it is
+       not possible to save and reload the JIT data.
+
+       If you save compiled patterns to a file, you can copy them to a differ-
+       ent host and run them there. If the two hosts have different endianness
+       (byte    order),    you     should     run     the     pcre[16|32]_pat-
+       tern_to_host_byte_order()  function  on  the  new host before trying to
+       match the pattern. The matching functions return  PCRE_ERROR_BADENDIAN-
+       NESS if they detect a pattern with the wrong endianness.
+
+       Compiling  regular  expressions with one version of PCRE for use with a
+       different version is not guaranteed to work and may cause crashes,  and
+       saving  and  restoring  a  compiled  pattern loses any JIT optimization
+       data.
+
+
+SAVING A COMPILED PATTERN
+
+       The value returned by pcre[16|32]_compile() points to a single block of
+       memory  that  holds  the  compiled pattern and associated data. You can
+       find   the   length   of   this   block    in    bytes    by    calling
+       pcre[16|32]_fullinfo() with an argument of PCRE_INFO_SIZE. You can then
+       save the data in any appropriate manner. Here is sample  code  for  the
+       8-bit  library  that  compiles  a  pattern  and writes it to a file. It
+       assumes that the variable fd refers to a file that is open for output:
+
+         int erroroffset, rc, size;
+         char *error;
+         pcre *re;
+
+         re = pcre_compile("my pattern", 0, &error, &erroroffset, NULL);
+         if (re == NULL) { ... handle errors ... }
+         rc = pcre_fullinfo(re, NULL, PCRE_INFO_SIZE, &size);
+         if (rc < 0) { ... handle errors ... }
+         rc = fwrite(re, 1, size, fd);
+         if (rc != size) { ... handle errors ... }
+
+       In this example, the bytes  that  comprise  the  compiled  pattern  are
+       copied  exactly.  Note that this is binary data that may contain any of
+       the 256 possible byte  values.  On  systems  that  make  a  distinction
+       between binary and non-binary data, be sure that the file is opened for
+       binary output.
+
+       If you want to write more than one pattern to a file, you will have  to
+       devise  a  way of separating them. For binary data, preceding each pat-
+       tern with its length is probably  the  most  straightforward  approach.
+       Another  possibility is to write out the data in hexadecimal instead of
+       binary, one pattern to a line.
+
+       Saving compiled patterns in a file is only one possible way of  storing
+       them  for later use. They could equally well be saved in a database, or
+       in the memory of some daemon process that passes them  via  sockets  to
+       the processes that want them.
+
+       If the pattern has been studied, it is also possible to save the normal
+       study data in a similar way to the compiled pattern itself. However, if
+       the PCRE_STUDY_JIT_COMPILE was used, the just-in-time data that is cre-
+       ated cannot be saved because it is too dependent on the  current  envi-
+       ronment.    When    studying    generates    additional    information,
+       pcre[16|32]_study() returns  a  pointer  to  a  pcre[16|32]_extra  data
+       block.  Its  format  is defined in the section on matching a pattern in
+       the pcreapi documentation. The study_data field points  to  the  binary
+       study  data,  and this is what you must save (not the pcre[16|32]_extra
+       block itself). The length of the study data can be obtained by  calling
+       pcre[16|32]_fullinfo()  with an argument of PCRE_INFO_STUDYSIZE. Remem-
+       ber to check that  pcre[16|32]_study()  did  return  a  non-NULL  value
+       before trying to save the study data.
+
+
+RE-USING A PRECOMPILED PATTERN
+
+       Re-using  a  precompiled pattern is straightforward. Having reloaded it
+       into main memory,  called  pcre[16|32]_pattern_to_host_byte_order()  if
+       necessary,    you   pass   its   pointer   to   pcre[16|32]_exec()   or
+       pcre[16|32]_dfa_exec() in the usual way.
+
+       However, if you passed a pointer to custom character  tables  when  the
+       pattern  was compiled (the tableptr argument of pcre[16|32]_compile()),
+       you  must  now  pass  a  similar  pointer  to   pcre[16|32]_exec()   or
+       pcre[16|32]_dfa_exec(),  because the value saved with the compiled pat-
+       tern will obviously be nonsense. A field in a pcre[16|32]_extra() block
+       is  used  to  pass this data, as described in the section on matching a
+       pattern in the pcreapi documentation.
+
+       Warning: The tables that pcre_exec() and pcre_dfa_exec()  use  must  be
+       the same as those that were used when the pattern was compiled. If this
+       is not the case, the behaviour is undefined.
+
+       If you did not provide custom character tables  when  the  pattern  was
+       compiled, the pointer in the compiled pattern is NULL, which causes the
+       matching functions to use PCRE's internal tables. Thus, you do not need
+       to take any special action at run time in this case.
+
+       If  you  saved study data with the compiled pattern, you need to create
+       your own pcre[16|32]_extra data block and set the study_data  field  to
+       point   to   the   reloaded   study   data.   You  must  also  set  the
+       PCRE_EXTRA_STUDY_DATA bit in the flags field  to  indicate  that  study
+       data  is present. Then pass the pcre[16|32]_extra block to the matching
+       function in the usual way. If the pattern was studied for  just-in-time
+       optimization,  that  data  cannot  be  saved,  and  so  is  lost  by  a
+       save/restore cycle.
+
+
+COMPATIBILITY WITH DIFFERENT PCRE RELEASES
+
+       In general, it is safest to  recompile  all  saved  patterns  when  you
+       update  to  a new PCRE release, though not all updates actually require
+       this.
+
+
+AUTHOR
+
+       Philip Hazel
+       University Computing Service
+       Cambridge CB2 3QH, England.
+
+
+REVISION
+
+       Last updated: 12 November 2013
+       Copyright (c) 1997-2013 University of Cambridge.
+------------------------------------------------------------------------------
+
+
+PCREPERFORM(3)             Library Functions Manual             PCREPERFORM(3)
+
+
+
+NAME
+       PCRE - Perl-compatible regular expressions
+
+PCRE PERFORMANCE
+
+       Two  aspects  of performance are discussed below: memory usage and pro-
+       cessing time. The way you express your pattern as a regular  expression
+       can affect both of them.
+
+
+COMPILED PATTERN MEMORY USAGE
+
+       Patterns  are compiled by PCRE into a reasonably efficient interpretive
+       code, so that most simple patterns do not  use  much  memory.  However,
+       there  is  one case where the memory usage of a compiled pattern can be
+       unexpectedly large. If a parenthesized subpattern has a quantifier with
+       a minimum greater than 1 and/or a limited maximum, the whole subpattern
+       is repeated in the compiled code. For example, the pattern
+
+         (abc|def){2,4}
+
+       is compiled as if it were
+
+         (abc|def)(abc|def)((abc|def)(abc|def)?)?
+
+       (Technical aside: It is done this way so that backtrack  points  within
+       each of the repetitions can be independently maintained.)
+
+       For  regular expressions whose quantifiers use only small numbers, this
+       is not usually a problem. However, if the numbers are large,  and  par-
+       ticularly  if  such repetitions are nested, the memory usage can become
+       an embarrassment. For example, the very simple pattern
+
+         ((ab){1,1000}c){1,3}
+
+       uses 51K bytes when compiled using the 8-bit library. When PCRE is com-
+       piled  with  its  default  internal pointer size of two bytes, the size
+       limit on a compiled pattern is 64K data units, and this is reached with
+       the  above  pattern  if  the outer repetition is increased from 3 to 4.
+       PCRE can be compiled to use larger internal pointers  and  thus  handle
+       larger  compiled patterns, but it is better to try to rewrite your pat-
+       tern to use less memory if you can.
+
+       One way of reducing the memory usage for such patterns is to  make  use
+       of PCRE's "subroutine" facility. Re-writing the above pattern as
+
+         ((ab)(?2){0,999}c)(?1){0,2}
+
+       reduces the memory requirements to 18K, and indeed it remains under 20K
+       even with the outer repetition increased to 100. However, this  pattern
+       is  not  exactly equivalent, because the "subroutine" calls are treated
+       as atomic groups into which there can be no backtracking if there is  a
+       subsequent  matching  failure.  Therefore,  PCRE cannot do this kind of
+       rewriting automatically.  Furthermore, there is a  noticeable  loss  of
+       speed  when executing the modified pattern. Nevertheless, if the atomic
+       grouping is not a problem and the loss of  speed  is  acceptable,  this
+       kind  of  rewriting will allow you to process patterns that PCRE cannot
+       otherwise handle.
+
+
+STACK USAGE AT RUN TIME
+
+       When pcre_exec() or pcre[16|32]_exec() is used  for  matching,  certain
+       kinds  of  pattern  can  cause  it  to use large amounts of the process
+       stack. In some environments the default process stack is  quite  small,
+       and  if it runs out the result is often SIGSEGV. This issue is probably
+       the most frequently raised problem with PCRE.  Rewriting  your  pattern
+       can  often  help.  The  pcrestack documentation discusses this issue in
+       detail.
+
+
+PROCESSING TIME
+
+       Certain items in regular expression patterns are processed  more  effi-
+       ciently than others. It is more efficient to use a character class like
+       [aeiou]  than  a  set  of   single-character   alternatives   such   as
+       (a|e|i|o|u).  In  general,  the simplest construction that provides the
+       required behaviour is usually the most efficient. Jeffrey Friedl's book
+       contains  a  lot  of useful general discussion about optimizing regular
+       expressions for efficient performance. This  document  contains  a  few
+       observations about PCRE.
+
+       Using  Unicode  character  properties  (the  \p, \P, and \X escapes) is
+       slow, because PCRE has to use a multi-stage table  lookup  whenever  it
+       needs  a  character's  property. If you can find an alternative pattern
+       that does not use character properties, it will probably be faster.
+
+       By default, the escape sequences \b, \d, \s,  and  \w,  and  the  POSIX
+       character  classes  such  as  [:alpha:]  do not use Unicode properties,
+       partly for backwards compatibility, and partly for performance reasons.
+       However,  you can set PCRE_UCP if you want Unicode character properties
+       to be used. This can double the matching time for  items  such  as  \d,
+       when matched with a traditional matching function; the performance loss
+       is less with a DFA matching function, and in both cases  there  is  not
+       much difference for \b.
+
+       When  a  pattern  begins  with .* not in parentheses, or in parentheses
+       that are not the subject of a backreference, and the PCRE_DOTALL option
+       is  set, the pattern is implicitly anchored by PCRE, since it can match
+       only at the start of a subject string. However, if PCRE_DOTALL  is  not
+       set,  PCRE  cannot  make this optimization, because the . metacharacter
+       does not then match a newline, and if the subject string contains  new-
+       lines,  the  pattern may match from the character immediately following
+       one of them instead of from the very start. For example, the pattern
+
+         .*second
+
+       matches the subject "first\nand second" (where \n stands for a  newline
+       character),  with the match starting at the seventh character. In order
+       to do this, PCRE has to retry the match starting after every newline in
+       the subject.
+
+       If  you  are using such a pattern with subject strings that do not con-
+       tain newlines, the best performance is obtained by setting PCRE_DOTALL,
+       or  starting  the pattern with ^.* or ^.*? to indicate explicit anchor-
+       ing. That saves PCRE from having to scan along the subject looking  for
+       a newline to restart at.
+
+       Beware  of  patterns  that contain nested indefinite repeats. These can
+       take a long time to run when applied to a string that does  not  match.
+       Consider the pattern fragment
+
+         ^(a+)*
+
+       This  can  match "aaaa" in 16 different ways, and this number increases
+       very rapidly as the string gets longer. (The * repeat can match  0,  1,
+       2,  3, or 4 times, and for each of those cases other than 0 or 4, the +
+       repeats can match different numbers of times.) When  the  remainder  of
+       the pattern is such that the entire match is going to fail, PCRE has in
+       principle to try  every  possible  variation,  and  this  can  take  an
+       extremely long time, even for relatively short strings.
+
+       An optimization catches some of the more simple cases such as
+
+         (a+)*b
+
+       where  a  literal  character  follows. Before embarking on the standard
+       matching procedure, PCRE checks that there is a "b" later in  the  sub-
+       ject  string, and if there is not, it fails the match immediately. How-
+       ever, when there is no following literal this  optimization  cannot  be
+       used. You can see the difference by comparing the behaviour of
+
+         (a+)*\d
+
+       with  the  pattern  above.  The former gives a failure almost instantly
+       when applied to a whole line of  "a"  characters,  whereas  the  latter
+       takes an appreciable time with strings longer than about 20 characters.
+
+       In many cases, the solution to this kind of performance issue is to use
+       an atomic group or a possessive quantifier.
+
+
+AUTHOR
+
+       Philip Hazel
+       University Computing Service
+       Cambridge CB2 3QH, England.
+
+
+REVISION
+
+       Last updated: 25 August 2012
+       Copyright (c) 1997-2012 University of Cambridge.
+------------------------------------------------------------------------------
+
+
+PCREPOSIX(3)               Library Functions Manual               PCREPOSIX(3)
+
+
+
+NAME
+       PCRE - Perl-compatible regular expressions.
+
+SYNOPSIS
+
+       #include <pcreposix.h>
+
+       int regcomp(regex_t *preg, const char *pattern,
+            int cflags);
+
+       int regexec(regex_t *preg, const char *string,
+            size_t nmatch, regmatch_t pmatch[], int eflags);
+            size_t regerror(int errcode, const regex_t *preg,
+            char *errbuf, size_t errbuf_size);
+
+       void regfree(regex_t *preg);
+
+
+DESCRIPTION
+
+       This  set  of functions provides a POSIX-style API for the PCRE regular
+       expression 8-bit library. See the pcreapi documentation for a  descrip-
+       tion  of  PCRE's native API, which contains much additional functional-
+       ity. There is no POSIX-style  wrapper  for  PCRE's  16-bit  and  32-bit
+       library.
+
+       The functions described here are just wrapper functions that ultimately
+       call  the  PCRE  native  API.  Their  prototypes  are  defined  in  the
+       pcreposix.h  header  file,  and  on  Unix systems the library itself is
+       called pcreposix.a, so can be accessed by  adding  -lpcreposix  to  the
+       command  for  linking  an application that uses them. Because the POSIX
+       functions call the native ones, it is also necessary to add -lpcre.
+
+       I have implemented only those POSIX option bits that can be  reasonably
+       mapped  to PCRE native options. In addition, the option REG_EXTENDED is
+       defined with the value zero. This has no  effect,  but  since  programs
+       that  are  written  to  the POSIX interface often use it, this makes it
+       easier to slot in PCRE as a replacement library.  Other  POSIX  options
+       are not even defined.
+
+       There  are also some other options that are not defined by POSIX. These
+       have been added at the request of users who want to make use of certain
+       PCRE-specific features via the POSIX calling interface.
+
+       When  PCRE  is  called  via these functions, it is only the API that is
+       POSIX-like in style. The syntax and semantics of  the  regular  expres-
+       sions  themselves  are  still  those of Perl, subject to the setting of
+       various PCRE options, as described below. "POSIX-like in  style"  means
+       that  the  API  approximates  to  the POSIX definition; it is not fully
+       POSIX-compatible, and in multi-byte encoding  domains  it  is  probably
+       even less compatible.
+
+       The  header for these functions is supplied as pcreposix.h to avoid any
+       potential clash with other POSIX  libraries.  It  can,  of  course,  be
+       renamed or aliased as regex.h, which is the "correct" name. It provides
+       two structure types, regex_t for  compiled  internal  forms,  and  reg-
+       match_t  for  returning  captured substrings. It also defines some con-
+       stants whose names start  with  "REG_";  these  are  used  for  setting
+       options and identifying error codes.
+
+
+COMPILING A PATTERN
+
+       The  function regcomp() is called to compile a pattern into an internal
+       form. The pattern is a C string terminated by a  binary  zero,  and  is
+       passed  in  the  argument  pattern. The preg argument is a pointer to a
+       regex_t structure that is used as a base for storing information  about
+       the compiled regular expression.
+
+       The argument cflags is either zero, or contains one or more of the bits
+       defined by the following macros:
+
+         REG_DOTALL
+
+       The PCRE_DOTALL option is set when the regular expression is passed for
+       compilation to the native function. Note that REG_DOTALL is not part of
+       the POSIX standard.
+
+         REG_ICASE
+
+       The PCRE_CASELESS option is set when the regular expression  is  passed
+       for compilation to the native function.
+
+         REG_NEWLINE
+
+       The  PCRE_MULTILINE option is set when the regular expression is passed
+       for compilation to the native function. Note that this does  not  mimic
+       the  defined  POSIX  behaviour  for REG_NEWLINE (see the following sec-
+       tion).
+
+         REG_NOSUB
+
+       The PCRE_NO_AUTO_CAPTURE option is set when the regular  expression  is
+       passed for compilation to the native function. In addition, when a pat-
+       tern that is compiled with this flag is passed to regexec() for  match-
+       ing,  the  nmatch  and  pmatch  arguments  are ignored, and no captured
+       strings are returned.
+
+         REG_UCP
+
+       The PCRE_UCP option is set when the regular expression  is  passed  for
+       compilation  to  the  native  function. This causes PCRE to use Unicode
+       properties when matchine \d, \w,  etc.,  instead  of  just  recognizing
+       ASCII values. Note that REG_UTF8 is not part of the POSIX standard.
+
+         REG_UNGREEDY
+
+       The  PCRE_UNGREEDY  option is set when the regular expression is passed
+       for compilation to the native function. Note that REG_UNGREEDY  is  not
+       part of the POSIX standard.
+
+         REG_UTF8
+
+       The  PCRE_UTF8  option is set when the regular expression is passed for
+       compilation to the native function. This causes the pattern itself  and
+       all  data  strings used for matching it to be treated as UTF-8 strings.
+       Note that REG_UTF8 is not part of the POSIX standard.
+
+       In the absence of these flags, no options  are  passed  to  the  native
+       function.   This  means  the  the  regex  is compiled with PCRE default
+       semantics. In particular, the way it handles newline characters in  the
+       subject  string  is  the Perl way, not the POSIX way. Note that setting
+       PCRE_MULTILINE has only some of the effects specified for  REG_NEWLINE.
+       It  does not affect the way newlines are matched by . (they are not) or
+       by a negative class such as [^a] (they are).
+
+       The yield of regcomp() is zero on success, and non-zero otherwise.  The
+       preg structure is filled in on success, and one member of the structure
+       is public: re_nsub contains the number of capturing subpatterns in  the
+       regular expression. Various error codes are defined in the header file.
+
+       NOTE:  If  the  yield of regcomp() is non-zero, you must not attempt to
+       use the contents of the preg structure. If, for example, you pass it to
+       regexec(), the result is undefined and your program is likely to crash.
+
+
+MATCHING NEWLINE CHARACTERS
+
+       This area is not simple, because POSIX and Perl take different views of
+       things.  It is not possible to get PCRE to obey  POSIX  semantics,  but
+       then  PCRE was never intended to be a POSIX engine. The following table
+       lists the different possibilities for matching  newline  characters  in
+       PCRE:
+
+                                 Default   Change with
+
+         . matches newline          no     PCRE_DOTALL
+         newline matches [^a]       yes    not changeable
+         $ matches \n at end        yes    PCRE_DOLLARENDONLY
+         $ matches \n in middle     no     PCRE_MULTILINE
+         ^ matches \n in middle     no     PCRE_MULTILINE
+
+       This is the equivalent table for POSIX:
+
+                                 Default   Change with
+
+         . matches newline          yes    REG_NEWLINE
+         newline matches [^a]       yes    REG_NEWLINE
+         $ matches \n at end        no     REG_NEWLINE
+         $ matches \n in middle     no     REG_NEWLINE
+         ^ matches \n in middle     no     REG_NEWLINE
+
+       PCRE's behaviour is the same as Perl's, except that there is no equiva-
+       lent for PCRE_DOLLAR_ENDONLY in Perl. In both PCRE and Perl,  there  is
+       no way to stop newline from matching [^a].
+
+       The   default  POSIX  newline  handling  can  be  obtained  by  setting
+       PCRE_DOTALL and PCRE_DOLLAR_ENDONLY, but there is no way to  make  PCRE
+       behave exactly as for the REG_NEWLINE action.
+
+
+MATCHING A PATTERN
+
+       The  function  regexec()  is  called  to  match a compiled pattern preg
+       against a given string, which is by default terminated by a  zero  byte
+       (but  see  REG_STARTEND below), subject to the options in eflags. These
+       can be:
+
+         REG_NOTBOL
+
+       The PCRE_NOTBOL option is set when calling the underlying PCRE matching
+       function.
+
+         REG_NOTEMPTY
+
+       The PCRE_NOTEMPTY option is set when calling the underlying PCRE match-
+       ing function. Note that REG_NOTEMPTY is not part of the POSIX standard.
+       However, setting this option can give more POSIX-like behaviour in some
+       situations.
+
+         REG_NOTEOL
+
+       The PCRE_NOTEOL option is set when calling the underlying PCRE matching
+       function.
+
+         REG_STARTEND
+
+       The  string  is  considered to start at string + pmatch[0].rm_so and to
+       have a terminating NUL located at string + pmatch[0].rm_eo (there  need
+       not  actually  be  a  NUL at that location), regardless of the value of
+       nmatch. This is a BSD extension, compatible with but not  specified  by
+       IEEE  Standard  1003.2  (POSIX.2),  and  should be used with caution in
+       software intended to be portable to other systems. Note that a non-zero
+       rm_so does not imply REG_NOTBOL; REG_STARTEND affects only the location
+       of the string, not how it is matched.
+
+       If the pattern was compiled with the REG_NOSUB flag, no data about  any
+       matched  strings  is  returned.  The  nmatch  and  pmatch  arguments of
+       regexec() are ignored.
+
+       If the value of nmatch is zero, or if the value pmatch is NULL, no data
+       about any matched strings is returned.
+
+       Otherwise,the portion of the string that was matched, and also any cap-
+       tured substrings, are returned via the pmatch argument, which points to
+       an  array  of nmatch structures of type regmatch_t, containing the mem-
+       bers rm_so and rm_eo. These contain the offset to the  first  character
+       of  each  substring and the offset to the first character after the end
+       of each substring, respectively. The 0th element of the vector  relates
+       to  the  entire portion of string that was matched; subsequent elements
+       relate to the capturing subpatterns of the regular  expression.  Unused
+       entries in the array have both structure members set to -1.
+
+       A  successful  match  yields  a  zero  return;  various error codes are
+       defined in the header file, of  which  REG_NOMATCH  is  the  "expected"
+       failure code.
+
+
+ERROR MESSAGES
+
+       The regerror() function maps a non-zero errorcode from either regcomp()
+       or regexec() to a printable message. If preg is  not  NULL,  the  error
+       should have arisen from the use of that structure. A message terminated
+       by a binary zero is placed  in  errbuf.  The  length  of  the  message,
+       including  the  zero, is limited to errbuf_size. The yield of the func-
+       tion is the size of buffer needed to hold the whole message.
+
+
+MEMORY USAGE
+
+       Compiling a regular expression causes memory to be allocated and  asso-
+       ciated  with  the preg structure. The function regfree() frees all such
+       memory, after which preg may no longer be used as  a  compiled  expres-
+       sion.
+
+
+AUTHOR
+
+       Philip Hazel
+       University Computing Service
+       Cambridge CB2 3QH, England.
+
+
+REVISION
+
+       Last updated: 09 January 2012
+       Copyright (c) 1997-2012 University of Cambridge.
+------------------------------------------------------------------------------
+
+
+PCRECPP(3)                 Library Functions Manual                 PCRECPP(3)
+
+
+
+NAME
+       PCRE - Perl-compatible regular expressions.
+
+SYNOPSIS OF C++ WRAPPER
+
+       #include <pcrecpp.h>
+
+
+DESCRIPTION
+
+       The  C++  wrapper  for PCRE was provided by Google Inc. Some additional
+       functionality was added by Giuseppe Maxia. This brief man page was con-
+       structed  from  the  notes  in the pcrecpp.h file, which should be con-
+       sulted for further details. Note that the C++ wrapper supports only the
+       original  8-bit  PCRE  library. There is no 16-bit or 32-bit support at
+       present.
+
+
+MATCHING INTERFACE
+
+       The "FullMatch" operation checks that supplied text matches a  supplied
+       pattern  exactly.  If pointer arguments are supplied, it copies matched
+       sub-strings that match sub-patterns into them.
+
+         Example: successful match
+            pcrecpp::RE re("h.*o");
+            re.FullMatch("hello");
+
+         Example: unsuccessful match (requires full match):
+            pcrecpp::RE re("e");
+            !re.FullMatch("hello");
+
+         Example: creating a temporary RE object:
+            pcrecpp::RE("h.*o").FullMatch("hello");
+
+       You can pass in a "const char*" or a "string" for "text". The  examples
+       below  tend to use a const char*. You can, as in the different examples
+       above, store the RE object explicitly in a variable or use a  temporary
+       RE  object.  The  examples below use one mode or the other arbitrarily.
+       Either could correctly be used for any of these examples.
+
+       You must supply extra pointer arguments to extract matched subpieces.
+
+         Example: extracts "ruby" into "s" and 1234 into "i"
+            int i;
+            string s;
+            pcrecpp::RE re("(\\w+):(\\d+)");
+            re.FullMatch("ruby:1234", &s, &i);
+
+         Example: does not try to extract any extra sub-patterns
+            re.FullMatch("ruby:1234", &s);
+
+         Example: does not try to extract into NULL
+            re.FullMatch("ruby:1234", NULL, &i);
+
+         Example: integer overflow causes failure
+            !re.FullMatch("ruby:1234567891234", NULL, &i);
+
+         Example: fails because there aren't enough sub-patterns:
+            !pcrecpp::RE("\\w+:\\d+").FullMatch("ruby:1234", &s);
+
+         Example: fails because string cannot be stored in integer
+            !pcrecpp::RE("(.*)").FullMatch("ruby", &i);
+
+       The provided pointer arguments can be pointers to  any  scalar  numeric
+       type, or one of:
+
+          string        (matched piece is copied to string)
+          StringPiece   (StringPiece is mutated to point to matched piece)
+          T             (where "bool T::ParseFrom(const char*, int)" exists)
+          NULL          (the corresponding matched sub-pattern is not copied)
+
+       The  function returns true iff all of the following conditions are sat-
+       isfied:
+
+         a. "text" matches "pattern" exactly;
+
+         b. The number of matched sub-patterns is >= number of supplied
+            pointers;
+
+         c. The "i"th argument has a suitable type for holding the
+            string captured as the "i"th sub-pattern. If you pass in
+            void * NULL for the "i"th argument, or a non-void * NULL
+            of the correct type, or pass fewer arguments than the
+            number of sub-patterns, "i"th captured sub-pattern is
+            ignored.
+
+       CAVEAT: An optional sub-pattern that does  not  exist  in  the  matched
+       string  is  assigned  the  empty  string. Therefore, the following will
+       return false (because the empty string is not a valid number):
+
+          int number;
+          pcrecpp::RE::FullMatch("abc", "[a-z]+(\\d+)?", &number);
+
+       The matching interface supports at most 16 arguments per call.  If  you
+       need    more,    consider    using    the    more   general   interface
+       pcrecpp::RE::DoMatch. See pcrecpp.h for the signature for DoMatch.
+
+       NOTE: Do not use no_arg, which is used internally to mark the end of  a
+       list  of optional arguments, as a placeholder for missing arguments, as
+       this can lead to segfaults.
+
+
+QUOTING METACHARACTERS
+
+       You can use the "QuoteMeta" operation to insert backslashes before  all
+       potentially  meaningful  characters  in  a string. The returned string,
+       used as a regular expression, will exactly match the original string.
+
+         Example:
+            string quoted = RE::QuoteMeta(unquoted);
+
+       Note that it's legal to escape a character even if it  has  no  special
+       meaning  in  a  regular expression -- so this function does that. (This
+       also makes it identical to the perl function  of  the  same  name;  see
+       "perldoc    -f    quotemeta".)    For   example,   "1.5-2.0?"   becomes
+       "1\.5\-2\.0\?".
+
+
+PARTIAL MATCHES
+
+       You can use the "PartialMatch" operation when you want the  pattern  to
+       match any substring of the text.
+
+         Example: simple search for a string:
+            pcrecpp::RE("ell").PartialMatch("hello");
+
+         Example: find first number in a string:
+            int number;
+            pcrecpp::RE re("(\\d+)");
+            re.PartialMatch("x*100 + 20", &number);
+            assert(number == 100);
+
+
+UTF-8 AND THE MATCHING INTERFACE
+
+       By  default,  pattern  and text are plain text, one byte per character.
+       The UTF8 flag, passed to  the  constructor,  causes  both  pattern  and
+       string to be treated as UTF-8 text, still a byte stream but potentially
+       multiple bytes per character. In practice, the text is likelier  to  be
+       UTF-8  than  the pattern, but the match returned may depend on the UTF8
+       flag, so always use it when matching UTF8 text. For example,  "."  will
+       match  one  byte normally but with UTF8 set may match up to three bytes
+       of a multi-byte character.
+
+         Example:
+            pcrecpp::RE_Options options;
+            options.set_utf8();
+            pcrecpp::RE re(utf8_pattern, options);
+            re.FullMatch(utf8_string);
+
+         Example: using the convenience function UTF8():
+            pcrecpp::RE re(utf8_pattern, pcrecpp::UTF8());
+            re.FullMatch(utf8_string);
+
+       NOTE: The UTF8 flag is ignored if pcre was not configured with the
+             --enable-utf8 flag.
+
+
+PASSING MODIFIERS TO THE REGULAR EXPRESSION ENGINE
+
+       PCRE defines some modifiers to  change  the  behavior  of  the  regular
+       expression   engine.  The  C++  wrapper  defines  an  auxiliary  class,
+       RE_Options, as a vehicle to pass such modifiers to  a  RE  class.  Cur-
+       rently, the following modifiers are supported:
+
+          modifier              description               Perl corresponding
+
+          PCRE_CASELESS         case insensitive match      /i
+          PCRE_MULTILINE        multiple lines match        /m
+          PCRE_DOTALL           dot matches newlines        /s
+          PCRE_DOLLAR_ENDONLY   $ matches only at end       N/A
+          PCRE_EXTRA            strict escape parsing       N/A
+          PCRE_EXTENDED         ignore white spaces         /x
+          PCRE_UTF8             handles UTF8 chars          built-in
+          PCRE_UNGREEDY         reverses * and *?           N/A
+          PCRE_NO_AUTO_CAPTURE  disables capturing parens   N/A (*)
+
+       (*)  Both Perl and PCRE allow non capturing parentheses by means of the
+       "?:" modifier within the pattern itself. e.g. (?:ab|cd) does  not  cap-
+       ture, while (ab|cd) does.
+
+       For  a  full  account on how each modifier works, please check the PCRE
+       API reference page.
+
+       For each modifier, there are two member functions whose  name  is  made
+       out  of  the  modifier  in  lowercase,  without the "PCRE_" prefix. For
+       instance, PCRE_CASELESS is handled by
+
+         bool caseless()
+
+       which returns true if the modifier is set, and
+
+         RE_Options & set_caseless(bool)
+
+       which sets or unsets the modifier. Moreover, PCRE_EXTRA_MATCH_LIMIT can
+       be  accessed  through  the  set_match_limit()  and match_limit() member
+       functions. Setting match_limit to a non-zero value will limit the  exe-
+       cution  of pcre to keep it from doing bad things like blowing the stack
+       or taking an eternity to return a result.  A  value  of  5000  is  good
+       enough  to stop stack blowup in a 2MB thread stack. Setting match_limit
+       to  zero  disables  match  limiting.  Alternatively,   you   can   call
+       match_limit_recursion()  which uses PCRE_EXTRA_MATCH_LIMIT_RECURSION to
+       limit how much  PCRE  recurses.  match_limit()  limits  the  number  of
+       matches PCRE does; match_limit_recursion() limits the depth of internal
+       recursion, and therefore the amount of stack that is used.
+
+       Normally, to pass one or more modifiers to a RE class,  you  declare  a
+       RE_Options object, set the appropriate options, and pass this object to
+       a RE constructor. Example:
+
+          RE_Options opt;
+          opt.set_caseless(true);
+          if (RE("HELLO", opt).PartialMatch("hello world")) ...
+
+       RE_options has two constructors. The default constructor takes no argu-
+       ments  and creates a set of flags that are off by default. The optional
+       parameter option_flags is to facilitate transfer of legacy code from  C
+       programs.  This lets you do
+
+          RE(pattern,
+            RE_Options(PCRE_CASELESS|PCRE_MULTILINE)).PartialMatch(str);
+
+       However, new code is better off doing
+
+          RE(pattern,
+            RE_Options().set_caseless(true).set_multiline(true))
+              .PartialMatch(str);
+
+       If you are going to pass one of the most used modifiers, there are some
+       convenience functions that return a RE_Options class with the appropri-
+       ate  modifier  already  set: CASELESS(), UTF8(), MULTILINE(), DOTALL(),
+       and EXTENDED().
+
+       If you need to set several options at once, and you don't  want  to  go
+       through  the pains of declaring a RE_Options object and setting several
+       options, there is a parallel method that give you such ability  on  the
+       fly.  You  can  concatenate several set_xxxxx() member functions, since
+       each of them returns a reference to its class object. For  example,  to
+       pass  PCRE_CASELESS, PCRE_EXTENDED, and PCRE_MULTILINE to a RE with one
+       statement, you may write:
+
+          RE(" ^ xyz \\s+ .* blah$",
+            RE_Options()
+              .set_caseless(true)
+              .set_extended(true)
+              .set_multiline(true)).PartialMatch(sometext);
+
+
+SCANNING TEXT INCREMENTALLY
+
+       The "Consume" operation may be useful if you want to  repeatedly  match
+       regular expressions at the front of a string and skip over them as they
+       match. This requires use of the "StringPiece" type, which represents  a
+       sub-range  of  a  real  string.  Like RE, StringPiece is defined in the
+       pcrecpp namespace.
+
+         Example: read lines of the form "var = value" from a string.
+            string contents = ...;                 // Fill string somehow
+            pcrecpp::StringPiece input(contents);  // Wrap in a StringPiece
+
+            string var;
+            int value;
+            pcrecpp::RE re("(\\w+) = (\\d+)\n");
+            while (re.Consume(&input, &var, &value)) {
+              ...;
+            }
+
+       Each successful call  to  "Consume"  will  set  "var/value",  and  also
+       advance "input" so it points past the matched text.
+
+       The  "FindAndConsume"  operation  is  similar to "Consume" but does not
+       anchor your match at the beginning of  the  string.  For  example,  you
+       could extract all words from a string by repeatedly calling
+
+         pcrecpp::RE("(\\w+)").FindAndConsume(&input, &word)
+
+
+PARSING HEX/OCTAL/C-RADIX NUMBERS
+
+       By default, if you pass a pointer to a numeric value, the corresponding
+       text is interpreted as a base-10  number.  You  can  instead  wrap  the
+       pointer with a call to one of the operators Hex(), Octal(), or CRadix()
+       to interpret the text in another base. The CRadix  operator  interprets
+       C-style  "0"  (base-8)  and  "0x"  (base-16)  prefixes, but defaults to
+       base-10.
+
+         Example:
+           int a, b, c, d;
+           pcrecpp::RE re("(.*) (.*) (.*) (.*)");
+           re.FullMatch("100 40 0100 0x40",
+                        pcrecpp::Octal(&a), pcrecpp::Hex(&b),
+                        pcrecpp::CRadix(&c), pcrecpp::CRadix(&d));
+
+       will leave 64 in a, b, c, and d.
+
+
+REPLACING PARTS OF STRINGS
+
+       You can replace the first match of "pattern" in "str"  with  "rewrite".
+       Within  "rewrite",  backslash-escaped  digits (\1 to \9) can be used to
+       insert text matching corresponding parenthesized group  from  the  pat-
+       tern. \0 in "rewrite" refers to the entire matching text. For example:
+
+         string s = "yabba dabba doo";
+         pcrecpp::RE("b+").Replace("d", &s);
+
+       will  leave  "s" containing "yada dabba doo". The result is true if the
+       pattern matches and a replacement occurs, false otherwise.
+
+       GlobalReplace is like Replace except that it replaces  all  occurrences
+       of  the  pattern  in  the string with the rewrite. Replacements are not
+       subject to re-matching. For example:
+
+         string s = "yabba dabba doo";
+         pcrecpp::RE("b+").GlobalReplace("d", &s);
+
+       will leave "s" containing "yada dada doo". It  returns  the  number  of
+       replacements made.
+
+       Extract  is like Replace, except that if the pattern matches, "rewrite"
+       is copied into "out" (an additional argument) with substitutions.   The
+       non-matching  portions  of "text" are ignored. Returns true iff a match
+       occurred and the extraction happened successfully;  if no match occurs,
+       the string is left unaffected.
+
+
+AUTHOR
+
+       The C++ wrapper was contributed by Google Inc.
+       Copyright (c) 2007 Google Inc.
+
+
+REVISION
+
+       Last updated: 08 January 2012
+------------------------------------------------------------------------------
+
+
+PCRESAMPLE(3)              Library Functions Manual              PCRESAMPLE(3)
+
+
+
+NAME
+       PCRE - Perl-compatible regular expressions
+
+PCRE SAMPLE PROGRAM
+
+       A simple, complete demonstration program, to get you started with using
+       PCRE, is supplied in the file pcredemo.c in the  PCRE  distribution.  A
+       listing  of this program is given in the pcredemo documentation. If you
+       do not have a copy of the PCRE distribution, you can save this  listing
+       to re-create pcredemo.c.
+
+       The  demonstration program, which uses the original PCRE 8-bit library,
+       compiles the regular expression that is its first argument, and matches
+       it  against  the subject string in its second argument. No PCRE options
+       are set, and default character tables are used. If  matching  succeeds,
+       the  program  outputs the portion of the subject that matched, together
+       with the contents of any captured substrings.
+
+       If the -g option is given on the command line, the program then goes on
+       to check for further matches of the same regular expression in the same
+       subject string. The logic is a little bit tricky because of the  possi-
+       bility  of  matching an empty string. Comments in the code explain what
+       is going on.
+
+       If PCRE is installed in the standard include  and  library  directories
+       for your operating system, you should be able to compile the demonstra-
+       tion program using this command:
+
+         gcc -o pcredemo pcredemo.c -lpcre
+
+       If PCRE is installed elsewhere, you may need to add additional  options
+       to  the  command line. For example, on a Unix-like system that has PCRE
+       installed in /usr/local, you  can  compile  the  demonstration  program
+       using a command like this:
+
+         gcc -o pcredemo -I/usr/local/include pcredemo.c \
+             -L/usr/local/lib -lpcre
+
+       In  a  Windows  environment, if you want to statically link the program
+       against a non-dll pcre.a file, you must uncomment the line that defines
+       PCRE_STATIC  before  including  pcre.h, because otherwise the pcre_mal-
+       loc()   and   pcre_free()   exported   functions   will   be   declared
+       __declspec(dllimport), with unwanted results.
+
+       Once  you  have  compiled and linked the demonstration program, you can
+       run simple tests like this:
+
+         ./pcredemo 'cat|dog' 'the cat sat on the mat'
+         ./pcredemo -g 'cat|dog' 'the dog sat on the cat'
+
+       Note that there is a  much  more  comprehensive  test  program,  called
+       pcretest,  which  supports  many  more  facilities  for testing regular
+       expressions and both PCRE libraries. The pcredemo program  is  provided
+       as a simple coding example.
+
+       If  you  try to run pcredemo when PCRE is not installed in the standard
+       library directory, you may get an error like  this  on  some  operating
+       systems (e.g. Solaris):
+
+         ld.so.1:  a.out:  fatal:  libpcre.so.0:  open failed: No such file or
+       directory
+
+       This is caused by the way shared library support works  on  those  sys-
+       tems. You need to add
+
+         -R/usr/local/lib
+
+       (for example) to the compile command to get round this problem.
+
+
+AUTHOR
+
+       Philip Hazel
+       University Computing Service
+       Cambridge CB2 3QH, England.
+
+
+REVISION
+
+       Last updated: 10 January 2012
+       Copyright (c) 1997-2012 University of Cambridge.
+------------------------------------------------------------------------------
+PCRELIMITS(3)              Library Functions Manual              PCRELIMITS(3)
+
+
+
+NAME
+       PCRE - Perl-compatible regular expressions
+
+SIZE AND OTHER LIMITATIONS
+
+       There  are some size limitations in PCRE but it is hoped that they will
+       never in practice be relevant.
+
+       The maximum length of a compiled  pattern  is  approximately  64K  data
+       units  (bytes  for  the  8-bit  library,  16-bit  units  for the 16-bit
+       library, and 32-bit units for the 32-bit library) if PCRE  is  compiled
+       with  the default internal linkage size, which is 2 bytes for the 8-bit
+       and 16-bit libraries, and 4 bytes for the 32-bit library. If  you  want
+       to process regular expressions that are truly enormous, you can compile
+       PCRE with an internal linkage size of 3 or 4 (when building the  16-bit
+       or  32-bit  library,  3 is rounded up to 4). See the README file in the
+       source distribution and the pcrebuild  documentation  for  details.  In
+       these  cases  the limit is substantially larger.  However, the speed of
+       execution is slower.
+
+       All values in repeating quantifiers must be less than 65536.
+
+       There is no limit to the number of parenthesized subpatterns, but there
+       can  be  no more than 65535 capturing subpatterns. There is, however, a
+       limit to the depth of  nesting  of  parenthesized  subpatterns  of  all
+       kinds.  This  is  imposed  in order to limit the amount of system stack
+       used at compile time. The limit can be specified when  PCRE  is  built;
+       the default is 250.
+
+       There is a limit to the number of forward references to subsequent sub-
+       patterns of around 200,000.  Repeated  forward  references  with  fixed
+       upper  limits,  for example, (?2){0,100} when subpattern number 2 is to
+       the right, are included in the count. There is no limit to  the  number
+       of backward references.
+
+       The maximum length of name for a named subpattern is 32 characters, and
+       the maximum number of named subpatterns is 10000.
+
+       The maximum length of a  name  in  a  (*MARK),  (*PRUNE),  (*SKIP),  or
+       (*THEN)  verb is 255 for the 8-bit library and 65535 for the 16-bit and
+       32-bit libraries.
+
+       The maximum length of a subject string is the largest  positive  number
+       that  an integer variable can hold. However, when using the traditional
+       matching function, PCRE uses recursion to handle subpatterns and indef-
+       inite  repetition.  This means that the available stack space may limit
+       the size of a subject string that can be processed by certain patterns.
+       For a discussion of stack issues, see the pcrestack documentation.
+
+
+AUTHOR
+
+       Philip Hazel
+       University Computing Service
+       Cambridge CB2 3QH, England.
+
+
+REVISION
+
+       Last updated: 05 November 2013
+       Copyright (c) 1997-2013 University of Cambridge.
+------------------------------------------------------------------------------
+
+
+PCRESTACK(3)               Library Functions Manual               PCRESTACK(3)
+
+
+
+NAME
+       PCRE - Perl-compatible regular expressions
+
+PCRE DISCUSSION OF STACK USAGE
+
+       When  you call pcre[16|32]_exec(), it makes use of an internal function
+       called match(). This calls itself recursively at branch points  in  the
+       pattern,  in  order  to  remember the state of the match so that it can
+       back up and try a different alternative if  the  first  one  fails.  As
+       matching proceeds deeper and deeper into the tree of possibilities, the
+       recursion depth increases. The match() function is also called in other
+       circumstances,  for  example,  whenever  a parenthesized sub-pattern is
+       entered, and in certain cases of repetition.
+
+       Not all calls of match() increase the recursion depth; for an item such
+       as  a* it may be called several times at the same level, after matching
+       different numbers of a's. Furthermore, in a number of cases  where  the
+       result  of  the  recursive call would immediately be passed back as the
+       result of the current call (a "tail recursion"), the function  is  just
+       restarted instead.
+
+       The  above  comments apply when pcre[16|32]_exec() is run in its normal
+       interpretive  manner.   If   the   pattern   was   studied   with   the
+       PCRE_STUDY_JIT_COMPILE  option, and just-in-time compiling was success-
+       ful, and the options passed to pcre[16|32]_exec() were  not  incompati-
+       ble,  the  matching  process  uses the JIT-compiled code instead of the
+       match() function. In this case, the  memory  requirements  are  handled
+       entirely differently. See the pcrejit documentation for details.
+
+       The  pcre[16|32]_dfa_exec()  function operates in an entirely different
+       way, and uses recursion only when there is a regular expression  recur-
+       sion or subroutine call in the pattern. This includes the processing of
+       assertion and "once-only" subpatterns, which are handled  like  subrou-
+       tine  calls.  Normally, these are never very deep, and the limit on the
+       complexity of pcre[16|32]_dfa_exec() is controlled  by  the  amount  of
+       workspace  it is given.  However, it is possible to write patterns with
+       runaway    infinite    recursions;    such    patterns    will    cause
+       pcre[16|32]_dfa_exec()  to  run  out  of stack. At present, there is no
+       protection against this.
+
+       The comments that follow do NOT apply to  pcre[16|32]_dfa_exec();  they
+       are relevant only for pcre[16|32]_exec() without the JIT optimization.
+
+   Reducing pcre[16|32]_exec()'s stack usage
+
+       Each  time  that match() is actually called recursively, it uses memory
+       from the process stack. For certain kinds of  pattern  and  data,  very
+       large  amounts of stack may be needed, despite the recognition of "tail
+       recursion".  You can often reduce the amount of recursion,  and  there-
+       fore  the  amount of stack used, by modifying the pattern that is being
+       matched. Consider, for example, this pattern:
+
+         ([^<]|<(?!inet))+
+
+       It matches from wherever it starts until it encounters "<inet"  or  the
+       end  of  the  data,  and is the kind of pattern that might be used when
+       processing an XML file. Each iteration of the outer parentheses matches
+       either  one  character that is not "<" or a "<" that is not followed by
+       "inet". However, each time a  parenthesis  is  processed,  a  recursion
+       occurs, so this formulation uses a stack frame for each matched charac-
+       ter. For a long string, a lot of stack is required. Consider  now  this
+       rewritten pattern, which matches exactly the same strings:
+
+         ([^<]++|<(?!inet))+
+
+       This  uses very much less stack, because runs of characters that do not
+       contain "<" are "swallowed" in one item inside the parentheses.  Recur-
+       sion  happens  only when a "<" character that is not followed by "inet"
+       is encountered (and we assume this is relatively  rare).  A  possessive
+       quantifier  is  used  to stop any backtracking into the runs of non-"<"
+       characters, but that is not related to stack usage.
+
+       This example shows that one way of avoiding stack problems when  match-
+       ing long subject strings is to write repeated parenthesized subpatterns
+       to match more than one character whenever possible.
+
+   Compiling PCRE to use heap instead of stack for pcre[16|32]_exec()
+
+       In environments where stack memory is constrained, you  might  want  to
+       compile  PCRE to use heap memory instead of stack for remembering back-
+       up points when pcre[16|32]_exec() is running. This makes it run  a  lot
+       more slowly, however.  Details of how to do this are given in the pcre-
+       build documentation. When built in  this  way,  instead  of  using  the
+       stack,  PCRE obtains and frees memory by calling the functions that are
+       pointed to by the pcre[16|32]_stack_malloc  and  pcre[16|32]_stack_free
+       variables.  By default, these point to malloc() and free(), but you can
+       replace the pointers to cause PCRE to use your own functions. Since the
+       block sizes are always the same, and are always freed in reverse order,
+       it may be possible to implement customized  memory  handlers  that  are
+       more efficient than the standard functions.
+
+   Limiting pcre[16|32]_exec()'s stack usage
+
+       You  can set limits on the number of times that match() is called, both
+       in total and recursively. If a limit  is  exceeded,  pcre[16|32]_exec()
+       returns  an  error code. Setting suitable limits should prevent it from
+       running out of stack. The default values of the limits are very  large,
+       and  unlikely  ever to operate. They can be changed when PCRE is built,
+       and they can also be set when pcre[16|32]_exec() is called. For details
+       of these interfaces, see the pcrebuild documentation and the section on
+       extra data for pcre[16|32]_exec() in the pcreapi documentation.
+
+       As a very rough rule of thumb, you should reckon on about 500 bytes per
+       recursion.  Thus,  if  you  want  to limit your stack usage to 8Mb, you
+       should set the limit at 16000 recursions. A 64Mb stack,  on  the  other
+       hand, can support around 128000 recursions.
+
+       In Unix-like environments, the pcretest test program has a command line
+       option (-S) that can be used to increase the size of its stack. As long
+       as  the  stack is large enough, another option (-M) can be used to find
+       the smallest limits that allow a particular pattern to  match  a  given
+       subject  string.  This is done by calling pcre[16|32]_exec() repeatedly
+       with different limits.
+
+   Obtaining an estimate of stack usage
+
+       The actual amount of stack used per recursion can  vary  quite  a  lot,
+       depending on the compiler that was used to build PCRE and the optimiza-
+       tion or debugging options that were set for it. The rule of thumb value
+       of  500  bytes  mentioned  above  may be larger or smaller than what is
+       actually needed. A better approximation can be obtained by running this
+       command:
+
+         pcretest -m -C
+
+       The  -C  option causes pcretest to output information about the options
+       with which PCRE was compiled. When -m is also given (before -C), infor-
+       mation about stack use is given in a line like this:
+
+         Match recursion uses stack: approximate frame size = 640 bytes
+
+       The value is approximate because some recursions need a bit more (up to
+       perhaps 16 more bytes).
+
+       If the above command is given when PCRE is compiled  to  use  the  heap
+       instead  of  the  stack  for recursion, the value that is output is the
+       size of each block that is obtained from the heap.
+
+   Changing stack size in Unix-like systems
+
+       In Unix-like environments, there is not often a problem with the  stack
+       unless  very  long  strings  are  involved, though the default limit on
+       stack size varies from system to system. Values from 8Mb  to  64Mb  are
+       common. You can find your default limit by running the command:
+
+         ulimit -s
+
+       Unfortunately,  the  effect  of  running out of stack is often SIGSEGV,
+       though sometimes a more explicit error message is given. You  can  nor-
+       mally increase the limit on stack size by code such as this:
+
+         struct rlimit rlim;
+         getrlimit(RLIMIT_STACK, &rlim);
+         rlim.rlim_cur = 100*1024*1024;
+         setrlimit(RLIMIT_STACK, &rlim);
+
+       This  reads  the current limits (soft and hard) using getrlimit(), then
+       attempts to increase the soft limit to  100Mb  using  setrlimit().  You
+       must do this before calling pcre[16|32]_exec().
+
+   Changing stack size in Mac OS X
+
+       Using setrlimit(), as described above, should also work on Mac OS X. It
+       is also possible to set a stack size when linking a program. There is a
+       discussion   about   stack  sizes  in  Mac  OS  X  at  this  web  site:
+       http://developer.apple.com/qa/qa2005/qa1419.html.
+
+
+AUTHOR
+
+       Philip Hazel
+       University Computing Service
+       Cambridge CB2 3QH, England.
+
+
+REVISION
+
+       Last updated: 24 June 2012
+       Copyright (c) 1997-2012 University of Cambridge.
+------------------------------------------------------------------------------
+
+
diff --git a/libs/Pcre16/docs/doc/pcre16.3 b/libs/Pcre16/docs/doc/pcre16.3
new file mode 100644
index 0000000000..85126a6792
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcre16.3
@@ -0,0 +1,371 @@
+.TH PCRE 3 "12 May 2013" "PCRE 8.33"
+.SH NAME
+PCRE - Perl-compatible regular expressions
+.sp
+.B #include <pcre.h>
+.
+.
+.SH "PCRE 16-BIT API BASIC FUNCTIONS"
+.rs
+.sp
+.nf
+.B pcre16 *pcre16_compile(PCRE_SPTR16 \fIpattern\fP, int \fIoptions\fP,
+.B "     const char **\fIerrptr\fP, int *\fIerroffset\fP,"
+.B "     const unsigned char *\fItableptr\fP);"
+.sp
+.B pcre16 *pcre16_compile2(PCRE_SPTR16 \fIpattern\fP, int \fIoptions\fP,
+.B "     int *\fIerrorcodeptr\fP,"
+.B "     const char **\fIerrptr\fP, int *\fIerroffset\fP,"
+.B "     const unsigned char *\fItableptr\fP);"
+.sp
+.B pcre16_extra *pcre16_study(const pcre16 *\fIcode\fP, int \fIoptions\fP,
+.B "     const char **\fIerrptr\fP);"
+.sp
+.B void pcre16_free_study(pcre16_extra *\fIextra\fP);
+.sp
+.B int pcre16_exec(const pcre16 *\fIcode\fP, "const pcre16_extra *\fIextra\fP,"
+.B "     PCRE_SPTR16 \fIsubject\fP, int \fIlength\fP, int \fIstartoffset\fP,"
+.B "     int \fIoptions\fP, int *\fIovector\fP, int \fIovecsize\fP);"
+.sp
+.B int pcre16_dfa_exec(const pcre16 *\fIcode\fP, "const pcre16_extra *\fIextra\fP,"
+.B "     PCRE_SPTR16 \fIsubject\fP, int \fIlength\fP, int \fIstartoffset\fP,"
+.B "     int \fIoptions\fP, int *\fIovector\fP, int \fIovecsize\fP,"
+.B "     int *\fIworkspace\fP, int \fIwscount\fP);"
+.fi
+.
+.
+.SH "PCRE 16-BIT API STRING EXTRACTION FUNCTIONS"
+.rs
+.sp
+.nf
+.B int pcre16_copy_named_substring(const pcre16 *\fIcode\fP,
+.B "     PCRE_SPTR16 \fIsubject\fP, int *\fIovector\fP,"
+.B "     int \fIstringcount\fP, PCRE_SPTR16 \fIstringname\fP,"
+.B "     PCRE_UCHAR16 *\fIbuffer\fP, int \fIbuffersize\fP);"
+.sp
+.B int pcre16_copy_substring(PCRE_SPTR16 \fIsubject\fP, int *\fIovector\fP,
+.B "     int \fIstringcount\fP, int \fIstringnumber\fP, PCRE_UCHAR16 *\fIbuffer\fP,"
+.B "     int \fIbuffersize\fP);"
+.sp
+.B int pcre16_get_named_substring(const pcre16 *\fIcode\fP,
+.B "     PCRE_SPTR16 \fIsubject\fP, int *\fIovector\fP,"
+.B "     int \fIstringcount\fP, PCRE_SPTR16 \fIstringname\fP,"
+.B "     PCRE_SPTR16 *\fIstringptr\fP);"
+.sp
+.B int pcre16_get_stringnumber(const pcre16 *\fIcode\fP,
+.B "     PCRE_SPTR16 \fIname\fP);
+.sp
+.B int pcre16_get_stringtable_entries(const pcre16 *\fIcode\fP,
+.B "     PCRE_SPTR16 \fIname\fP, PCRE_UCHAR16 **\fIfirst\fP, PCRE_UCHAR16 **\fIlast\fP);"
+.sp
+.B int pcre16_get_substring(PCRE_SPTR16 \fIsubject\fP, int *\fIovector\fP,
+.B "     int \fIstringcount\fP, int \fIstringnumber\fP,"
+.B "     PCRE_SPTR16 *\fIstringptr\fP);"
+.sp
+.B int pcre16_get_substring_list(PCRE_SPTR16 \fIsubject\fP,
+.B "     int *\fIovector\fP, int \fIstringcount\fP, PCRE_SPTR16 **\fIlistptr\fP);"
+.sp
+.B void pcre16_free_substring(PCRE_SPTR16 \fIstringptr\fP);
+.sp
+.B void pcre16_free_substring_list(PCRE_SPTR16 *\fIstringptr\fP);
+.fi
+.
+.
+.SH "PCRE 16-BIT API AUXILIARY FUNCTIONS"
+.rs
+.sp
+.nf
+.B pcre16_jit_stack *pcre16_jit_stack_alloc(int \fIstartsize\fP, int \fImaxsize\fP);
+.sp
+.B void pcre16_jit_stack_free(pcre16_jit_stack *\fIstack\fP);
+.sp
+.B void pcre16_assign_jit_stack(pcre16_extra *\fIextra\fP,
+.B "     pcre16_jit_callback \fIcallback\fP, void *\fIdata\fP);"
+.sp
+.B const unsigned char *pcre16_maketables(void);
+.sp
+.B int pcre16_fullinfo(const pcre16 *\fIcode\fP, "const pcre16_extra *\fIextra\fP,"
+.B "     int \fIwhat\fP, void *\fIwhere\fP);"
+.sp
+.B int pcre16_refcount(pcre16 *\fIcode\fP, int \fIadjust\fP);
+.sp
+.B int pcre16_config(int \fIwhat\fP, void *\fIwhere\fP);
+.sp
+.B const char *pcre16_version(void);
+.sp
+.B int pcre16_pattern_to_host_byte_order(pcre16 *\fIcode\fP,
+.B "     pcre16_extra *\fIextra\fP, const unsigned char *\fItables\fP);"
+.fi
+.
+.
+.SH "PCRE 16-BIT API INDIRECTED FUNCTIONS"
+.rs
+.sp
+.nf
+.B void *(*pcre16_malloc)(size_t);
+.sp
+.B void (*pcre16_free)(void *);
+.sp
+.B void *(*pcre16_stack_malloc)(size_t);
+.sp
+.B void (*pcre16_stack_free)(void *);
+.sp
+.B int (*pcre16_callout)(pcre16_callout_block *);
+.fi
+.
+.
+.SH "PCRE 16-BIT API 16-BIT-ONLY FUNCTION"
+.rs
+.sp
+.nf
+.B int pcre16_utf16_to_host_byte_order(PCRE_UCHAR16 *\fIoutput\fP,
+.B "     PCRE_SPTR16 \fIinput\fP, int \fIlength\fP, int *\fIbyte_order\fP,"
+.B "     int \fIkeep_boms\fP);"
+.fi
+.
+.
+.SH "THE PCRE 16-BIT LIBRARY"
+.rs
+.sp
+Starting with release 8.30, it is possible to compile a PCRE library that
+supports 16-bit character strings, including UTF-16 strings, as well as or
+instead of the original 8-bit library. The majority of the work to make this
+possible was done by Zoltan Herczeg. The two libraries contain identical sets
+of functions, used in exactly the same way. Only the names of the functions and
+the data types of their arguments and results are different. To avoid
+over-complication and reduce the documentation maintenance load, most of the
+PCRE documentation describes the 8-bit library, with only occasional references
+to the 16-bit library. This page describes what is different when you use the
+16-bit library.
+.P
+WARNING: A single application can be linked with both libraries, but you must
+take care when processing any particular pattern to use functions from just one
+library. For example, if you want to study a pattern that was compiled with
+\fBpcre16_compile()\fP, you must do so with \fBpcre16_study()\fP, not
+\fBpcre_study()\fP, and you must free the study data with
+\fBpcre16_free_study()\fP.
+.
+.
+.SH "THE HEADER FILE"
+.rs
+.sp
+There is only one header file, \fBpcre.h\fP. It contains prototypes for all the
+functions in all libraries, as well as definitions of flags, structures, error
+codes, etc.
+.
+.
+.SH "THE LIBRARY NAME"
+.rs
+.sp
+In Unix-like systems, the 16-bit library is called \fBlibpcre16\fP, and can
+normally be accesss by adding \fB-lpcre16\fP to the command for linking an
+application that uses PCRE.
+.
+.
+.SH "STRING TYPES"
+.rs
+.sp
+In the 8-bit library, strings are passed to PCRE library functions as vectors
+of bytes with the C type "char *". In the 16-bit library, strings are passed as
+vectors of unsigned 16-bit quantities. The macro PCRE_UCHAR16 specifies an
+appropriate data type, and PCRE_SPTR16 is defined as "const PCRE_UCHAR16 *". In
+very many environments, "short int" is a 16-bit data type. When PCRE is built,
+it defines PCRE_UCHAR16 as "unsigned short int", but checks that it really is a
+16-bit data type. If it is not, the build fails with an error message telling
+the maintainer to modify the definition appropriately.
+.
+.
+.SH "STRUCTURE TYPES"
+.rs
+.sp
+The types of the opaque structures that are used for compiled 16-bit patterns
+and JIT stacks are \fBpcre16\fP and \fBpcre16_jit_stack\fP respectively. The
+type of the user-accessible structure that is returned by \fBpcre16_study()\fP
+is \fBpcre16_extra\fP, and the type of the structure that is used for passing
+data to a callout function is \fBpcre16_callout_block\fP. These structures
+contain the same fields, with the same names, as their 8-bit counterparts. The
+only difference is that pointers to character strings are 16-bit instead of
+8-bit types.
+.
+.
+.SH "16-BIT FUNCTIONS"
+.rs
+.sp
+For every function in the 8-bit library there is a corresponding function in
+the 16-bit library with a name that starts with \fBpcre16_\fP instead of
+\fBpcre_\fP. The prototypes are listed above. In addition, there is one extra
+function, \fBpcre16_utf16_to_host_byte_order()\fP. This is a utility function
+that converts a UTF-16 character string to host byte order if necessary. The
+other 16-bit functions expect the strings they are passed to be in host byte
+order.
+.P
+The \fIinput\fP and \fIoutput\fP arguments of
+\fBpcre16_utf16_to_host_byte_order()\fP may point to the same address, that is,
+conversion in place is supported. The output buffer must be at least as long as
+the input.
+.P
+The \fIlength\fP argument specifies the number of 16-bit data units in the
+input string; a negative value specifies a zero-terminated string.
+.P
+If \fIbyte_order\fP is NULL, it is assumed that the string starts off in host
+byte order. This may be changed by byte-order marks (BOMs) anywhere in the
+string (commonly as the first character).
+.P
+If \fIbyte_order\fP is not NULL, a non-zero value of the integer to which it
+points means that the input starts off in host byte order, otherwise the
+opposite order is assumed. Again, BOMs in the string can change this. The final
+byte order is passed back at the end of processing.
+.P
+If \fIkeep_boms\fP is not zero, byte-order mark characters (0xfeff) are copied
+into the output string. Otherwise they are discarded.
+.P
+The result of the function is the number of 16-bit units placed into the output
+buffer, including the zero terminator if the string was zero-terminated.
+.
+.
+.SH "SUBJECT STRING OFFSETS"
+.rs
+.sp
+The lengths and starting offsets of subject strings must be specified in 16-bit
+data units, and the offsets within subject strings that are returned by the
+matching functions are in also 16-bit units rather than bytes.
+.
+.
+.SH "NAMED SUBPATTERNS"
+.rs
+.sp
+The name-to-number translation table that is maintained for named subpatterns
+uses 16-bit characters. The \fBpcre16_get_stringtable_entries()\fP function
+returns the length of each entry in the table as the number of 16-bit data
+units.
+.
+.
+.SH "OPTION NAMES"
+.rs
+.sp
+There are two new general option names, PCRE_UTF16 and PCRE_NO_UTF16_CHECK,
+which correspond to PCRE_UTF8 and PCRE_NO_UTF8_CHECK in the 8-bit library. In
+fact, these new options define the same bits in the options word. There is a
+discussion about the
+.\" HTML <a href="pcreunicode.html#utf16strings">
+.\" </a>
+validity of UTF-16 strings
+.\"
+in the
+.\" HREF
+\fBpcreunicode\fP
+.\"
+page.
+.P
+For the \fBpcre16_config()\fP function there is an option PCRE_CONFIG_UTF16
+that returns 1 if UTF-16 support is configured, otherwise 0. If this option is
+given to \fBpcre_config()\fP or \fBpcre32_config()\fP, or if the
+PCRE_CONFIG_UTF8 or PCRE_CONFIG_UTF32 option is given to \fBpcre16_config()\fP,
+the result is the PCRE_ERROR_BADOPTION error.
+.
+.
+.SH "CHARACTER CODES"
+.rs
+.sp
+In 16-bit mode, when PCRE_UTF16 is not set, character values are treated in the
+same way as in 8-bit, non UTF-8 mode, except, of course, that they can range
+from 0 to 0xffff instead of 0 to 0xff. Character types for characters less than
+0xff can therefore be influenced by the locale in the same way as before.
+Characters greater than 0xff have only one case, and no "type" (such as letter
+or digit).
+.P
+In UTF-16 mode, the character code is Unicode, in the range 0 to 0x10ffff, with
+the exception of values in the range 0xd800 to 0xdfff because those are
+"surrogate" values that are used in pairs to encode values greater than 0xffff.
+.P
+A UTF-16 string can indicate its endianness by special code knows as a
+byte-order mark (BOM). The PCRE functions do not handle this, expecting strings
+to be in host byte order. A utility function called
+\fBpcre16_utf16_to_host_byte_order()\fP is provided to help with this (see
+above).
+.
+.
+.SH "ERROR NAMES"
+.rs
+.sp
+The errors PCRE_ERROR_BADUTF16_OFFSET and PCRE_ERROR_SHORTUTF16 correspond to
+their 8-bit counterparts. The error PCRE_ERROR_BADMODE is given when a compiled
+pattern is passed to a function that processes patterns in the other
+mode, for example, if a pattern compiled with \fBpcre_compile()\fP is passed to
+\fBpcre16_exec()\fP.
+.P
+There are new error codes whose names begin with PCRE_UTF16_ERR for invalid
+UTF-16 strings, corresponding to the PCRE_UTF8_ERR codes for UTF-8 strings that
+are described in the section entitled
+.\" HTML <a href="pcreapi.html#badutf8reasons">
+.\" </a>
+"Reason codes for invalid UTF-8 strings"
+.\"
+in the main
+.\" HREF
+\fBpcreapi\fP
+.\"
+page. The UTF-16 errors are:
+.sp
+  PCRE_UTF16_ERR1  Missing low surrogate at end of string
+  PCRE_UTF16_ERR2  Invalid low surrogate follows high surrogate
+  PCRE_UTF16_ERR3  Isolated low surrogate
+  PCRE_UTF16_ERR4  Non-character
+.
+.
+.SH "ERROR TEXTS"
+.rs
+.sp
+If there is an error while compiling a pattern, the error text that is passed
+back by \fBpcre16_compile()\fP or \fBpcre16_compile2()\fP is still an 8-bit
+character string, zero-terminated.
+.
+.
+.SH "CALLOUTS"
+.rs
+.sp
+The \fIsubject\fP and \fImark\fP fields in the callout block that is passed to
+a callout function point to 16-bit vectors.
+.
+.
+.SH "TESTING"
+.rs
+.sp
+The \fBpcretest\fP program continues to operate with 8-bit input and output
+files, but it can be used for testing the 16-bit library. If it is run with the
+command line option \fB-16\fP, patterns and subject strings are converted from
+8-bit to 16-bit before being passed to PCRE, and the 16-bit library functions
+are used instead of the 8-bit ones. Returned 16-bit strings are converted to
+8-bit for output. If both the 8-bit and the 32-bit libraries were not compiled,
+\fBpcretest\fP defaults to 16-bit and the \fB-16\fP option is ignored.
+.P
+When PCRE is being built, the \fBRunTest\fP script that is called by "make
+check" uses the \fBpcretest\fP \fB-C\fP option to discover which of the 8-bit,
+16-bit and 32-bit libraries has been built, and runs the tests appropriately.
+.
+.
+.SH "NOT SUPPORTED IN 16-BIT MODE"
+.rs
+.sp
+Not all the features of the 8-bit library are available with the 16-bit
+library. The C++ and POSIX wrapper functions support only the 8-bit library,
+and the \fBpcregrep\fP program is at present 8-bit only.
+.
+.
+.SH AUTHOR
+.rs
+.sp
+.nf
+Philip Hazel
+University Computing Service
+Cambridge CB2 3QH, England.
+.fi
+.
+.
+.SH REVISION
+.rs
+.sp
+.nf
+Last updated: 12 May 2013
+Copyright (c) 1997-2013 University of Cambridge.
+.fi
diff --git a/libs/Pcre16/docs/doc/pcre32.3 b/libs/Pcre16/docs/doc/pcre32.3
new file mode 100644
index 0000000000..7cde8c0877
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcre32.3
@@ -0,0 +1,369 @@
+.TH PCRE 3 "12 May 2013" "PCRE 8.33"
+.SH NAME
+PCRE - Perl-compatible regular expressions
+.sp
+.B #include <pcre.h>
+.
+.
+.SH "PCRE 32-BIT API BASIC FUNCTIONS"
+.rs
+.sp
+.nf
+.B pcre32 *pcre32_compile(PCRE_SPTR32 \fIpattern\fP, int \fIoptions\fP,
+.B "     const char **\fIerrptr\fP, int *\fIerroffset\fP,"
+.B "     const unsigned char *\fItableptr\fP);"
+.sp
+.B pcre32 *pcre32_compile2(PCRE_SPTR32 \fIpattern\fP, int \fIoptions\fP,
+.B "     int *\fIerrorcodeptr\fP,"
+.B "     const unsigned char *\fItableptr\fP);"
+.sp
+.B pcre32_extra *pcre32_study(const pcre32 *\fIcode\fP, int \fIoptions\fP,
+.B "     const char **\fIerrptr\fP);"
+.sp
+.B void pcre32_free_study(pcre32_extra *\fIextra\fP);
+.sp
+.B int pcre32_exec(const pcre32 *\fIcode\fP, "const pcre32_extra *\fIextra\fP,"
+.B "     PCRE_SPTR32 \fIsubject\fP, int \fIlength\fP, int \fIstartoffset\fP,"
+.B "     int \fIoptions\fP, int *\fIovector\fP, int \fIovecsize\fP);"
+.sp
+.B int pcre32_dfa_exec(const pcre32 *\fIcode\fP, "const pcre32_extra *\fIextra\fP,"
+.B "     PCRE_SPTR32 \fIsubject\fP, int \fIlength\fP, int \fIstartoffset\fP,"
+.B "     int \fIoptions\fP, int *\fIovector\fP, int \fIovecsize\fP,"
+.B "     int *\fIworkspace\fP, int \fIwscount\fP);"
+.fi
+.
+.
+.SH "PCRE 32-BIT API STRING EXTRACTION FUNCTIONS"
+.rs
+.sp
+.nf
+.B int pcre32_copy_named_substring(const pcre32 *\fIcode\fP,
+.B "     PCRE_SPTR32 \fIsubject\fP, int *\fIovector\fP,"
+.B "     int \fIstringcount\fP, PCRE_SPTR32 \fIstringname\fP,"
+.B "     PCRE_UCHAR32 *\fIbuffer\fP, int \fIbuffersize\fP);"
+.sp
+.B int pcre32_copy_substring(PCRE_SPTR32 \fIsubject\fP, int *\fIovector\fP,
+.B "     int \fIstringcount\fP, int \fIstringnumber\fP, PCRE_UCHAR32 *\fIbuffer\fP,"
+.B "     int \fIbuffersize\fP);"
+.sp
+.B int pcre32_get_named_substring(const pcre32 *\fIcode\fP,
+.B "     PCRE_SPTR32 \fIsubject\fP, int *\fIovector\fP,"
+.B "     int \fIstringcount\fP, PCRE_SPTR32 \fIstringname\fP,"
+.B "     PCRE_SPTR32 *\fIstringptr\fP);"
+.sp
+.B int pcre32_get_stringnumber(const pcre32 *\fIcode\fP,
+.B "     PCRE_SPTR32 \fIname\fP);"
+.sp
+.B int pcre32_get_stringtable_entries(const pcre32 *\fIcode\fP,
+.B "     PCRE_SPTR32 \fIname\fP, PCRE_UCHAR32 **\fIfirst\fP, PCRE_UCHAR32 **\fIlast\fP);"
+.sp
+.B int pcre32_get_substring(PCRE_SPTR32 \fIsubject\fP, int *\fIovector\fP,
+.B "     int \fIstringcount\fP, int \fIstringnumber\fP,"
+.B "     PCRE_SPTR32 *\fIstringptr\fP);"
+.sp
+.B int pcre32_get_substring_list(PCRE_SPTR32 \fIsubject\fP,
+.B "     int *\fIovector\fP, int \fIstringcount\fP, PCRE_SPTR32 **\fIlistptr\fP);"
+.sp
+.B void pcre32_free_substring(PCRE_SPTR32 \fIstringptr\fP);
+.sp
+.B void pcre32_free_substring_list(PCRE_SPTR32 *\fIstringptr\fP);
+.fi
+.
+.
+.SH "PCRE 32-BIT API AUXILIARY FUNCTIONS"
+.rs
+.sp
+.nf
+.B pcre32_jit_stack *pcre32_jit_stack_alloc(int \fIstartsize\fP, int \fImaxsize\fP);
+.sp
+.B void pcre32_jit_stack_free(pcre32_jit_stack *\fIstack\fP);
+.sp
+.B void pcre32_assign_jit_stack(pcre32_extra *\fIextra\fP,
+.B "     pcre32_jit_callback \fIcallback\fP, void *\fIdata\fP);"
+.sp
+.B const unsigned char *pcre32_maketables(void);
+.sp
+.B int pcre32_fullinfo(const pcre32 *\fIcode\fP, "const pcre32_extra *\fIextra\fP,"
+.B "     int \fIwhat\fP, void *\fIwhere\fP);"
+.sp
+.B int pcre32_refcount(pcre32 *\fIcode\fP, int \fIadjust\fP);
+.sp
+.B int pcre32_config(int \fIwhat\fP, void *\fIwhere\fP);
+.sp
+.B const char *pcre32_version(void);
+.sp
+.B int pcre32_pattern_to_host_byte_order(pcre32 *\fIcode\fP,
+.B "     pcre32_extra *\fIextra\fP, const unsigned char *\fItables\fP);"
+.fi
+.
+.
+.SH "PCRE 32-BIT API INDIRECTED FUNCTIONS"
+.rs
+.sp
+.nf
+.B void *(*pcre32_malloc)(size_t);
+.sp
+.B void (*pcre32_free)(void *);
+.sp
+.B void *(*pcre32_stack_malloc)(size_t);
+.sp
+.B void (*pcre32_stack_free)(void *);
+.sp
+.B int (*pcre32_callout)(pcre32_callout_block *);
+.fi
+.
+.
+.SH "PCRE 32-BIT API 32-BIT-ONLY FUNCTION"
+.rs
+.sp
+.nf
+.B int pcre32_utf32_to_host_byte_order(PCRE_UCHAR32 *\fIoutput\fP,
+.B "     PCRE_SPTR32 \fIinput\fP, int \fIlength\fP, int *\fIbyte_order\fP,"
+.B "     int \fIkeep_boms\fP);"
+.fi
+.
+.
+.SH "THE PCRE 32-BIT LIBRARY"
+.rs
+.sp
+Starting with release 8.32, it is possible to compile a PCRE library that
+supports 32-bit character strings, including UTF-32 strings, as well as or
+instead of the original 8-bit library. This work was done by Christian Persch,
+based on the work done by Zoltan Herczeg for the 16-bit library. All three
+libraries contain identical sets of functions, used in exactly the same way.
+Only the names of the functions and the data types of their arguments and
+results are different. To avoid over-complication and reduce the documentation
+maintenance load, most of the PCRE documentation describes the 8-bit library,
+with only occasional references to the 16-bit and 32-bit libraries. This page
+describes what is different when you use the 32-bit library.
+.P
+WARNING: A single application can be linked with all or any of the three
+libraries, but you must take care when processing any particular pattern
+to use functions from just one library. For example, if you want to study
+a pattern that was compiled with \fBpcre32_compile()\fP, you must do so
+with \fBpcre32_study()\fP, not \fBpcre_study()\fP, and you must free the
+study data with \fBpcre32_free_study()\fP.
+.
+.
+.SH "THE HEADER FILE"
+.rs
+.sp
+There is only one header file, \fBpcre.h\fP. It contains prototypes for all the
+functions in all libraries, as well as definitions of flags, structures, error
+codes, etc.
+.
+.
+.SH "THE LIBRARY NAME"
+.rs
+.sp
+In Unix-like systems, the 32-bit library is called \fBlibpcre32\fP, and can
+normally be accesss by adding \fB-lpcre32\fP to the command for linking an
+application that uses PCRE.
+.
+.
+.SH "STRING TYPES"
+.rs
+.sp
+In the 8-bit library, strings are passed to PCRE library functions as vectors
+of bytes with the C type "char *". In the 32-bit library, strings are passed as
+vectors of unsigned 32-bit quantities. The macro PCRE_UCHAR32 specifies an
+appropriate data type, and PCRE_SPTR32 is defined as "const PCRE_UCHAR32 *". In
+very many environments, "unsigned int" is a 32-bit data type. When PCRE is
+built, it defines PCRE_UCHAR32 as "unsigned int", but checks that it really is
+a 32-bit data type. If it is not, the build fails with an error message telling
+the maintainer to modify the definition appropriately.
+.
+.
+.SH "STRUCTURE TYPES"
+.rs
+.sp
+The types of the opaque structures that are used for compiled 32-bit patterns
+and JIT stacks are \fBpcre32\fP and \fBpcre32_jit_stack\fP respectively. The
+type of the user-accessible structure that is returned by \fBpcre32_study()\fP
+is \fBpcre32_extra\fP, and the type of the structure that is used for passing
+data to a callout function is \fBpcre32_callout_block\fP. These structures
+contain the same fields, with the same names, as their 8-bit counterparts. The
+only difference is that pointers to character strings are 32-bit instead of
+8-bit types.
+.
+.
+.SH "32-BIT FUNCTIONS"
+.rs
+.sp
+For every function in the 8-bit library there is a corresponding function in
+the 32-bit library with a name that starts with \fBpcre32_\fP instead of
+\fBpcre_\fP. The prototypes are listed above. In addition, there is one extra
+function, \fBpcre32_utf32_to_host_byte_order()\fP. This is a utility function
+that converts a UTF-32 character string to host byte order if necessary. The
+other 32-bit functions expect the strings they are passed to be in host byte
+order.
+.P
+The \fIinput\fP and \fIoutput\fP arguments of
+\fBpcre32_utf32_to_host_byte_order()\fP may point to the same address, that is,
+conversion in place is supported. The output buffer must be at least as long as
+the input.
+.P
+The \fIlength\fP argument specifies the number of 32-bit data units in the
+input string; a negative value specifies a zero-terminated string.
+.P
+If \fIbyte_order\fP is NULL, it is assumed that the string starts off in host
+byte order. This may be changed by byte-order marks (BOMs) anywhere in the
+string (commonly as the first character).
+.P
+If \fIbyte_order\fP is not NULL, a non-zero value of the integer to which it
+points means that the input starts off in host byte order, otherwise the
+opposite order is assumed. Again, BOMs in the string can change this. The final
+byte order is passed back at the end of processing.
+.P
+If \fIkeep_boms\fP is not zero, byte-order mark characters (0xfeff) are copied
+into the output string. Otherwise they are discarded.
+.P
+The result of the function is the number of 32-bit units placed into the output
+buffer, including the zero terminator if the string was zero-terminated.
+.
+.
+.SH "SUBJECT STRING OFFSETS"
+.rs
+.sp
+The lengths and starting offsets of subject strings must be specified in 32-bit
+data units, and the offsets within subject strings that are returned by the
+matching functions are in also 32-bit units rather than bytes.
+.
+.
+.SH "NAMED SUBPATTERNS"
+.rs
+.sp
+The name-to-number translation table that is maintained for named subpatterns
+uses 32-bit characters. The \fBpcre32_get_stringtable_entries()\fP function
+returns the length of each entry in the table as the number of 32-bit data
+units.
+.
+.
+.SH "OPTION NAMES"
+.rs
+.sp
+There are two new general option names, PCRE_UTF32 and PCRE_NO_UTF32_CHECK,
+which correspond to PCRE_UTF8 and PCRE_NO_UTF8_CHECK in the 8-bit library. In
+fact, these new options define the same bits in the options word. There is a
+discussion about the
+.\" HTML <a href="pcreunicode.html#utf32strings">
+.\" </a>
+validity of UTF-32 strings
+.\"
+in the
+.\" HREF
+\fBpcreunicode\fP
+.\"
+page.
+.P
+For the \fBpcre32_config()\fP function there is an option PCRE_CONFIG_UTF32
+that returns 1 if UTF-32 support is configured, otherwise 0. If this option is
+given to \fBpcre_config()\fP or \fBpcre16_config()\fP, or if the
+PCRE_CONFIG_UTF8 or PCRE_CONFIG_UTF16 option is given to \fBpcre32_config()\fP,
+the result is the PCRE_ERROR_BADOPTION error.
+.
+.
+.SH "CHARACTER CODES"
+.rs
+.sp
+In 32-bit mode, when PCRE_UTF32 is not set, character values are treated in the
+same way as in 8-bit, non UTF-8 mode, except, of course, that they can range
+from 0 to 0x7fffffff instead of 0 to 0xff. Character types for characters less
+than 0xff can therefore be influenced by the locale in the same way as before.
+Characters greater than 0xff have only one case, and no "type" (such as letter
+or digit).
+.P
+In UTF-32 mode, the character code is Unicode, in the range 0 to 0x10ffff, with
+the exception of values in the range 0xd800 to 0xdfff because those are
+"surrogate" values that are ill-formed in UTF-32.
+.P
+A UTF-32 string can indicate its endianness by special code knows as a
+byte-order mark (BOM). The PCRE functions do not handle this, expecting strings
+to be in host byte order. A utility function called
+\fBpcre32_utf32_to_host_byte_order()\fP is provided to help with this (see
+above).
+.
+.
+.SH "ERROR NAMES"
+.rs
+.sp
+The error PCRE_ERROR_BADUTF32 corresponds to its 8-bit counterpart.
+The error PCRE_ERROR_BADMODE is given when a compiled
+pattern is passed to a function that processes patterns in the other
+mode, for example, if a pattern compiled with \fBpcre_compile()\fP is passed to
+\fBpcre32_exec()\fP.
+.P
+There are new error codes whose names begin with PCRE_UTF32_ERR for invalid
+UTF-32 strings, corresponding to the PCRE_UTF8_ERR codes for UTF-8 strings that
+are described in the section entitled
+.\" HTML <a href="pcreapi.html#badutf8reasons">
+.\" </a>
+"Reason codes for invalid UTF-8 strings"
+.\"
+in the main
+.\" HREF
+\fBpcreapi\fP
+.\"
+page. The UTF-32 errors are:
+.sp
+  PCRE_UTF32_ERR1  Surrogate character (range from 0xd800 to 0xdfff)
+  PCRE_UTF32_ERR2  Non-character
+  PCRE_UTF32_ERR3  Character > 0x10ffff
+.
+.
+.SH "ERROR TEXTS"
+.rs
+.sp
+If there is an error while compiling a pattern, the error text that is passed
+back by \fBpcre32_compile()\fP or \fBpcre32_compile2()\fP is still an 8-bit
+character string, zero-terminated.
+.
+.
+.SH "CALLOUTS"
+.rs
+.sp
+The \fIsubject\fP and \fImark\fP fields in the callout block that is passed to
+a callout function point to 32-bit vectors.
+.
+.
+.SH "TESTING"
+.rs
+.sp
+The \fBpcretest\fP program continues to operate with 8-bit input and output
+files, but it can be used for testing the 32-bit library. If it is run with the
+command line option \fB-32\fP, patterns and subject strings are converted from
+8-bit to 32-bit before being passed to PCRE, and the 32-bit library functions
+are used instead of the 8-bit ones. Returned 32-bit strings are converted to
+8-bit for output. If both the 8-bit and the 16-bit libraries were not compiled,
+\fBpcretest\fP defaults to 32-bit and the \fB-32\fP option is ignored.
+.P
+When PCRE is being built, the \fBRunTest\fP script that is called by "make
+check" uses the \fBpcretest\fP \fB-C\fP option to discover which of the 8-bit,
+16-bit and 32-bit libraries has been built, and runs the tests appropriately.
+.
+.
+.SH "NOT SUPPORTED IN 32-BIT MODE"
+.rs
+.sp
+Not all the features of the 8-bit library are available with the 32-bit
+library. The C++ and POSIX wrapper functions support only the 8-bit library,
+and the \fBpcregrep\fP program is at present 8-bit only.
+.
+.
+.SH AUTHOR
+.rs
+.sp
+.nf
+Philip Hazel
+University Computing Service
+Cambridge CB2 3QH, England.
+.fi
+.
+.
+.SH REVISION
+.rs
+.sp
+.nf
+Last updated: 12 May 2013
+Copyright (c) 1997-2013 University of Cambridge.
+.fi
diff --git a/libs/Pcre16/docs/doc/pcre_assign_jit_stack.3 b/libs/Pcre16/docs/doc/pcre_assign_jit_stack.3
new file mode 100644
index 0000000000..0ecf6f2c60
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcre_assign_jit_stack.3
@@ -0,0 +1,59 @@
+.TH PCRE_ASSIGN_JIT_STACK 3 "24 June 2012" "PCRE 8.30"
+.SH NAME
+PCRE - Perl-compatible regular expressions
+.SH SYNOPSIS
+.rs
+.sp
+.B #include <pcre.h>
+.PP
+.nf
+.B void pcre_assign_jit_stack(pcre_extra *\fIextra\fP,
+.B "     pcre_jit_callback \fIcallback\fP, void *\fIdata\fP);"
+.sp
+.B void pcre16_assign_jit_stack(pcre16_extra *\fIextra\fP,
+.B "     pcre16_jit_callback \fIcallback\fP, void *\fIdata\fP);"
+.sp
+.B void pcre32_assign_jit_stack(pcre32_extra *\fIextra\fP,
+.B "     pcre32_jit_callback \fIcallback\fP, void *\fIdata\fP);"
+.fi
+.
+.SH DESCRIPTION
+.rs
+.sp
+This function provides control over the memory used as a stack at run-time by a
+call to \fBpcre[16|32]_exec()\fP with a pattern that has been successfully
+compiled with JIT optimization. The arguments are:
+.sp
+  extra     the data pointer returned by \fBpcre[16|32]_study()\fP
+  callback  a callback function
+  data      a JIT stack or a value to be passed to the callback
+              function
+.P
+If \fIcallback\fP is NULL and \fIdata\fP is NULL, an internal 32K block on
+the machine stack is used.
+.P
+If \fIcallback\fP is NULL and \fIdata\fP is not NULL, \fIdata\fP must
+be a valid JIT stack, the result of calling \fBpcre[16|32]_jit_stack_alloc()\fP.
+.P
+If \fIcallback\fP not NULL, it is called with \fIdata\fP as an argument at
+the start of matching, in order to set up a JIT stack. If the result is NULL,
+the internal 32K stack is used; otherwise the return value must be a valid JIT
+stack, the result of calling \fBpcre[16|32]_jit_stack_alloc()\fP.
+.P
+You may safely assign the same JIT stack to multiple patterns, as long as they
+are all matched in the same thread. In a multithread application, each thread
+must use its own JIT stack. For more details, see the
+.\" HREF
+\fBpcrejit\fP
+.\"
+page.
+.P
+There is a complete description of the PCRE native API in the
+.\" HREF
+\fBpcreapi\fP
+.\"
+page and a description of the POSIX API in the
+.\" HREF
+\fBpcreposix\fP
+.\"
+page.
diff --git a/libs/Pcre16/docs/doc/pcre_compile.3 b/libs/Pcre16/docs/doc/pcre_compile.3
new file mode 100644
index 0000000000..5c16ebe26d
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcre_compile.3
@@ -0,0 +1,96 @@
+.TH PCRE_COMPILE 3 "01 October 2013" "PCRE 8.34"
+.SH NAME
+PCRE - Perl-compatible regular expressions
+.SH SYNOPSIS
+.rs
+.sp
+.B #include <pcre.h>
+.PP
+.nf
+.B pcre *pcre_compile(const char *\fIpattern\fP, int \fIoptions\fP,
+.B "     const char **\fIerrptr\fP, int *\fIerroffset\fP,"
+.B "     const unsigned char *\fItableptr\fP);"
+.sp
+.B pcre16 *pcre16_compile(PCRE_SPTR16 \fIpattern\fP, int \fIoptions\fP,
+.B "     const char **\fIerrptr\fP, int *\fIerroffset\fP,"
+.B "     const unsigned char *\fItableptr\fP);"
+.sp
+.B pcre32 *pcre32_compile(PCRE_SPTR32 \fIpattern\fP, int \fIoptions\fP,
+.B "     const char **\fIerrptr\fP, int *\fIerroffset\fP,"
+.B "     const unsigned char *\fItableptr\fP);"
+.fi
+.
+.SH DESCRIPTION
+.rs
+.sp
+This function compiles a regular expression into an internal form. It is the
+same as \fBpcre[16|32]_compile2()\fP, except for the absence of the
+\fIerrorcodeptr\fP argument. Its arguments are:
+.sp
+  \fIpattern\fP       A zero-terminated string containing the
+                  regular expression to be compiled
+  \fIoptions\fP       Zero or more option bits
+  \fIerrptr\fP        Where to put an error message
+  \fIerroffset\fP     Offset in pattern where error was found
+  \fItableptr\fP      Pointer to character tables, or NULL to
+                  use the built-in default
+.sp
+The option bits are:
+.sp
+  PCRE_ANCHORED           Force pattern anchoring
+  PCRE_AUTO_CALLOUT       Compile automatic callouts
+  PCRE_BSR_ANYCRLF        \eR matches only CR, LF, or CRLF
+  PCRE_BSR_UNICODE        \eR matches all Unicode line endings
+  PCRE_CASELESS           Do caseless matching
+  PCRE_DOLLAR_ENDONLY     $ not to match newline at end
+  PCRE_DOTALL             . matches anything including NL
+  PCRE_DUPNAMES           Allow duplicate names for subpatterns
+  PCRE_EXTENDED           Ignore white space and # comments
+  PCRE_EXTRA              PCRE extra features
+                            (not much use currently)
+  PCRE_FIRSTLINE          Force matching to be before newline
+  PCRE_JAVASCRIPT_COMPAT  JavaScript compatibility
+  PCRE_MULTILINE          ^ and $ match newlines within data
+  PCRE_NEVER_UTF          Lock out UTF, e.g. via (*UTF)
+  PCRE_NEWLINE_ANY        Recognize any Unicode newline sequence
+  PCRE_NEWLINE_ANYCRLF    Recognize CR, LF, and CRLF as newline
+                            sequences
+  PCRE_NEWLINE_CR         Set CR as the newline sequence
+  PCRE_NEWLINE_CRLF       Set CRLF as the newline sequence
+  PCRE_NEWLINE_LF         Set LF as the newline sequence
+  PCRE_NO_AUTO_CAPTURE    Disable numbered capturing paren-
+                            theses (named ones available)
+  PCRE_NO_AUTO_POSSESS    Disable auto-possessification
+  PCRE_NO_START_OPTIMIZE  Disable match-time start optimizations
+  PCRE_NO_UTF16_CHECK     Do not check the pattern for UTF-16
+                            validity (only relevant if
+                            PCRE_UTF16 is set)
+  PCRE_NO_UTF32_CHECK     Do not check the pattern for UTF-32
+                            validity (only relevant if
+                            PCRE_UTF32 is set)
+  PCRE_NO_UTF8_CHECK      Do not check the pattern for UTF-8
+                            validity (only relevant if
+                            PCRE_UTF8 is set)
+  PCRE_UCP                Use Unicode properties for \ed, \ew, etc.
+  PCRE_UNGREEDY           Invert greediness of quantifiers
+  PCRE_UTF16              Run in \fBpcre16_compile()\fP UTF-16 mode
+  PCRE_UTF32              Run in \fBpcre32_compile()\fP UTF-32 mode
+  PCRE_UTF8               Run in \fBpcre_compile()\fP UTF-8 mode
+.sp
+PCRE must be built with UTF support in order to use PCRE_UTF8/16/32 and
+PCRE_NO_UTF8/16/32_CHECK, and with UCP support if PCRE_UCP is used.
+.P
+The yield of the function is a pointer to a private data structure that
+contains the compiled pattern, or NULL if an error was detected. Note that
+compiling regular expressions with one version of PCRE for use with a different
+version is not guaranteed to work and may cause crashes.
+.P
+There is a complete description of the PCRE native API in the
+.\" HREF
+\fBpcreapi\fP
+.\"
+page and a description of the POSIX API in the
+.\" HREF
+\fBpcreposix\fP
+.\"
+page.
diff --git a/libs/Pcre16/docs/doc/pcre_compile2.3 b/libs/Pcre16/docs/doc/pcre_compile2.3
new file mode 100644
index 0000000000..377420180e
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcre_compile2.3
@@ -0,0 +1,101 @@
+.TH PCRE_COMPILE2 3 "01 October 2013" "PCRE 8.34"
+.SH NAME
+PCRE - Perl-compatible regular expressions
+.SH SYNOPSIS
+.rs
+.sp
+.B #include <pcre.h>
+.PP
+.nf
+.B pcre *pcre_compile2(const char *\fIpattern\fP, int \fIoptions\fP,
+.B "     int *\fIerrorcodeptr\fP,"
+.B "     const char **\fIerrptr\fP, int *\fIerroffset\fP,"
+.B "     const unsigned char *\fItableptr\fP);"
+.sp
+.B pcre16 *pcre16_compile2(PCRE_SPTR16 \fIpattern\fP, int \fIoptions\fP,
+.B "     int *\fIerrorcodeptr\fP,"
+.B "     const char **\fIerrptr\fP, int *\fIerroffset\fP,"
+.B "     const unsigned char *\fItableptr\fP);"
+.sp
+.B pcre32 *pcre32_compile2(PCRE_SPTR32 \fIpattern\fP, int \fIoptions\fP,
+.B "     int *\fIerrorcodeptr\fP,£
+.B "     const char **\fIerrptr\fP, int *\fIerroffset\fP,"
+.B "     const unsigned char *\fItableptr\fP);"
+.fi
+.
+.SH DESCRIPTION
+.rs
+.sp
+This function compiles a regular expression into an internal form. It is the
+same as \fBpcre[16|32]_compile()\fP, except for the addition of the
+\fIerrorcodeptr\fP argument. The arguments are:
+.
+.sp
+  \fIpattern\fP       A zero-terminated string containing the
+                  regular expression to be compiled
+  \fIoptions\fP       Zero or more option bits
+  \fIerrorcodeptr\fP  Where to put an error code
+  \fIerrptr\fP        Where to put an error message
+  \fIerroffset\fP     Offset in pattern where error was found
+  \fItableptr\fP      Pointer to character tables, or NULL to
+                  use the built-in default
+.sp
+The option bits are:
+.sp
+  PCRE_ANCHORED           Force pattern anchoring
+  PCRE_AUTO_CALLOUT       Compile automatic callouts
+  PCRE_BSR_ANYCRLF        \eR matches only CR, LF, or CRLF
+  PCRE_BSR_UNICODE        \eR matches all Unicode line endings
+  PCRE_CASELESS           Do caseless matching
+  PCRE_DOLLAR_ENDONLY     $ not to match newline at end
+  PCRE_DOTALL             . matches anything including NL
+  PCRE_DUPNAMES           Allow duplicate names for subpatterns
+  PCRE_EXTENDED           Ignore white space and # comments
+  PCRE_EXTRA              PCRE extra features
+                            (not much use currently)
+  PCRE_FIRSTLINE          Force matching to be before newline
+  PCRE_JAVASCRIPT_COMPAT  JavaScript compatibility
+  PCRE_MULTILINE          ^ and $ match newlines within data
+  PCRE_NEVER_UTF          Lock out UTF, e.g. via (*UTF)
+  PCRE_NEWLINE_ANY        Recognize any Unicode newline sequence
+  PCRE_NEWLINE_ANYCRLF    Recognize CR, LF, and CRLF as newline
+                            sequences
+  PCRE_NEWLINE_CR         Set CR as the newline sequence
+  PCRE_NEWLINE_CRLF       Set CRLF as the newline sequence
+  PCRE_NEWLINE_LF         Set LF as the newline sequence
+  PCRE_NO_AUTO_CAPTURE    Disable numbered capturing paren-
+                            theses (named ones available)
+  PCRE_NO_AUTO_POSSESS    Disable auto-possessification
+  PCRE_NO_START_OPTIMIZE  Disable match-time start optimizations
+  PCRE_NO_UTF16_CHECK     Do not check the pattern for UTF-16
+                            validity (only relevant if
+                            PCRE_UTF16 is set)
+  PCRE_NO_UTF32_CHECK     Do not check the pattern for UTF-32
+                            validity (only relevant if
+                            PCRE_UTF32 is set)
+  PCRE_NO_UTF8_CHECK      Do not check the pattern for UTF-8
+                            validity (only relevant if
+                            PCRE_UTF8 is set)
+  PCRE_UCP                Use Unicode properties for \ed, \ew, etc.
+  PCRE_UNGREEDY           Invert greediness of quantifiers
+  PCRE_UTF16              Run \fBpcre16_compile()\fP in UTF-16 mode
+  PCRE_UTF32              Run \fBpcre32_compile()\fP in UTF-32 mode
+  PCRE_UTF8               Run \fBpcre_compile()\fP in UTF-8 mode
+.sp
+PCRE must be built with UTF support in order to use PCRE_UTF8/16/32 and
+PCRE_NO_UTF8/16/32_CHECK, and with UCP support if PCRE_UCP is used.
+.P
+The yield of the function is a pointer to a private data structure that
+contains the compiled pattern, or NULL if an error was detected. Note that
+compiling regular expressions with one version of PCRE for use with a different
+version is not guaranteed to work and may cause crashes.
+.P
+There is a complete description of the PCRE native API in the
+.\" HREF
+\fBpcreapi\fP
+.\"
+page and a description of the POSIX API in the
+.\" HREF
+\fBpcreposix\fP
+.\"
+page.
diff --git a/libs/Pcre16/docs/doc/pcre_config.3 b/libs/Pcre16/docs/doc/pcre_config.3
new file mode 100644
index 0000000000..d3de14bb73
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcre_config.3
@@ -0,0 +1,77 @@
+.TH PCRE_CONFIG 3 "05 November 2013" "PCRE 8.34"
+.SH NAME
+PCRE - Perl-compatible regular expressions
+.SH SYNOPSIS
+.rs
+.sp
+.B #include <pcre.h>
+.PP
+.SM
+.B int pcre_config(int \fIwhat\fP, void *\fIwhere\fP);
+.PP
+.B int pcre16_config(int \fIwhat\fP, void *\fIwhere\fP);
+.PP
+.B int pcre32_config(int \fIwhat\fP, void *\fIwhere\fP);
+.
+.SH DESCRIPTION
+.rs
+.sp
+This function makes it possible for a client program to find out which optional
+features are available in the version of the PCRE library it is using. The
+arguments are as follows:
+.sp
+  \fIwhat\fP     A code specifying what information is required
+  \fIwhere\fP    Points to where to put the data
+.sp
+The \fIwhere\fP argument must point to an integer variable, except for
+PCRE_CONFIG_MATCH_LIMIT and PCRE_CONFIG_MATCH_LIMIT_RECURSION, when it must
+point to an unsigned long integer. The available codes are:
+.sp
+  PCRE_CONFIG_JIT           Availability of just-in-time compiler
+                              support (1=yes 0=no)
+  PCRE_CONFIG_JITTARGET     String containing information about the
+                              target architecture for the JIT compiler,
+                              or NULL if there is no JIT support
+  PCRE_CONFIG_LINK_SIZE     Internal link size: 2, 3, or 4
+  PCRE_CONFIG_PARENS_LIMIT  Parentheses nesting limit
+  PCRE_CONFIG_MATCH_LIMIT   Internal resource limit
+  PCRE_CONFIG_MATCH_LIMIT_RECURSION
+                            Internal recursion depth limit
+  PCRE_CONFIG_NEWLINE       Value of the default newline sequence:
+                                13 (0x000d)    for CR
+                                10 (0x000a)    for LF
+                              3338 (0x0d0a)    for CRLF
+                                -2             for ANYCRLF
+                                -1             for ANY
+  PCRE_CONFIG_BSR           Indicates what \eR matches by default:
+                                 0             all Unicode line endings
+                                 1             CR, LF, or CRLF only
+  PCRE_CONFIG_POSIX_MALLOC_THRESHOLD
+                            Threshold of return slots, above which
+                              \fBmalloc()\fP is used by the POSIX API
+  PCRE_CONFIG_STACKRECURSE  Recursion implementation (1=stack 0=heap)
+  PCRE_CONFIG_UTF16         Availability of UTF-16 support (1=yes
+                               0=no); option for \fBpcre16_config()\fP
+  PCRE_CONFIG_UTF32         Availability of UTF-32 support (1=yes
+                               0=no); option for \fBpcre32_config()\fP
+  PCRE_CONFIG_UTF8          Availability of UTF-8 support (1=yes 0=no);
+                              option for \fBpcre_config()\fP
+  PCRE_CONFIG_UNICODE_PROPERTIES
+                            Availability of Unicode property support
+                              (1=yes 0=no)
+.sp
+The function yields 0 on success or PCRE_ERROR_BADOPTION otherwise. That error
+is also given if PCRE_CONFIG_UTF16 or PCRE_CONFIG_UTF32 is passed to
+\fBpcre_config()\fP, if PCRE_CONFIG_UTF8 or PCRE_CONFIG_UTF32 is passed to
+\fBpcre16_config()\fP, or if PCRE_CONFIG_UTF8 or PCRE_CONFIG_UTF16 is passed to
+\fBpcre32_config()\fP.
+.P
+There is a complete description of the PCRE native API in the
+.\" HREF
+\fBpcreapi\fP
+.\"
+page and a description of the POSIX API in the
+.\" HREF
+\fBpcreposix\fP
+.\"
+page.
diff --git a/libs/Pcre16/docs/doc/pcre_copy_named_substring.3 b/libs/Pcre16/docs/doc/pcre_copy_named_substring.3
new file mode 100644
index 0000000000..52582aecb2
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcre_copy_named_substring.3
@@ -0,0 +1,51 @@
+.TH PCRE_COPY_NAMED_SUBSTRING 3 "24 June 2012" "PCRE 8.30"
+.SH NAME
+PCRE - Perl-compatible regular expressions
+.SH SYNOPSIS
+.rs
+.sp
+.B #include <pcre.h>
+.PP
+.nf
+.B int pcre_copy_named_substring(const pcre *\fIcode\fP,
+.B "     const char *\fIsubject\fP, int *\fIovector\fP,"
+.B "     int \fIstringcount\fP, const char *\fIstringname\fP,"
+.B "     char *\fIbuffer\fP, int \fIbuffersize\fP);"
+.sp
+.B int pcre16_copy_named_substring(const pcre16 *\fIcode\fP,
+.B "     PCRE_SPTR16 \fIsubject\fP, int *\fIovector\fP,"
+.B "     int \fIstringcount\fP, PCRE_SPTR16 \fIstringname\fP,"
+.B "     PCRE_UCHAR16 *\fIbuffer\fP, int \fIbuffersize\fP);"
+.sp
+.B int pcre32_copy_named_substring(const pcre32 *\fIcode\fP,
+.B "     PCRE_SPTR32 \fIsubject\fP, int *\fIovector\fP,"
+.B "     int \fIstringcount\fP, PCRE_SPTR32 \fIstringname\fP,"
+.B "     PCRE_UCHAR32 *\fIbuffer\fP, int \fIbuffersize\fP);"
+.fi
+.
+.SH DESCRIPTION
+.rs
+.sp
+This is a convenience function for extracting a captured substring, identified
+by name, into a given buffer. The arguments are:
+.sp
+  \fIcode\fP          Pattern that was successfully matched
+  \fIsubject\fP       Subject that has been successfully matched
+  \fIovector\fP       Offset vector that \fBpcre[16|32]_exec()\fP used
+  \fIstringcount\fP   Value returned by \fBpcre[16|32]_exec()\fP
+  \fIstringname\fP    Name of the required substring
+  \fIbuffer\fP        Buffer to receive the string
+  \fIbuffersize\fP    Size of buffer
+.sp
+The yield is the length of the substring, PCRE_ERROR_NOMEMORY if the buffer was
+too small, or PCRE_ERROR_NOSUBSTRING if the string name is invalid.
+.P
+There is a complete description of the PCRE native API in the
+.\" HREF
+\fBpcreapi\fP
+.\"
+page and a description of the POSIX API in the
+.\" HREF
+\fBpcreposix\fP
+.\"
+page.
diff --git a/libs/Pcre16/docs/doc/pcre_copy_substring.3 b/libs/Pcre16/docs/doc/pcre_copy_substring.3
new file mode 100644
index 0000000000..83af6e800a
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcre_copy_substring.3
@@ -0,0 +1,47 @@
+.TH PCRE_COPY_SUBSTRING 3 "24 June 2012" "PCRE 8.30"
+.SH NAME
+PCRE - Perl-compatible regular expressions
+.SH SYNOPSIS
+.rs
+.sp
+.B #include <pcre.h>
+.PP
+.nf
+.B int pcre_copy_substring(const char *\fIsubject\fP, int *\fIovector\fP,
+.B "     int \fIstringcount\fP, int \fIstringnumber\fP, char *\fIbuffer\fP,"
+.B "     int \fIbuffersize\fP);"
+.sp
+.B int pcre16_copy_substring(PCRE_SPTR16 \fIsubject\fP, int *\fIovector\fP,
+.B "     int \fIstringcount\fP, int \fIstringnumber\fP, PCRE_UCHAR16 *\fIbuffer\fP,"
+.B "     int \fIbuffersize\fP);"
+.sp
+.B int pcre32_copy_substring(PCRE_SPTR32 \fIsubject\fP, int *\fIovector\fP,
+.B "     int \fIstringcount\fP, int \fIstringnumber\fP, PCRE_UCHAR32 *\fIbuffer\fP,"
+.B "     int \fIbuffersize\fP);"
+.fi
+.
+.SH DESCRIPTION
+.rs
+.sp
+This is a convenience function for extracting a captured substring into a given
+buffer. The arguments are:
+.sp
+  \fIsubject\fP       Subject that has been successfully matched
+  \fIovector\fP       Offset vector that \fBpcre[16|32]_exec()\fP used
+  \fIstringcount\fP   Value returned by \fBpcre[16|32]_exec()\fP
+  \fIstringnumber\fP  Number of the required substring
+  \fIbuffer\fP        Buffer to receive the string
+  \fIbuffersize\fP    Size of buffer
+.sp
+The yield is the length of the string, PCRE_ERROR_NOMEMORY if the buffer was
+too small, or PCRE_ERROR_NOSUBSTRING if the string number is invalid.
+.P
+There is a complete description of the PCRE native API in the
+.\" HREF
+\fBpcreapi\fP
+.\"
+page and a description of the POSIX API in the
+.\" HREF
+\fBpcreposix\fP
+.\"
+page.
diff --git a/libs/Pcre16/docs/doc/pcre_dfa_exec.3 b/libs/Pcre16/docs/doc/pcre_dfa_exec.3
new file mode 100644
index 0000000000..39c2e836da
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcre_dfa_exec.3
@@ -0,0 +1,118 @@
+.TH PCRE_DFA_EXEC 3 "12 May 2013" "PCRE 8.33"
+.SH NAME
+PCRE - Perl-compatible regular expressions
+.SH SYNOPSIS
+.rs
+.sp
+.B #include <pcre.h>
+.PP
+.nf
+.B int pcre_dfa_exec(const pcre *\fIcode\fP, "const pcre_extra *\fIextra\fP,"
+.B "     const char *\fIsubject\fP, int \fIlength\fP, int \fIstartoffset\fP,"
+.B "     int \fIoptions\fP, int *\fIovector\fP, int \fIovecsize\fP,"
+.B "     int *\fIworkspace\fP, int \fIwscount\fP);"
+.sp
+.B int pcre16_dfa_exec(const pcre16 *\fIcode\fP, "const pcre16_extra *\fIextra\fP,"
+.B "     PCRE_SPTR16 \fIsubject\fP, int \fIlength\fP, int \fIstartoffset\fP,"
+.B "     int \fIoptions\fP, int *\fIovector\fP, int \fIovecsize\fP,"
+.B "     int *\fIworkspace\fP, int \fIwscount\fP);"
+.sp
+.B int pcre32_dfa_exec(const pcre32 *\fIcode\fP, "const pcre32_extra *\fIextra\fP,"
+.B "     PCRE_SPTR32 \fIsubject\fP, int \fIlength\fP, int \fIstartoffset\fP,"
+.B "     int \fIoptions\fP, int *\fIovector\fP, int \fIovecsize\fP,"
+.B "     int *\fIworkspace\fP, int \fIwscount\fP);"
+.fi
+.
+.SH DESCRIPTION
+.rs
+.sp
+This function matches a compiled regular expression against a given subject
+string, using an alternative matching algorithm that scans the subject string
+just once (\fInot\fP Perl-compatible). Note that the main, Perl-compatible,
+matching function is \fBpcre[16|32]_exec()\fP. The arguments for this function
+are:
+.sp
+  \fIcode\fP         Points to the compiled pattern
+  \fIextra\fP        Points to an associated \fBpcre[16|32]_extra\fP structure,
+                 or is NULL
+  \fIsubject\fP      Points to the subject string
+  \fIlength\fP       Length of the subject string
+  \fIstartoffset\fP  Offset in the subject at which to start matching
+  \fIoptions\fP      Option bits
+  \fIovector\fP      Points to a vector of ints for result offsets
+  \fIovecsize\fP     Number of elements in the vector
+  \fIworkspace\fP    Points to a vector of ints used as working space
+  \fIwscount\fP      Number of elements in the vector
+.sp
+The units for \fIlength\fP and \fIstartoffset\fP are bytes for
+\fBpcre_exec()\fP, 16-bit data items for \fBpcre16_exec()\fP, and 32-bit items
+for \fBpcre32_exec()\fP. The options are:
+.sp
+  PCRE_ANCHORED          Match only at the first position
+  PCRE_BSR_ANYCRLF       \eR matches only CR, LF, or CRLF
+  PCRE_BSR_UNICODE       \eR matches all Unicode line endings
+  PCRE_NEWLINE_ANY       Recognize any Unicode newline sequence
+  PCRE_NEWLINE_ANYCRLF   Recognize CR, LF, & CRLF as newline sequences
+  PCRE_NEWLINE_CR        Recognize CR as the only newline sequence
+  PCRE_NEWLINE_CRLF      Recognize CRLF as the only newline sequence
+  PCRE_NEWLINE_LF        Recognize LF as the only newline sequence
+  PCRE_NOTBOL            Subject is not the beginning of a line
+  PCRE_NOTEOL            Subject is not the end of a line
+  PCRE_NOTEMPTY          An empty string is not a valid match
+  PCRE_NOTEMPTY_ATSTART  An empty string at the start of the subject
+                           is not a valid match
+  PCRE_NO_START_OPTIMIZE Do not do "start-match" optimizations
+  PCRE_NO_UTF16_CHECK    Do not check the subject for UTF-16
+                           validity (only relevant if PCRE_UTF16
+                           was set at compile time)
+  PCRE_NO_UTF32_CHECK    Do not check the subject for UTF-32
+                           validity (only relevant if PCRE_UTF32
+                           was set at compile time)
+  PCRE_NO_UTF8_CHECK     Do not check the subject for UTF-8
+                           validity (only relevant if PCRE_UTF8
+                           was set at compile time)
+  PCRE_PARTIAL           ) Return PCRE_ERROR_PARTIAL for a partial
+  PCRE_PARTIAL_SOFT      )   match if no full matches are found
+  PCRE_PARTIAL_HARD      Return PCRE_ERROR_PARTIAL for a partial match
+                           even if there is a full match as well
+  PCRE_DFA_SHORTEST      Return only the shortest match
+  PCRE_DFA_RESTART       Restart after a partial match
+.sp
+There are restrictions on what may appear in a pattern when using this matching
+function. Details are given in the
+.\" HREF
+\fBpcrematching\fP
+.\"
+documentation. For details of partial matching, see the
+.\" HREF
+\fBpcrepartial\fP
+.\"
+page.
+.P
+A \fBpcre[16|32]_extra\fP structure contains the following fields:
+.sp
+  \fIflags\fP            Bits indicating which fields are set
+  \fIstudy_data\fP       Opaque data from \fBpcre[16|32]_study()\fP
+  \fImatch_limit\fP      Limit on internal resource use
+  \fImatch_limit_recursion\fP  Limit on internal recursion depth
+  \fIcallout_data\fP     Opaque data passed back to callouts
+  \fItables\fP           Points to character tables or is NULL
+  \fImark\fP             For passing back a *MARK pointer
+  \fIexecutable_jit\fP   Opaque data from JIT compilation
+.sp
+The flag bits are PCRE_EXTRA_STUDY_DATA, PCRE_EXTRA_MATCH_LIMIT,
+PCRE_EXTRA_MATCH_LIMIT_RECURSION, PCRE_EXTRA_CALLOUT_DATA,
+PCRE_EXTRA_TABLES, PCRE_EXTRA_MARK and PCRE_EXTRA_EXECUTABLE_JIT. For this
+matching function, the \fImatch_limit\fP and \fImatch_limit_recursion\fP fields
+are not used, and must not be set. The PCRE_EXTRA_EXECUTABLE_JIT flag and
+the corresponding variable are ignored.
+.P
+There is a complete description of the PCRE native API in the
+.\" HREF
+\fBpcreapi\fP
+.\"
+page and a description of the POSIX API in the
+.\" HREF
+\fBpcreposix\fP
+.\"
+page.
diff --git a/libs/Pcre16/docs/doc/pcre_exec.3 b/libs/Pcre16/docs/doc/pcre_exec.3
new file mode 100644
index 0000000000..4686bd6de0
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcre_exec.3
@@ -0,0 +1,99 @@
+.TH PCRE_EXEC 3 "12 May 2013" "PCRE 8.33"
+.SH NAME
+PCRE - Perl-compatible regular expressions
+.SH SYNOPSIS
+.rs
+.sp
+.B #include <pcre.h>
+.PP
+.nf
+.B int pcre_exec(const pcre *\fIcode\fP, "const pcre_extra *\fIextra\fP,"
+.B "     const char *\fIsubject\fP, int \fIlength\fP, int \fIstartoffset\fP,"
+.B "     int \fIoptions\fP, int *\fIovector\fP, int \fIovecsize\fP);"
+.sp
+.B int pcre16_exec(const pcre16 *\fIcode\fP, "const pcre16_extra *\fIextra\fP,"
+.B "     PCRE_SPTR16 \fIsubject\fP, int \fIlength\fP, int \fIstartoffset\fP,"
+.B "     int \fIoptions\fP, int *\fIovector\fP, int \fIovecsize\fP);"
+.sp
+.B int pcre32_exec(const pcre32 *\fIcode\fP, "const pcre32_extra *\fIextra\fP,"
+.B "     PCRE_SPTR32 \fIsubject\fP, int \fIlength\fP, int \fIstartoffset\fP,"
+.B "     int \fIoptions\fP, int *\fIovector\fP, int \fIovecsize\fP);"
+.fi
+.
+.SH DESCRIPTION
+.rs
+.sp
+This function matches a compiled regular expression against a given subject
+string, using a matching algorithm that is similar to Perl's. It returns
+offsets to captured substrings. Its arguments are:
+.sp
+  \fIcode\fP         Points to the compiled pattern
+  \fIextra\fP        Points to an associated \fBpcre[16|32]_extra\fP structure,
+                 or is NULL
+  \fIsubject\fP      Points to the subject string
+  \fIlength\fP       Length of the subject string
+  \fIstartoffset\fP  Offset in the subject at which to start matching
+  \fIoptions\fP      Option bits
+  \fIovector\fP      Points to a vector of ints for result offsets
+  \fIovecsize\fP     Number of elements in the vector (a multiple of 3)
+.sp
+The units for \fIlength\fP and \fIstartoffset\fP are bytes for
+\fBpcre_exec()\fP, 16-bit data items for \fBpcre16_exec()\fP, and 32-bit items
+for \fBpcre32_exec()\fP. The options are:
+.sp
+  PCRE_ANCHORED          Match only at the first position
+  PCRE_BSR_ANYCRLF       \eR matches only CR, LF, or CRLF
+  PCRE_BSR_UNICODE       \eR matches all Unicode line endings
+  PCRE_NEWLINE_ANY       Recognize any Unicode newline sequence
+  PCRE_NEWLINE_ANYCRLF   Recognize CR, LF, & CRLF as newline sequences
+  PCRE_NEWLINE_CR        Recognize CR as the only newline sequence
+  PCRE_NEWLINE_CRLF      Recognize CRLF as the only newline sequence
+  PCRE_NEWLINE_LF        Recognize LF as the only newline sequence
+  PCRE_NOTBOL            Subject string is not the beginning of a line
+  PCRE_NOTEOL            Subject string is not the end of a line
+  PCRE_NOTEMPTY          An empty string is not a valid match
+  PCRE_NOTEMPTY_ATSTART  An empty string at the start of the subject
+                           is not a valid match
+  PCRE_NO_START_OPTIMIZE Do not do "start-match" optimizations
+  PCRE_NO_UTF16_CHECK    Do not check the subject for UTF-16
+                           validity (only relevant if PCRE_UTF16
+                           was set at compile time)
+  PCRE_NO_UTF32_CHECK    Do not check the subject for UTF-32
+                           validity (only relevant if PCRE_UTF32
+                           was set at compile time)
+  PCRE_NO_UTF8_CHECK     Do not check the subject for UTF-8
+                           validity (only relevant if PCRE_UTF8
+                           was set at compile time)
+  PCRE_PARTIAL           ) Return PCRE_ERROR_PARTIAL for a partial
+  PCRE_PARTIAL_SOFT      )   match if no full matches are found
+  PCRE_PARTIAL_HARD      Return PCRE_ERROR_PARTIAL for a partial match
+                           if that is found before a full match
+.sp
+For details of partial matching, see the
+.\" HREF
+\fBpcrepartial\fP
+.\"
+page. A \fBpcre_extra\fP structure contains the following fields:
+.sp
+  \fIflags\fP            Bits indicating which fields are set
+  \fIstudy_data\fP       Opaque data from \fBpcre[16|32]_study()\fP
+  \fImatch_limit\fP      Limit on internal resource use
+  \fImatch_limit_recursion\fP  Limit on internal recursion depth
+  \fIcallout_data\fP     Opaque data passed back to callouts
+  \fItables\fP           Points to character tables or is NULL
+  \fImark\fP             For passing back a *MARK pointer
+  \fIexecutable_jit\fP   Opaque data from JIT compilation
+.sp
+The flag bits are PCRE_EXTRA_STUDY_DATA, PCRE_EXTRA_MATCH_LIMIT,
+PCRE_EXTRA_MATCH_LIMIT_RECURSION, PCRE_EXTRA_CALLOUT_DATA,
+PCRE_EXTRA_TABLES, PCRE_EXTRA_MARK and PCRE_EXTRA_EXECUTABLE_JIT.
+.P
+There is a complete description of the PCRE native API in the
+.\" HREF
+\fBpcreapi\fP
+.\"
+page and a description of the POSIX API in the
+.\" HREF
+\fBpcreposix\fP
+.\"
+page.
diff --git a/libs/Pcre16/docs/doc/pcre_free_study.3 b/libs/Pcre16/docs/doc/pcre_free_study.3
new file mode 100644
index 0000000000..8826b73597
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcre_free_study.3
@@ -0,0 +1,31 @@
+.TH PCRE_FREE_STUDY 3 "24 June 2012" "PCRE 8.30"
+.SH NAME
+PCRE - Perl-compatible regular expressions
+.SH SYNOPSIS
+.rs
+.sp
+.B #include <pcre.h>
+.PP
+.SM
+.B void pcre_free_study(pcre_extra *\fIextra\fP);
+.PP
+.B void pcre16_free_study(pcre16_extra *\fIextra\fP);
+.PP
+.B void pcre32_free_study(pcre32_extra *\fIextra\fP);
+.
+.SH DESCRIPTION
+.rs
+.sp
+This function is used to free the memory used for the data generated by a call
+to \fBpcre[16|32]_study()\fP when it is no longer needed. The argument must be the
+result of such a call.
+.P
+There is a complete description of the PCRE native API in the
+.\" HREF
+\fBpcreapi\fP
+.\"
+page and a description of the POSIX API in the
+.\" HREF
+\fBpcreposix\fP
+.\"
+page.
diff --git a/libs/Pcre16/docs/doc/pcre_free_substring.3 b/libs/Pcre16/docs/doc/pcre_free_substring.3
new file mode 100644
index 0000000000..88c04019f4
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcre_free_substring.3
@@ -0,0 +1,31 @@
+.TH PCRE_FREE_SUBSTRING 3 "24 June 2012" "PCRE 8.30"
+.SH NAME
+PCRE - Perl-compatible regular expressions
+.SH SYNOPSIS
+.rs
+.sp
+.B #include <pcre.h>
+.PP
+.SM
+.B void pcre_free_substring(const char *\fIstringptr\fP);
+.PP
+.B void pcre16_free_substring(PCRE_SPTR16 \fIstringptr\fP);
+.PP
+.B void pcre32_free_substring(PCRE_SPTR32 \fIstringptr\fP);
+.
+.SH DESCRIPTION
+.rs
+.sp
+This is a convenience function for freeing the store obtained by a previous
+call to \fBpcre[16|32]_get_substring()\fP or \fBpcre[16|32]_get_named_substring()\fP.
+Its only argument is a pointer to the string.
+.P
+There is a complete description of the PCRE native API in the
+.\" HREF
+\fBpcreapi\fP
+.\"
+page and a description of the POSIX API in the
+.\" HREF
+\fBpcreposix\fP
+.\"
+page.
diff --git a/libs/Pcre16/docs/doc/pcre_free_substring_list.3 b/libs/Pcre16/docs/doc/pcre_free_substring_list.3
new file mode 100644
index 0000000000..248b4bd01b
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcre_free_substring_list.3
@@ -0,0 +1,31 @@
+.TH PCRE_FREE_SUBSTRING_LIST 3 "24 June 2012" "PCRE 8.30"
+.SH NAME
+PCRE - Perl-compatible regular expressions
+.SH SYNOPSIS
+.rs
+.sp
+.B #include <pcre.h>
+.PP
+.SM
+.B void pcre_free_substring_list(const char **\fIstringptr\fP);
+.PP
+.B void pcre16_free_substring_list(PCRE_SPTR16 *\fIstringptr\fP);
+.PP
+.B void pcre32_free_substring_list(PCRE_SPTR32 *\fIstringptr\fP);
+.
+.SH DESCRIPTION
+.rs
+.sp
+This is a convenience function for freeing the store obtained by a previous
+call to \fBpcre[16|32]_get_substring_list()\fP. Its only argument is a pointer to
+the list of string pointers.
+.P
+There is a complete description of the PCRE native API in the
+.\" HREF
+\fBpcreapi\fP
+.\"
+page and a description of the POSIX API in the
+.\" HREF
+\fBpcreposix\fP
+.\"
+page.
diff --git a/libs/Pcre16/docs/doc/pcre_fullinfo.3 b/libs/Pcre16/docs/doc/pcre_fullinfo.3
new file mode 100644
index 0000000000..01e2e92874
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcre_fullinfo.3
@@ -0,0 +1,93 @@
+.TH PCRE_FULLINFO 3 "24 June 2012" "PCRE 8.30"
+.SH NAME
+PCRE - Perl-compatible regular expressions
+.SH SYNOPSIS
+.rs
+.sp
+.B #include <pcre.h>
+.PP
+.nf
+.B int pcre_fullinfo(const pcre *\fIcode\fP, "const pcre_extra *\fIextra\fP,"
+.B "     int \fIwhat\fP, void *\fIwhere\fP);"
+.sp
+.B int pcre16_fullinfo(const pcre16 *\fIcode\fP, "const pcre16_extra *\fIextra\fP,"
+.B "     int \fIwhat\fP, void *\fIwhere\fP);"
+.sp
+.B int pcre32_fullinfo(const pcre32 *\fIcode\fP, "const pcre32_extra *\fIextra\fP,"
+.B "     int \fIwhat\fP, void *\fIwhere\fP);"
+.fi
+.
+.SH DESCRIPTION
+.rs
+.sp
+This function returns information about a compiled pattern. Its arguments are:
+.sp
+  \fIcode\fP                      Compiled regular expression
+  \fIextra\fP                     Result of \fBpcre[16|32]_study()\fP or NULL
+  \fIwhat\fP                      What information is required
+  \fIwhere\fP                     Where to put the information
+.sp
+The following information is available:
+.sp
+  PCRE_INFO_BACKREFMAX      Number of highest back reference
+  PCRE_INFO_CAPTURECOUNT    Number of capturing subpatterns
+  PCRE_INFO_DEFAULT_TABLES  Pointer to default tables
+  PCRE_INFO_FIRSTBYTE       Fixed first data unit for a match, or
+                              -1 for start of string
+                                 or after newline, or
+                              -2 otherwise
+  PCRE_INFO_FIRSTTABLE      Table of first data units (after studying)
+  PCRE_INFO_HASCRORLF       Return 1 if explicit CR or LF matches exist
+  PCRE_INFO_JCHANGED        Return 1 if (?J) or (?-J) was used
+  PCRE_INFO_JIT             Return 1 after successful JIT compilation
+  PCRE_INFO_JITSIZE         Size of JIT compiled code
+  PCRE_INFO_LASTLITERAL     Literal last data unit required
+  PCRE_INFO_MINLENGTH       Lower bound length of matching strings
+  PCRE_INFO_NAMECOUNT       Number of named subpatterns
+  PCRE_INFO_NAMEENTRYSIZE   Size of name table entry
+  PCRE_INFO_NAMETABLE       Pointer to name table
+  PCRE_INFO_OKPARTIAL       Return 1 if partial matching can be tried
+                              (always returns 1 after release 8.00)
+  PCRE_INFO_OPTIONS         Option bits used for compilation
+  PCRE_INFO_SIZE            Size of compiled pattern
+  PCRE_INFO_STUDYSIZE       Size of study data
+  PCRE_INFO_FIRSTCHARACTER      Fixed first data unit for a match
+  PCRE_INFO_FIRSTCHARACTERFLAGS Returns
+                                  1 if there is a first data character set, which can
+                                    then be retrieved using PCRE_INFO_FIRSTCHARACTER,
+                                  2 if the first character is at the start of the data
+                                    string or after a newline, and
+                                  0 otherwise
+  PCRE_INFO_REQUIREDCHAR      Literal last data unit required
+  PCRE_INFO_REQUIREDCHARFLAGS Returns 1 if the last data character is set (which can then
+                              be retrieved using PCRE_INFO_REQUIREDCHAR); 0 otherwise
+.sp
+The \fIwhere\fP argument must point to an integer variable, except for the
+following \fIwhat\fP values:
+.sp
+  PCRE_INFO_DEFAULT_TABLES  const unsigned char *
+  PCRE_INFO_FIRSTTABLE      const unsigned char *
+  PCRE_INFO_NAMETABLE       PCRE_SPTR16           (16-bit library)
+  PCRE_INFO_NAMETABLE       PCRE_SPTR32           (32-bit library)
+  PCRE_INFO_NAMETABLE       const unsigned char * (8-bit library)
+  PCRE_INFO_OPTIONS         unsigned long int
+  PCRE_INFO_SIZE            size_t
+  PCRE_INFO_FIRSTCHARACTER  uint32_t
+  PCRE_INFO_REQUIREDCHAR    uint32_t
+.sp
+The yield of the function is zero on success or:
+.sp
+  PCRE_ERROR_NULL           the argument \fIcode\fP was NULL
+                            the argument \fIwhere\fP was NULL
+  PCRE_ERROR_BADMAGIC       the "magic number" was not found
+  PCRE_ERROR_BADOPTION      the value of \fIwhat\fP was invalid
+.P
+There is a complete description of the PCRE native API in the
+.\" HREF
+\fBpcreapi\fP
+.\"
+page and a description of the POSIX API in the
+.\" HREF
+\fBpcreposix\fP
+.\"
+page.
diff --git a/libs/Pcre16/docs/doc/pcre_get_named_substring.3 b/libs/Pcre16/docs/doc/pcre_get_named_substring.3
new file mode 100644
index 0000000000..84d4ee7dbb
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcre_get_named_substring.3
@@ -0,0 +1,54 @@
+.TH PCRE_GET_NAMED_SUBSTRING 3 "24 June 2012" "PCRE 8.30"
+.SH NAME
+PCRE - Perl-compatible regular expressions
+.SH SYNOPSIS
+.rs
+.sp
+.B #include <pcre.h>
+.PP
+.nf
+.B int pcre_get_named_substring(const pcre *\fIcode\fP,
+.B "     const char *\fIsubject\fP, int *\fIovector\fP,"
+.B "     int \fIstringcount\fP, const char *\fIstringname\fP,"
+.B "     const char **\fIstringptr\fP);"
+.sp
+.B int pcre16_get_named_substring(const pcre16 *\fIcode\fP,
+.B "     PCRE_SPTR16 \fIsubject\fP, int *\fIovector\fP,"
+.B "     int \fIstringcount\fP, PCRE_SPTR16 \fIstringname\fP,"
+.B "     PCRE_SPTR16 *\fIstringptr\fP);"
+.sp
+.B int pcre32_get_named_substring(const pcre32 *\fIcode\fP,
+.B "     PCRE_SPTR32 \fIsubject\fP, int *\fIovector\fP,"
+.B "     int \fIstringcount\fP, PCRE_SPTR32 \fIstringname\fP,"
+.B "     PCRE_SPTR32 *\fIstringptr\fP);"
+.fi
+.
+.SH DESCRIPTION
+.rs
+.sp
+This is a convenience function for extracting a captured substring by name. The
+arguments are:
+.sp
+  \fIcode\fP          Compiled pattern
+  \fIsubject\fP       Subject that has been successfully matched
+  \fIovector\fP       Offset vector that \fBpcre[16|32]_exec()\fP used
+  \fIstringcount\fP   Value returned by \fBpcre[16|32]_exec()\fP
+  \fIstringname\fP    Name of the required substring
+  \fIstringptr\fP     Where to put the string pointer
+.sp
+The memory in which the substring is placed is obtained by calling
+\fBpcre[16|32]_malloc()\fP. The convenience function
+\fBpcre[16|32]_free_substring()\fP can be used to free it when it is no longer
+needed. The yield of the function is the length of the extracted substring,
+PCRE_ERROR_NOMEMORY if sufficient memory could not be obtained, or
+PCRE_ERROR_NOSUBSTRING if the string name is invalid.
+.P
+There is a complete description of the PCRE native API in the
+.\" HREF
+\fBpcreapi\fP
+.\"
+page and a description of the POSIX API in the
+.\" HREF
+\fBpcreposix\fP
+.\"
+page.
diff --git a/libs/Pcre16/docs/doc/pcre_get_stringnumber.3 b/libs/Pcre16/docs/doc/pcre_get_stringnumber.3
new file mode 100644
index 0000000000..9fc5291dc8
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcre_get_stringnumber.3
@@ -0,0 +1,43 @@
+.TH PCRE_GET_STRINGNUMBER 3 "24 June 2012" "PCRE 8.30"
+.SH NAME
+PCRE - Perl-compatible regular expressions
+.SH SYNOPSIS
+.rs
+.sp
+.B #include <pcre.h>
+.PP
+.nf
+.B int pcre_get_stringnumber(const pcre *\fIcode\fP,
+.B "     const char *\fIname\fP);"
+.sp
+.B int pcre16_get_stringnumber(const pcre16 *\fIcode\fP,
+.B "     PCRE_SPTR16 \fIname\fP);"
+.sp
+.B int pcre32_get_stringnumber(const pcre32 *\fIcode\fP,
+.B "     PCRE_SPTR32 \fIname\fP);"
+.fi
+.
+.SH DESCRIPTION
+.rs
+.sp
+This convenience function finds the number of a named substring capturing
+parenthesis in a compiled pattern. Its arguments are:
+.sp
+  \fIcode\fP    Compiled regular expression
+  \fIname\fP    Name whose number is required
+.sp
+The yield of the function is the number of the parenthesis if the name is
+found, or PCRE_ERROR_NOSUBSTRING otherwise. When duplicate names are allowed
+(PCRE_DUPNAMES is set), it is not defined which of the numbers is returned by
+\fBpcre[16|32]_get_stringnumber()\fP. You can obtain the complete list by calling
+\fBpcre[16|32]_get_stringtable_entries()\fP.
+.P
+There is a complete description of the PCRE native API in the
+.\" HREF
+\fBpcreapi\fP
+.\"
+page and a description of the POSIX API in the
+.\" HREF
+\fBpcreposix\fP
+.\"
+page.
diff --git a/libs/Pcre16/docs/doc/pcre_get_stringtable_entries.3 b/libs/Pcre16/docs/doc/pcre_get_stringtable_entries.3
new file mode 100644
index 0000000000..5c58c90c0e
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcre_get_stringtable_entries.3
@@ -0,0 +1,46 @@
+.TH PCRE_GET_STRINGTABLE_ENTRIES 3 "24 June 2012" "PCRE 8.30"
+.SH NAME
+PCRE - Perl-compatible regular expressions
+.SH SYNOPSIS
+.rs
+.sp
+.B #include <pcre.h>
+.PP
+.nf
+.B int pcre_get_stringtable_entries(const pcre *\fIcode\fP,
+.B "     const char *\fIname\fP, char **\fIfirst\fP, char **\fIlast\fP);"
+.sp
+.B int pcre16_get_stringtable_entries(const pcre16 *\fIcode\fP,
+.B "     PCRE_SPTR16 \fIname\fP, PCRE_UCHAR16 **\fIfirst\fP, PCRE_UCHAR16 **\fIlast\fP);"
+.sp
+.B int pcre32_get_stringtable_entries(const pcre32 *\fIcode\fP,
+.B "     PCRE_SPTR32 \fIname\fP, PCRE_UCHAR32 **\fIfirst\fP, PCRE_UCHAR32 **\fIlast\fP);"
+.fi
+.
+.SH DESCRIPTION
+.rs
+.sp
+This convenience function finds, for a compiled pattern, the first and last
+entries for a given name in the table that translates capturing parenthesis
+names into numbers. When names are required to be unique (PCRE_DUPNAMES is
+\fInot\fP set), it is usually easier to use \fBpcre[16|32]_get_stringnumber()\fP
+instead.
+.sp
+  \fIcode\fP    Compiled regular expression
+  \fIname\fP    Name whose entries required
+  \fIfirst\fP   Where to return a pointer to the first entry
+  \fIlast\fP    Where to return a pointer to the last entry
+.sp
+The yield of the function is the length of each entry, or
+PCRE_ERROR_NOSUBSTRING if none are found.
+.P
+There is a complete description of the PCRE native API, including the format of
+the table entries, in the
+.\" HREF
+\fBpcreapi\fP
+.\"
+page, and a description of the POSIX API in the
+.\" HREF
+\fBpcreposix\fP
+.\"
+page.
diff --git a/libs/Pcre16/docs/doc/pcre_get_substring.3 b/libs/Pcre16/docs/doc/pcre_get_substring.3
new file mode 100644
index 0000000000..1e62b2c0c6
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcre_get_substring.3
@@ -0,0 +1,50 @@
+.TH PCRE_GET_SUBSTRING 3 "24 June 2012" "PCRE 8.30"
+.SH NAME
+PCRE - Perl-compatible regular expressions
+.SH SYNOPSIS
+.rs
+.sp
+.B #include <pcre.h>
+.PP
+.nf
+.B int pcre_get_substring(const char *\fIsubject\fP, int *\fIovector\fP,
+.B "     int \fIstringcount\fP, int \fIstringnumber\fP,"
+.B "     const char **\fIstringptr\fP);"
+.sp
+.B int pcre16_get_substring(PCRE_SPTR16 \fIsubject\fP, int *\fIovector\fP,
+.B "     int \fIstringcount\fP, int \fIstringnumber\fP,"
+.B "     PCRE_SPTR16 *\fIstringptr\fP);"
+.sp
+.B int pcre32_get_substring(PCRE_SPTR32 \fIsubject\fP, int *\fIovector\fP,
+.B "     int \fIstringcount\fP, int \fIstringnumber\fP,"
+.B "     PCRE_SPTR32 *\fIstringptr\fP);"
+.fi
+.
+.SH DESCRIPTION
+.rs
+.sp
+This is a convenience function for extracting a captured substring. The
+arguments are:
+.sp
+  \fIsubject\fP       Subject that has been successfully matched
+  \fIovector\fP       Offset vector that \fBpcre[16|32]_exec()\fP used
+  \fIstringcount\fP   Value returned by \fBpcre[16|32]_exec()\fP
+  \fIstringnumber\fP  Number of the required substring
+  \fIstringptr\fP     Where to put the string pointer
+.sp
+The memory in which the substring is placed is obtained by calling
+\fBpcre[16|32]_malloc()\fP. The convenience function
+\fBpcre[16|32]_free_substring()\fP can be used to free it when it is no longer
+needed. The yield of the function is the length of the substring,
+PCRE_ERROR_NOMEMORY if sufficient memory could not be obtained, or
+PCRE_ERROR_NOSUBSTRING if the string number is invalid.
+.P
+There is a complete description of the PCRE native API in the
+.\" HREF
+\fBpcreapi\fP
+.\"
+page and a description of the POSIX API in the
+.\" HREF
+\fBpcreposix\fP
+.\"
+page.
diff --git a/libs/Pcre16/docs/doc/pcre_get_substring_list.3 b/libs/Pcre16/docs/doc/pcre_get_substring_list.3
new file mode 100644
index 0000000000..511a4a39d6
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcre_get_substring_list.3
@@ -0,0 +1,47 @@
+.TH PCRE_GET_SUBSTRING_LIST 3 "24 June 2012" "PCRE 8.30"
+.SH NAME
+PCRE - Perl-compatible regular expressions
+.SH SYNOPSIS
+.rs
+.sp
+.B #include <pcre.h>
+.PP
+.nf
+.B int pcre_get_substring_list(const char *\fIsubject\fP,
+.B "     int *\fIovector\fP, int \fIstringcount\fP, const char ***\fIlistptr\fP);"
+.sp
+.B int pcre16_get_substring_list(PCRE_SPTR16 \fIsubject\fP,
+.B "     int *\fIovector\fP, int \fIstringcount\fP, PCRE_SPTR16 **\fIlistptr\fP);"
+.sp
+.B int pcre32_get_substring_list(PCRE_SPTR32 \fIsubject\fP,
+.B "     int *\fIovector\fP, int \fIstringcount\fP, PCRE_SPTR32 **\fIlistptr\fP);"
+.fi
+.
+.SH DESCRIPTION
+.rs
+.sp
+This is a convenience function for extracting a list of all the captured
+substrings. The arguments are:
+.sp
+  \fIsubject\fP       Subject that has been successfully matched
+  \fIovector\fP       Offset vector that \fBpcre[16|32]_exec\fP used
+  \fIstringcount\fP   Value returned by \fBpcre[16|32]_exec\fP
+  \fIlistptr\fP       Where to put a pointer to the list
+.sp
+The memory in which the substrings and the list are placed is obtained by
+calling \fBpcre[16|32]_malloc()\fP. The convenience function
+\fBpcre[16|32]_free_substring_list()\fP can be used to free it when it is no
+longer needed. A pointer to a list of pointers is put in the variable whose
+address is in \fIlistptr\fP. The list is terminated by a NULL pointer. The
+yield of the function is zero on success or PCRE_ERROR_NOMEMORY if sufficient
+memory could not be obtained.
+.P
+There is a complete description of the PCRE native API in the
+.\" HREF
+\fBpcreapi\fP
+.\"
+page and a description of the POSIX API in the
+.\" HREF
+\fBpcreposix\fP
+.\"
+page.
diff --git a/libs/Pcre16/docs/doc/pcre_jit_exec.3 b/libs/Pcre16/docs/doc/pcre_jit_exec.3
new file mode 100644
index 0000000000..ba85168178
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcre_jit_exec.3
@@ -0,0 +1,96 @@
+.TH PCRE_EXEC 3 "31 October 2012" "PCRE 8.30"
+.SH NAME
+PCRE - Perl-compatible regular expressions
+.SH SYNOPSIS
+.rs
+.sp
+.B #include <pcre.h>
+.PP
+.nf
+.B int pcre_jit_exec(const pcre *\fIcode\fP, "const pcre_extra *\fIextra\fP,"
+.B "     const char *\fIsubject\fP, int \fIlength\fP, int \fIstartoffset\fP,"
+.B "     int \fIoptions\fP, int *\fIovector\fP, int \fIovecsize\fP,"
+.B "     pcre_jit_stack *\fIjstack\fP);"
+.sp
+.B int pcre16_jit_exec(const pcre16 *\fIcode\fP, "const pcre16_extra *\fIextra\fP,"
+.B "     PCRE_SPTR16 \fIsubject\fP, int \fIlength\fP, int \fIstartoffset\fP,"
+.B "     int \fIoptions\fP, int *\fIovector\fP, int \fIovecsize\fP,"
+.B "     pcre_jit_stack *\fIjstack\fP);"
+.sp
+.B int pcre32_jit_exec(const pcre32 *\fIcode\fP, "const pcre32_extra *\fIextra\fP,"
+.B "     PCRE_SPTR32 \fIsubject\fP, int \fIlength\fP, int \fIstartoffset\fP,"
+.B "     int \fIoptions\fP, int *\fIovector\fP, int \fIovecsize\fP,"
+.B "     pcre_jit_stack *\fIjstack\fP);"
+.fi
+.
+.SH DESCRIPTION
+.rs
+.sp
+This function matches a compiled regular expression that has been successfully
+studied with one of the JIT options against a given subject string, using a
+matching algorithm that is similar to Perl's. It is a "fast path" interface to
+JIT, and it bypasses some of the sanity checks that \fBpcre_exec()\fP applies.
+It returns offsets to captured substrings. Its arguments are:
+.sp
+  \fIcode\fP         Points to the compiled pattern
+  \fIextra\fP        Points to an associated \fBpcre[16|32]_extra\fP structure,
+                 or is NULL
+  \fIsubject\fP      Points to the subject string
+  \fIlength\fP       Length of the subject string, in bytes
+  \fIstartoffset\fP  Offset in bytes in the subject at which to
+                 start matching
+  \fIoptions\fP      Option bits
+  \fIovector\fP      Points to a vector of ints for result offsets
+  \fIovecsize\fP     Number of elements in the vector (a multiple of 3)
+  \fIjstack\fP       Pointer to a JIT stack
+.sp
+The allowed options are:
+.sp
+  PCRE_NOTBOL            Subject string is not the beginning of a line
+  PCRE_NOTEOL            Subject string is not the end of a line
+  PCRE_NOTEMPTY          An empty string is not a valid match
+  PCRE_NOTEMPTY_ATSTART  An empty string at the start of the subject
+                           is not a valid match
+  PCRE_NO_UTF16_CHECK    Do not check the subject for UTF-16
+                           validity (only relevant if PCRE_UTF16
+                           was set at compile time)
+  PCRE_NO_UTF32_CHECK    Do not check the subject for UTF-32
+                           validity (only relevant if PCRE_UTF32
+                           was set at compile time)
+  PCRE_NO_UTF8_CHECK     Do not check the subject for UTF-8
+                           validity (only relevant if PCRE_UTF8
+                           was set at compile time)
+  PCRE_PARTIAL           ) Return PCRE_ERROR_PARTIAL for a partial
+  PCRE_PARTIAL_SOFT      )   match if no full matches are found
+  PCRE_PARTIAL_HARD      Return PCRE_ERROR_PARTIAL for a partial match
+                           if that is found before a full match
+.sp
+However, the PCRE_NO_UTF[8|16|32]_CHECK options have no effect, as this check
+is never applied. For details of partial matching, see the
+.\" HREF
+\fBpcrepartial\fP
+.\"
+page. A \fBpcre_extra\fP structure contains the following fields:
+.sp
+  \fIflags\fP            Bits indicating which fields are set
+  \fIstudy_data\fP       Opaque data from \fBpcre[16|32]_study()\fP
+  \fImatch_limit\fP      Limit on internal resource use
+  \fImatch_limit_recursion\fP  Limit on internal recursion depth
+  \fIcallout_data\fP     Opaque data passed back to callouts
+  \fItables\fP           Points to character tables or is NULL
+  \fImark\fP             For passing back a *MARK pointer
+  \fIexecutable_jit\fP   Opaque data from JIT compilation
+.sp
+The flag bits are PCRE_EXTRA_STUDY_DATA, PCRE_EXTRA_MATCH_LIMIT,
+PCRE_EXTRA_MATCH_LIMIT_RECURSION, PCRE_EXTRA_CALLOUT_DATA,
+PCRE_EXTRA_TABLES, PCRE_EXTRA_MARK and PCRE_EXTRA_EXECUTABLE_JIT.
+.P
+There is a complete description of the PCRE native API in the
+.\" HREF
+\fBpcreapi\fP
+.\"
+page and a description of the JIT API in the
+.\" HREF
+\fBpcrejit\fP
+.\"
+page.
diff --git a/libs/Pcre16/docs/doc/pcre_jit_stack_alloc.3 b/libs/Pcre16/docs/doc/pcre_jit_stack_alloc.3
new file mode 100644
index 0000000000..11c97a0fc8
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcre_jit_stack_alloc.3
@@ -0,0 +1,43 @@
+.TH PCRE_JIT_STACK_ALLOC 3 "24 June 2012" "PCRE 8.30"
+.SH NAME
+PCRE - Perl-compatible regular expressions
+.SH SYNOPSIS
+.rs
+.sp
+.B #include <pcre.h>
+.PP
+.nf
+.B pcre_jit_stack *pcre_jit_stack_alloc(int \fIstartsize\fP,
+.B "     int \fImaxsize\fP);"
+.sp
+.B pcre16_jit_stack *pcre16_jit_stack_alloc(int \fIstartsize\fP,
+.B "     int \fImaxsize\fP);"
+.sp
+.B pcre32_jit_stack *pcre32_jit_stack_alloc(int \fIstartsize\fP,
+.B "     int \fImaxsize\fP);"
+.fi
+.
+.SH DESCRIPTION
+.rs
+.sp
+This function is used to create a stack for use by the code compiled by the JIT
+optimization of \fBpcre[16|32]_study()\fP. The arguments are a starting size for
+the stack, and a maximum size to which it is allowed to grow. The result can be
+passed to the JIT run-time code by \fBpcre[16|32]_assign_jit_stack()\fP, or that
+function can set up a callback for obtaining a stack. A maximum stack size of
+512K to 1M should be more than enough for any pattern. For more details, see
+the
+.\" HREF
+\fBpcrejit\fP
+.\"
+page.
+.P
+There is a complete description of the PCRE native API in the
+.\" HREF
+\fBpcreapi\fP
+.\"
+page and a description of the POSIX API in the
+.\" HREF
+\fBpcreposix\fP
+.\"
+page.
diff --git a/libs/Pcre16/docs/doc/pcre_jit_stack_free.3 b/libs/Pcre16/docs/doc/pcre_jit_stack_free.3
new file mode 100644
index 0000000000..494724e844
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcre_jit_stack_free.3
@@ -0,0 +1,35 @@
+.TH PCRE_JIT_STACK_FREE 3 "24 June 2012" "PCRE 8.30"
+.SH NAME
+PCRE - Perl-compatible regular expressions
+.SH SYNOPSIS
+.rs
+.sp
+.B #include <pcre.h>
+.PP
+.SM
+.B void pcre_jit_stack_free(pcre_jit_stack *\fIstack\fP);
+.PP
+.B void pcre16_jit_stack_free(pcre16_jit_stack *\fIstack\fP);
+.PP
+.B void pcre32_jit_stack_free(pcre32_jit_stack *\fIstack\fP);
+.
+.SH DESCRIPTION
+.rs
+.sp
+This function is used to free a JIT stack that was created by
+\fBpcre[16|32]_jit_stack_alloc()\fP when it is no longer needed. For more details,
+see the
+.\" HREF
+\fBpcrejit\fP
+.\"
+page.
+.P
+There is a complete description of the PCRE native API in the
+.\" HREF
+\fBpcreapi\fP
+.\"
+page and a description of the POSIX API in the
+.\" HREF
+\fBpcreposix\fP
+.\"
+page.
diff --git a/libs/Pcre16/docs/doc/pcre_maketables.3 b/libs/Pcre16/docs/doc/pcre_maketables.3
new file mode 100644
index 0000000000..b2c3d23aa6
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcre_maketables.3
@@ -0,0 +1,33 @@
+.TH PCRE_MAKETABLES 3 "24 June 2012" "PCRE 8.30"
+.SH NAME
+PCRE - Perl-compatible regular expressions
+.SH SYNOPSIS
+.rs
+.sp
+.B #include <pcre.h>
+.PP
+.SM
+.B const unsigned char *pcre_maketables(void);
+.PP
+.B const unsigned char *pcre16_maketables(void);
+.PP
+.B const unsigned char *pcre32_maketables(void);
+.
+.SH DESCRIPTION
+.rs
+.sp
+This function builds a set of character tables for character values less than
+256. These can be passed to \fBpcre[16|32]_compile()\fP to override PCRE's
+internal, built-in tables (which were made by \fBpcre[16|32]_maketables()\fP when
+PCRE was compiled). You might want to do this if you are using a non-standard
+locale. The function yields a pointer to the tables.
+.P
+There is a complete description of the PCRE native API in the
+.\" HREF
+\fBpcreapi\fP
+.\"
+page and a description of the POSIX API in the
+.\" HREF
+\fBpcreposix\fP
+.\"
+page.
diff --git a/libs/Pcre16/docs/doc/pcre_pattern_to_host_byte_order.3 b/libs/Pcre16/docs/doc/pcre_pattern_to_host_byte_order.3
new file mode 100644
index 0000000000..b0c41c38e8
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcre_pattern_to_host_byte_order.3
@@ -0,0 +1,44 @@
+.TH PCRE_PATTERN_TO_HOST_BYTE_ORDER 3 "24 June 2012" "PCRE 8.30"
+.SH NAME
+PCRE - Perl-compatible regular expressions
+.SH SYNOPSIS
+.rs
+.sp
+.B #include <pcre.h>
+.PP
+.nf
+.B int pcre_pattern_to_host_byte_order(pcre *\fIcode\fP,
+.B "     pcre_extra *\fIextra\fP, const unsigned char *\fItables\fP);"
+.sp
+.B int pcre16_pattern_to_host_byte_order(pcre16 *\fIcode\fP,
+.B "     pcre16_extra *\fIextra\fP, const unsigned char *\fItables\fP);"
+.sp
+.B int pcre32_pattern_to_host_byte_order(pcre32 *\fIcode\fP,
+.B "     pcre32_extra *\fIextra\fP, const unsigned char *\fItables\fP);"
+.fi
+.
+.SH DESCRIPTION
+.rs
+.sp
+This function ensures that the bytes in 2-byte and 4-byte values in a compiled
+pattern are in the correct order for the current host. It is useful when a
+pattern that has been compiled on one host is transferred to another that might
+have different endianness. The arguments are:
+.sp
+  \fIcode\fP         A compiled regular expression
+  \fIextra\fP        Points to an associated \fBpcre[16|32]_extra\fP structure,
+                 or is NULL
+  \fItables\fP       Pointer to character tables, or NULL to
+                 set the built-in default
+.sp
+The result is 0 for success, a negative PCRE_ERROR_xxx value otherwise.
+.P
+There is a complete description of the PCRE native API in the
+.\" HREF
+\fBpcreapi\fP
+.\"
+page and a description of the POSIX API in the
+.\" HREF
+\fBpcreposix\fP
+.\"
+page.
diff --git a/libs/Pcre16/docs/doc/pcre_refcount.3 b/libs/Pcre16/docs/doc/pcre_refcount.3
new file mode 100644
index 0000000000..45a41fef6a
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcre_refcount.3
@@ -0,0 +1,36 @@
+.TH PCRE_REFCOUNT 3 "24 June 2012" "PCRE 8.30"
+.SH NAME
+PCRE - Perl-compatible regular expressions
+.SH SYNOPSIS
+.rs
+.sp
+.B #include <pcre.h>
+.PP
+.SM
+.B int pcre_refcount(pcre *\fIcode\fP, int \fIadjust\fP);
+.PP
+.B int pcre16_refcount(pcre16 *\fIcode\fP, int \fIadjust\fP);
+.PP
+.B int pcre32_refcount(pcre32 *\fIcode\fP, int \fIadjust\fP);
+.
+.SH DESCRIPTION
+.rs
+.sp
+This function is used to maintain a reference count inside a data block that
+contains a compiled pattern. Its arguments are:
+.sp
+  \fIcode\fP                      Compiled regular expression
+  \fIadjust\fP                    Adjustment to reference value
+.sp
+The yield of the function is the adjusted reference value, which is constrained
+to lie between 0 and 65535.
+.P
+There is a complete description of the PCRE native API in the
+.\" HREF
+\fBpcreapi\fP
+.\"
+page and a description of the POSIX API in the
+.\" HREF
+\fBpcreposix\fP
+.\"
+page.
diff --git a/libs/Pcre16/docs/doc/pcre_study.3 b/libs/Pcre16/docs/doc/pcre_study.3
new file mode 100644
index 0000000000..1200e0a668
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcre_study.3
@@ -0,0 +1,54 @@
+.TH PCRE_STUDY 3 " 24 June 2012" "PCRE 8.30"
+.SH NAME
+PCRE - Perl-compatible regular expressions
+.SH SYNOPSIS
+.rs
+.sp
+.B #include <pcre.h>
+.PP
+.nf
+.B pcre_extra *pcre_study(const pcre *\fIcode\fP, int \fIoptions\fP,
+.B "     const char **\fIerrptr\fP);"
+.sp
+.B pcre16_extra *pcre16_study(const pcre16 *\fIcode\fP, int \fIoptions\fP,
+.B "     const char **\fIerrptr\fP);"
+.sp
+.B pcre32_extra *pcre32_study(const pcre32 *\fIcode\fP, int \fIoptions\fP,
+.B "     const char **\fIerrptr\fP);"
+.fi
+.
+.SH DESCRIPTION
+.rs
+.sp
+This function studies a compiled pattern, to see if additional information can
+be extracted that might speed up matching. Its arguments are:
+.sp
+  \fIcode\fP       A compiled regular expression
+  \fIoptions\fP    Options for \fBpcre[16|32]_study()\fP
+  \fIerrptr\fP     Where to put an error message
+.sp
+If the function succeeds, it returns a value that can be passed to
+\fBpcre[16|32]_exec()\fP or \fBpcre[16|32]_dfa_exec()\fP via their \fIextra\fP
+arguments.
+.P
+If the function returns NULL, either it could not find any additional
+information, or there was an error. You can tell the difference by looking at
+the error value. It is NULL in first case.
+.P
+The only option is PCRE_STUDY_JIT_COMPILE. It requests just-in-time compilation
+if possible. If PCRE has been compiled without JIT support, this option is
+ignored. See the
+.\" HREF
+\fBpcrejit\fP
+.\"
+page for further details.
+.P
+There is a complete description of the PCRE native API in the
+.\" HREF
+\fBpcreapi\fP
+.\"
+page and a description of the POSIX API in the
+.\" HREF
+\fBpcreposix\fP
+.\"
+page.
diff --git a/libs/Pcre16/docs/doc/pcre_utf16_to_host_byte_order.3 b/libs/Pcre16/docs/doc/pcre_utf16_to_host_byte_order.3
new file mode 100644
index 0000000000..1851b619da
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcre_utf16_to_host_byte_order.3
@@ -0,0 +1,45 @@
+.TH PCRE_UTF16_TO_HOST_BYTE_ORDER 3 "21 January 2012" "PCRE 8.30"
+.SH NAME
+PCRE - Perl-compatible regular expressions
+.SH SYNOPSIS
+.rs
+.sp
+.B #include <pcre.h>
+.PP
+.nf
+.B int pcre16_utf16_to_host_byte_order(PCRE_UCHAR16 *\fIoutput\fP,
+.B "     PCRE_SPTR16 \fIinput\fP, int \fIlength\fP, int *\fIhost_byte_order\fP,"
+.B "     int \fIkeep_boms\fP);"
+.fi
+.
+.
+.SH DESCRIPTION
+.rs
+.sp
+This function, which exists only in the 16-bit library, converts a UTF-16
+string to the correct order for the current host, taking account of any byte
+order marks (BOMs) within the string. Its arguments are:
+.sp
+  \fIoutput\fP           pointer to output buffer, may be the same as \fIinput\fP
+  \fIinput\fP            pointer to input buffer
+  \fIlength\fP           number of 16-bit units in the input, or negative for
+                     a zero-terminated string
+  \fIhost_byte_order\fP  a NULL value or a non-zero value pointed to means
+                     start in host byte order
+  \fIkeep_boms\fP        if non-zero, BOMs are copied to the output string
+.sp
+The result of the function is the number of 16-bit units placed into the output
+buffer, including the zero terminator if the string was zero-terminated.
+.P
+If \fIhost_byte_order\fP is not NULL, it is set to indicate the byte order that
+is current at the end of the string.
+.P
+There is a complete description of the PCRE native API in the
+.\" HREF
+\fBpcreapi\fP
+.\"
+page and a description of the POSIX API in the
+.\" HREF
+\fBpcreposix\fP
+.\"
+page.
diff --git a/libs/Pcre16/docs/doc/pcre_utf32_to_host_byte_order.3 b/libs/Pcre16/docs/doc/pcre_utf32_to_host_byte_order.3
new file mode 100644
index 0000000000..a415dcf5fa
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcre_utf32_to_host_byte_order.3
@@ -0,0 +1,45 @@
+.TH PCRE_UTF32_TO_HOST_BYTE_ORDER 3 "24 June 2012" "PCRE 8.30"
+.SH NAME
+PCRE - Perl-compatible regular expressions
+.SH SYNOPSIS
+.rs
+.sp
+.B #include <pcre.h>
+.PP
+.nf
+.B int pcre32_utf32_to_host_byte_order(PCRE_UCHAR32 *\fIoutput\fP,
+.B "     PCRE_SPTR32 \fIinput\fP, int \fIlength\fP, int *\fIhost_byte_order\fP,"
+.B "     int \fIkeep_boms\fP);"
+.fi
+.
+.
+.SH DESCRIPTION
+.rs
+.sp
+This function, which exists only in the 32-bit library, converts a UTF-32
+string to the correct order for the current host, taking account of any byte
+order marks (BOMs) within the string. Its arguments are:
+.sp
+  \fIoutput\fP           pointer to output buffer, may be the same as \fIinput\fP
+  \fIinput\fP            pointer to input buffer
+  \fIlength\fP           number of 32-bit units in the input, or negative for
+                     a zero-terminated string
+  \fIhost_byte_order\fP  a NULL value or a non-zero value pointed to means
+                     start in host byte order
+  \fIkeep_boms\fP        if non-zero, BOMs are copied to the output string
+.sp
+The result of the function is the number of 32-bit units placed into the output
+buffer, including the zero terminator if the string was zero-terminated.
+.P
+If \fIhost_byte_order\fP is not NULL, it is set to indicate the byte order that
+is current at the end of the string.
+.P
+There is a complete description of the PCRE native API in the
+.\" HREF
+\fBpcreapi\fP
+.\"
+page and a description of the POSIX API in the
+.\" HREF
+\fBpcreposix\fP
+.\"
+page.
diff --git a/libs/Pcre16/docs/doc/pcre_version.3 b/libs/Pcre16/docs/doc/pcre_version.3
new file mode 100644
index 0000000000..0f4973f9c7
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcre_version.3
@@ -0,0 +1,31 @@
+.TH PCRE_VERSION 3 "24 June 2012" "PCRE 8.30"
+.SH NAME
+PCRE - Perl-compatible regular expressions
+.SH SYNOPSIS
+.rs
+.sp
+.B #include <pcre.h>
+.PP
+.SM
+.B const char *pcre_version(void);
+.PP
+.B const char *pcre16_version(void);
+.PP
+.B const char *pcre32_version(void);
+.
+.SH DESCRIPTION
+.rs
+.sp
+This function (even in the 16-bit and 32-bit libraries) returns a
+zero-terminated, 8-bit character string that gives the version number of the
+PCRE library and the date of its release.
+.P
+There is a complete description of the PCRE native API in the
+.\" HREF
+\fBpcreapi\fP
+.\"
+page and a description of the POSIX API in the
+.\" HREF
+\fBpcreposix\fP
+.\"
+page.
diff --git a/libs/Pcre16/docs/doc/pcreapi.3 b/libs/Pcre16/docs/doc/pcreapi.3
new file mode 100644
index 0000000000..ab3eaa0b52
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcreapi.3
@@ -0,0 +1,2919 @@
+.TH PCREAPI 3 "09 February 2014" "PCRE 8.35"
+.SH NAME
+PCRE - Perl-compatible regular expressions
+.sp
+.B #include <pcre.h>
+.
+.
+.SH "PCRE NATIVE API BASIC FUNCTIONS"
+.rs
+.sp
+.nf
+.B pcre *pcre_compile(const char *\fIpattern\fP, int \fIoptions\fP,
+.B "     const char **\fIerrptr\fP, int *\fIerroffset\fP,"
+.B "     const unsigned char *\fItableptr\fP);"
+.sp
+.B pcre *pcre_compile2(const char *\fIpattern\fP, int \fIoptions\fP,
+.B "     int *\fIerrorcodeptr\fP,"
+.B "     const char **\fIerrptr\fP, int *\fIerroffset\fP,"
+.B "     const unsigned char *\fItableptr\fP);"
+.sp
+.B pcre_extra *pcre_study(const pcre *\fIcode\fP, int \fIoptions\fP,
+.B "     const char **\fIerrptr\fP);"
+.sp
+.B void pcre_free_study(pcre_extra *\fIextra\fP);
+.sp
+.B int pcre_exec(const pcre *\fIcode\fP, "const pcre_extra *\fIextra\fP,"
+.B "     const char *\fIsubject\fP, int \fIlength\fP, int \fIstartoffset\fP,"
+.B "     int \fIoptions\fP, int *\fIovector\fP, int \fIovecsize\fP);"
+.sp
+.B int pcre_dfa_exec(const pcre *\fIcode\fP, "const pcre_extra *\fIextra\fP,"
+.B "     const char *\fIsubject\fP, int \fIlength\fP, int \fIstartoffset\fP,"
+.B "     int \fIoptions\fP, int *\fIovector\fP, int \fIovecsize\fP,"
+.B "     int *\fIworkspace\fP, int \fIwscount\fP);"
+.fi
+.
+.
+.SH "PCRE NATIVE API STRING EXTRACTION FUNCTIONS"
+.rs
+.sp
+.nf
+.B int pcre_copy_named_substring(const pcre *\fIcode\fP,
+.B "     const char *\fIsubject\fP, int *\fIovector\fP,"
+.B "     int \fIstringcount\fP, const char *\fIstringname\fP,"
+.B "     char *\fIbuffer\fP, int \fIbuffersize\fP);"
+.sp
+.B int pcre_copy_substring(const char *\fIsubject\fP, int *\fIovector\fP,
+.B "     int \fIstringcount\fP, int \fIstringnumber\fP, char *\fIbuffer\fP,"
+.B "     int \fIbuffersize\fP);"
+.sp
+.B int pcre_get_named_substring(const pcre *\fIcode\fP,
+.B "     const char *\fIsubject\fP, int *\fIovector\fP,"
+.B "     int \fIstringcount\fP, const char *\fIstringname\fP,"
+.B "     const char **\fIstringptr\fP);"
+.sp
+.B int pcre_get_stringnumber(const pcre *\fIcode\fP,
+.B "     const char *\fIname\fP);"
+.sp
+.B int pcre_get_stringtable_entries(const pcre *\fIcode\fP,
+.B "     const char *\fIname\fP, char **\fIfirst\fP, char **\fIlast\fP);"
+.sp
+.B int pcre_get_substring(const char *\fIsubject\fP, int *\fIovector\fP,
+.B "     int \fIstringcount\fP, int \fIstringnumber\fP,"
+.B "     const char **\fIstringptr\fP);"
+.sp
+.B int pcre_get_substring_list(const char *\fIsubject\fP,
+.B "     int *\fIovector\fP, int \fIstringcount\fP, const char ***\fIlistptr\fP);"
+.sp
+.B void pcre_free_substring(const char *\fIstringptr\fP);
+.sp
+.B void pcre_free_substring_list(const char **\fIstringptr\fP);
+.fi
+.
+.
+.SH "PCRE NATIVE API AUXILIARY FUNCTIONS"
+.rs
+.sp
+.nf
+.B int pcre_jit_exec(const pcre *\fIcode\fP, "const pcre_extra *\fIextra\fP,"
+.B "     const char *\fIsubject\fP, int \fIlength\fP, int \fIstartoffset\fP,"
+.B "     int \fIoptions\fP, int *\fIovector\fP, int \fIovecsize\fP,"
+.B "     pcre_jit_stack *\fIjstack\fP);"
+.sp
+.B pcre_jit_stack *pcre_jit_stack_alloc(int \fIstartsize\fP, int \fImaxsize\fP);
+.sp
+.B void pcre_jit_stack_free(pcre_jit_stack *\fIstack\fP);
+.sp
+.B void pcre_assign_jit_stack(pcre_extra *\fIextra\fP,
+.B "     pcre_jit_callback \fIcallback\fP, void *\fIdata\fP);"
+.sp
+.B const unsigned char *pcre_maketables(void);
+.sp
+.B int pcre_fullinfo(const pcre *\fIcode\fP, "const pcre_extra *\fIextra\fP,"
+.B "     int \fIwhat\fP, void *\fIwhere\fP);"
+.sp
+.B int pcre_refcount(pcre *\fIcode\fP, int \fIadjust\fP);
+.sp
+.B int pcre_config(int \fIwhat\fP, void *\fIwhere\fP);
+.sp
+.B const char *pcre_version(void);
+.sp
+.B int pcre_pattern_to_host_byte_order(pcre *\fIcode\fP,
+.B "     pcre_extra *\fIextra\fP, const unsigned char *\fItables\fP);"
+.fi
+.
+.
+.SH "PCRE NATIVE API INDIRECTED FUNCTIONS"
+.rs
+.sp
+.nf
+.B void *(*pcre_malloc)(size_t);
+.sp
+.B void (*pcre_free)(void *);
+.sp
+.B void *(*pcre_stack_malloc)(size_t);
+.sp
+.B void (*pcre_stack_free)(void *);
+.sp
+.B int (*pcre_callout)(pcre_callout_block *);
+.sp
+.B int (*pcre_stack_guard)(void);
+.fi
+.
+.
+.SH "PCRE 8-BIT, 16-BIT, AND 32-BIT LIBRARIES"
+.rs
+.sp
+As well as support for 8-bit character strings, PCRE also supports 16-bit
+strings (from release 8.30) and 32-bit strings (from release 8.32), by means of
+two additional libraries. They can be built as well as, or instead of, the
+8-bit library. To avoid too much complication, this document describes the
+8-bit versions of the functions, with only occasional references to the 16-bit
+and 32-bit libraries.
+.P
+The 16-bit and 32-bit functions operate in the same way as their 8-bit
+counterparts; they just use different data types for their arguments and
+results, and their names start with \fBpcre16_\fP or \fBpcre32_\fP instead of
+\fBpcre_\fP. For every option that has UTF8 in its name (for example,
+PCRE_UTF8), there are corresponding 16-bit and 32-bit names with UTF8 replaced
+by UTF16 or UTF32, respectively. This facility is in fact just cosmetic; the
+16-bit and 32-bit option names define the same bit values.
+.P
+References to bytes and UTF-8 in this document should be read as references to
+16-bit data units and UTF-16 when using the 16-bit library, or 32-bit data
+units and UTF-32 when using the 32-bit library, unless specified otherwise.
+More details of the specific differences for the 16-bit and 32-bit libraries
+are given in the
+.\" HREF
+\fBpcre16\fP
+.\"
+and
+.\" HREF
+\fBpcre32\fP
+.\"
+pages.
+.
+.
+.SH "PCRE API OVERVIEW"
+.rs
+.sp
+PCRE has its own native API, which is described in this document. There are
+also some wrapper functions (for the 8-bit library only) that correspond to the
+POSIX regular expression API, but they do not give access to all the
+functionality. They are described in the
+.\" HREF
+\fBpcreposix\fP
+.\"
+documentation. Both of these APIs define a set of C function calls. A C++
+wrapper (again for the 8-bit library only) is also distributed with PCRE. It is
+documented in the
+.\" HREF
+\fBpcrecpp\fP
+.\"
+page.
+.P
+The native API C function prototypes are defined in the header file
+\fBpcre.h\fP, and on Unix-like systems the (8-bit) library itself is called
+\fBlibpcre\fP. It can normally be accessed by adding \fB-lpcre\fP to the
+command for linking an application that uses PCRE. The header file defines the
+macros PCRE_MAJOR and PCRE_MINOR to contain the major and minor release numbers
+for the library. Applications can use these to include support for different
+releases of PCRE.
+.P
+In a Windows environment, if you want to statically link an application program
+against a non-dll \fBpcre.a\fP file, you must define PCRE_STATIC before
+including \fBpcre.h\fP or \fBpcrecpp.h\fP, because otherwise the
+\fBpcre_malloc()\fP and \fBpcre_free()\fP exported functions will be declared
+\fB__declspec(dllimport)\fP, with unwanted results.
+.P
+The functions \fBpcre_compile()\fP, \fBpcre_compile2()\fP, \fBpcre_study()\fP,
+and \fBpcre_exec()\fP are used for compiling and matching regular expressions
+in a Perl-compatible manner. A sample program that demonstrates the simplest
+way of using them is provided in the file called \fIpcredemo.c\fP in the PCRE
+source distribution. A listing of this program is given in the
+.\" HREF
+\fBpcredemo\fP
+.\"
+documentation, and the
+.\" HREF
+\fBpcresample\fP
+.\"
+documentation describes how to compile and run it.
+.P
+Just-in-time compiler support is an optional feature of PCRE that can be built
+in appropriate hardware environments. It greatly speeds up the matching
+performance of many patterns. Simple programs can easily request that it be
+used if available, by setting an option that is ignored when it is not
+relevant. More complicated programs might need to make use of the functions
+\fBpcre_jit_stack_alloc()\fP, \fBpcre_jit_stack_free()\fP, and
+\fBpcre_assign_jit_stack()\fP in order to control the JIT code's memory usage.
+.P
+From release 8.32 there is also a direct interface for JIT execution, which
+gives improved performance. The JIT-specific functions are discussed in the
+.\" HREF
+\fBpcrejit\fP
+.\"
+documentation.
+.P
+A second matching function, \fBpcre_dfa_exec()\fP, which is not
+Perl-compatible, is also provided. This uses a different algorithm for the
+matching. The alternative algorithm finds all possible matches (at a given
+point in the subject), and scans the subject just once (unless there are
+lookbehind assertions). However, this algorithm does not return captured
+substrings. A description of the two matching algorithms and their advantages
+and disadvantages is given in the
+.\" HREF
+\fBpcrematching\fP
+.\"
+documentation.
+.P
+In addition to the main compiling and matching functions, there are convenience
+functions for extracting captured substrings from a subject string that is
+matched by \fBpcre_exec()\fP. They are:
+.sp
+  \fBpcre_copy_substring()\fP
+  \fBpcre_copy_named_substring()\fP
+  \fBpcre_get_substring()\fP
+  \fBpcre_get_named_substring()\fP
+  \fBpcre_get_substring_list()\fP
+  \fBpcre_get_stringnumber()\fP
+  \fBpcre_get_stringtable_entries()\fP
+.sp
+\fBpcre_free_substring()\fP and \fBpcre_free_substring_list()\fP are also
+provided, to free the memory used for extracted strings.
+.P
+The function \fBpcre_maketables()\fP is used to build a set of character tables
+in the current locale for passing to \fBpcre_compile()\fP, \fBpcre_exec()\fP,
+or \fBpcre_dfa_exec()\fP. This is an optional facility that is provided for
+specialist use. Most commonly, no special tables are passed, in which case
+internal tables that are generated when PCRE is built are used.
+.P
+The function \fBpcre_fullinfo()\fP is used to find out information about a
+compiled pattern. The function \fBpcre_version()\fP returns a pointer to a
+string containing the version of PCRE and its date of release.
+.P
+The function \fBpcre_refcount()\fP maintains a reference count in a data block
+containing a compiled pattern. This is provided for the benefit of
+object-oriented applications.
+.P
+The global variables \fBpcre_malloc\fP and \fBpcre_free\fP initially contain
+the entry points of the standard \fBmalloc()\fP and \fBfree()\fP functions,
+respectively. PCRE calls the memory management functions via these variables,
+so a calling program can replace them if it wishes to intercept the calls. This
+should be done before calling any PCRE functions.
+.P
+The global variables \fBpcre_stack_malloc\fP and \fBpcre_stack_free\fP are also
+indirections to memory management functions. These special functions are used
+only when PCRE is compiled to use the heap for remembering data, instead of
+recursive function calls, when running the \fBpcre_exec()\fP function. See the
+.\" HREF
+\fBpcrebuild\fP
+.\"
+documentation for details of how to do this. It is a non-standard way of
+building PCRE, for use in environments that have limited stacks. Because of the
+greater use of memory management, it runs more slowly. Separate functions are
+provided so that special-purpose external code can be used for this case. When
+used, these functions are always called in a stack-like manner (last obtained,
+first freed), and always for memory blocks of the same size. There is a
+discussion about PCRE's stack usage in the
+.\" HREF
+\fBpcrestack\fP
+.\"
+documentation.
+.P
+The global variable \fBpcre_callout\fP initially contains NULL. It can be set
+by the caller to a "callout" function, which PCRE will then call at specified
+points during a matching operation. Details are given in the
+.\" HREF
+\fBpcrecallout\fP
+.\"
+documentation.
+.P
+The global variable \fBpcre_stack_guard\fP initially contains NULL. It can be
+set by the caller to a function that is called by PCRE whenever it starts
+to compile a parenthesized part of a pattern. When parentheses are nested, PCRE
+uses recursive function calls, which use up the system stack. This function is
+provided so that applications with restricted stacks can force a compilation
+error if the stack runs out. The function should return zero if all is well, or
+non-zero to force an error.
+.
+.
+.\" HTML <a name="newlines"></a>
+.SH NEWLINES
+.rs
+.sp
+PCRE supports five different conventions for indicating line breaks in
+strings: a single CR (carriage return) character, a single LF (linefeed)
+character, the two-character sequence CRLF, any of the three preceding, or any
+Unicode newline sequence. The Unicode newline sequences are the three just
+mentioned, plus the single characters VT (vertical tab, U+000B), FF (form feed,
+U+000C), NEL (next line, U+0085), LS (line separator, U+2028), and PS
+(paragraph separator, U+2029).
+.P
+Each of the first three conventions is used by at least one operating system as
+its standard newline sequence. When PCRE is built, a default can be specified.
+The default default is LF, which is the Unix standard. When PCRE is run, the
+default can be overridden, either when a pattern is compiled, or when it is
+matched.
+.P
+At compile time, the newline convention can be specified by the \fIoptions\fP
+argument of \fBpcre_compile()\fP, or it can be specified by special text at the
+start of the pattern itself; this overrides any other settings. See the
+.\" HREF
+\fBpcrepattern\fP
+.\"
+page for details of the special character sequences.
+.P
+In the PCRE documentation the word "newline" is used to mean "the character or
+pair of characters that indicate a line break". The choice of newline
+convention affects the handling of the dot, circumflex, and dollar
+metacharacters, the handling of #-comments in /x mode, and, when CRLF is a
+recognized line ending sequence, the match position advancement for a
+non-anchored pattern. There is more detail about this in the
+.\" HTML <a href="#execoptions">
+.\" </a>
+section on \fBpcre_exec()\fP options
+.\"
+below.
+.P
+The choice of newline convention does not affect the interpretation of
+the \en or \er escape sequences, nor does it affect what \eR matches, which is
+controlled in a similar way, but by separate options.
+.
+.
+.SH MULTITHREADING
+.rs
+.sp
+The PCRE functions can be used in multi-threading applications, with the
+proviso that the memory management functions pointed to by \fBpcre_malloc\fP,
+\fBpcre_free\fP, \fBpcre_stack_malloc\fP, and \fBpcre_stack_free\fP, and the
+callout and stack-checking functions pointed to by \fBpcre_callout\fP and
+\fBpcre_stack_guard\fP, are shared by all threads.
+.P
+The compiled form of a regular expression is not altered during matching, so
+the same compiled pattern can safely be used by several threads at once.
+.P
+If the just-in-time optimization feature is being used, it needs separate
+memory stack areas for each thread. See the
+.\" HREF
+\fBpcrejit\fP
+.\"
+documentation for more details.
+.
+.
+.SH "SAVING PRECOMPILED PATTERNS FOR LATER USE"
+.rs
+.sp
+The compiled form of a regular expression can be saved and re-used at a later
+time, possibly by a different program, and even on a host other than the one on
+which it was compiled. Details are given in the
+.\" HREF
+\fBpcreprecompile\fP
+.\"
+documentation, which includes a description of the
+\fBpcre_pattern_to_host_byte_order()\fP function. However, compiling a regular
+expression with one version of PCRE for use with a different version is not
+guaranteed to work and may cause crashes.
+.
+.
+.SH "CHECKING BUILD-TIME OPTIONS"
+.rs
+.sp
+.B int pcre_config(int \fIwhat\fP, void *\fIwhere\fP);
+.PP
+The function \fBpcre_config()\fP makes it possible for a PCRE client to
+discover which optional features have been compiled into the PCRE library. The
+.\" HREF
+\fBpcrebuild\fP
+.\"
+documentation has more details about these optional features.
+.P
+The first argument for \fBpcre_config()\fP is an integer, specifying which
+information is required; the second argument is a pointer to a variable into
+which the information is placed. The returned value is zero on success, or the
+negative error code PCRE_ERROR_BADOPTION if the value in the first argument is
+not recognized. The following information is available:
+.sp
+  PCRE_CONFIG_UTF8
+.sp
+The output is an integer that is set to one if UTF-8 support is available;
+otherwise it is set to zero. This value should normally be given to the 8-bit
+version of this function, \fBpcre_config()\fP. If it is given to the 16-bit
+or 32-bit version of this function, the result is PCRE_ERROR_BADOPTION.
+.sp
+  PCRE_CONFIG_UTF16
+.sp
+The output is an integer that is set to one if UTF-16 support is available;
+otherwise it is set to zero. This value should normally be given to the 16-bit
+version of this function, \fBpcre16_config()\fP. If it is given to the 8-bit
+or 32-bit version of this function, the result is PCRE_ERROR_BADOPTION.
+.sp
+  PCRE_CONFIG_UTF32
+.sp
+The output is an integer that is set to one if UTF-32 support is available;
+otherwise it is set to zero. This value should normally be given to the 32-bit
+version of this function, \fBpcre32_config()\fP. If it is given to the 8-bit
+or 16-bit version of this function, the result is PCRE_ERROR_BADOPTION.
+.sp
+  PCRE_CONFIG_UNICODE_PROPERTIES
+.sp
+The output is an integer that is set to one if support for Unicode character
+properties is available; otherwise it is set to zero.
+.sp
+  PCRE_CONFIG_JIT
+.sp
+The output is an integer that is set to one if support for just-in-time
+compiling is available; otherwise it is set to zero.
+.sp
+  PCRE_CONFIG_JITTARGET
+.sp
+The output is a pointer to a zero-terminated "const char *" string. If JIT
+support is available, the string contains the name of the architecture for
+which the JIT compiler is configured, for example "x86 32bit (little endian +
+unaligned)". If JIT support is not available, the result is NULL.
+.sp
+  PCRE_CONFIG_NEWLINE
+.sp
+The output is an integer whose value specifies the default character sequence
+that is recognized as meaning "newline". The values that are supported in
+ASCII/Unicode environments are: 10 for LF, 13 for CR, 3338 for CRLF, -2 for
+ANYCRLF, and -1 for ANY. In EBCDIC environments, CR, ANYCRLF, and ANY yield the
+same values. However, the value for LF is normally 21, though some EBCDIC
+environments use 37. The corresponding values for CRLF are 3349 and 3365. The
+default should normally correspond to the standard sequence for your operating
+system.
+.sp
+  PCRE_CONFIG_BSR
+.sp
+The output is an integer whose value indicates what character sequences the \eR
+escape sequence matches by default. A value of 0 means that \eR matches any
+Unicode line ending sequence; a value of 1 means that \eR matches only CR, LF,
+or CRLF. The default can be overridden when a pattern is compiled or matched.
+.sp
+  PCRE_CONFIG_LINK_SIZE
+.sp
+The output is an integer that contains the number of bytes used for internal
+linkage in compiled regular expressions. For the 8-bit library, the value can
+be 2, 3, or 4. For the 16-bit library, the value is either 2 or 4 and is still
+a number of bytes. For the 32-bit library, the value is either 2 or 4 and is
+still a number of bytes. The default value of 2 is sufficient for all but the
+most massive patterns, since it allows the compiled pattern to be up to 64K in
+size. Larger values allow larger regular expressions to be compiled, at the
+expense of slower matching.
+.sp
+  PCRE_CONFIG_POSIX_MALLOC_THRESHOLD
+.sp
+The output is an integer that contains the threshold above which the POSIX
+interface uses \fBmalloc()\fP for output vectors. Further details are given in
+the
+.\" HREF
+\fBpcreposix\fP
+.\"
+documentation.
+.sp
+  PCRE_CONFIG_PARENS_LIMIT
+.sp
+The output is a long integer that gives the maximum depth of nesting of
+parentheses (of any kind) in a pattern. This limit is imposed to cap the amount
+of system stack used when a pattern is compiled. It is specified when PCRE is
+built; the default is 250. This limit does not take into account the stack that
+may already be used by the calling application. For finer control over
+compilation stack usage, you can set a pointer to an external checking function
+in \fBpcre_stack_guard\fP.
+.sp
+  PCRE_CONFIG_MATCH_LIMIT
+.sp
+The output is a long integer that gives the default limit for the number of
+internal matching function calls in a \fBpcre_exec()\fP execution. Further
+details are given with \fBpcre_exec()\fP below.
+.sp
+  PCRE_CONFIG_MATCH_LIMIT_RECURSION
+.sp
+The output is a long integer that gives the default limit for the depth of
+recursion when calling the internal matching function in a \fBpcre_exec()\fP
+execution. Further details are given with \fBpcre_exec()\fP below.
+.sp
+  PCRE_CONFIG_STACKRECURSE
+.sp
+The output is an integer that is set to one if internal recursion when running
+\fBpcre_exec()\fP is implemented by recursive function calls that use the stack
+to remember their state. This is the usual way that PCRE is compiled. The
+output is zero if PCRE was compiled to use blocks of data on the heap instead
+of recursive function calls. In this case, \fBpcre_stack_malloc\fP and
+\fBpcre_stack_free\fP are called to manage memory blocks on the heap, thus
+avoiding the use of the stack.
+.
+.
+.SH "COMPILING A PATTERN"
+.rs
+.sp
+.nf
+.B pcre *pcre_compile(const char *\fIpattern\fP, int \fIoptions\fP,
+.B "     const char **\fIerrptr\fP, int *\fIerroffset\fP,"
+.B "     const unsigned char *\fItableptr\fP);"
+.sp
+.B pcre *pcre_compile2(const char *\fIpattern\fP, int \fIoptions\fP,
+.B "     int *\fIerrorcodeptr\fP,"
+.B "     const char **\fIerrptr\fP, int *\fIerroffset\fP,"
+.B "     const unsigned char *\fItableptr\fP);"
+.fi
+.P
+Either of the functions \fBpcre_compile()\fP or \fBpcre_compile2()\fP can be
+called to compile a pattern into an internal form. The only difference between
+the two interfaces is that \fBpcre_compile2()\fP has an additional argument,
+\fIerrorcodeptr\fP, via which a numerical error code can be returned. To avoid
+too much repetition, we refer just to \fBpcre_compile()\fP below, but the
+information applies equally to \fBpcre_compile2()\fP.
+.P
+The pattern is a C string terminated by a binary zero, and is passed in the
+\fIpattern\fP argument. A pointer to a single block of memory that is obtained
+via \fBpcre_malloc\fP is returned. This contains the compiled code and related
+data. The \fBpcre\fP type is defined for the returned block; this is a typedef
+for a structure whose contents are not externally defined. It is up to the
+caller to free the memory (via \fBpcre_free\fP) when it is no longer required.
+.P
+Although the compiled code of a PCRE regex is relocatable, that is, it does not
+depend on memory location, the complete \fBpcre\fP data block is not
+fully relocatable, because it may contain a copy of the \fItableptr\fP
+argument, which is an address (see below).
+.P
+The \fIoptions\fP argument contains various bit settings that affect the
+compilation. It should be zero if no options are required. The available
+options are described below. Some of them (in particular, those that are
+compatible with Perl, but some others as well) can also be set and unset from
+within the pattern (see the detailed description in the
+.\" HREF
+\fBpcrepattern\fP
+.\"
+documentation). For those options that can be different in different parts of
+the pattern, the contents of the \fIoptions\fP argument specifies their
+settings at the start of compilation and execution. The PCRE_ANCHORED,
+PCRE_BSR_\fIxxx\fP, PCRE_NEWLINE_\fIxxx\fP, PCRE_NO_UTF8_CHECK, and
+PCRE_NO_START_OPTIMIZE options can be set at the time of matching as well as at
+compile time.
+.P
+If \fIerrptr\fP is NULL, \fBpcre_compile()\fP returns NULL immediately.
+Otherwise, if compilation of a pattern fails, \fBpcre_compile()\fP returns
+NULL, and sets the variable pointed to by \fIerrptr\fP to point to a textual
+error message. This is a static string that is part of the library. You must
+not try to free it. Normally, the offset from the start of the pattern to the
+data unit that was being processed when the error was discovered is placed in
+the variable pointed to by \fIerroffset\fP, which must not be NULL (if it is,
+an immediate error is given). However, for an invalid UTF-8 or UTF-16 string,
+the offset is that of the first data unit of the failing character.
+.P
+Some errors are not detected until the whole pattern has been scanned; in these
+cases, the offset passed back is the length of the pattern. Note that the
+offset is in data units, not characters, even in a UTF mode. It may sometimes
+point into the middle of a UTF-8 or UTF-16 character.
+.P
+If \fBpcre_compile2()\fP is used instead of \fBpcre_compile()\fP, and the
+\fIerrorcodeptr\fP argument is not NULL, a non-zero error code number is
+returned via this argument in the event of an error. This is in addition to the
+textual error message. Error codes and messages are listed below.
+.P
+If the final argument, \fItableptr\fP, is NULL, PCRE uses a default set of
+character tables that are built when PCRE is compiled, using the default C
+locale. Otherwise, \fItableptr\fP must be an address that is the result of a
+call to \fBpcre_maketables()\fP. This value is stored with the compiled
+pattern, and used again by \fBpcre_exec()\fP and \fBpcre_dfa_exec()\fP when the
+pattern is matched. For more discussion, see the section on locale support
+below.
+.P
+This code fragment shows a typical straightforward call to \fBpcre_compile()\fP:
+.sp
+  pcre *re;
+  const char *error;
+  int erroffset;
+  re = pcre_compile(
+    "^A.*Z",          /* the pattern */
+    0,                /* default options */
+    &error,           /* for error message */
+    &erroffset,       /* for error offset */
+    NULL);            /* use default character tables */
+.sp
+The following names for option bits are defined in the \fBpcre.h\fP header
+file:
+.sp
+  PCRE_ANCHORED
+.sp
+If this bit is set, the pattern is forced to be "anchored", that is, it is
+constrained to match only at the first matching point in the string that is
+being searched (the "subject string"). This effect can also be achieved by
+appropriate constructs in the pattern itself, which is the only way to do it in
+Perl.
+.sp
+  PCRE_AUTO_CALLOUT
+.sp
+If this bit is set, \fBpcre_compile()\fP automatically inserts callout items,
+all with number 255, before each pattern item. For discussion of the callout
+facility, see the
+.\" HREF
+\fBpcrecallout\fP
+.\"
+documentation.
+.sp
+  PCRE_BSR_ANYCRLF
+  PCRE_BSR_UNICODE
+.sp
+These options (which are mutually exclusive) control what the \eR escape
+sequence matches. The choice is either to match only CR, LF, or CRLF, or to
+match any Unicode newline sequence. The default is specified when PCRE is
+built. It can be overridden from within the pattern, or by setting an option
+when a compiled pattern is matched.
+.sp
+  PCRE_CASELESS
+.sp
+If this bit is set, letters in the pattern match both upper and lower case
+letters. It is equivalent to Perl's /i option, and it can be changed within a
+pattern by a (?i) option setting. In UTF-8 mode, PCRE always understands the
+concept of case for characters whose values are less than 128, so caseless
+matching is always possible. For characters with higher values, the concept of
+case is supported if PCRE is compiled with Unicode property support, but not
+otherwise. If you want to use caseless matching for characters 128 and above,
+you must ensure that PCRE is compiled with Unicode property support as well as
+with UTF-8 support.
+.sp
+  PCRE_DOLLAR_ENDONLY
+.sp
+If this bit is set, a dollar metacharacter in the pattern matches only at the
+end of the subject string. Without this option, a dollar also matches
+immediately before a newline at the end of the string (but not before any other
+newlines). The PCRE_DOLLAR_ENDONLY option is ignored if PCRE_MULTILINE is set.
+There is no equivalent to this option in Perl, and no way to set it within a
+pattern.
+.sp
+  PCRE_DOTALL
+.sp
+If this bit is set, a dot metacharacter in the pattern matches a character of
+any value, including one that indicates a newline. However, it only ever
+matches one character, even if newlines are coded as CRLF. Without this option,
+a dot does not match when the current position is at a newline. This option is
+equivalent to Perl's /s option, and it can be changed within a pattern by a
+(?s) option setting. A negative class such as [^a] always matches newline
+characters, independent of the setting of this option.
+.sp
+  PCRE_DUPNAMES
+.sp
+If this bit is set, names used to identify capturing subpatterns need not be
+unique. This can be helpful for certain types of pattern when it is known that
+only one instance of the named subpattern can ever be matched. There are more
+details of named subpatterns below; see also the
+.\" HREF
+\fBpcrepattern\fP
+.\"
+documentation.
+.sp
+  PCRE_EXTENDED
+.sp
+If this bit is set, most white space characters in the pattern are totally
+ignored except when escaped or inside a character class. However, white space
+is not allowed within sequences such as (?> that introduce various
+parenthesized subpatterns, nor within a numerical quantifier such as {1,3}.
+However, ignorable white space is permitted between an item and a following
+quantifier and between a quantifier and a following + that indicates
+possessiveness.
+.P
+White space did not used to include the VT character (code 11), because Perl
+did not treat this character as white space. However, Perl changed at release
+5.18, so PCRE followed at release 8.34, and VT is now treated as white space.
+.P
+PCRE_EXTENDED also causes characters between an unescaped # outside a character
+class and the next newline, inclusive, to be ignored. PCRE_EXTENDED is
+equivalent to Perl's /x option, and it can be changed within a pattern by a
+(?x) option setting.
+.P
+Which characters are interpreted as newlines is controlled by the options
+passed to \fBpcre_compile()\fP or by a special sequence at the start of the
+pattern, as described in the section entitled
+.\" HTML <a href="pcrepattern.html#newlines">
+.\" </a>
+"Newline conventions"
+.\"
+in the \fBpcrepattern\fP documentation. Note that the end of this type of
+comment is a literal newline sequence in the pattern; escape sequences that
+happen to represent a newline do not count.
+.P
+This option makes it possible to include comments inside complicated patterns.
+Note, however, that this applies only to data characters. White space characters
+may never appear within special character sequences in a pattern, for example
+within the sequence (?( that introduces a conditional subpattern.
+.sp
+  PCRE_EXTRA
+.sp
+This option was invented in order to turn on additional functionality of PCRE
+that is incompatible with Perl, but it is currently of very little use. When
+set, any backslash in a pattern that is followed by a letter that has no
+special meaning causes an error, thus reserving these combinations for future
+expansion. By default, as in Perl, a backslash followed by a letter with no
+special meaning is treated as a literal. (Perl can, however, be persuaded to
+give an error for this, by running it with the -w option.) There are at present
+no other features controlled by this option. It can also be set by a (?X)
+option setting within a pattern.
+.sp
+  PCRE_FIRSTLINE
+.sp
+If this option is set, an unanchored pattern is required to match before or at
+the first newline in the subject string, though the matched text may continue
+over the newline.
+.sp
+  PCRE_JAVASCRIPT_COMPAT
+.sp
+If this option is set, PCRE's behaviour is changed in some ways so that it is
+compatible with JavaScript rather than Perl. The changes are as follows:
+.P
+(1) A lone closing square bracket in a pattern causes a compile-time error,
+because this is illegal in JavaScript (by default it is treated as a data
+character). Thus, the pattern AB]CD becomes illegal when this option is set.
+.P
+(2) At run time, a back reference to an unset subpattern group matches an empty
+string (by default this causes the current matching alternative to fail). A
+pattern such as (\e1)(a) succeeds when this option is set (assuming it can find
+an "a" in the subject), whereas it fails by default, for Perl compatibility.
+.P
+(3) \eU matches an upper case "U" character; by default \eU causes a compile
+time error (Perl uses \eU to upper case subsequent characters).
+.P
+(4) \eu matches a lower case "u" character unless it is followed by four
+hexadecimal digits, in which case the hexadecimal number defines the code point
+to match. By default, \eu causes a compile time error (Perl uses it to upper
+case the following character).
+.P
+(5) \ex matches a lower case "x" character unless it is followed by two
+hexadecimal digits, in which case the hexadecimal number defines the code point
+to match. By default, as in Perl, a hexadecimal number is always expected after
+\ex, but it may have zero, one, or two digits (so, for example, \exz matches a
+binary zero character followed by z).
+.sp
+  PCRE_MULTILINE
+.sp
+By default, for the purposes of matching "start of line" and "end of line",
+PCRE treats the subject string as consisting of a single line of characters,
+even if it actually contains newlines. The "start of line" metacharacter (^)
+matches only at the start of the string, and the "end of line" metacharacter
+($) matches only at the end of the string, or before a terminating newline
+(except when PCRE_DOLLAR_ENDONLY is set). Note, however, that unless
+PCRE_DOTALL is set, the "any character" metacharacter (.) does not match at a
+newline. This behaviour (for ^, $, and dot) is the same as Perl.
+.P
+When PCRE_MULTILINE it is set, the "start of line" and "end of line" constructs
+match immediately following or immediately before internal newlines in the
+subject string, respectively, as well as at the very start and end. This is
+equivalent to Perl's /m option, and it can be changed within a pattern by a
+(?m) option setting. If there are no newlines in a subject string, or no
+occurrences of ^ or $ in a pattern, setting PCRE_MULTILINE has no effect.
+.sp
+  PCRE_NEVER_UTF
+.sp
+This option locks out interpretation of the pattern as UTF-8 (or UTF-16 or
+UTF-32 in the 16-bit and 32-bit libraries). In particular, it prevents the
+creator of the pattern from switching to UTF interpretation by starting the
+pattern with (*UTF). This may be useful in applications that process patterns
+from external sources. The combination of PCRE_UTF8 and PCRE_NEVER_UTF also
+causes an error.
+.sp
+  PCRE_NEWLINE_CR
+  PCRE_NEWLINE_LF
+  PCRE_NEWLINE_CRLF
+  PCRE_NEWLINE_ANYCRLF
+  PCRE_NEWLINE_ANY
+.sp
+These options override the default newline definition that was chosen when PCRE
+was built. Setting the first or the second specifies that a newline is
+indicated by a single character (CR or LF, respectively). Setting
+PCRE_NEWLINE_CRLF specifies that a newline is indicated by the two-character
+CRLF sequence. Setting PCRE_NEWLINE_ANYCRLF specifies that any of the three
+preceding sequences should be recognized. Setting PCRE_NEWLINE_ANY specifies
+that any Unicode newline sequence should be recognized.
+.P
+In an ASCII/Unicode environment, the Unicode newline sequences are the three
+just mentioned, plus the single characters VT (vertical tab, U+000B), FF (form
+feed, U+000C), NEL (next line, U+0085), LS (line separator, U+2028), and PS
+(paragraph separator, U+2029). For the 8-bit library, the last two are
+recognized only in UTF-8 mode.
+.P
+When PCRE is compiled to run in an EBCDIC (mainframe) environment, the code for
+CR is 0x0d, the same as ASCII. However, the character code for LF is normally
+0x15, though in some EBCDIC environments 0x25 is used. Whichever of these is
+not LF is made to correspond to Unicode's NEL character. EBCDIC codes are all
+less than 256. For more details, see the
+.\" HREF
+\fBpcrebuild\fP
+.\"
+documentation.
+.P
+The newline setting in the options word uses three bits that are treated
+as a number, giving eight possibilities. Currently only six are used (default
+plus the five values above). This means that if you set more than one newline
+option, the combination may or may not be sensible. For example,
+PCRE_NEWLINE_CR with PCRE_NEWLINE_LF is equivalent to PCRE_NEWLINE_CRLF, but
+other combinations may yield unused numbers and cause an error.
+.P
+The only time that a line break in a pattern is specially recognized when
+compiling is when PCRE_EXTENDED is set. CR and LF are white space characters,
+and so are ignored in this mode. Also, an unescaped # outside a character class
+indicates a comment that lasts until after the next line break sequence. In
+other circumstances, line break sequences in patterns are treated as literal
+data.
+.P
+The newline option that is set at compile time becomes the default that is used
+for \fBpcre_exec()\fP and \fBpcre_dfa_exec()\fP, but it can be overridden.
+.sp
+  PCRE_NO_AUTO_CAPTURE
+.sp
+If this option is set, it disables the use of numbered capturing parentheses in
+the pattern. Any opening parenthesis that is not followed by ? behaves as if it
+were followed by ?: but named parentheses can still be used for capturing (and
+they acquire numbers in the usual way). There is no equivalent of this option
+in Perl.
+.sp
+  PCRE_NO_AUTO_POSSESS
+.sp
+If this option is set, it disables "auto-possessification". This is an
+optimization that, for example, turns a+b into a++b in order to avoid
+backtracks into a+ that can never be successful. However, if callouts are in
+use, auto-possessification means that some of them are never taken. You can set
+this option if you want the matching functions to do a full unoptimized search
+and run all the callouts, but it is mainly provided for testing purposes.
+.sp
+  PCRE_NO_START_OPTIMIZE
+.sp
+This is an option that acts at matching time; that is, it is really an option
+for \fBpcre_exec()\fP or \fBpcre_dfa_exec()\fP. If it is set at compile time,
+it is remembered with the compiled pattern and assumed at matching time. This
+is necessary if you want to use JIT execution, because the JIT compiler needs
+to know whether or not this option is set. For details see the discussion of
+PCRE_NO_START_OPTIMIZE
+.\" HTML <a href="#execoptions">
+.\" </a>
+below.
+.\"
+.sp
+  PCRE_UCP
+.sp
+This option changes the way PCRE processes \eB, \eb, \eD, \ed, \eS, \es, \eW,
+\ew, and some of the POSIX character classes. By default, only ASCII characters
+are recognized, but if PCRE_UCP is set, Unicode properties are used instead to
+classify characters. More details are given in the section on
+.\" HTML <a href="pcre.html#genericchartypes">
+.\" </a>
+generic character types
+.\"
+in the
+.\" HREF
+\fBpcrepattern\fP
+.\"
+page. If you set PCRE_UCP, matching one of the items it affects takes much
+longer. The option is available only if PCRE has been compiled with Unicode
+property support.
+.sp
+  PCRE_UNGREEDY
+.sp
+This option inverts the "greediness" of the quantifiers so that they are not
+greedy by default, but become greedy if followed by "?". It is not compatible
+with Perl. It can also be set by a (?U) option setting within the pattern.
+.sp
+  PCRE_UTF8
+.sp
+This option causes PCRE to regard both the pattern and the subject as strings
+of UTF-8 characters instead of single-byte strings. However, it is available
+only when PCRE is built to include UTF support. If not, the use of this option
+provokes an error. Details of how this option changes the behaviour of PCRE are
+given in the
+.\" HREF
+\fBpcreunicode\fP
+.\"
+page.
+.sp
+  PCRE_NO_UTF8_CHECK
+.sp
+When PCRE_UTF8 is set, the validity of the pattern as a UTF-8 string is
+automatically checked. There is a discussion about the
+.\" HTML <a href="pcreunicode.html#utf8strings">
+.\" </a>
+validity of UTF-8 strings
+.\"
+in the
+.\" HREF
+\fBpcreunicode\fP
+.\"
+page. If an invalid UTF-8 sequence is found, \fBpcre_compile()\fP returns an
+error. If you already know that your pattern is valid, and you want to skip
+this check for performance reasons, you can set the PCRE_NO_UTF8_CHECK option.
+When it is set, the effect of passing an invalid UTF-8 string as a pattern is
+undefined. It may cause your program to crash or loop. Note that this option
+can also be passed to \fBpcre_exec()\fP and \fBpcre_dfa_exec()\fP, to suppress
+the validity checking of subject strings only. If the same string is being
+matched many times, the option can be safely set for the second and subsequent
+matchings to improve performance.
+.
+.
+.SH "COMPILATION ERROR CODES"
+.rs
+.sp
+The following table lists the error codes than may be returned by
+\fBpcre_compile2()\fP, along with the error messages that may be returned by
+both compiling functions. Note that error messages are always 8-bit ASCII
+strings, even in 16-bit or 32-bit mode. As PCRE has developed, some error codes
+have fallen out of use. To avoid confusion, they have not been re-used.
+.sp
+   0  no error
+   1  \e at end of pattern
+   2  \ec at end of pattern
+   3  unrecognized character follows \e
+   4  numbers out of order in {} quantifier
+   5  number too big in {} quantifier
+   6  missing terminating ] for character class
+   7  invalid escape sequence in character class
+   8  range out of order in character class
+   9  nothing to repeat
+  10  [this code is not in use]
+  11  internal error: unexpected repeat
+  12  unrecognized character after (? or (?-
+  13  POSIX named classes are supported only within a class
+  14  missing )
+  15  reference to non-existent subpattern
+  16  erroffset passed as NULL
+  17  unknown option bit(s) set
+  18  missing ) after comment
+  19  [this code is not in use]
+  20  regular expression is too large
+  21  failed to get memory
+  22  unmatched parentheses
+  23  internal error: code overflow
+  24  unrecognized character after (?<
+  25  lookbehind assertion is not fixed length
+  26  malformed number or name after (?(
+  27  conditional group contains more than two branches
+  28  assertion expected after (?(
+  29  (?R or (?[+-]digits must be followed by )
+  30  unknown POSIX class name
+  31  POSIX collating elements are not supported
+  32  this version of PCRE is compiled without UTF support
+  33  [this code is not in use]
+  34  character value in \ex{} or \eo{} is too large
+  35  invalid condition (?(0)
+  36  \eC not allowed in lookbehind assertion
+  37  PCRE does not support \eL, \el, \eN{name}, \eU, or \eu
+  38  number after (?C is > 255
+  39  closing ) for (?C expected
+  40  recursive call could loop indefinitely
+  41  unrecognized character after (?P
+  42  syntax error in subpattern name (missing terminator)
+  43  two named subpatterns have the same name
+  44  invalid UTF-8 string (specifically UTF-8)
+  45  support for \eP, \ep, and \eX has not been compiled
+  46  malformed \eP or \ep sequence
+  47  unknown property name after \eP or \ep
+  48  subpattern name is too long (maximum 32 characters)
+  49  too many named subpatterns (maximum 10000)
+  50  [this code is not in use]
+  51  octal value is greater than \e377 in 8-bit non-UTF-8 mode
+  52  internal error: overran compiling workspace
+  53  internal error: previously-checked referenced subpattern
+        not found
+  54  DEFINE group contains more than one branch
+  55  repeating a DEFINE group is not allowed
+  56  inconsistent NEWLINE options
+  57  \eg is not followed by a braced, angle-bracketed, or quoted
+        name/number or by a plain number
+  58  a numbered reference must not be zero
+  59  an argument is not allowed for (*ACCEPT), (*FAIL), or (*COMMIT)
+  60  (*VERB) not recognized or malformed
+  61  number is too big
+  62  subpattern name expected
+  63  digit expected after (?+
+  64  ] is an invalid data character in JavaScript compatibility mode
+  65  different names for subpatterns of the same number are
+        not allowed
+  66  (*MARK) must have an argument
+  67  this version of PCRE is not compiled with Unicode property
+        support
+  68  \ec must be followed by an ASCII character
+  69  \ek is not followed by a braced, angle-bracketed, or quoted name
+  70  internal error: unknown opcode in find_fixedlength()
+  71  \eN is not supported in a class
+  72  too many forward references
+  73  disallowed Unicode code point (>= 0xd800 && <= 0xdfff)
+  74  invalid UTF-16 string (specifically UTF-16)
+  75  name is too long in (*MARK), (*PRUNE), (*SKIP), or (*THEN)
+  76  character value in \eu.... sequence is too large
+  77  invalid UTF-32 string (specifically UTF-32)
+  78  setting UTF is disabled by the application
+  79  non-hex character in \ex{} (closing brace missing?)
+  80  non-octal character in \eo{} (closing brace missing?)
+  81  missing opening brace after \eo
+  82  parentheses are too deeply nested
+  83  invalid range in character class
+  84  group name must start with a non-digit
+  85  parentheses are too deeply nested (stack check)
+.sp
+The numbers 32 and 10000 in errors 48 and 49 are defaults; different values may
+be used if the limits were changed when PCRE was built.
+.
+.
+.\" HTML <a name="studyingapattern"></a>
+.SH "STUDYING A PATTERN"
+.rs
+.sp
+.nf
+.B pcre_extra *pcre_study(const pcre *\fIcode\fP, int \fIoptions\fP,
+.B "     const char **\fIerrptr\fP);"
+.fi
+.PP
+If a compiled pattern is going to be used several times, it is worth spending
+more time analyzing it in order to speed up the time taken for matching. The
+function \fBpcre_study()\fP takes a pointer to a compiled pattern as its first
+argument. If studying the pattern produces additional information that will
+help speed up matching, \fBpcre_study()\fP returns a pointer to a
+\fBpcre_extra\fP block, in which the \fIstudy_data\fP field points to the
+results of the study.
+.P
+The returned value from \fBpcre_study()\fP can be passed directly to
+\fBpcre_exec()\fP or \fBpcre_dfa_exec()\fP. However, a \fBpcre_extra\fP block
+also contains other fields that can be set by the caller before the block is
+passed; these are described
+.\" HTML <a href="#extradata">
+.\" </a>
+below
+.\"
+in the section on matching a pattern.
+.P
+If studying the pattern does not produce any useful information,
+\fBpcre_study()\fP returns NULL by default. In that circumstance, if the
+calling program wants to pass any of the other fields to \fBpcre_exec()\fP or
+\fBpcre_dfa_exec()\fP, it must set up its own \fBpcre_extra\fP block. However,
+if \fBpcre_study()\fP is called with the PCRE_STUDY_EXTRA_NEEDED option, it
+returns a \fBpcre_extra\fP block even if studying did not find any additional
+information. It may still return NULL, however, if an error occurs in
+\fBpcre_study()\fP.
+.P
+The second argument of \fBpcre_study()\fP contains option bits. There are three
+further options in addition to PCRE_STUDY_EXTRA_NEEDED:
+.sp
+  PCRE_STUDY_JIT_COMPILE
+  PCRE_STUDY_JIT_PARTIAL_HARD_COMPILE
+  PCRE_STUDY_JIT_PARTIAL_SOFT_COMPILE
+.sp
+If any of these are set, and the just-in-time compiler is available, the
+pattern is further compiled into machine code that executes much faster than
+the \fBpcre_exec()\fP interpretive matching function. If the just-in-time
+compiler is not available, these options are ignored. All undefined bits in the
+\fIoptions\fP argument must be zero.
+.P
+JIT compilation is a heavyweight optimization. It can take some time for
+patterns to be analyzed, and for one-off matches and simple patterns the
+benefit of faster execution might be offset by a much slower study time.
+Not all patterns can be optimized by the JIT compiler. For those that cannot be
+handled, matching automatically falls back to the \fBpcre_exec()\fP
+interpreter. For more details, see the
+.\" HREF
+\fBpcrejit\fP
+.\"
+documentation.
+.P
+The third argument for \fBpcre_study()\fP is a pointer for an error message. If
+studying succeeds (even if no data is returned), the variable it points to is
+set to NULL. Otherwise it is set to point to a textual error message. This is a
+static string that is part of the library. You must not try to free it. You
+should test the error pointer for NULL after calling \fBpcre_study()\fP, to be
+sure that it has run successfully.
+.P
+When you are finished with a pattern, you can free the memory used for the
+study data by calling \fBpcre_free_study()\fP. This function was added to the
+API for release 8.20. For earlier versions, the memory could be freed with
+\fBpcre_free()\fP, just like the pattern itself. This will still work in cases
+where JIT optimization is not used, but it is advisable to change to the new
+function when convenient.
+.P
+This is a typical way in which \fBpcre_study\fP() is used (except that in a
+real application there should be tests for errors):
+.sp
+  int rc;
+  pcre *re;
+  pcre_extra *sd;
+  re = pcre_compile("pattern", 0, &error, &erroroffset, NULL);
+  sd = pcre_study(
+    re,             /* result of pcre_compile() */
+    0,              /* no options */
+    &error);        /* set to NULL or points to a message */
+  rc = pcre_exec(   /* see below for details of pcre_exec() options */
+    re, sd, "subject", 7, 0, 0, ovector, 30);
+  ...
+  pcre_free_study(sd);
+  pcre_free(re);
+.sp
+Studying a pattern does two things: first, a lower bound for the length of
+subject string that is needed to match the pattern is computed. This does not
+mean that there are any strings of that length that match, but it does
+guarantee that no shorter strings match. The value is used to avoid wasting
+time by trying to match strings that are shorter than the lower bound. You can
+find out the value in a calling program via the \fBpcre_fullinfo()\fP function.
+.P
+Studying a pattern is also useful for non-anchored patterns that do not have a
+single fixed starting character. A bitmap of possible starting bytes is
+created. This speeds up finding a position in the subject at which to start
+matching. (In 16-bit mode, the bitmap is used for 16-bit values less than 256.
+In 32-bit mode, the bitmap is used for 32-bit values less than 256.)
+.P
+These two optimizations apply to both \fBpcre_exec()\fP and
+\fBpcre_dfa_exec()\fP, and the information is also used by the JIT compiler.
+The optimizations can be disabled by setting the PCRE_NO_START_OPTIMIZE option.
+You might want to do this if your pattern contains callouts or (*MARK) and you
+want to make use of these facilities in cases where matching fails.
+.P
+PCRE_NO_START_OPTIMIZE can be specified at either compile time or execution
+time. However, if PCRE_NO_START_OPTIMIZE is passed to \fBpcre_exec()\fP, (that
+is, after any JIT compilation has happened) JIT execution is disabled. For JIT
+execution to work with PCRE_NO_START_OPTIMIZE, the option must be set at
+compile time.
+.P
+There is a longer discussion of PCRE_NO_START_OPTIMIZE
+.\" HTML <a href="#execoptions">
+.\" </a>
+below.
+.\"
+.
+.
+.\" HTML <a name="localesupport"></a>
+.SH "LOCALE SUPPORT"
+.rs
+.sp
+PCRE handles caseless matching, and determines whether characters are letters,
+digits, or whatever, by reference to a set of tables, indexed by character
+code point. When running in UTF-8 mode, or in the 16- or 32-bit libraries, this
+applies only to characters with code points less than 256. By default,
+higher-valued code points never match escapes such as \ew or \ed. However, if
+PCRE is built with Unicode property support, all characters can be tested with
+\ep and \eP, or, alternatively, the PCRE_UCP option can be set when a pattern
+is compiled; this causes \ew and friends to use Unicode property support
+instead of the built-in tables.
+.P
+The use of locales with Unicode is discouraged. If you are handling characters
+with code points greater than 128, you should either use Unicode support, or
+use locales, but not try to mix the two.
+.P
+PCRE contains an internal set of tables that are used when the final argument
+of \fBpcre_compile()\fP is NULL. These are sufficient for many applications.
+Normally, the internal tables recognize only ASCII characters. However, when
+PCRE is built, it is possible to cause the internal tables to be rebuilt in the
+default "C" locale of the local system, which may cause them to be different.
+.P
+The internal tables can always be overridden by tables supplied by the
+application that calls PCRE. These may be created in a different locale from
+the default. As more and more applications change to using Unicode, the need
+for this locale support is expected to die away.
+.P
+External tables are built by calling the \fBpcre_maketables()\fP function,
+which has no arguments, in the relevant locale. The result can then be passed
+to \fBpcre_compile()\fP as often as necessary. For example, to build and use
+tables that are appropriate for the French locale (where accented characters
+with values greater than 128 are treated as letters), the following code could
+be used:
+.sp
+  setlocale(LC_CTYPE, "fr_FR");
+  tables = pcre_maketables();
+  re = pcre_compile(..., tables);
+.sp
+The locale name "fr_FR" is used on Linux and other Unix-like systems; if you
+are using Windows, the name for the French locale is "french".
+.P
+When \fBpcre_maketables()\fP runs, the tables are built in memory that is
+obtained via \fBpcre_malloc\fP. It is the caller's responsibility to ensure
+that the memory containing the tables remains available for as long as it is
+needed.
+.P
+The pointer that is passed to \fBpcre_compile()\fP is saved with the compiled
+pattern, and the same tables are used via this pointer by \fBpcre_study()\fP
+and also by \fBpcre_exec()\fP and \fBpcre_dfa_exec()\fP. Thus, for any single
+pattern, compilation, studying and matching all happen in the same locale, but
+different patterns can be processed in different locales.
+.P
+It is possible to pass a table pointer or NULL (indicating the use of the
+internal tables) to \fBpcre_exec()\fP or \fBpcre_dfa_exec()\fP (see the
+discussion below in the section on matching a pattern). This facility is
+provided for use with pre-compiled patterns that have been saved and reloaded.
+Character tables are not saved with patterns, so if a non-standard table was
+used at compile time, it must be provided again when the reloaded pattern is
+matched. Attempting to use this facility to match a pattern in a different
+locale from the one in which it was compiled is likely to lead to anomalous
+(usually incorrect) results.
+.
+.
+.\" HTML <a name="infoaboutpattern"></a>
+.SH "INFORMATION ABOUT A PATTERN"
+.rs
+.sp
+.nf
+.B int pcre_fullinfo(const pcre *\fIcode\fP, "const pcre_extra *\fIextra\fP,"
+.B "     int \fIwhat\fP, void *\fIwhere\fP);"
+.fi
+.PP
+The \fBpcre_fullinfo()\fP function returns information about a compiled
+pattern. It replaces the \fBpcre_info()\fP function, which was removed from the
+library at version 8.30, after more than 10 years of obsolescence.
+.P
+The first argument for \fBpcre_fullinfo()\fP is a pointer to the compiled
+pattern. The second argument is the result of \fBpcre_study()\fP, or NULL if
+the pattern was not studied. The third argument specifies which piece of
+information is required, and the fourth argument is a pointer to a variable
+to receive the data. The yield of the function is zero for success, or one of
+the following negative numbers:
+.sp
+  PCRE_ERROR_NULL           the argument \fIcode\fP was NULL
+                            the argument \fIwhere\fP was NULL
+  PCRE_ERROR_BADMAGIC       the "magic number" was not found
+  PCRE_ERROR_BADENDIANNESS  the pattern was compiled with different
+                            endianness
+  PCRE_ERROR_BADOPTION      the value of \fIwhat\fP was invalid
+  PCRE_ERROR_UNSET          the requested field is not set
+.sp
+The "magic number" is placed at the start of each compiled pattern as an simple
+check against passing an arbitrary memory pointer. The endianness error can
+occur if a compiled pattern is saved and reloaded on a different host. Here is
+a typical call of \fBpcre_fullinfo()\fP, to obtain the length of the compiled
+pattern:
+.sp
+  int rc;
+  size_t length;
+  rc = pcre_fullinfo(
+    re,               /* result of pcre_compile() */
+    sd,               /* result of pcre_study(), or NULL */
+    PCRE_INFO_SIZE,   /* what is required */
+    &length);         /* where to put the data */
+.sp
+The possible values for the third argument are defined in \fBpcre.h\fP, and are
+as follows:
+.sp
+  PCRE_INFO_BACKREFMAX
+.sp
+Return the number of the highest back reference in the pattern. The fourth
+argument should point to an \fBint\fP variable. Zero is returned if there are
+no back references.
+.sp
+  PCRE_INFO_CAPTURECOUNT
+.sp
+Return the number of capturing subpatterns in the pattern. The fourth argument
+should point to an \fBint\fP variable.
+.sp
+  PCRE_INFO_DEFAULT_TABLES
+.sp
+Return a pointer to the internal default character tables within PCRE. The
+fourth argument should point to an \fBunsigned char *\fP variable. This
+information call is provided for internal use by the \fBpcre_study()\fP
+function. External callers can cause PCRE to use its internal tables by passing
+a NULL table pointer.
+.sp
+  PCRE_INFO_FIRSTBYTE (deprecated)
+.sp
+Return information about the first data unit of any matched string, for a
+non-anchored pattern. The name of this option refers to the 8-bit library,
+where data units are bytes. The fourth argument should point to an \fBint\fP
+variable. Negative values are used for special cases. However, this means that
+when the 32-bit library is in non-UTF-32 mode, the full 32-bit range of
+characters cannot be returned. For this reason, this value is deprecated; use
+PCRE_INFO_FIRSTCHARACTERFLAGS and PCRE_INFO_FIRSTCHARACTER instead.
+.P
+If there is a fixed first value, for example, the letter "c" from a pattern
+such as (cat|cow|coyote), its value is returned. In the 8-bit library, the
+value is always less than 256. In the 16-bit library the value can be up to
+0xffff. In the 32-bit library the value can be up to 0x10ffff.
+.P
+If there is no fixed first value, and if either
+.sp
+(a) the pattern was compiled with the PCRE_MULTILINE option, and every branch
+starts with "^", or
+.sp
+(b) every branch of the pattern starts with ".*" and PCRE_DOTALL is not set
+(if it were set, the pattern would be anchored),
+.sp
+-1 is returned, indicating that the pattern matches only at the start of a
+subject string or after any newline within the string. Otherwise -2 is
+returned. For anchored patterns, -2 is returned.
+.sp
+  PCRE_INFO_FIRSTCHARACTER
+.sp
+Return the value of the first data unit (non-UTF character) of any matched
+string in the situation where PCRE_INFO_FIRSTCHARACTERFLAGS returns 1;
+otherwise return 0. The fourth argument should point to an \fBuint_t\fP
+variable.
+.P
+In the 8-bit library, the value is always less than 256. In the 16-bit library
+the value can be up to 0xffff. In the 32-bit library in UTF-32 mode the value
+can be up to 0x10ffff, and up to 0xffffffff when not using UTF-32 mode.
+.sp
+  PCRE_INFO_FIRSTCHARACTERFLAGS
+.sp
+Return information about the first data unit of any matched string, for a
+non-anchored pattern. The fourth argument should point to an \fBint\fP
+variable.
+.P
+If there is a fixed first value, for example, the letter "c" from a pattern
+such as (cat|cow|coyote), 1 is returned, and the character value can be
+retrieved using PCRE_INFO_FIRSTCHARACTER. If there is no fixed first value, and
+if either
+.sp
+(a) the pattern was compiled with the PCRE_MULTILINE option, and every branch
+starts with "^", or
+.sp
+(b) every branch of the pattern starts with ".*" and PCRE_DOTALL is not set
+(if it were set, the pattern would be anchored),
+.sp
+2 is returned, indicating that the pattern matches only at the start of a
+subject string or after any newline within the string. Otherwise 0 is
+returned. For anchored patterns, 0 is returned.
+.sp
+  PCRE_INFO_FIRSTTABLE
+.sp
+If the pattern was studied, and this resulted in the construction of a 256-bit
+table indicating a fixed set of values for the first data unit in any matching
+string, a pointer to the table is returned. Otherwise NULL is returned. The
+fourth argument should point to an \fBunsigned char *\fP variable.
+.sp
+  PCRE_INFO_HASCRORLF
+.sp
+Return 1 if the pattern contains any explicit matches for CR or LF characters,
+otherwise 0. The fourth argument should point to an \fBint\fP variable. An
+explicit match is either a literal CR or LF character, or \er or \en.
+.sp
+  PCRE_INFO_JCHANGED
+.sp
+Return 1 if the (?J) or (?-J) option setting is used in the pattern, otherwise
+0. The fourth argument should point to an \fBint\fP variable. (?J) and
+(?-J) set and unset the local PCRE_DUPNAMES option, respectively.
+.sp
+  PCRE_INFO_JIT
+.sp
+Return 1 if the pattern was studied with one of the JIT options, and
+just-in-time compiling was successful. The fourth argument should point to an
+\fBint\fP variable. A return value of 0 means that JIT support is not available
+in this version of PCRE, or that the pattern was not studied with a JIT option,
+or that the JIT compiler could not handle this particular pattern. See the
+.\" HREF
+\fBpcrejit\fP
+.\"
+documentation for details of what can and cannot be handled.
+.sp
+  PCRE_INFO_JITSIZE
+.sp
+If the pattern was successfully studied with a JIT option, return the size of
+the JIT compiled code, otherwise return zero. The fourth argument should point
+to a \fBsize_t\fP variable.
+.sp
+  PCRE_INFO_LASTLITERAL
+.sp
+Return the value of the rightmost literal data unit that must exist in any
+matched string, other than at its start, if such a value has been recorded. The
+fourth argument should point to an \fBint\fP variable. If there is no such
+value, -1 is returned. For anchored patterns, a last literal value is recorded
+only if it follows something of variable length. For example, for the pattern
+/^a\ed+z\ed+/ the returned value is "z", but for /^a\edz\ed/ the returned value
+is -1.
+.P
+Since for the 32-bit library using the non-UTF-32 mode, this function is unable
+to return the full 32-bit range of characters, this value is deprecated;
+instead the PCRE_INFO_REQUIREDCHARFLAGS and PCRE_INFO_REQUIREDCHAR values should
+be used.
+.sp
+  PCRE_INFO_MATCH_EMPTY
+.sp
+Return 1 if the pattern can match an empty string, otherwise 0. The fourth
+argument should point to an \fBint\fP variable.
+.sp
+  PCRE_INFO_MATCHLIMIT
+.sp
+If the pattern set a match limit by including an item of the form
+(*LIMIT_MATCH=nnnn) at the start, the value is returned. The fourth argument
+should point to an unsigned 32-bit integer. If no such value has been set, the
+call to \fBpcre_fullinfo()\fP returns the error PCRE_ERROR_UNSET.
+.sp
+  PCRE_INFO_MAXLOOKBEHIND
+.sp
+Return the number of characters (NB not data units) in the longest lookbehind
+assertion in the pattern. This information is useful when doing multi-segment
+matching using the partial matching facilities. Note that the simple assertions
+\eb and \eB require a one-character lookbehind. \eA also registers a
+one-character lookbehind, though it does not actually inspect the previous
+character. This is to ensure that at least one character from the old segment
+is retained when a new segment is processed. Otherwise, if there are no
+lookbehinds in the pattern, \eA might match incorrectly at the start of a new
+segment.
+.sp
+  PCRE_INFO_MINLENGTH
+.sp
+If the pattern was studied and a minimum length for matching subject strings
+was computed, its value is returned. Otherwise the returned value is -1. The
+value is a number of characters, which in UTF mode may be different from the
+number of data units. The fourth argument should point to an \fBint\fP
+variable. A non-negative value is a lower bound to the length of any matching
+string. There may not be any strings of that length that do actually match, but
+every string that does match is at least that long.
+.sp
+  PCRE_INFO_NAMECOUNT
+  PCRE_INFO_NAMEENTRYSIZE
+  PCRE_INFO_NAMETABLE
+.sp
+PCRE supports the use of named as well as numbered capturing parentheses. The
+names are just an additional way of identifying the parentheses, which still
+acquire numbers. Several convenience functions such as
+\fBpcre_get_named_substring()\fP are provided for extracting captured
+substrings by name. It is also possible to extract the data directly, by first
+converting the name to a number in order to access the correct pointers in the
+output vector (described with \fBpcre_exec()\fP below). To do the conversion,
+you need to use the name-to-number map, which is described by these three
+values.
+.P
+The map consists of a number of fixed-size entries. PCRE_INFO_NAMECOUNT gives
+the number of entries, and PCRE_INFO_NAMEENTRYSIZE gives the size of each
+entry; both of these return an \fBint\fP value. The entry size depends on the
+length of the longest name. PCRE_INFO_NAMETABLE returns a pointer to the first
+entry of the table. This is a pointer to \fBchar\fP in the 8-bit library, where
+the first two bytes of each entry are the number of the capturing parenthesis,
+most significant byte first. In the 16-bit library, the pointer points to
+16-bit data units, the first of which contains the parenthesis number. In the
+32-bit library, the pointer points to 32-bit data units, the first of which
+contains the parenthesis number. The rest of the entry is the corresponding
+name, zero terminated.
+.P
+The names are in alphabetical order. If (?| is used to create multiple groups
+with the same number, as described in the
+.\" HTML <a href="pcrepattern.html#dupsubpatternnumber">
+.\" </a>
+section on duplicate subpattern numbers
+.\"
+in the
+.\" HREF
+\fBpcrepattern\fP
+.\"
+page, the groups may be given the same name, but there is only one entry in the
+table. Different names for groups of the same number are not permitted.
+Duplicate names for subpatterns with different numbers are permitted,
+but only if PCRE_DUPNAMES is set. They appear in the table in the order in
+which they were found in the pattern. In the absence of (?| this is the order
+of increasing number; when (?| is used this is not necessarily the case because
+later subpatterns may have lower numbers.
+.P
+As a simple example of the name/number table, consider the following pattern
+after compilation by the 8-bit library (assume PCRE_EXTENDED is set, so white
+space - including newlines - is ignored):
+.sp
+.\" JOIN
+  (?<date> (?<year>(\ed\ed)?\ed\ed) -
+  (?<month>\ed\ed) - (?<day>\ed\ed) )
+.sp
+There are four named subpatterns, so the table has four entries, and each entry
+in the table is eight bytes long. The table is as follows, with non-printing
+bytes shows in hexadecimal, and undefined bytes shown as ??:
+.sp
+  00 01 d  a  t  e  00 ??
+  00 05 d  a  y  00 ?? ??
+  00 04 m  o  n  t  h  00
+  00 02 y  e  a  r  00 ??
+.sp
+When writing code to extract data from named subpatterns using the
+name-to-number map, remember that the length of the entries is likely to be
+different for each compiled pattern.
+.sp
+  PCRE_INFO_OKPARTIAL
+.sp
+Return 1 if the pattern can be used for partial matching with
+\fBpcre_exec()\fP, otherwise 0. The fourth argument should point to an
+\fBint\fP variable. From release 8.00, this always returns 1, because the
+restrictions that previously applied to partial matching have been lifted. The
+.\" HREF
+\fBpcrepartial\fP
+.\"
+documentation gives details of partial matching.
+.sp
+  PCRE_INFO_OPTIONS
+.sp
+Return a copy of the options with which the pattern was compiled. The fourth
+argument should point to an \fBunsigned long int\fP variable. These option bits
+are those specified in the call to \fBpcre_compile()\fP, modified by any
+top-level option settings at the start of the pattern itself. In other words,
+they are the options that will be in force when matching starts. For example,
+if the pattern /(?im)abc(?-i)d/ is compiled with the PCRE_EXTENDED option, the
+result is PCRE_CASELESS, PCRE_MULTILINE, and PCRE_EXTENDED.
+.P
+A pattern is automatically anchored by PCRE if all of its top-level
+alternatives begin with one of the following:
+.sp
+  ^     unless PCRE_MULTILINE is set
+  \eA    always
+  \eG    always
+.\" JOIN
+  .*    if PCRE_DOTALL is set and there are no back
+          references to the subpattern in which .* appears
+.sp
+For such patterns, the PCRE_ANCHORED bit is set in the options returned by
+\fBpcre_fullinfo()\fP.
+.sp
+  PCRE_INFO_RECURSIONLIMIT
+.sp
+If the pattern set a recursion limit by including an item of the form
+(*LIMIT_RECURSION=nnnn) at the start, the value is returned. The fourth
+argument should point to an unsigned 32-bit integer. If no such value has been
+set, the call to \fBpcre_fullinfo()\fP returns the error PCRE_ERROR_UNSET.
+.sp
+  PCRE_INFO_SIZE
+.sp
+Return the size of the compiled pattern in bytes (for all three libraries). The
+fourth argument should point to a \fBsize_t\fP variable. This value does not
+include the size of the \fBpcre\fP structure that is returned by
+\fBpcre_compile()\fP. The value that is passed as the argument to
+\fBpcre_malloc()\fP when \fBpcre_compile()\fP is getting memory in which to
+place the compiled data is the value returned by this option plus the size of
+the \fBpcre\fP structure. Studying a compiled pattern, with or without JIT,
+does not alter the value returned by this option.
+.sp
+  PCRE_INFO_STUDYSIZE
+.sp
+Return the size in bytes (for all three libraries) of the data block pointed to
+by the \fIstudy_data\fP field in a \fBpcre_extra\fP block. If \fBpcre_extra\fP
+is NULL, or there is no study data, zero is returned. The fourth argument
+should point to a \fBsize_t\fP variable. The \fIstudy_data\fP field is set by
+\fBpcre_study()\fP to record information that will speed up matching (see the
+section entitled
+.\" HTML <a href="#studyingapattern">
+.\" </a>
+"Studying a pattern"
+.\"
+above). The format of the \fIstudy_data\fP block is private, but its length
+is made available via this option so that it can be saved and restored (see the
+.\" HREF
+\fBpcreprecompile\fP
+.\"
+documentation for details).
+.sp
+  PCRE_INFO_REQUIREDCHARFLAGS
+.sp
+Returns 1 if there is a rightmost literal data unit that must exist in any
+matched string, other than at its start. The fourth argument should  point to
+an \fBint\fP variable. If there is no such value, 0 is returned. If returning
+1, the character value itself can be retrieved using PCRE_INFO_REQUIREDCHAR.
+.P
+For anchored patterns, a last literal value is recorded only if it follows
+something of variable length. For example, for the pattern /^a\ed+z\ed+/ the
+returned value 1 (with "z" returned from PCRE_INFO_REQUIREDCHAR), but for
+/^a\edz\ed/ the returned value is 0.
+.sp
+  PCRE_INFO_REQUIREDCHAR
+.sp
+Return the value of the rightmost literal data unit that must exist in any
+matched string, other than at its start, if such a value has been recorded. The
+fourth argument should point to an \fBuint32_t\fP variable. If there is no such
+value, 0 is returned.
+.
+.
+.SH "REFERENCE COUNTS"
+.rs
+.sp
+.B int pcre_refcount(pcre *\fIcode\fP, int \fIadjust\fP);
+.PP
+The \fBpcre_refcount()\fP function is used to maintain a reference count in the
+data block that contains a compiled pattern. It is provided for the benefit of
+applications that operate in an object-oriented manner, where different parts
+of the application may be using the same compiled pattern, but you want to free
+the block when they are all done.
+.P
+When a pattern is compiled, the reference count field is initialized to zero.
+It is changed only by calling this function, whose action is to add the
+\fIadjust\fP value (which may be positive or negative) to it. The yield of the
+function is the new value. However, the value of the count is constrained to
+lie between 0 and 65535, inclusive. If the new value is outside these limits,
+it is forced to the appropriate limit value.
+.P
+Except when it is zero, the reference count is not correctly preserved if a
+pattern is compiled on one host and then transferred to a host whose byte-order
+is different. (This seems a highly unlikely scenario.)
+.
+.
+.SH "MATCHING A PATTERN: THE TRADITIONAL FUNCTION"
+.rs
+.sp
+.nf
+.B int pcre_exec(const pcre *\fIcode\fP, "const pcre_extra *\fIextra\fP,"
+.B "     const char *\fIsubject\fP," int \fIlength\fP, int \fIstartoffset\fP,
+.B "     int \fIoptions\fP, int *\fIovector\fP, int \fIovecsize\fP);"
+.fi
+.P
+The function \fBpcre_exec()\fP is called to match a subject string against a
+compiled pattern, which is passed in the \fIcode\fP argument. If the
+pattern was studied, the result of the study should be passed in the
+\fIextra\fP argument. You can call \fBpcre_exec()\fP with the same \fIcode\fP
+and \fIextra\fP arguments as many times as you like, in order to match
+different subject strings with the same pattern.
+.P
+This function is the main matching facility of the library, and it operates in
+a Perl-like manner. For specialist use there is also an alternative matching
+function, which is described
+.\" HTML <a href="#dfamatch">
+.\" </a>
+below
+.\"
+in the section about the \fBpcre_dfa_exec()\fP function.
+.P
+In most applications, the pattern will have been compiled (and optionally
+studied) in the same process that calls \fBpcre_exec()\fP. However, it is
+possible to save compiled patterns and study data, and then use them later
+in different processes, possibly even on different hosts. For a discussion
+about this, see the
+.\" HREF
+\fBpcreprecompile\fP
+.\"
+documentation.
+.P
+Here is an example of a simple call to \fBpcre_exec()\fP:
+.sp
+  int rc;
+  int ovector[30];
+  rc = pcre_exec(
+    re,             /* result of pcre_compile() */
+    NULL,           /* we didn't study the pattern */
+    "some string",  /* the subject string */
+    11,             /* the length of the subject string */
+    0,              /* start at offset 0 in the subject */
+    0,              /* default options */
+    ovector,        /* vector of integers for substring information */
+    30);            /* number of elements (NOT size in bytes) */
+.
+.
+.\" HTML <a name="extradata"></a>
+.SS "Extra data for \fBpcre_exec()\fR"
+.rs
+.sp
+If the \fIextra\fP argument is not NULL, it must point to a \fBpcre_extra\fP
+data block. The \fBpcre_study()\fP function returns such a block (when it
+doesn't return NULL), but you can also create one for yourself, and pass
+additional information in it. The \fBpcre_extra\fP block contains the following
+fields (not necessarily in this order):
+.sp
+  unsigned long int \fIflags\fP;
+  void *\fIstudy_data\fP;
+  void *\fIexecutable_jit\fP;
+  unsigned long int \fImatch_limit\fP;
+  unsigned long int \fImatch_limit_recursion\fP;
+  void *\fIcallout_data\fP;
+  const unsigned char *\fItables\fP;
+  unsigned char **\fImark\fP;
+.sp
+In the 16-bit version of this structure, the \fImark\fP field has type
+"PCRE_UCHAR16 **".
+.sp
+In the 32-bit version of this structure, the \fImark\fP field has type
+"PCRE_UCHAR32 **".
+.P
+The \fIflags\fP field is used to specify which of the other fields are set. The
+flag bits are:
+.sp
+  PCRE_EXTRA_CALLOUT_DATA
+  PCRE_EXTRA_EXECUTABLE_JIT
+  PCRE_EXTRA_MARK
+  PCRE_EXTRA_MATCH_LIMIT
+  PCRE_EXTRA_MATCH_LIMIT_RECURSION
+  PCRE_EXTRA_STUDY_DATA
+  PCRE_EXTRA_TABLES
+.sp
+Other flag bits should be set to zero. The \fIstudy_data\fP field and sometimes
+the \fIexecutable_jit\fP field are set in the \fBpcre_extra\fP block that is
+returned by \fBpcre_study()\fP, together with the appropriate flag bits. You
+should not set these yourself, but you may add to the block by setting other
+fields and their corresponding flag bits.
+.P
+The \fImatch_limit\fP field provides a means of preventing PCRE from using up a
+vast amount of resources when running patterns that are not going to match,
+but which have a very large number of possibilities in their search trees. The
+classic example is a pattern that uses nested unlimited repeats.
+.P
+Internally, \fBpcre_exec()\fP uses a function called \fBmatch()\fP, which it
+calls repeatedly (sometimes recursively). The limit set by \fImatch_limit\fP is
+imposed on the number of times this function is called during a match, which
+has the effect of limiting the amount of backtracking that can take place. For
+patterns that are not anchored, the count restarts from zero for each position
+in the subject string.
+.P
+When \fBpcre_exec()\fP is called with a pattern that was successfully studied
+with a JIT option, the way that the matching is executed is entirely different.
+However, there is still the possibility of runaway matching that goes on for a
+very long time, and so the \fImatch_limit\fP value is also used in this case
+(but in a different way) to limit how long the matching can continue.
+.P
+The default value for the limit can be set when PCRE is built; the default
+default is 10 million, which handles all but the most extreme cases. You can
+override the default by suppling \fBpcre_exec()\fP with a \fBpcre_extra\fP
+block in which \fImatch_limit\fP is set, and PCRE_EXTRA_MATCH_LIMIT is set in
+the \fIflags\fP field. If the limit is exceeded, \fBpcre_exec()\fP returns
+PCRE_ERROR_MATCHLIMIT.
+.P
+A value for the match limit may also be supplied by an item at the start of a
+pattern of the form
+.sp
+  (*LIMIT_MATCH=d)
+.sp
+where d is a decimal number. However, such a setting is ignored unless d is
+less than the limit set by the caller of \fBpcre_exec()\fP or, if no such limit
+is set, less than the default.
+.P
+The \fImatch_limit_recursion\fP field is similar to \fImatch_limit\fP, but
+instead of limiting the total number of times that \fBmatch()\fP is called, it
+limits the depth of recursion. The recursion depth is a smaller number than the
+total number of calls, because not all calls to \fBmatch()\fP are recursive.
+This limit is of use only if it is set smaller than \fImatch_limit\fP.
+.P
+Limiting the recursion depth limits the amount of machine stack that can be
+used, or, when PCRE has been compiled to use memory on the heap instead of the
+stack, the amount of heap memory that can be used. This limit is not relevant,
+and is ignored, when matching is done using JIT compiled code.
+.P
+The default value for \fImatch_limit_recursion\fP can be set when PCRE is
+built; the default default is the same value as the default for
+\fImatch_limit\fP. You can override the default by suppling \fBpcre_exec()\fP
+with a \fBpcre_extra\fP block in which \fImatch_limit_recursion\fP is set, and
+PCRE_EXTRA_MATCH_LIMIT_RECURSION is set in the \fIflags\fP field. If the limit
+is exceeded, \fBpcre_exec()\fP returns PCRE_ERROR_RECURSIONLIMIT.
+.P
+A value for the recursion limit may also be supplied by an item at the start of
+a pattern of the form
+.sp
+  (*LIMIT_RECURSION=d)
+.sp
+where d is a decimal number. However, such a setting is ignored unless d is
+less than the limit set by the caller of \fBpcre_exec()\fP or, if no such limit
+is set, less than the default.
+.P
+The \fIcallout_data\fP field is used in conjunction with the "callout" feature,
+and is described in the
+.\" HREF
+\fBpcrecallout\fP
+.\"
+documentation.
+.P
+The \fItables\fP field is provided for use with patterns that have been
+pre-compiled using custom character tables, saved to disc or elsewhere, and
+then reloaded, because the tables that were used to compile a pattern are not
+saved with it. See the
+.\" HREF
+\fBpcreprecompile\fP
+.\"
+documentation for a discussion of saving compiled patterns for later use. If
+NULL is passed using this mechanism, it forces PCRE's internal tables to be
+used.
+.P
+\fBWarning:\fP The tables that \fBpcre_exec()\fP uses must be the same as those
+that were used when the pattern was compiled. If this is not the case, the
+behaviour of \fBpcre_exec()\fP is undefined. Therefore, when a pattern is
+compiled and matched in the same process, this field should never be set. In
+this (the most common) case, the correct table pointer is automatically passed
+with the compiled pattern from \fBpcre_compile()\fP to \fBpcre_exec()\fP.
+.P
+If PCRE_EXTRA_MARK is set in the \fIflags\fP field, the \fImark\fP field must
+be set to point to a suitable variable. If the pattern contains any
+backtracking control verbs such as (*MARK:NAME), and the execution ends up with
+a name to pass back, a pointer to the name string (zero terminated) is placed
+in the variable pointed to by the \fImark\fP field. The names are within the
+compiled pattern; if you wish to retain such a name you must copy it before
+freeing the memory of a compiled pattern. If there is no name to pass back, the
+variable pointed to by the \fImark\fP field is set to NULL. For details of the
+backtracking control verbs, see the section entitled
+.\" HTML <a href="pcrepattern#backtrackcontrol">
+.\" </a>
+"Backtracking control"
+.\"
+in the
+.\" HREF
+\fBpcrepattern\fP
+.\"
+documentation.
+.
+.
+.\" HTML <a name="execoptions"></a>
+.SS "Option bits for \fBpcre_exec()\fP"
+.rs
+.sp
+The unused bits of the \fIoptions\fP argument for \fBpcre_exec()\fP must be
+zero. The only bits that may be set are PCRE_ANCHORED, PCRE_NEWLINE_\fIxxx\fP,
+PCRE_NOTBOL, PCRE_NOTEOL, PCRE_NOTEMPTY, PCRE_NOTEMPTY_ATSTART,
+PCRE_NO_START_OPTIMIZE, PCRE_NO_UTF8_CHECK, PCRE_PARTIAL_HARD, and
+PCRE_PARTIAL_SOFT.
+.P
+If the pattern was successfully studied with one of the just-in-time (JIT)
+compile options, the only supported options for JIT execution are
+PCRE_NO_UTF8_CHECK, PCRE_NOTBOL, PCRE_NOTEOL, PCRE_NOTEMPTY,
+PCRE_NOTEMPTY_ATSTART, PCRE_PARTIAL_HARD, and PCRE_PARTIAL_SOFT. If an
+unsupported option is used, JIT execution is disabled and the normal
+interpretive code in \fBpcre_exec()\fP is run.
+.sp
+  PCRE_ANCHORED
+.sp
+The PCRE_ANCHORED option limits \fBpcre_exec()\fP to matching at the first
+matching position. If a pattern was compiled with PCRE_ANCHORED, or turned out
+to be anchored by virtue of its contents, it cannot be made unachored at
+matching time.
+.sp
+  PCRE_BSR_ANYCRLF
+  PCRE_BSR_UNICODE
+.sp
+These options (which are mutually exclusive) control what the \eR escape
+sequence matches. The choice is either to match only CR, LF, or CRLF, or to
+match any Unicode newline sequence. These options override the choice that was
+made or defaulted when the pattern was compiled.
+.sp
+  PCRE_NEWLINE_CR
+  PCRE_NEWLINE_LF
+  PCRE_NEWLINE_CRLF
+  PCRE_NEWLINE_ANYCRLF
+  PCRE_NEWLINE_ANY
+.sp
+These options override the newline definition that was chosen or defaulted when
+the pattern was compiled. For details, see the description of
+\fBpcre_compile()\fP above. During matching, the newline choice affects the
+behaviour of the dot, circumflex, and dollar metacharacters. It may also alter
+the way the match position is advanced after a match failure for an unanchored
+pattern.
+.P
+When PCRE_NEWLINE_CRLF, PCRE_NEWLINE_ANYCRLF, or PCRE_NEWLINE_ANY is set, and a
+match attempt for an unanchored pattern fails when the current position is at a
+CRLF sequence, and the pattern contains no explicit matches for CR or LF
+characters, the match position is advanced by two characters instead of one, in
+other words, to after the CRLF.
+.P
+The above rule is a compromise that makes the most common cases work as
+expected. For example, if the pattern is .+A (and the PCRE_DOTALL option is not
+set), it does not match the string "\er\enA" because, after failing at the
+start, it skips both the CR and the LF before retrying. However, the pattern
+[\er\en]A does match that string, because it contains an explicit CR or LF
+reference, and so advances only by one character after the first failure.
+.P
+An explicit match for CR of LF is either a literal appearance of one of those
+characters, or one of the \er or \en escape sequences. Implicit matches such as
+[^X] do not count, nor does \es (which includes CR and LF in the characters
+that it matches).
+.P
+Notwithstanding the above, anomalous effects may still occur when CRLF is a
+valid newline sequence and explicit \er or \en escapes appear in the pattern.
+.sp
+  PCRE_NOTBOL
+.sp
+This option specifies that first character of the subject string is not the
+beginning of a line, so the circumflex metacharacter should not match before
+it. Setting this without PCRE_MULTILINE (at compile time) causes circumflex
+never to match. This option affects only the behaviour of the circumflex
+metacharacter. It does not affect \eA.
+.sp
+  PCRE_NOTEOL
+.sp
+This option specifies that the end of the subject string is not the end of a
+line, so the dollar metacharacter should not match it nor (except in multiline
+mode) a newline immediately before it. Setting this without PCRE_MULTILINE (at
+compile time) causes dollar never to match. This option affects only the
+behaviour of the dollar metacharacter. It does not affect \eZ or \ez.
+.sp
+  PCRE_NOTEMPTY
+.sp
+An empty string is not considered to be a valid match if this option is set. If
+there are alternatives in the pattern, they are tried. If all the alternatives
+match the empty string, the entire match fails. For example, if the pattern
+.sp
+  a?b?
+.sp
+is applied to a string not beginning with "a" or "b", it matches an empty
+string at the start of the subject. With PCRE_NOTEMPTY set, this match is not
+valid, so PCRE searches further into the string for occurrences of "a" or "b".
+.sp
+  PCRE_NOTEMPTY_ATSTART
+.sp
+This is like PCRE_NOTEMPTY, except that an empty string match that is not at
+the start of the subject is permitted. If the pattern is anchored, such a match
+can occur only if the pattern contains \eK.
+.P
+Perl has no direct equivalent of PCRE_NOTEMPTY or PCRE_NOTEMPTY_ATSTART, but it
+does make a special case of a pattern match of the empty string within its
+\fBsplit()\fP function, and when using the /g modifier. It is possible to
+emulate Perl's behaviour after matching a null string by first trying the match
+again at the same offset with PCRE_NOTEMPTY_ATSTART and PCRE_ANCHORED, and then
+if that fails, by advancing the starting offset (see below) and trying an
+ordinary match again. There is some code that demonstrates how to do this in
+the
+.\" HREF
+\fBpcredemo\fP
+.\"
+sample program. In the most general case, you have to check to see if the
+newline convention recognizes CRLF as a newline, and if so, and the current
+character is CR followed by LF, advance the starting offset by two characters
+instead of one.
+.sp
+  PCRE_NO_START_OPTIMIZE
+.sp
+There are a number of optimizations that \fBpcre_exec()\fP uses at the start of
+a match, in order to speed up the process. For example, if it is known that an
+unanchored match must start with a specific character, it searches the subject
+for that character, and fails immediately if it cannot find it, without
+actually running the main matching function. This means that a special item
+such as (*COMMIT) at the start of a pattern is not considered until after a
+suitable starting point for the match has been found. Also, when callouts or
+(*MARK) items are in use, these "start-up" optimizations can cause them to be
+skipped if the pattern is never actually used. The start-up optimizations are
+in effect a pre-scan of the subject that takes place before the pattern is run.
+.P
+The PCRE_NO_START_OPTIMIZE option disables the start-up optimizations, possibly
+causing performance to suffer, but ensuring that in cases where the result is
+"no match", the callouts do occur, and that items such as (*COMMIT) and (*MARK)
+are considered at every possible starting position in the subject string. If
+PCRE_NO_START_OPTIMIZE is set at compile time, it cannot be unset at matching
+time. The use of PCRE_NO_START_OPTIMIZE at matching time (that is, passing it
+to \fBpcre_exec()\fP) disables JIT execution; in this situation, matching is
+always done using interpretively.
+.P
+Setting PCRE_NO_START_OPTIMIZE can change the outcome of a matching operation.
+Consider the pattern
+.sp
+  (*COMMIT)ABC
+.sp
+When this is compiled, PCRE records the fact that a match must start with the
+character "A". Suppose the subject string is "DEFABC". The start-up
+optimization scans along the subject, finds "A" and runs the first match
+attempt from there. The (*COMMIT) item means that the pattern must match the
+current starting position, which in this case, it does. However, if the same
+match is run with PCRE_NO_START_OPTIMIZE set, the initial scan along the
+subject string does not happen. The first match attempt is run starting from
+"D" and when this fails, (*COMMIT) prevents any further matches being tried, so
+the overall result is "no match". If the pattern is studied, more start-up
+optimizations may be used. For example, a minimum length for the subject may be
+recorded. Consider the pattern
+.sp
+  (*MARK:A)(X|Y)
+.sp
+The minimum length for a match is one character. If the subject is "ABC", there
+will be attempts to match "ABC", "BC", "C", and then finally an empty string.
+If the pattern is studied, the final attempt does not take place, because PCRE
+knows that the subject is too short, and so the (*MARK) is never encountered.
+In this case, studying the pattern does not affect the overall match result,
+which is still "no match", but it does affect the auxiliary information that is
+returned.
+.sp
+  PCRE_NO_UTF8_CHECK
+.sp
+When PCRE_UTF8 is set at compile time, the validity of the subject as a UTF-8
+string is automatically checked when \fBpcre_exec()\fP is subsequently called.
+The entire string is checked before any other processing takes place. The value
+of \fIstartoffset\fP is also checked to ensure that it points to the start of a
+UTF-8 character. There is a discussion about the
+.\" HTML <a href="pcreunicode.html#utf8strings">
+.\" </a>
+validity of UTF-8 strings
+.\"
+in the
+.\" HREF
+\fBpcreunicode\fP
+.\"
+page. If an invalid sequence of bytes is found, \fBpcre_exec()\fP returns the
+error PCRE_ERROR_BADUTF8 or, if PCRE_PARTIAL_HARD is set and the problem is a
+truncated character at the end of the subject, PCRE_ERROR_SHORTUTF8. In both
+cases, information about the precise nature of the error may also be returned
+(see the descriptions of these errors in the section entitled \fIError return
+values from\fP \fBpcre_exec()\fP
+.\" HTML <a href="#errorlist">
+.\" </a>
+below).
+.\"
+If \fIstartoffset\fP contains a value that does not point to the start of a
+UTF-8 character (or to the end of the subject), PCRE_ERROR_BADUTF8_OFFSET is
+returned.
+.P
+If you already know that your subject is valid, and you want to skip these
+checks for performance reasons, you can set the PCRE_NO_UTF8_CHECK option when
+calling \fBpcre_exec()\fP. You might want to do this for the second and
+subsequent calls to \fBpcre_exec()\fP if you are making repeated calls to find
+all the matches in a single subject string. However, you should be sure that
+the value of \fIstartoffset\fP points to the start of a character (or the end
+of the subject). When PCRE_NO_UTF8_CHECK is set, the effect of passing an
+invalid string as a subject or an invalid value of \fIstartoffset\fP is
+undefined. Your program may crash or loop.
+.sp
+  PCRE_PARTIAL_HARD
+  PCRE_PARTIAL_SOFT
+.sp
+These options turn on the partial matching feature. For backwards
+compatibility, PCRE_PARTIAL is a synonym for PCRE_PARTIAL_SOFT. A partial match
+occurs if the end of the subject string is reached successfully, but there are
+not enough subject characters to complete the match. If this happens when
+PCRE_PARTIAL_SOFT (but not PCRE_PARTIAL_HARD) is set, matching continues by
+testing any remaining alternatives. Only if no complete match can be found is
+PCRE_ERROR_PARTIAL returned instead of PCRE_ERROR_NOMATCH. In other words,
+PCRE_PARTIAL_SOFT says that the caller is prepared to handle a partial match,
+but only if no complete match can be found.
+.P
+If PCRE_PARTIAL_HARD is set, it overrides PCRE_PARTIAL_SOFT. In this case, if a
+partial match is found, \fBpcre_exec()\fP immediately returns
+PCRE_ERROR_PARTIAL, without considering any other alternatives. In other words,
+when PCRE_PARTIAL_HARD is set, a partial match is considered to be more
+important that an alternative complete match.
+.P
+In both cases, the portion of the string that was inspected when the partial
+match was found is set as the first matching string. There is a more detailed
+discussion of partial and multi-segment matching, with examples, in the
+.\" HREF
+\fBpcrepartial\fP
+.\"
+documentation.
+.
+.
+.SS "The string to be matched by \fBpcre_exec()\fP"
+.rs
+.sp
+The subject string is passed to \fBpcre_exec()\fP as a pointer in
+\fIsubject\fP, a length in \fIlength\fP, and a starting offset in
+\fIstartoffset\fP. The units for \fIlength\fP and \fIstartoffset\fP are bytes
+for the 8-bit library, 16-bit data items for the 16-bit library, and 32-bit
+data items for the 32-bit library.
+.P
+If \fIstartoffset\fP is negative or greater than the length of the subject,
+\fBpcre_exec()\fP returns PCRE_ERROR_BADOFFSET. When the starting offset is
+zero, the search for a match starts at the beginning of the subject, and this
+is by far the most common case. In UTF-8 or UTF-16 mode, the offset must point
+to the start of a character, or the end of the subject (in UTF-32 mode, one
+data unit equals one character, so all offsets are valid). Unlike the pattern
+string, the subject may contain binary zeroes.
+.P
+A non-zero starting offset is useful when searching for another match in the
+same subject by calling \fBpcre_exec()\fP again after a previous success.
+Setting \fIstartoffset\fP differs from just passing over a shortened string and
+setting PCRE_NOTBOL in the case of a pattern that begins with any kind of
+lookbehind. For example, consider the pattern
+.sp
+  \eBiss\eB
+.sp
+which finds occurrences of "iss" in the middle of words. (\eB matches only if
+the current position in the subject is not a word boundary.) When applied to
+the string "Mississipi" the first call to \fBpcre_exec()\fP finds the first
+occurrence. If \fBpcre_exec()\fP is called again with just the remainder of the
+subject, namely "issipi", it does not match, because \eB is always false at the
+start of the subject, which is deemed to be a word boundary. However, if
+\fBpcre_exec()\fP is passed the entire string again, but with \fIstartoffset\fP
+set to 4, it finds the second occurrence of "iss" because it is able to look
+behind the starting point to discover that it is preceded by a letter.
+.P
+Finding all the matches in a subject is tricky when the pattern can match an
+empty string. It is possible to emulate Perl's /g behaviour by first trying the
+match again at the same offset, with the PCRE_NOTEMPTY_ATSTART and
+PCRE_ANCHORED options, and then if that fails, advancing the starting offset
+and trying an ordinary match again. There is some code that demonstrates how to
+do this in the
+.\" HREF
+\fBpcredemo\fP
+.\"
+sample program. In the most general case, you have to check to see if the
+newline convention recognizes CRLF as a newline, and if so, and the current
+character is CR followed by LF, advance the starting offset by two characters
+instead of one.
+.P
+If a non-zero starting offset is passed when the pattern is anchored, one
+attempt to match at the given offset is made. This can only succeed if the
+pattern does not require the match to be at the start of the subject.
+.
+.
+.SS "How \fBpcre_exec()\fP returns captured substrings"
+.rs
+.sp
+In general, a pattern matches a certain portion of the subject, and in
+addition, further substrings from the subject may be picked out by parts of the
+pattern. Following the usage in Jeffrey Friedl's book, this is called
+"capturing" in what follows, and the phrase "capturing subpattern" is used for
+a fragment of a pattern that picks out a substring. PCRE supports several other
+kinds of parenthesized subpattern that do not cause substrings to be captured.
+.P
+Captured substrings are returned to the caller via a vector of integers whose
+address is passed in \fIovector\fP. The number of elements in the vector is
+passed in \fIovecsize\fP, which must be a non-negative number. \fBNote\fP: this
+argument is NOT the size of \fIovector\fP in bytes.
+.P
+The first two-thirds of the vector is used to pass back captured substrings,
+each substring using a pair of integers. The remaining third of the vector is
+used as workspace by \fBpcre_exec()\fP while matching capturing subpatterns,
+and is not available for passing back information. The number passed in
+\fIovecsize\fP should always be a multiple of three. If it is not, it is
+rounded down.
+.P
+When a match is successful, information about captured substrings is returned
+in pairs of integers, starting at the beginning of \fIovector\fP, and
+continuing up to two-thirds of its length at the most. The first element of
+each pair is set to the offset of the first character in a substring, and the
+second is set to the offset of the first character after the end of a
+substring. These values are always data unit offsets, even in UTF mode. They
+are byte offsets in the 8-bit library, 16-bit data item offsets in the 16-bit
+library, and 32-bit data item offsets in the 32-bit library. \fBNote\fP: they
+are not character counts.
+.P
+The first pair of integers, \fIovector[0]\fP and \fIovector[1]\fP, identify the
+portion of the subject string matched by the entire pattern. The next pair is
+used for the first capturing subpattern, and so on. The value returned by
+\fBpcre_exec()\fP is one more than the highest numbered pair that has been set.
+For example, if two substrings have been captured, the returned value is 3. If
+there are no capturing subpatterns, the return value from a successful match is
+1, indicating that just the first pair of offsets has been set.
+.P
+If a capturing subpattern is matched repeatedly, it is the last portion of the
+string that it matched that is returned.
+.P
+If the vector is too small to hold all the captured substring offsets, it is
+used as far as possible (up to two-thirds of its length), and the function
+returns a value of zero. If neither the actual string matched nor any captured
+substrings are of interest, \fBpcre_exec()\fP may be called with \fIovector\fP
+passed as NULL and \fIovecsize\fP as zero. However, if the pattern contains
+back references and the \fIovector\fP is not big enough to remember the related
+substrings, PCRE has to get additional memory for use during matching. Thus it
+is usually advisable to supply an \fIovector\fP of reasonable size.
+.P
+There are some cases where zero is returned (indicating vector overflow) when
+in fact the vector is exactly the right size for the final match. For example,
+consider the pattern
+.sp
+  (a)(?:(b)c|bd)
+.sp
+If a vector of 6 elements (allowing for only 1 captured substring) is given
+with subject string "abd", \fBpcre_exec()\fP will try to set the second
+captured string, thereby recording a vector overflow, before failing to match
+"c" and backing up to try the second alternative. The zero return, however,
+does correctly indicate that the maximum number of slots (namely 2) have been
+filled. In similar cases where there is temporary overflow, but the final
+number of used slots is actually less than the maximum, a non-zero value is
+returned.
+.P
+The \fBpcre_fullinfo()\fP function can be used to find out how many capturing
+subpatterns there are in a compiled pattern. The smallest size for
+\fIovector\fP that will allow for \fIn\fP captured substrings, in addition to
+the offsets of the substring matched by the whole pattern, is (\fIn\fP+1)*3.
+.P
+It is possible for capturing subpattern number \fIn+1\fP to match some part of
+the subject when subpattern \fIn\fP has not been used at all. For example, if
+the string "abc" is matched against the pattern (a|(z))(bc) the return from the
+function is 4, and subpatterns 1 and 3 are matched, but 2 is not. When this
+happens, both values in the offset pairs corresponding to unused subpatterns
+are set to -1.
+.P
+Offset values that correspond to unused subpatterns at the end of the
+expression are also set to -1. For example, if the string "abc" is matched
+against the pattern (abc)(x(yz)?)? subpatterns 2 and 3 are not matched. The
+return from the function is 2, because the highest used capturing subpattern
+number is 1, and the offsets for for the second and third capturing subpatterns
+(assuming the vector is large enough, of course) are set to -1.
+.P
+\fBNote\fP: Elements in the first two-thirds of \fIovector\fP that do not
+correspond to capturing parentheses in the pattern are never changed. That is,
+if a pattern contains \fIn\fP capturing parentheses, no more than
+\fIovector[0]\fP to \fIovector[2n+1]\fP are set by \fBpcre_exec()\fP. The other
+elements (in the first two-thirds) retain whatever values they previously had.
+.P
+Some convenience functions are provided for extracting the captured substrings
+as separate strings. These are described below.
+.
+.
+.\" HTML <a name="errorlist"></a>
+.SS "Error return values from \fBpcre_exec()\fP"
+.rs
+.sp
+If \fBpcre_exec()\fP fails, it returns a negative number. The following are
+defined in the header file:
+.sp
+  PCRE_ERROR_NOMATCH        (-1)
+.sp
+The subject string did not match the pattern.
+.sp
+  PCRE_ERROR_NULL           (-2)
+.sp
+Either \fIcode\fP or \fIsubject\fP was passed as NULL, or \fIovector\fP was
+NULL and \fIovecsize\fP was not zero.
+.sp
+  PCRE_ERROR_BADOPTION      (-3)
+.sp
+An unrecognized bit was set in the \fIoptions\fP argument.
+.sp
+  PCRE_ERROR_BADMAGIC       (-4)
+.sp
+PCRE stores a 4-byte "magic number" at the start of the compiled code, to catch
+the case when it is passed a junk pointer and to detect when a pattern that was
+compiled in an environment of one endianness is run in an environment with the
+other endianness. This is the error that PCRE gives when the magic number is
+not present.
+.sp
+  PCRE_ERROR_UNKNOWN_OPCODE (-5)
+.sp
+While running the pattern match, an unknown item was encountered in the
+compiled pattern. This error could be caused by a bug in PCRE or by overwriting
+of the compiled pattern.
+.sp
+  PCRE_ERROR_NOMEMORY       (-6)
+.sp
+If a pattern contains back references, but the \fIovector\fP that is passed to
+\fBpcre_exec()\fP is not big enough to remember the referenced substrings, PCRE
+gets a block of memory at the start of matching to use for this purpose. If the
+call via \fBpcre_malloc()\fP fails, this error is given. The memory is
+automatically freed at the end of matching.
+.P
+This error is also given if \fBpcre_stack_malloc()\fP fails in
+\fBpcre_exec()\fP. This can happen only when PCRE has been compiled with
+\fB--disable-stack-for-recursion\fP.
+.sp
+  PCRE_ERROR_NOSUBSTRING    (-7)
+.sp
+This error is used by the \fBpcre_copy_substring()\fP,
+\fBpcre_get_substring()\fP, and \fBpcre_get_substring_list()\fP functions (see
+below). It is never returned by \fBpcre_exec()\fP.
+.sp
+  PCRE_ERROR_MATCHLIMIT     (-8)
+.sp
+The backtracking limit, as specified by the \fImatch_limit\fP field in a
+\fBpcre_extra\fP structure (or defaulted) was reached. See the description
+above.
+.sp
+  PCRE_ERROR_CALLOUT        (-9)
+.sp
+This error is never generated by \fBpcre_exec()\fP itself. It is provided for
+use by callout functions that want to yield a distinctive error code. See the
+.\" HREF
+\fBpcrecallout\fP
+.\"
+documentation for details.
+.sp
+  PCRE_ERROR_BADUTF8        (-10)
+.sp
+A string that contains an invalid UTF-8 byte sequence was passed as a subject,
+and the PCRE_NO_UTF8_CHECK option was not set. If the size of the output vector
+(\fIovecsize\fP) is at least 2, the byte offset to the start of the the invalid
+UTF-8 character is placed in the first element, and a reason code is placed in
+the second element. The reason codes are listed in the
+.\" HTML <a href="#badutf8reasons">
+.\" </a>
+following section.
+.\"
+For backward compatibility, if PCRE_PARTIAL_HARD is set and the problem is a
+truncated UTF-8 character at the end of the subject (reason codes 1 to 5),
+PCRE_ERROR_SHORTUTF8 is returned instead of PCRE_ERROR_BADUTF8.
+.sp
+  PCRE_ERROR_BADUTF8_OFFSET (-11)
+.sp
+The UTF-8 byte sequence that was passed as a subject was checked and found to
+be valid (the PCRE_NO_UTF8_CHECK option was not set), but the value of
+\fIstartoffset\fP did not point to the beginning of a UTF-8 character or the
+end of the subject.
+.sp
+  PCRE_ERROR_PARTIAL        (-12)
+.sp
+The subject string did not match, but it did match partially. See the
+.\" HREF
+\fBpcrepartial\fP
+.\"
+documentation for details of partial matching.
+.sp
+  PCRE_ERROR_BADPARTIAL     (-13)
+.sp
+This code is no longer in use. It was formerly returned when the PCRE_PARTIAL
+option was used with a compiled pattern containing items that were not
+supported for partial matching. From release 8.00 onwards, there are no
+restrictions on partial matching.
+.sp
+  PCRE_ERROR_INTERNAL       (-14)
+.sp
+An unexpected internal error has occurred. This error could be caused by a bug
+in PCRE or by overwriting of the compiled pattern.
+.sp
+  PCRE_ERROR_BADCOUNT       (-15)
+.sp
+This error is given if the value of the \fIovecsize\fP argument is negative.
+.sp
+  PCRE_ERROR_RECURSIONLIMIT (-21)
+.sp
+The internal recursion limit, as specified by the \fImatch_limit_recursion\fP
+field in a \fBpcre_extra\fP structure (or defaulted) was reached. See the
+description above.
+.sp
+  PCRE_ERROR_BADNEWLINE     (-23)
+.sp
+An invalid combination of PCRE_NEWLINE_\fIxxx\fP options was given.
+.sp
+  PCRE_ERROR_BADOFFSET      (-24)
+.sp
+The value of \fIstartoffset\fP was negative or greater than the length of the
+subject, that is, the value in \fIlength\fP.
+.sp
+  PCRE_ERROR_SHORTUTF8      (-25)
+.sp
+This error is returned instead of PCRE_ERROR_BADUTF8 when the subject string
+ends with a truncated UTF-8 character and the PCRE_PARTIAL_HARD option is set.
+Information about the failure is returned as for PCRE_ERROR_BADUTF8. It is in
+fact sufficient to detect this case, but this special error code for
+PCRE_PARTIAL_HARD precedes the implementation of returned information; it is
+retained for backwards compatibility.
+.sp
+  PCRE_ERROR_RECURSELOOP    (-26)
+.sp
+This error is returned when \fBpcre_exec()\fP detects a recursion loop within
+the pattern. Specifically, it means that either the whole pattern or a
+subpattern has been called recursively for the second time at the same position
+in the subject string. Some simple patterns that might do this are detected and
+faulted at compile time, but more complicated cases, in particular mutual
+recursions between two different subpatterns, cannot be detected until run
+time.
+.sp
+  PCRE_ERROR_JIT_STACKLIMIT (-27)
+.sp
+This error is returned when a pattern that was successfully studied using a
+JIT compile option is being matched, but the memory available for the
+just-in-time processing stack is not large enough. See the
+.\" HREF
+\fBpcrejit\fP
+.\"
+documentation for more details.
+.sp
+  PCRE_ERROR_BADMODE        (-28)
+.sp
+This error is given if a pattern that was compiled by the 8-bit library is
+passed to a 16-bit or 32-bit library function, or vice versa.
+.sp
+  PCRE_ERROR_BADENDIANNESS  (-29)
+.sp
+This error is given if a pattern that was compiled and saved is reloaded on a
+host with different endianness. The utility function
+\fBpcre_pattern_to_host_byte_order()\fP can be used to convert such a pattern
+so that it runs on the new host.
+.sp
+  PCRE_ERROR_JIT_BADOPTION
+.sp
+This error is returned when a pattern that was successfully studied using a JIT
+compile option is being matched, but the matching mode (partial or complete
+match) does not correspond to any JIT compilation mode. When the JIT fast path
+function is used, this error may be also given for invalid options. See the
+.\" HREF
+\fBpcrejit\fP
+.\"
+documentation for more details.
+.sp
+  PCRE_ERROR_BADLENGTH      (-32)
+.sp
+This error is given if \fBpcre_exec()\fP is called with a negative value for
+the \fIlength\fP argument.
+.P
+Error numbers -16 to -20, -22, and 30 are not used by \fBpcre_exec()\fP.
+.
+.
+.\" HTML <a name="badutf8reasons"></a>
+.SS "Reason codes for invalid UTF-8 strings"
+.rs
+.sp
+This section applies only to the 8-bit library. The corresponding information
+for the 16-bit and 32-bit libraries is given in the
+.\" HREF
+\fBpcre16\fP
+.\"
+and
+.\" HREF
+\fBpcre32\fP
+.\"
+pages.
+.P
+When \fBpcre_exec()\fP returns either PCRE_ERROR_BADUTF8 or
+PCRE_ERROR_SHORTUTF8, and the size of the output vector (\fIovecsize\fP) is at
+least 2, the offset of the start of the invalid UTF-8 character is placed in
+the first output vector element (\fIovector[0]\fP) and a reason code is placed
+in the second element (\fIovector[1]\fP). The reason codes are given names in
+the \fBpcre.h\fP header file:
+.sp
+  PCRE_UTF8_ERR1
+  PCRE_UTF8_ERR2
+  PCRE_UTF8_ERR3
+  PCRE_UTF8_ERR4
+  PCRE_UTF8_ERR5
+.sp
+The string ends with a truncated UTF-8 character; the code specifies how many
+bytes are missing (1 to 5). Although RFC 3629 restricts UTF-8 characters to be
+no longer than 4 bytes, the encoding scheme (originally defined by RFC 2279)
+allows for up to 6 bytes, and this is checked first; hence the possibility of
+4 or 5 missing bytes.
+.sp
+  PCRE_UTF8_ERR6
+  PCRE_UTF8_ERR7
+  PCRE_UTF8_ERR8
+  PCRE_UTF8_ERR9
+  PCRE_UTF8_ERR10
+.sp
+The two most significant bits of the 2nd, 3rd, 4th, 5th, or 6th byte of the
+character do not have the binary value 0b10 (that is, either the most
+significant bit is 0, or the next bit is 1).
+.sp
+  PCRE_UTF8_ERR11
+  PCRE_UTF8_ERR12
+.sp
+A character that is valid by the RFC 2279 rules is either 5 or 6 bytes long;
+these code points are excluded by RFC 3629.
+.sp
+  PCRE_UTF8_ERR13
+.sp
+A 4-byte character has a value greater than 0x10fff; these code points are
+excluded by RFC 3629.
+.sp
+  PCRE_UTF8_ERR14
+.sp
+A 3-byte character has a value in the range 0xd800 to 0xdfff; this range of
+code points are reserved by RFC 3629 for use with UTF-16, and so are excluded
+from UTF-8.
+.sp
+  PCRE_UTF8_ERR15
+  PCRE_UTF8_ERR16
+  PCRE_UTF8_ERR17
+  PCRE_UTF8_ERR18
+  PCRE_UTF8_ERR19
+.sp
+A 2-, 3-, 4-, 5-, or 6-byte character is "overlong", that is, it codes for a
+value that can be represented by fewer bytes, which is invalid. For example,
+the two bytes 0xc0, 0xae give the value 0x2e, whose correct coding uses just
+one byte.
+.sp
+  PCRE_UTF8_ERR20
+.sp
+The two most significant bits of the first byte of a character have the binary
+value 0b10 (that is, the most significant bit is 1 and the second is 0). Such a
+byte can only validly occur as the second or subsequent byte of a multi-byte
+character.
+.sp
+  PCRE_UTF8_ERR21
+.sp
+The first byte of a character has the value 0xfe or 0xff. These values can
+never occur in a valid UTF-8 string.
+.sp
+  PCRE_UTF8_ERR22
+.sp
+This error code was formerly used when the presence of a so-called
+"non-character" caused an error. Unicode corrigendum #9 makes it clear that
+such characters should not cause a string to be rejected, and so this code is
+no longer in use and is never returned.
+.
+.
+.SH "EXTRACTING CAPTURED SUBSTRINGS BY NUMBER"
+.rs
+.sp
+.nf
+.B int pcre_copy_substring(const char *\fIsubject\fP, int *\fIovector\fP,
+.B "     int \fIstringcount\fP, int \fIstringnumber\fP, char *\fIbuffer\fP,"
+.B "     int \fIbuffersize\fP);"
+.sp
+.B int pcre_get_substring(const char *\fIsubject\fP, int *\fIovector\fP,
+.B "     int \fIstringcount\fP, int \fIstringnumber\fP,"
+.B "     const char **\fIstringptr\fP);"
+.sp
+.B int pcre_get_substring_list(const char *\fIsubject\fP,
+.B "     int *\fIovector\fP, int \fIstringcount\fP, const char ***\fIlistptr\fP);"
+.fi
+.PP
+Captured substrings can be accessed directly by using the offsets returned by
+\fBpcre_exec()\fP in \fIovector\fP. For convenience, the functions
+\fBpcre_copy_substring()\fP, \fBpcre_get_substring()\fP, and
+\fBpcre_get_substring_list()\fP are provided for extracting captured substrings
+as new, separate, zero-terminated strings. These functions identify substrings
+by number. The next section describes functions for extracting named
+substrings.
+.P
+A substring that contains a binary zero is correctly extracted and has a
+further zero added on the end, but the result is not, of course, a C string.
+However, you can process such a string by referring to the length that is
+returned by \fBpcre_copy_substring()\fP and \fBpcre_get_substring()\fP.
+Unfortunately, the interface to \fBpcre_get_substring_list()\fP is not adequate
+for handling strings containing binary zeros, because the end of the final
+string is not independently indicated.
+.P
+The first three arguments are the same for all three of these functions:
+\fIsubject\fP is the subject string that has just been successfully matched,
+\fIovector\fP is a pointer to the vector of integer offsets that was passed to
+\fBpcre_exec()\fP, and \fIstringcount\fP is the number of substrings that were
+captured by the match, including the substring that matched the entire regular
+expression. This is the value returned by \fBpcre_exec()\fP if it is greater
+than zero. If \fBpcre_exec()\fP returned zero, indicating that it ran out of
+space in \fIovector\fP, the value passed as \fIstringcount\fP should be the
+number of elements in the vector divided by three.
+.P
+The functions \fBpcre_copy_substring()\fP and \fBpcre_get_substring()\fP
+extract a single substring, whose number is given as \fIstringnumber\fP. A
+value of zero extracts the substring that matched the entire pattern, whereas
+higher values extract the captured substrings. For \fBpcre_copy_substring()\fP,
+the string is placed in \fIbuffer\fP, whose length is given by
+\fIbuffersize\fP, while for \fBpcre_get_substring()\fP a new block of memory is
+obtained via \fBpcre_malloc\fP, and its address is returned via
+\fIstringptr\fP. The yield of the function is the length of the string, not
+including the terminating zero, or one of these error codes:
+.sp
+  PCRE_ERROR_NOMEMORY       (-6)
+.sp
+The buffer was too small for \fBpcre_copy_substring()\fP, or the attempt to get
+memory failed for \fBpcre_get_substring()\fP.
+.sp
+  PCRE_ERROR_NOSUBSTRING    (-7)
+.sp
+There is no substring whose number is \fIstringnumber\fP.
+.P
+The \fBpcre_get_substring_list()\fP function extracts all available substrings
+and builds a list of pointers to them. All this is done in a single block of
+memory that is obtained via \fBpcre_malloc\fP. The address of the memory block
+is returned via \fIlistptr\fP, which is also the start of the list of string
+pointers. The end of the list is marked by a NULL pointer. The yield of the
+function is zero if all went well, or the error code
+.sp
+  PCRE_ERROR_NOMEMORY       (-6)
+.sp
+if the attempt to get the memory block failed.
+.P
+When any of these functions encounter a substring that is unset, which can
+happen when capturing subpattern number \fIn+1\fP matches some part of the
+subject, but subpattern \fIn\fP has not been used at all, they return an empty
+string. This can be distinguished from a genuine zero-length substring by
+inspecting the appropriate offset in \fIovector\fP, which is negative for unset
+substrings.
+.P
+The two convenience functions \fBpcre_free_substring()\fP and
+\fBpcre_free_substring_list()\fP can be used to free the memory returned by
+a previous call of \fBpcre_get_substring()\fP or
+\fBpcre_get_substring_list()\fP, respectively. They do nothing more than call
+the function pointed to by \fBpcre_free\fP, which of course could be called
+directly from a C program. However, PCRE is used in some situations where it is
+linked via a special interface to another programming language that cannot use
+\fBpcre_free\fP directly; it is for these cases that the functions are
+provided.
+.
+.
+.SH "EXTRACTING CAPTURED SUBSTRINGS BY NAME"
+.rs
+.sp
+.nf
+.B int pcre_get_stringnumber(const pcre *\fIcode\fP,
+.B "     const char *\fIname\fP);"
+.sp
+.B int pcre_copy_named_substring(const pcre *\fIcode\fP,
+.B "     const char *\fIsubject\fP, int *\fIovector\fP,"
+.B "     int \fIstringcount\fP, const char *\fIstringname\fP,"
+.B "     char *\fIbuffer\fP, int \fIbuffersize\fP);"
+.sp
+.B int pcre_get_named_substring(const pcre *\fIcode\fP,
+.B "     const char *\fIsubject\fP, int *\fIovector\fP,"
+.B "     int \fIstringcount\fP, const char *\fIstringname\fP,"
+.B "     const char **\fIstringptr\fP);"
+.fi
+.PP
+To extract a substring by name, you first have to find associated number.
+For example, for this pattern
+.sp
+  (a+)b(?<xxx>\ed+)...
+.sp
+the number of the subpattern called "xxx" is 2. If the name is known to be
+unique (PCRE_DUPNAMES was not set), you can find the number from the name by
+calling \fBpcre_get_stringnumber()\fP. The first argument is the compiled
+pattern, and the second is the name. The yield of the function is the
+subpattern number, or PCRE_ERROR_NOSUBSTRING (-7) if there is no subpattern of
+that name.
+.P
+Given the number, you can extract the substring directly, or use one of the
+functions described in the previous section. For convenience, there are also
+two functions that do the whole job.
+.P
+Most of the arguments of \fBpcre_copy_named_substring()\fP and
+\fBpcre_get_named_substring()\fP are the same as those for the similarly named
+functions that extract by number. As these are described in the previous
+section, they are not re-described here. There are just two differences:
+.P
+First, instead of a substring number, a substring name is given. Second, there
+is an extra argument, given at the start, which is a pointer to the compiled
+pattern. This is needed in order to gain access to the name-to-number
+translation table.
+.P
+These functions call \fBpcre_get_stringnumber()\fP, and if it succeeds, they
+then call \fBpcre_copy_substring()\fP or \fBpcre_get_substring()\fP, as
+appropriate. \fBNOTE:\fP If PCRE_DUPNAMES is set and there are duplicate names,
+the behaviour may not be what you want (see the next section).
+.P
+\fBWarning:\fP If the pattern uses the (?| feature to set up multiple
+subpatterns with the same number, as described in the
+.\" HTML <a href="pcrepattern.html#dupsubpatternnumber">
+.\" </a>
+section on duplicate subpattern numbers
+.\"
+in the
+.\" HREF
+\fBpcrepattern\fP
+.\"
+page, you cannot use names to distinguish the different subpatterns, because
+names are not included in the compiled code. The matching process uses only
+numbers. For this reason, the use of different names for subpatterns of the
+same number causes an error at compile time.
+.
+.
+.SH "DUPLICATE SUBPATTERN NAMES"
+.rs
+.sp
+.nf
+.B int pcre_get_stringtable_entries(const pcre *\fIcode\fP,
+.B "     const char *\fIname\fP, char **\fIfirst\fP, char **\fIlast\fP);"
+.fi
+.PP
+When a pattern is compiled with the PCRE_DUPNAMES option, names for subpatterns
+are not required to be unique. (Duplicate names are always allowed for
+subpatterns with the same number, created by using the (?| feature. Indeed, if
+such subpatterns are named, they are required to use the same names.)
+.P
+Normally, patterns with duplicate names are such that in any one match, only
+one of the named subpatterns participates. An example is shown in the
+.\" HREF
+\fBpcrepattern\fP
+.\"
+documentation.
+.P
+When duplicates are present, \fBpcre_copy_named_substring()\fP and
+\fBpcre_get_named_substring()\fP return the first substring corresponding to
+the given name that is set. If none are set, PCRE_ERROR_NOSUBSTRING (-7) is
+returned; no data is returned. The \fBpcre_get_stringnumber()\fP function
+returns one of the numbers that are associated with the name, but it is not
+defined which it is.
+.P
+If you want to get full details of all captured substrings for a given name,
+you must use the \fBpcre_get_stringtable_entries()\fP function. The first
+argument is the compiled pattern, and the second is the name. The third and
+fourth are pointers to variables which are updated by the function. After it
+has run, they point to the first and last entries in the name-to-number table
+for the given name. The function itself returns the length of each entry, or
+PCRE_ERROR_NOSUBSTRING (-7) if there are none. The format of the table is
+described above in the section entitled \fIInformation about a pattern\fP
+.\" HTML <a href="#infoaboutpattern">
+.\" </a>
+above.
+.\"
+Given all the relevant entries for the name, you can extract each of their
+numbers, and hence the captured data, if any.
+.
+.
+.SH "FINDING ALL POSSIBLE MATCHES"
+.rs
+.sp
+The traditional matching function uses a similar algorithm to Perl, which stops
+when it finds the first match, starting at a given point in the subject. If you
+want to find all possible matches, or the longest possible match, consider
+using the alternative matching function (see below) instead. If you cannot use
+the alternative function, but still need to find all possible matches, you
+can kludge it up by making use of the callout facility, which is described in
+the
+.\" HREF
+\fBpcrecallout\fP
+.\"
+documentation.
+.P
+What you have to do is to insert a callout right at the end of the pattern.
+When your callout function is called, extract and save the current matched
+substring. Then return 1, which forces \fBpcre_exec()\fP to backtrack and try
+other alternatives. Ultimately, when it runs out of matches, \fBpcre_exec()\fP
+will yield PCRE_ERROR_NOMATCH.
+.
+.
+.SH "OBTAINING AN ESTIMATE OF STACK USAGE"
+.rs
+.sp
+Matching certain patterns using \fBpcre_exec()\fP can use a lot of process
+stack, which in certain environments can be rather limited in size. Some users
+find it helpful to have an estimate of the amount of stack that is used by
+\fBpcre_exec()\fP, to help them set recursion limits, as described in the
+.\" HREF
+\fBpcrestack\fP
+.\"
+documentation. The estimate that is output by \fBpcretest\fP when called with
+the \fB-m\fP and \fB-C\fP options is obtained by calling \fBpcre_exec\fP with
+the values NULL, NULL, NULL, -999, and -999 for its first five arguments.
+.P
+Normally, if its first argument is NULL, \fBpcre_exec()\fP immediately returns
+the negative error code PCRE_ERROR_NULL, but with this special combination of
+arguments, it returns instead a negative number whose absolute value is the
+approximate stack frame size in bytes. (A negative number is used so that it is
+clear that no match has happened.) The value is approximate because in some
+cases, recursive calls to \fBpcre_exec()\fP occur when there are one or two
+additional variables on the stack.
+.P
+If PCRE has been compiled to use the heap instead of the stack for recursion,
+the value returned is the size of each block that is obtained from the heap.
+.
+.
+.\" HTML <a name="dfamatch"></a>
+.SH "MATCHING A PATTERN: THE ALTERNATIVE FUNCTION"
+.rs
+.sp
+.nf
+.B int pcre_dfa_exec(const pcre *\fIcode\fP, "const pcre_extra *\fIextra\fP,"
+.B "     const char *\fIsubject\fP, int \fIlength\fP, int \fIstartoffset\fP,"
+.B "     int \fIoptions\fP, int *\fIovector\fP, int \fIovecsize\fP,"
+.B "     int *\fIworkspace\fP, int \fIwscount\fP);"
+.fi
+.P
+The function \fBpcre_dfa_exec()\fP is called to match a subject string against
+a compiled pattern, using a matching algorithm that scans the subject string
+just once, and does not backtrack. This has different characteristics to the
+normal algorithm, and is not compatible with Perl. Some of the features of PCRE
+patterns are not supported. Nevertheless, there are times when this kind of
+matching can be useful. For a discussion of the two matching algorithms, and a
+list of features that \fBpcre_dfa_exec()\fP does not support, see the
+.\" HREF
+\fBpcrematching\fP
+.\"
+documentation.
+.P
+The arguments for the \fBpcre_dfa_exec()\fP function are the same as for
+\fBpcre_exec()\fP, plus two extras. The \fIovector\fP argument is used in a
+different way, and this is described below. The other common arguments are used
+in the same way as for \fBpcre_exec()\fP, so their description is not repeated
+here.
+.P
+The two additional arguments provide workspace for the function. The workspace
+vector should contain at least 20 elements. It is used for keeping track of
+multiple paths through the pattern tree. More workspace will be needed for
+patterns and subjects where there are a lot of potential matches.
+.P
+Here is an example of a simple call to \fBpcre_dfa_exec()\fP:
+.sp
+  int rc;
+  int ovector[10];
+  int wspace[20];
+  rc = pcre_dfa_exec(
+    re,             /* result of pcre_compile() */
+    NULL,           /* we didn't study the pattern */
+    "some string",  /* the subject string */
+    11,             /* the length of the subject string */
+    0,              /* start at offset 0 in the subject */
+    0,              /* default options */
+    ovector,        /* vector of integers for substring information */
+    10,             /* number of elements (NOT size in bytes) */
+    wspace,         /* working space vector */
+    20);            /* number of elements (NOT size in bytes) */
+.
+.SS "Option bits for \fBpcre_dfa_exec()\fP"
+.rs
+.sp
+The unused bits of the \fIoptions\fP argument for \fBpcre_dfa_exec()\fP must be
+zero. The only bits that may be set are PCRE_ANCHORED, PCRE_NEWLINE_\fIxxx\fP,
+PCRE_NOTBOL, PCRE_NOTEOL, PCRE_NOTEMPTY, PCRE_NOTEMPTY_ATSTART,
+PCRE_NO_UTF8_CHECK, PCRE_BSR_ANYCRLF, PCRE_BSR_UNICODE, PCRE_NO_START_OPTIMIZE,
+PCRE_PARTIAL_HARD, PCRE_PARTIAL_SOFT, PCRE_DFA_SHORTEST, and PCRE_DFA_RESTART.
+All but the last four of these are exactly the same as for \fBpcre_exec()\fP,
+so their description is not repeated here.
+.sp
+  PCRE_PARTIAL_HARD
+  PCRE_PARTIAL_SOFT
+.sp
+These have the same general effect as they do for \fBpcre_exec()\fP, but the
+details are slightly different. When PCRE_PARTIAL_HARD is set for
+\fBpcre_dfa_exec()\fP, it returns PCRE_ERROR_PARTIAL if the end of the subject
+is reached and there is still at least one matching possibility that requires
+additional characters. This happens even if some complete matches have also
+been found. When PCRE_PARTIAL_SOFT is set, the return code PCRE_ERROR_NOMATCH
+is converted into PCRE_ERROR_PARTIAL if the end of the subject is reached,
+there have been no complete matches, but there is still at least one matching
+possibility. The portion of the string that was inspected when the longest
+partial match was found is set as the first matching string in both cases.
+There is a more detailed discussion of partial and multi-segment matching, with
+examples, in the
+.\" HREF
+\fBpcrepartial\fP
+.\"
+documentation.
+.sp
+  PCRE_DFA_SHORTEST
+.sp
+Setting the PCRE_DFA_SHORTEST option causes the matching algorithm to stop as
+soon as it has found one match. Because of the way the alternative algorithm
+works, this is necessarily the shortest possible match at the first possible
+matching point in the subject string.
+.sp
+  PCRE_DFA_RESTART
+.sp
+When \fBpcre_dfa_exec()\fP returns a partial match, it is possible to call it
+again, with additional subject characters, and have it continue with the same
+match. The PCRE_DFA_RESTART option requests this action; when it is set, the
+\fIworkspace\fP and \fIwscount\fP options must reference the same vector as
+before because data about the match so far is left in them after a partial
+match. There is more discussion of this facility in the
+.\" HREF
+\fBpcrepartial\fP
+.\"
+documentation.
+.
+.
+.SS "Successful returns from \fBpcre_dfa_exec()\fP"
+.rs
+.sp
+When \fBpcre_dfa_exec()\fP succeeds, it may have matched more than one
+substring in the subject. Note, however, that all the matches from one run of
+the function start at the same point in the subject. The shorter matches are
+all initial substrings of the longer matches. For example, if the pattern
+.sp
+  <.*>
+.sp
+is matched against the string
+.sp
+  This is <something> <something else> <something further> no more
+.sp
+the three matched strings are
+.sp
+  <something>
+  <something> <something else>
+  <something> <something else> <something further>
+.sp
+On success, the yield of the function is a number greater than zero, which is
+the number of matched substrings. The substrings themselves are returned in
+\fIovector\fP. Each string uses two elements; the first is the offset to the
+start, and the second is the offset to the end. In fact, all the strings have
+the same start offset. (Space could have been saved by giving this only once,
+but it was decided to retain some compatibility with the way \fBpcre_exec()\fP
+returns data, even though the meaning of the strings is different.)
+.P
+The strings are returned in reverse order of length; that is, the longest
+matching string is given first. If there were too many matches to fit into
+\fIovector\fP, the yield of the function is zero, and the vector is filled with
+the longest matches. Unlike \fBpcre_exec()\fP, \fBpcre_dfa_exec()\fP can use
+the entire \fIovector\fP for returning matched strings.
+.P
+NOTE: PCRE's "auto-possessification" optimization usually applies to character
+repeats at the end of a pattern (as well as internally). For example, the
+pattern "a\ed+" is compiled as if it were "a\ed++" because there is no point
+even considering the possibility of backtracking into the repeated digits. For
+DFA matching, this means that only one possible match is found. If you really
+do want multiple matches in such cases, either use an ungreedy repeat
+("a\ed+?") or set the PCRE_NO_AUTO_POSSESS option when compiling.
+.
+.
+.SS "Error returns from \fBpcre_dfa_exec()\fP"
+.rs
+.sp
+The \fBpcre_dfa_exec()\fP function returns a negative number when it fails.
+Many of the errors are the same as for \fBpcre_exec()\fP, and these are
+described
+.\" HTML <a href="#errorlist">
+.\" </a>
+above.
+.\"
+There are in addition the following errors that are specific to
+\fBpcre_dfa_exec()\fP:
+.sp
+  PCRE_ERROR_DFA_UITEM      (-16)
+.sp
+This return is given if \fBpcre_dfa_exec()\fP encounters an item in the pattern
+that it does not support, for instance, the use of \eC or a back reference.
+.sp
+  PCRE_ERROR_DFA_UCOND      (-17)
+.sp
+This return is given if \fBpcre_dfa_exec()\fP encounters a condition item that
+uses a back reference for the condition, or a test for recursion in a specific
+group. These are not supported.
+.sp
+  PCRE_ERROR_DFA_UMLIMIT    (-18)
+.sp
+This return is given if \fBpcre_dfa_exec()\fP is called with an \fIextra\fP
+block that contains a setting of the \fImatch_limit\fP or
+\fImatch_limit_recursion\fP fields. This is not supported (these fields are
+meaningless for DFA matching).
+.sp
+  PCRE_ERROR_DFA_WSSIZE     (-19)
+.sp
+This return is given if \fBpcre_dfa_exec()\fP runs out of space in the
+\fIworkspace\fP vector.
+.sp
+  PCRE_ERROR_DFA_RECURSE    (-20)
+.sp
+When a recursive subpattern is processed, the matching function calls itself
+recursively, using private vectors for \fIovector\fP and \fIworkspace\fP. This
+error is given if the output vector is not large enough. This should be
+extremely rare, as a vector of size 1000 is used.
+.sp
+  PCRE_ERROR_DFA_BADRESTART (-30)
+.sp
+When \fBpcre_dfa_exec()\fP is called with the \fBPCRE_DFA_RESTART\fP option,
+some plausibility checks are made on the contents of the workspace, which
+should contain data about the previous partial match. If any of these checks
+fail, this error is given.
+.
+.
+.SH "SEE ALSO"
+.rs
+.sp
+\fBpcre16\fP(3), \fBpcre32\fP(3), \fBpcrebuild\fP(3), \fBpcrecallout\fP(3),
+\fBpcrecpp(3)\fP(3), \fBpcrematching\fP(3), \fBpcrepartial\fP(3),
+\fBpcreposix\fP(3), \fBpcreprecompile\fP(3), \fBpcresample\fP(3),
+\fBpcrestack\fP(3).
+.
+.
+.SH AUTHOR
+.rs
+.sp
+.nf
+Philip Hazel
+University Computing Service
+Cambridge CB2 3QH, England.
+.fi
+.
+.
+.SH REVISION
+.rs
+.sp
+.nf
+Last updated: 09 February 2014
+Copyright (c) 1997-2014 University of Cambridge.
+.fi
diff --git a/libs/Pcre16/docs/doc/pcrebuild.3 b/libs/Pcre16/docs/doc/pcrebuild.3
new file mode 100644
index 0000000000..403f2ae32f
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcrebuild.3
@@ -0,0 +1,550 @@
+.TH PCREBUILD 3 "12 May 2013" "PCRE 8.33"
+.SH NAME
+PCRE - Perl-compatible regular expressions
+.
+.
+.SH "BUILDING PCRE"
+.rs
+.sp
+PCRE is distributed with a \fBconfigure\fP script that can be used to build the
+library in Unix-like environments using the applications known as Autotools.
+Also in the distribution are files to support building using \fBCMake\fP
+instead of \fBconfigure\fP. The text file
+.\" HTML <a href="README.txt">
+.\" </a>
+\fBREADME\fP
+.\"
+contains general information about building with Autotools (some of which is
+repeated below), and also has some comments about building on various operating
+systems. There is a lot more information about building PCRE without using
+Autotools (including information about using \fBCMake\fP and building "by
+hand") in the text file called
+.\" HTML <a href="NON-AUTOTOOLS-BUILD.txt">
+.\" </a>
+\fBNON-AUTOTOOLS-BUILD\fP.
+.\"
+You should consult this file as well as the
+.\" HTML <a href="README.txt">
+.\" </a>
+\fBREADME\fP
+.\"
+file if you are building in a non-Unix-like environment.
+.
+.
+.SH "PCRE BUILD-TIME OPTIONS"
+.rs
+.sp
+The rest of this document describes the optional features of PCRE that can be
+selected when the library is compiled. It assumes use of the \fBconfigure\fP
+script, where the optional features are selected or deselected by providing
+options to \fBconfigure\fP before running the \fBmake\fP command. However, the
+same options can be selected in both Unix-like and non-Unix-like environments
+using the GUI facility of \fBcmake-gui\fP if you are using \fBCMake\fP instead
+of \fBconfigure\fP to build PCRE.
+.P
+If you are not using Autotools or \fBCMake\fP, option selection can be done by
+editing the \fBconfig.h\fP file, or by passing parameter settings to the
+compiler, as described in
+.\" HTML <a href="NON-AUTOTOOLS-BUILD.txt">
+.\" </a>
+\fBNON-AUTOTOOLS-BUILD\fP.
+.\"
+.P
+The complete list of options for \fBconfigure\fP (which includes the standard
+ones such as the selection of the installation directory) can be obtained by
+running
+.sp
+  ./configure --help
+.sp
+The following sections include descriptions of options whose names begin with
+--enable or --disable. These settings specify changes to the defaults for the
+\fBconfigure\fP command. Because of the way that \fBconfigure\fP works,
+--enable and --disable always come in pairs, so the complementary option always
+exists as well, but as it specifies the default, it is not described.
+.
+.
+.SH "BUILDING 8-BIT, 16-BIT AND 32-BIT LIBRARIES"
+.rs
+.sp
+By default, a library called \fBlibpcre\fP is built, containing functions that
+take string arguments contained in vectors of bytes, either as single-byte
+characters, or interpreted as UTF-8 strings. You can also build a separate
+library, called \fBlibpcre16\fP, in which strings are contained in vectors of
+16-bit data units and interpreted either as single-unit characters or UTF-16
+strings, by adding
+.sp
+  --enable-pcre16
+.sp
+to the \fBconfigure\fP command. You can also build yet another separate
+library, called \fBlibpcre32\fP, in which strings are contained in vectors of
+32-bit data units and interpreted either as single-unit characters or UTF-32
+strings, by adding
+.sp
+  --enable-pcre32
+.sp
+to the \fBconfigure\fP command. If you do not want the 8-bit library, add
+.sp
+  --disable-pcre8
+.sp
+as well. At least one of the three libraries must be built. Note that the C++
+and POSIX wrappers are for the 8-bit library only, and that \fBpcregrep\fP is
+an 8-bit program. None of these are built if you select only the 16-bit or
+32-bit libraries.
+.
+.
+.SH "BUILDING SHARED AND STATIC LIBRARIES"
+.rs
+.sp
+The Autotools PCRE building process uses \fBlibtool\fP to build both shared and
+static libraries by default. You can suppress one of these by adding one of
+.sp
+  --disable-shared
+  --disable-static
+.sp
+to the \fBconfigure\fP command, as required.
+.
+.
+.SH "C++ SUPPORT"
+.rs
+.sp
+By default, if the 8-bit library is being built, the \fBconfigure\fP script
+will search for a C++ compiler and C++ header files. If it finds them, it
+automatically builds the C++ wrapper library (which supports only 8-bit
+strings). You can disable this by adding
+.sp
+  --disable-cpp
+.sp
+to the \fBconfigure\fP command.
+.
+.
+.SH "UTF-8, UTF-16 AND UTF-32 SUPPORT"
+.rs
+.sp
+To build PCRE with support for UTF Unicode character strings, add
+.sp
+  --enable-utf
+.sp
+to the \fBconfigure\fP command. This setting applies to all three libraries,
+adding support for UTF-8 to the 8-bit library, support for UTF-16 to the 16-bit
+library, and support for UTF-32 to the to the 32-bit library. There are no
+separate options for enabling UTF-8, UTF-16 and UTF-32 independently because
+that would allow ridiculous settings such as requesting UTF-16 support while
+building only the 8-bit library. It is not possible to build one library with
+UTF support and another without in the same configuration. (For backwards
+compatibility, --enable-utf8 is a synonym of --enable-utf.)
+.P
+Of itself, this setting does not make PCRE treat strings as UTF-8, UTF-16 or
+UTF-32. As well as compiling PCRE with this option, you also have have to set
+the PCRE_UTF8, PCRE_UTF16 or PCRE_UTF32 option (as appropriate) when you call
+one of the pattern compiling functions.
+.P
+If you set --enable-utf when compiling in an EBCDIC environment, PCRE expects
+its input to be either ASCII or UTF-8 (depending on the run-time option). It is
+not possible to support both EBCDIC and UTF-8 codes in the same version of the
+library. Consequently, --enable-utf and --enable-ebcdic are mutually
+exclusive.
+.
+.
+.SH "UNICODE CHARACTER PROPERTY SUPPORT"
+.rs
+.sp
+UTF support allows the libraries to process character codepoints up to 0x10ffff
+in the strings that they handle. On its own, however, it does not provide any
+facilities for accessing the properties of such characters. If you want to be
+able to use the pattern escapes \eP, \ep, and \eX, which refer to Unicode
+character properties, you must add
+.sp
+  --enable-unicode-properties
+.sp
+to the \fBconfigure\fP command. This implies UTF support, even if you have
+not explicitly requested it.
+.P
+Including Unicode property support adds around 30K of tables to the PCRE
+library. Only the general category properties such as \fILu\fP and \fINd\fP are
+supported. Details are given in the
+.\" HREF
+\fBpcrepattern\fP
+.\"
+documentation.
+.
+.
+.SH "JUST-IN-TIME COMPILER SUPPORT"
+.rs
+.sp
+Just-in-time compiler support is included in the build by specifying
+.sp
+  --enable-jit
+.sp
+This support is available only for certain hardware architectures. If this
+option is set for an unsupported architecture, a compile time error occurs.
+See the
+.\" HREF
+\fBpcrejit\fP
+.\"
+documentation for a discussion of JIT usage. When JIT support is enabled,
+pcregrep automatically makes use of it, unless you add
+.sp
+  --disable-pcregrep-jit
+.sp
+to the "configure" command.
+.
+.
+.SH "CODE VALUE OF NEWLINE"
+.rs
+.sp
+By default, PCRE interprets the linefeed (LF) character as indicating the end
+of a line. This is the normal newline character on Unix-like systems. You can
+compile PCRE to use carriage return (CR) instead, by adding
+.sp
+  --enable-newline-is-cr
+.sp
+to the \fBconfigure\fP command. There is also a --enable-newline-is-lf option,
+which explicitly specifies linefeed as the newline character.
+.sp
+Alternatively, you can specify that line endings are to be indicated by the two
+character sequence CRLF. If you want this, add
+.sp
+  --enable-newline-is-crlf
+.sp
+to the \fBconfigure\fP command. There is a fourth option, specified by
+.sp
+  --enable-newline-is-anycrlf
+.sp
+which causes PCRE to recognize any of the three sequences CR, LF, or CRLF as
+indicating a line ending. Finally, a fifth option, specified by
+.sp
+  --enable-newline-is-any
+.sp
+causes PCRE to recognize any Unicode newline sequence.
+.P
+Whatever line ending convention is selected when PCRE is built can be
+overridden when the library functions are called. At build time it is
+conventional to use the standard for your operating system.
+.
+.
+.SH "WHAT \eR MATCHES"
+.rs
+.sp
+By default, the sequence \eR in a pattern matches any Unicode newline sequence,
+whatever has been selected as the line ending sequence. If you specify
+.sp
+  --enable-bsr-anycrlf
+.sp
+the default is changed so that \eR matches only CR, LF, or CRLF. Whatever is
+selected when PCRE is built can be overridden when the library functions are
+called.
+.
+.
+.SH "POSIX MALLOC USAGE"
+.rs
+.sp
+When the 8-bit library is called through the POSIX interface (see the
+.\" HREF
+\fBpcreposix\fP
+.\"
+documentation), additional working storage is required for holding the pointers
+to capturing substrings, because PCRE requires three integers per substring,
+whereas the POSIX interface provides only two. If the number of expected
+substrings is small, the wrapper function uses space on the stack, because this
+is faster than using \fBmalloc()\fP for each call. The default threshold above
+which the stack is no longer used is 10; it can be changed by adding a setting
+such as
+.sp
+  --with-posix-malloc-threshold=20
+.sp
+to the \fBconfigure\fP command.
+.
+.
+.SH "HANDLING VERY LARGE PATTERNS"
+.rs
+.sp
+Within a compiled pattern, offset values are used to point from one part to
+another (for example, from an opening parenthesis to an alternation
+metacharacter). By default, in the 8-bit and 16-bit libraries, two-byte values
+are used for these offsets, leading to a maximum size for a compiled pattern of
+around 64K. This is sufficient to handle all but the most gigantic patterns.
+Nevertheless, some people do want to process truly enormous patterns, so it is
+possible to compile PCRE to use three-byte or four-byte offsets by adding a
+setting such as
+.sp
+  --with-link-size=3
+.sp
+to the \fBconfigure\fP command. The value given must be 2, 3, or 4. For the
+16-bit library, a value of 3 is rounded up to 4. In these libraries, using
+longer offsets slows down the operation of PCRE because it has to load
+additional data when handling them. For the 32-bit library the value is always
+4 and cannot be overridden; the value of --with-link-size is ignored.
+.
+.
+.SH "AVOIDING EXCESSIVE STACK USAGE"
+.rs
+.sp
+When matching with the \fBpcre_exec()\fP function, PCRE implements backtracking
+by making recursive calls to an internal function called \fBmatch()\fP. In
+environments where the size of the stack is limited, this can severely limit
+PCRE's operation. (The Unix environment does not usually suffer from this
+problem, but it may sometimes be necessary to increase the maximum stack size.
+There is a discussion in the
+.\" HREF
+\fBpcrestack\fP
+.\"
+documentation.) An alternative approach to recursion that uses memory from the
+heap to remember data, instead of using recursive function calls, has been
+implemented to work round the problem of limited stack size. If you want to
+build a version of PCRE that works this way, add
+.sp
+  --disable-stack-for-recursion
+.sp
+to the \fBconfigure\fP command. With this configuration, PCRE will use the
+\fBpcre_stack_malloc\fP and \fBpcre_stack_free\fP variables to call memory
+management functions. By default these point to \fBmalloc()\fP and
+\fBfree()\fP, but you can replace the pointers so that your own functions are
+used instead.
+.P
+Separate functions are provided rather than using \fBpcre_malloc\fP and
+\fBpcre_free\fP because the usage is very predictable: the block sizes
+requested are always the same, and the blocks are always freed in reverse
+order. A calling program might be able to implement optimized functions that
+perform better than \fBmalloc()\fP and \fBfree()\fP. PCRE runs noticeably more
+slowly when built in this way. This option affects only the \fBpcre_exec()\fP
+function; it is not relevant for \fBpcre_dfa_exec()\fP.
+.
+.
+.SH "LIMITING PCRE RESOURCE USAGE"
+.rs
+.sp
+Internally, PCRE has a function called \fBmatch()\fP, which it calls repeatedly
+(sometimes recursively) when matching a pattern with the \fBpcre_exec()\fP
+function. By controlling the maximum number of times this function may be
+called during a single matching operation, a limit can be placed on the
+resources used by a single call to \fBpcre_exec()\fP. The limit can be changed
+at run time, as described in the
+.\" HREF
+\fBpcreapi\fP
+.\"
+documentation. The default is 10 million, but this can be changed by adding a
+setting such as
+.sp
+  --with-match-limit=500000
+.sp
+to the \fBconfigure\fP command. This setting has no effect on the
+\fBpcre_dfa_exec()\fP matching function.
+.P
+In some environments it is desirable to limit the depth of recursive calls of
+\fBmatch()\fP more strictly than the total number of calls, in order to
+restrict the maximum amount of stack (or heap, if --disable-stack-for-recursion
+is specified) that is used. A second limit controls this; it defaults to the
+value that is set for --with-match-limit, which imposes no additional
+constraints. However, you can set a lower limit by adding, for example,
+.sp
+  --with-match-limit-recursion=10000
+.sp
+to the \fBconfigure\fP command. This value can also be overridden at run time.
+.
+.
+.SH "CREATING CHARACTER TABLES AT BUILD TIME"
+.rs
+.sp
+PCRE uses fixed tables for processing characters whose code values are less
+than 256. By default, PCRE is built with a set of tables that are distributed
+in the file \fIpcre_chartables.c.dist\fP. These tables are for ASCII codes
+only. If you add
+.sp
+  --enable-rebuild-chartables
+.sp
+to the \fBconfigure\fP command, the distributed tables are no longer used.
+Instead, a program called \fBdftables\fP is compiled and run. This outputs the
+source for new set of tables, created in the default locale of your C run-time
+system. (This method of replacing the tables does not work if you are cross
+compiling, because \fBdftables\fP is run on the local host. If you need to
+create alternative tables when cross compiling, you will have to do so "by
+hand".)
+.
+.
+.SH "USING EBCDIC CODE"
+.rs
+.sp
+PCRE assumes by default that it will run in an environment where the character
+code is ASCII (or Unicode, which is a superset of ASCII). This is the case for
+most computer operating systems. PCRE can, however, be compiled to run in an
+EBCDIC environment by adding
+.sp
+  --enable-ebcdic
+.sp
+to the \fBconfigure\fP command. This setting implies
+--enable-rebuild-chartables. You should only use it if you know that you are in
+an EBCDIC environment (for example, an IBM mainframe operating system). The
+--enable-ebcdic option is incompatible with --enable-utf.
+.P
+The EBCDIC character that corresponds to an ASCII LF is assumed to have the
+value 0x15 by default. However, in some EBCDIC environments, 0x25 is used. In
+such an environment you should use
+.sp
+  --enable-ebcdic-nl25
+.sp
+as well as, or instead of, --enable-ebcdic. The EBCDIC character for CR has the
+same value as in ASCII, namely, 0x0d. Whichever of 0x15 and 0x25 is \fInot\fP
+chosen as LF is made to correspond to the Unicode NEL character (which, in
+Unicode, is 0x85).
+.P
+The options that select newline behaviour, such as --enable-newline-is-cr,
+and equivalent run-time options, refer to these character values in an EBCDIC
+environment.
+.
+.
+.SH "PCREGREP OPTIONS FOR COMPRESSED FILE SUPPORT"
+.rs
+.sp
+By default, \fBpcregrep\fP reads all files as plain text. You can build it so
+that it recognizes files whose names end in \fB.gz\fP or \fB.bz2\fP, and reads
+them with \fBlibz\fP or \fBlibbz2\fP, respectively, by adding one or both of
+.sp
+  --enable-pcregrep-libz
+  --enable-pcregrep-libbz2
+.sp
+to the \fBconfigure\fP command. These options naturally require that the
+relevant libraries are installed on your system. Configuration will fail if
+they are not.
+.
+.
+.SH "PCREGREP BUFFER SIZE"
+.rs
+.sp
+\fBpcregrep\fP uses an internal buffer to hold a "window" on the file it is
+scanning, in order to be able to output "before" and "after" lines when it
+finds a match. The size of the buffer is controlled by a parameter whose
+default value is 20K. The buffer itself is three times this size, but because
+of the way it is used for holding "before" lines, the longest line that is
+guaranteed to be processable is the parameter size. You can change the default
+parameter value by adding, for example,
+.sp
+  --with-pcregrep-bufsize=50K
+.sp
+to the \fBconfigure\fP command. The caller of \fPpcregrep\fP can, however,
+override this value by specifying a run-time option.
+.
+.
+.SH "PCRETEST OPTION FOR LIBREADLINE SUPPORT"
+.rs
+.sp
+If you add
+.sp
+  --enable-pcretest-libreadline
+.sp
+to the \fBconfigure\fP command, \fBpcretest\fP is linked with the
+\fBlibreadline\fP library, and when its input is from a terminal, it reads it
+using the \fBreadline()\fP function. This provides line-editing and history
+facilities. Note that \fBlibreadline\fP is GPL-licensed, so if you distribute a
+binary of \fBpcretest\fP linked in this way, there may be licensing issues.
+.P
+Setting this option causes the \fB-lreadline\fP option to be added to the
+\fBpcretest\fP build. In many operating environments with a sytem-installed
+\fBlibreadline\fP this is sufficient. However, in some environments (e.g.
+if an unmodified distribution version of readline is in use), some extra
+configuration may be necessary. The INSTALL file for \fBlibreadline\fP says
+this:
+.sp
+  "Readline uses the termcap functions, but does not link with the
+  termcap or curses library itself, allowing applications which link
+  with readline the to choose an appropriate library."
+.sp
+If your environment has not been set up so that an appropriate library is
+automatically included, you may need to add something like
+.sp
+  LIBS="-ncurses"
+.sp
+immediately before the \fBconfigure\fP command.
+.
+.
+.SH "DEBUGGING WITH VALGRIND SUPPORT"
+.rs
+.sp
+By adding the
+.sp
+  --enable-valgrind
+.sp
+option to to the \fBconfigure\fP command, PCRE will use valgrind annotations
+to mark certain memory regions as unaddressable. This allows it to detect
+invalid memory accesses, and is mostly useful for debugging PCRE itself.
+.
+.
+.SH "CODE COVERAGE REPORTING"
+.rs
+.sp
+If your C compiler is gcc, you can build a version of PCRE that can generate a
+code coverage report for its test suite. To enable this, you must install
+\fBlcov\fP version 1.6 or above. Then specify
+.sp
+  --enable-coverage
+.sp
+to the \fBconfigure\fP command and build PCRE in the usual way.
+.P
+Note that using \fBccache\fP (a caching C compiler) is incompatible with code
+coverage reporting. If you have configured \fBccache\fP to run automatically
+on your system, you must set the environment variable
+.sp
+  CCACHE_DISABLE=1
+.sp
+before running \fBmake\fP to build PCRE, so that \fBccache\fP is not used.
+.P
+When --enable-coverage is used, the following addition targets are added to the
+\fIMakefile\fP:
+.sp
+  make coverage
+.sp
+This creates a fresh coverage report for the PCRE test suite. It is equivalent
+to running "make coverage-reset", "make coverage-baseline", "make check", and
+then "make coverage-report".
+.sp
+  make coverage-reset
+.sp
+This zeroes the coverage counters, but does nothing else.
+.sp
+  make coverage-baseline
+.sp
+This captures baseline coverage information.
+.sp
+  make coverage-report
+.sp
+This creates the coverage report.
+.sp
+  make coverage-clean-report
+.sp
+This removes the generated coverage report without cleaning the coverage data
+itself.
+.sp
+  make coverage-clean-data
+.sp
+This removes the captured coverage data without removing the coverage files
+created at compile time (*.gcno).
+.sp
+  make coverage-clean
+.sp
+This cleans all coverage data including the generated coverage report. For more
+information about code coverage, see the \fBgcov\fP and \fBlcov\fP
+documentation.
+.
+.
+.SH "SEE ALSO"
+.rs
+.sp
+\fBpcreapi\fP(3), \fBpcre16\fP, \fBpcre32\fP, \fBpcre_config\fP(3).
+.
+.
+.SH AUTHOR
+.rs
+.sp
+.nf
+Philip Hazel
+University Computing Service
+Cambridge CB2 3QH, England.
+.fi
+.
+.
+.SH REVISION
+.rs
+.sp
+.nf
+Last updated: 12 May 2013
+Copyright (c) 1997-2013 University of Cambridge.
+.fi
diff --git a/libs/Pcre16/docs/doc/pcrecallout.3 b/libs/Pcre16/docs/doc/pcrecallout.3
new file mode 100644
index 0000000000..8ebc995952
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcrecallout.3
@@ -0,0 +1,255 @@
+.TH PCRECALLOUT 3 "12 November 2013" "PCRE 8.34"
+.SH NAME
+PCRE - Perl-compatible regular expressions
+.SH SYNOPSIS
+.rs
+.sp
+.B #include <pcre.h>
+.PP
+.SM
+.B int (*pcre_callout)(pcre_callout_block *);
+.PP
+.B int (*pcre16_callout)(pcre16_callout_block *);
+.PP
+.B int (*pcre32_callout)(pcre32_callout_block *);
+.
+.SH DESCRIPTION
+.rs
+.sp
+PCRE provides a feature called "callout", which is a means of temporarily
+passing control to the caller of PCRE in the middle of pattern matching. The
+caller of PCRE provides an external function by putting its entry point in the
+global variable \fIpcre_callout\fP (\fIpcre16_callout\fP for the 16-bit
+library, \fIpcre32_callout\fP for the 32-bit library). By default, this
+variable contains NULL, which disables all calling out.
+.P
+Within a regular expression, (?C) indicates the points at which the external
+function is to be called. Different callout points can be identified by putting
+a number less than 256 after the letter C. The default value is zero.
+For example, this pattern has two callout points:
+.sp
+  (?C1)abc(?C2)def
+.sp
+If the PCRE_AUTO_CALLOUT option bit is set when a pattern is compiled, PCRE
+automatically inserts callouts, all with number 255, before each item in the
+pattern. For example, if PCRE_AUTO_CALLOUT is used with the pattern
+.sp
+  A(\ed{2}|--)
+.sp
+it is processed as if it were
+.sp
+(?C255)A(?C255)((?C255)\ed{2}(?C255)|(?C255)-(?C255)-(?C255))(?C255)
+.sp
+Notice that there is a callout before and after each parenthesis and
+alternation bar. If the pattern contains a conditional group whose condition is
+an assertion, an automatic callout is inserted immediately before the
+condition. Such a callout may also be inserted explicitly, for example:
+.sp
+  (?(?C9)(?=a)ab|de)
+.sp
+This applies only to assertion conditions (because they are themselves
+independent groups).
+.P
+Automatic callouts can be used for tracking the progress of pattern matching.
+The
+.\" HREF
+\fBpcretest\fP
+.\"
+program has a pattern qualifier (/C) that sets automatic callouts; when it is
+used, the output indicates how the pattern is being matched. This is useful
+information when you are trying to optimize the performance of a particular
+pattern.
+.
+.
+.SH "MISSING CALLOUTS"
+.rs
+.sp
+You should be aware that, because of optimizations in the way PCRE compiles and
+matches patterns, callouts sometimes do not happen exactly as you might expect.
+.P
+At compile time, PCRE "auto-possessifies" repeated items when it knows that
+what follows cannot be part of the repeat. For example, a+[bc] is compiled as
+if it were a++[bc]. The \fBpcretest\fP output when this pattern is anchored and
+then applied with automatic callouts to the string "aaaa" is:
+.sp
+  --->aaaa
+   +0 ^        ^
+   +1 ^        a+
+   +3 ^   ^    [bc]
+  No match
+.sp
+This indicates that when matching [bc] fails, there is no backtracking into a+
+and therefore the callouts that would be taken for the backtracks do not occur.
+You can disable the auto-possessify feature by passing PCRE_NO_AUTO_POSSESS
+to \fBpcre_compile()\fP, or starting the pattern with (*NO_AUTO_POSSESS). If
+this is done in \fBpcretest\fP (using the /O qualifier), the output changes to
+this:
+.sp
+  --->aaaa
+   +0 ^        ^
+   +1 ^        a+
+   +3 ^   ^    [bc]
+   +3 ^  ^     [bc]
+   +3 ^ ^      [bc]
+   +3 ^^       [bc]
+  No match
+.sp
+This time, when matching [bc] fails, the matcher backtracks into a+ and tries
+again, repeatedly, until a+ itself fails.
+.P
+Other optimizations that provide fast "no match" results also affect callouts.
+For example, if the pattern is
+.sp
+  ab(?C4)cd
+.sp
+PCRE knows that any matching string must contain the letter "d". If the subject
+string is "abyz", the lack of "d" means that matching doesn't ever start, and
+the callout is never reached. However, with "abyd", though the result is still
+no match, the callout is obeyed.
+.P
+If the pattern is studied, PCRE knows the minimum length of a matching string,
+and will immediately give a "no match" return without actually running a match
+if the subject is not long enough, or, for unanchored patterns, if it has
+been scanned far enough.
+.P
+You can disable these optimizations by passing the PCRE_NO_START_OPTIMIZE
+option to the matching function, or by starting the pattern with
+(*NO_START_OPT). This slows down the matching process, but does ensure that
+callouts such as the example above are obeyed.
+.
+.
+.SH "THE CALLOUT INTERFACE"
+.rs
+.sp
+During matching, when PCRE reaches a callout point, the external function
+defined by \fIpcre_callout\fP or \fIpcre[16|32]_callout\fP is called (if it is
+set). This applies to both normal and DFA matching. The only argument to the
+callout function is a pointer to a \fBpcre_callout\fP or
+\fBpcre[16|32]_callout\fP block. These structures contains the following
+fields:
+.sp
+  int           \fIversion\fP;
+  int           \fIcallout_number\fP;
+  int          *\fIoffset_vector\fP;
+  const char   *\fIsubject\fP;           (8-bit version)
+  PCRE_SPTR16   \fIsubject\fP;           (16-bit version)
+  PCRE_SPTR32   \fIsubject\fP;           (32-bit version)
+  int           \fIsubject_length\fP;
+  int           \fIstart_match\fP;
+  int           \fIcurrent_position\fP;
+  int           \fIcapture_top\fP;
+  int           \fIcapture_last\fP;
+  void         *\fIcallout_data\fP;
+  int           \fIpattern_position\fP;
+  int           \fInext_item_length\fP;
+  const unsigned char *\fImark\fP;       (8-bit version)
+  const PCRE_UCHAR16  *\fImark\fP;       (16-bit version)
+  const PCRE_UCHAR32  *\fImark\fP;       (32-bit version)
+.sp
+The \fIversion\fP field is an integer containing the version number of the
+block format. The initial version was 0; the current version is 2. The version
+number will change again in future if additional fields are added, but the
+intention is never to remove any of the existing fields.
+.P
+The \fIcallout_number\fP field contains the number of the callout, as compiled
+into the pattern (that is, the number after ?C for manual callouts, and 255 for
+automatically generated callouts).
+.P
+The \fIoffset_vector\fP field is a pointer to the vector of offsets that was
+passed by the caller to the matching function. When \fBpcre_exec()\fP or
+\fBpcre[16|32]_exec()\fP is used, the contents can be inspected, in order to
+extract substrings that have been matched so far, in the same way as for
+extracting substrings after a match has completed. For the DFA matching
+functions, this field is not useful.
+.P
+The \fIsubject\fP and \fIsubject_length\fP fields contain copies of the values
+that were passed to the matching function.
+.P
+The \fIstart_match\fP field normally contains the offset within the subject at
+which the current match attempt started. However, if the escape sequence \eK
+has been encountered, this value is changed to reflect the modified starting
+point. If the pattern is not anchored, the callout function may be called
+several times from the same point in the pattern for different starting points
+in the subject.
+.P
+The \fIcurrent_position\fP field contains the offset within the subject of the
+current match pointer.
+.P
+When the \fBpcre_exec()\fP or \fBpcre[16|32]_exec()\fP is used, the
+\fIcapture_top\fP field contains one more than the number of the highest
+numbered captured substring so far. If no substrings have been captured, the
+value of \fIcapture_top\fP is one. This is always the case when the DFA
+functions are used, because they do not support captured substrings.
+.P
+The \fIcapture_last\fP field contains the number of the most recently captured
+substring. However, when a recursion exits, the value reverts to what it was
+outside the recursion, as do the values of all captured substrings. If no
+substrings have been captured, the value of \fIcapture_last\fP is -1. This is
+always the case for the DFA matching functions.
+.P
+The \fIcallout_data\fP field contains a value that is passed to a matching
+function specifically so that it can be passed back in callouts. It is passed
+in the \fIcallout_data\fP field of a \fBpcre_extra\fP or \fBpcre[16|32]_extra\fP
+data structure. If no such data was passed, the value of \fIcallout_data\fP in
+a callout block is NULL. There is a description of the \fBpcre_extra\fP
+structure in the
+.\" HREF
+\fBpcreapi\fP
+.\"
+documentation.
+.P
+The \fIpattern_position\fP field is present from version 1 of the callout
+structure. It contains the offset to the next item to be matched in the pattern
+string.
+.P
+The \fInext_item_length\fP field is present from version 1 of the callout
+structure. It contains the length of the next item to be matched in the pattern
+string. When the callout immediately precedes an alternation bar, a closing
+parenthesis, or the end of the pattern, the length is zero. When the callout
+precedes an opening parenthesis, the length is that of the entire subpattern.
+.P
+The \fIpattern_position\fP and \fInext_item_length\fP fields are intended to
+help in distinguishing between different automatic callouts, which all have the
+same callout number. However, they are set for all callouts.
+.P
+The \fImark\fP field is present from version 2 of the callout structure. In
+callouts from \fBpcre_exec()\fP or \fBpcre[16|32]_exec()\fP it contains a
+pointer to the zero-terminated name of the most recently passed (*MARK),
+(*PRUNE), or (*THEN) item in the match, or NULL if no such items have been
+passed. Instances of (*PRUNE) or (*THEN) without a name do not obliterate a
+previous (*MARK). In callouts from the DFA matching functions this field always
+contains NULL.
+.
+.
+.SH "RETURN VALUES"
+.rs
+.sp
+The external callout function returns an integer to PCRE. If the value is zero,
+matching proceeds as normal. If the value is greater than zero, matching fails
+at the current point, but the testing of other matching possibilities goes
+ahead, just as if a lookahead assertion had failed. If the value is less than
+zero, the match is abandoned, the matching function returns the negative value.
+.P
+Negative values should normally be chosen from the set of PCRE_ERROR_xxx
+values. In particular, PCRE_ERROR_NOMATCH forces a standard "no match" failure.
+The error number PCRE_ERROR_CALLOUT is reserved for use by callout functions;
+it will never be used by PCRE itself.
+.
+.
+.SH AUTHOR
+.rs
+.sp
+.nf
+Philip Hazel
+University Computing Service
+Cambridge CB2 3QH, England.
+.fi
+.
+.
+.SH REVISION
+.rs
+.sp
+.nf
+Last updated: 12 November 2013
+Copyright (c) 1997-2013 University of Cambridge.
+.fi
diff --git a/libs/Pcre16/docs/doc/pcrecompat.3 b/libs/Pcre16/docs/doc/pcrecompat.3
new file mode 100644
index 0000000000..0cc4019823
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcrecompat.3
@@ -0,0 +1,200 @@
+.TH PCRECOMPAT 3 "10 November 2013" "PCRE 8.34"
+.SH NAME
+PCRE - Perl-compatible regular expressions
+.SH "DIFFERENCES BETWEEN PCRE AND PERL"
+.rs
+.sp
+This document describes the differences in the ways that PCRE and Perl handle
+regular expressions. The differences described here are with respect to Perl
+versions 5.10 and above.
+.P
+1. PCRE has only a subset of Perl's Unicode support. Details of what it does
+have are given in the
+.\" HREF
+\fBpcreunicode\fP
+.\"
+page.
+.P
+2. PCRE allows repeat quantifiers only on parenthesized assertions, but they do
+not mean what you might think. For example, (?!a){3} does not assert that the
+next three characters are not "a". It just asserts that the next character is
+not "a" three times (in principle: PCRE optimizes this to run the assertion
+just once). Perl allows repeat quantifiers on other assertions such as \eb, but
+these do not seem to have any use.
+.P
+3. Capturing subpatterns that occur inside negative lookahead assertions are
+counted, but their entries in the offsets vector are never set. Perl sometimes
+(but not always) sets its numerical variables from inside negative assertions.
+.P
+4. Though binary zero characters are supported in the subject string, they are
+not allowed in a pattern string because it is passed as a normal C string,
+terminated by zero. The escape sequence \e0 can be used in the pattern to
+represent a binary zero.
+.P
+5. The following Perl escape sequences are not supported: \el, \eu, \eL,
+\eU, and \eN when followed by a character name or Unicode value. (\eN on its
+own, matching a non-newline character, is supported.) In fact these are
+implemented by Perl's general string-handling and are not part of its pattern
+matching engine. If any of these are encountered by PCRE, an error is
+generated by default. However, if the PCRE_JAVASCRIPT_COMPAT option is set,
+\eU and \eu are interpreted as JavaScript interprets them.
+.P
+6. The Perl escape sequences \ep, \eP, and \eX are supported only if PCRE is
+built with Unicode character property support. The properties that can be
+tested with \ep and \eP are limited to the general category properties such as
+Lu and Nd, script names such as Greek or Han, and the derived properties Any
+and L&. PCRE does support the Cs (surrogate) property, which Perl does not; the
+Perl documentation says "Because Perl hides the need for the user to understand
+the internal representation of Unicode characters, there is no need to
+implement the somewhat messy concept of surrogates."
+.P
+7. PCRE does support the \eQ...\eE escape for quoting substrings. Characters in
+between are treated as literals. This is slightly different from Perl in that $
+and @ are also handled as literals inside the quotes. In Perl, they cause
+variable interpolation (but of course PCRE does not have variables). Note the
+following examples:
+.sp
+    Pattern            PCRE matches      Perl matches
+.sp
+.\" JOIN
+    \eQabc$xyz\eE        abc$xyz           abc followed by the
+                                           contents of $xyz
+    \eQabc\e$xyz\eE       abc\e$xyz          abc\e$xyz
+    \eQabc\eE\e$\eQxyz\eE   abc$xyz           abc$xyz
+.sp
+The \eQ...\eE sequence is recognized both inside and outside character classes.
+.P
+8. Fairly obviously, PCRE does not support the (?{code}) and (??{code})
+constructions. However, there is support for recursive patterns. This is not
+available in Perl 5.8, but it is in Perl 5.10. Also, the PCRE "callout"
+feature allows an external function to be called during pattern matching. See
+the
+.\" HREF
+\fBpcrecallout\fP
+.\"
+documentation for details.
+.P
+9. Subpatterns that are called as subroutines (whether or not recursively) are
+always treated as atomic groups in PCRE. This is like Python, but unlike Perl.
+Captured values that are set outside a subroutine call can be reference from
+inside in PCRE, but not in Perl. There is a discussion that explains these
+differences in more detail in the
+.\" HTML <a href="pcrepattern.html#recursiondifference">
+.\" </a>
+section on recursion differences from Perl
+.\"
+in the
+.\" HREF
+\fBpcrepattern\fP
+.\"
+page.
+.P
+10. If any of the backtracking control verbs are used in a subpattern that is
+called as a subroutine (whether or not recursively), their effect is confined
+to that subpattern; it does not extend to the surrounding pattern. This is not
+always the case in Perl. In particular, if (*THEN) is present in a group that
+is called as a subroutine, its action is limited to that group, even if the
+group does not contain any | characters. Note that such subpatterns are
+processed as anchored at the point where they are tested.
+.P
+11. If a pattern contains more than one backtracking control verb, the first
+one that is backtracked onto acts. For example, in the pattern
+A(*COMMIT)B(*PRUNE)C a failure in B triggers (*COMMIT), but a failure in C
+triggers (*PRUNE). Perl's behaviour is more complex; in many cases it is the
+same as PCRE, but there are examples where it differs.
+.P
+12. Most backtracking verbs in assertions have their normal actions. They are
+not confined to the assertion.
+.P
+13. There are some differences that are concerned with the settings of captured
+strings when part of a pattern is repeated. For example, matching "aba" against
+the pattern /^(a(b)?)+$/ in Perl leaves $2 unset, but in PCRE it is set to "b".
+.P
+14. PCRE's handling of duplicate subpattern numbers and duplicate subpattern
+names is not as general as Perl's. This is a consequence of the fact the PCRE
+works internally just with numbers, using an external table to translate
+between numbers and names. In particular, a pattern such as (?|(?<a>A)|(?<b)B),
+where the two capturing parentheses have the same number but different names,
+is not supported, and causes an error at compile time. If it were allowed, it
+would not be possible to distinguish which parentheses matched, because both
+names map to capturing subpattern number 1. To avoid this confusing situation,
+an error is given at compile time.
+.P
+15. Perl recognizes comments in some places that PCRE does not, for example,
+between the ( and ? at the start of a subpattern. If the /x modifier is set,
+Perl allows white space between ( and ? (though current Perls warn that this is
+deprecated) but PCRE never does, even if the PCRE_EXTENDED option is set.
+.P
+16. Perl, when in warning mode, gives warnings for character classes such as
+[A-\ed] or [a-[:digit:]]. It then treats the hyphens as literals. PCRE has no
+warning features, so it gives an error in these cases because they are almost
+certainly user mistakes.
+.P
+17. In PCRE, the upper/lower case character properties Lu and Ll are not
+affected when case-independent matching is specified. For example, \ep{Lu}
+always matches an upper case letter. I think Perl has changed in this respect;
+in the release at the time of writing (5.16), \ep{Lu} and \ep{Ll} match all
+letters, regardless of case, when case independence is specified.
+.P
+18. PCRE provides some extensions to the Perl regular expression facilities.
+Perl 5.10 includes new features that are not in earlier versions of Perl, some
+of which (such as named parentheses) have been in PCRE for some time. This list
+is with respect to Perl 5.10:
+.sp
+(a) Although lookbehind assertions in PCRE must match fixed length strings,
+each alternative branch of a lookbehind assertion can match a different length
+of string. Perl requires them all to have the same length.
+.sp
+(b) If PCRE_DOLLAR_ENDONLY is set and PCRE_MULTILINE is not set, the $
+meta-character matches only at the very end of the string.
+.sp
+(c) If PCRE_EXTRA is set, a backslash followed by a letter with no special
+meaning is faulted. Otherwise, like Perl, the backslash is quietly ignored.
+(Perl can be made to issue a warning.)
+.sp
+(d) If PCRE_UNGREEDY is set, the greediness of the repetition quantifiers is
+inverted, that is, by default they are not greedy, but if followed by a
+question mark they are.
+.sp
+(e) PCRE_ANCHORED can be used at matching time to force a pattern to be tried
+only at the first matching position in the subject string.
+.sp
+(f) The PCRE_NOTBOL, PCRE_NOTEOL, PCRE_NOTEMPTY, PCRE_NOTEMPTY_ATSTART, and
+PCRE_NO_AUTO_CAPTURE options for \fBpcre_exec()\fP have no Perl equivalents.
+.sp
+(g) The \eR escape sequence can be restricted to match only CR, LF, or CRLF
+by the PCRE_BSR_ANYCRLF option.
+.sp
+(h) The callout facility is PCRE-specific.
+.sp
+(i) The partial matching facility is PCRE-specific.
+.sp
+(j) Patterns compiled by PCRE can be saved and re-used at a later time, even on
+different hosts that have the other endianness. However, this does not apply to
+optimized data created by the just-in-time compiler.
+.sp
+(k) The alternative matching functions (\fBpcre_dfa_exec()\fP,
+\fBpcre16_dfa_exec()\fP and \fBpcre32_dfa_exec()\fP,) match in a different way
+and are not Perl-compatible.
+.sp
+(l) PCRE recognizes some special sequences such as (*CR) at the start of
+a pattern that set overall options that cannot be changed within the pattern.
+.
+.
+.SH AUTHOR
+.rs
+.sp
+.nf
+Philip Hazel
+University Computing Service
+Cambridge CB2 3QH, England.
+.fi
+.
+.
+.SH REVISION
+.rs
+.sp
+.nf
+Last updated: 10 November 2013
+Copyright (c) 1997-2013 University of Cambridge.
+.fi
diff --git a/libs/Pcre16/docs/doc/pcrecpp.3 b/libs/Pcre16/docs/doc/pcrecpp.3
new file mode 100644
index 0000000000..fbddd86ab3
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcrecpp.3
@@ -0,0 +1,348 @@
+.TH PCRECPP 3 "08 January 2012" "PCRE 8.30"
+.SH NAME
+PCRE - Perl-compatible regular expressions.
+.SH "SYNOPSIS OF C++ WRAPPER"
+.rs
+.sp
+.B #include <pcrecpp.h>
+.
+.SH DESCRIPTION
+.rs
+.sp
+The C++ wrapper for PCRE was provided by Google Inc. Some additional
+functionality was added by Giuseppe Maxia. This brief man page was constructed
+from the notes in the \fIpcrecpp.h\fP file, which should be consulted for
+further details. Note that the C++ wrapper supports only the original 8-bit
+PCRE library. There is no 16-bit or 32-bit support at present.
+.
+.
+.SH "MATCHING INTERFACE"
+.rs
+.sp
+The "FullMatch" operation checks that supplied text matches a supplied pattern
+exactly. If pointer arguments are supplied, it copies matched sub-strings that
+match sub-patterns into them.
+.sp
+  Example: successful match
+     pcrecpp::RE re("h.*o");
+     re.FullMatch("hello");
+.sp
+  Example: unsuccessful match (requires full match):
+     pcrecpp::RE re("e");
+     !re.FullMatch("hello");
+.sp
+  Example: creating a temporary RE object:
+     pcrecpp::RE("h.*o").FullMatch("hello");
+.sp
+You can pass in a "const char*" or a "string" for "text". The examples below
+tend to use a const char*. You can, as in the different examples above, store
+the RE object explicitly in a variable or use a temporary RE object. The
+examples below use one mode or the other arbitrarily. Either could correctly be
+used for any of these examples.
+.P
+You must supply extra pointer arguments to extract matched subpieces.
+.sp
+  Example: extracts "ruby" into "s" and 1234 into "i"
+     int i;
+     string s;
+     pcrecpp::RE re("(\e\ew+):(\e\ed+)");
+     re.FullMatch("ruby:1234", &s, &i);
+.sp
+  Example: does not try to extract any extra sub-patterns
+     re.FullMatch("ruby:1234", &s);
+.sp
+  Example: does not try to extract into NULL
+     re.FullMatch("ruby:1234", NULL, &i);
+.sp
+  Example: integer overflow causes failure
+     !re.FullMatch("ruby:1234567891234", NULL, &i);
+.sp
+  Example: fails because there aren't enough sub-patterns:
+     !pcrecpp::RE("\e\ew+:\e\ed+").FullMatch("ruby:1234", &s);
+.sp
+  Example: fails because string cannot be stored in integer
+     !pcrecpp::RE("(.*)").FullMatch("ruby", &i);
+.sp
+The provided pointer arguments can be pointers to any scalar numeric
+type, or one of:
+.sp
+   string        (matched piece is copied to string)
+   StringPiece   (StringPiece is mutated to point to matched piece)
+   T             (where "bool T::ParseFrom(const char*, int)" exists)
+   NULL          (the corresponding matched sub-pattern is not copied)
+.sp
+The function returns true iff all of the following conditions are satisfied:
+.sp
+  a. "text" matches "pattern" exactly;
+.sp
+  b. The number of matched sub-patterns is >= number of supplied
+     pointers;
+.sp
+  c. The "i"th argument has a suitable type for holding the
+     string captured as the "i"th sub-pattern. If you pass in
+     void * NULL for the "i"th argument, or a non-void * NULL
+     of the correct type, or pass fewer arguments than the
+     number of sub-patterns, "i"th captured sub-pattern is
+     ignored.
+.sp
+CAVEAT: An optional sub-pattern that does not exist in the matched
+string is assigned the empty string. Therefore, the following will
+return false (because the empty string is not a valid number):
+.sp
+   int number;
+   pcrecpp::RE::FullMatch("abc", "[a-z]+(\e\ed+)?", &number);
+.sp
+The matching interface supports at most 16 arguments per call.
+If you need more, consider using the more general interface
+\fBpcrecpp::RE::DoMatch\fP. See \fBpcrecpp.h\fP for the signature for
+\fBDoMatch\fP.
+.P
+NOTE: Do not use \fBno_arg\fP, which is used internally to mark the end of a
+list of optional arguments, as a placeholder for missing arguments, as this can
+lead to segfaults.
+.
+.
+.SH "QUOTING METACHARACTERS"
+.rs
+.sp
+You can use the "QuoteMeta" operation to insert backslashes before all
+potentially meaningful characters in a string. The returned string, used as a
+regular expression, will exactly match the original string.
+.sp
+  Example:
+     string quoted = RE::QuoteMeta(unquoted);
+.sp
+Note that it's legal to escape a character even if it has no special meaning in
+a regular expression -- so this function does that. (This also makes it
+identical to the perl function of the same name; see "perldoc -f quotemeta".)
+For example, "1.5-2.0?" becomes "1\e.5\e-2\e.0\e?".
+.
+.SH "PARTIAL MATCHES"
+.rs
+.sp
+You can use the "PartialMatch" operation when you want the pattern
+to match any substring of the text.
+.sp
+  Example: simple search for a string:
+     pcrecpp::RE("ell").PartialMatch("hello");
+.sp
+  Example: find first number in a string:
+     int number;
+     pcrecpp::RE re("(\e\ed+)");
+     re.PartialMatch("x*100 + 20", &number);
+     assert(number == 100);
+.
+.
+.SH "UTF-8 AND THE MATCHING INTERFACE"
+.rs
+.sp
+By default, pattern and text are plain text, one byte per character. The UTF8
+flag, passed to the constructor, causes both pattern and string to be treated
+as UTF-8 text, still a byte stream but potentially multiple bytes per
+character. In practice, the text is likelier to be UTF-8 than the pattern, but
+the match returned may depend on the UTF8 flag, so always use it when matching
+UTF8 text. For example, "." will match one byte normally but with UTF8 set may
+match up to three bytes of a multi-byte character.
+.sp
+  Example:
+     pcrecpp::RE_Options options;
+     options.set_utf8();
+     pcrecpp::RE re(utf8_pattern, options);
+     re.FullMatch(utf8_string);
+.sp
+  Example: using the convenience function UTF8():
+     pcrecpp::RE re(utf8_pattern, pcrecpp::UTF8());
+     re.FullMatch(utf8_string);
+.sp
+NOTE: The UTF8 flag is ignored if pcre was not configured with the
+      --enable-utf8 flag.
+.
+.
+.SH "PASSING MODIFIERS TO THE REGULAR EXPRESSION ENGINE"
+.rs
+.sp
+PCRE defines some modifiers to change the behavior of the regular expression
+engine. The C++ wrapper defines an auxiliary class, RE_Options, as a vehicle to
+pass such modifiers to a RE class. Currently, the following modifiers are
+supported:
+.sp
+   modifier              description               Perl corresponding
+.sp
+   PCRE_CASELESS         case insensitive match      /i
+   PCRE_MULTILINE        multiple lines match        /m
+   PCRE_DOTALL           dot matches newlines        /s
+   PCRE_DOLLAR_ENDONLY   $ matches only at end       N/A
+   PCRE_EXTRA            strict escape parsing       N/A
+   PCRE_EXTENDED         ignore white spaces         /x
+   PCRE_UTF8             handles UTF8 chars          built-in
+   PCRE_UNGREEDY         reverses * and *?           N/A
+   PCRE_NO_AUTO_CAPTURE  disables capturing parens   N/A (*)
+.sp
+(*) Both Perl and PCRE allow non capturing parentheses by means of the
+"?:" modifier within the pattern itself. e.g. (?:ab|cd) does not
+capture, while (ab|cd) does.
+.P
+For a full account on how each modifier works, please check the
+PCRE API reference page.
+.P
+For each modifier, there are two member functions whose name is made
+out of the modifier in lowercase, without the "PCRE_" prefix. For
+instance, PCRE_CASELESS is handled by
+.sp
+  bool caseless()
+.sp
+which returns true if the modifier is set, and
+.sp
+  RE_Options & set_caseless(bool)
+.sp
+which sets or unsets the modifier. Moreover, PCRE_EXTRA_MATCH_LIMIT can be
+accessed through the \fBset_match_limit()\fP and \fBmatch_limit()\fP member
+functions. Setting \fImatch_limit\fP to a non-zero value will limit the
+execution of pcre to keep it from doing bad things like blowing the stack or
+taking an eternity to return a result. A value of 5000 is good enough to stop
+stack blowup in a 2MB thread stack. Setting \fImatch_limit\fP to zero disables
+match limiting. Alternatively, you can call \fBmatch_limit_recursion()\fP
+which uses PCRE_EXTRA_MATCH_LIMIT_RECURSION to limit how much PCRE
+recurses. \fBmatch_limit()\fP limits the number of matches PCRE does;
+\fBmatch_limit_recursion()\fP limits the depth of internal recursion, and
+therefore the amount of stack that is used.
+.P
+Normally, to pass one or more modifiers to a RE class, you declare
+a \fIRE_Options\fP object, set the appropriate options, and pass this
+object to a RE constructor. Example:
+.sp
+   RE_Options opt;
+   opt.set_caseless(true);
+   if (RE("HELLO", opt).PartialMatch("hello world")) ...
+.sp
+RE_options has two constructors. The default constructor takes no arguments and
+creates a set of flags that are off by default. The optional parameter
+\fIoption_flags\fP is to facilitate transfer of legacy code from C programs.
+This lets you do
+.sp
+   RE(pattern,
+     RE_Options(PCRE_CASELESS|PCRE_MULTILINE)).PartialMatch(str);
+.sp
+However, new code is better off doing
+.sp
+   RE(pattern,
+     RE_Options().set_caseless(true).set_multiline(true))
+       .PartialMatch(str);
+.sp
+If you are going to pass one of the most used modifiers, there are some
+convenience functions that return a RE_Options class with the
+appropriate modifier already set: \fBCASELESS()\fP, \fBUTF8()\fP,
+\fBMULTILINE()\fP, \fBDOTALL\fP(), and \fBEXTENDED()\fP.
+.P
+If you need to set several options at once, and you don't want to go through
+the pains of declaring a RE_Options object and setting several options, there
+is a parallel method that give you such ability on the fly. You can concatenate
+several \fBset_xxxxx()\fP member functions, since each of them returns a
+reference to its class object. For example, to pass PCRE_CASELESS,
+PCRE_EXTENDED, and PCRE_MULTILINE to a RE with one statement, you may write:
+.sp
+   RE(" ^ xyz \e\es+ .* blah$",
+     RE_Options()
+       .set_caseless(true)
+       .set_extended(true)
+       .set_multiline(true)).PartialMatch(sometext);
+.sp
+.
+.
+.SH "SCANNING TEXT INCREMENTALLY"
+.rs
+.sp
+The "Consume" operation may be useful if you want to repeatedly
+match regular expressions at the front of a string and skip over
+them as they match. This requires use of the "StringPiece" type,
+which represents a sub-range of a real string. Like RE, StringPiece
+is defined in the pcrecpp namespace.
+.sp
+  Example: read lines of the form "var = value" from a string.
+     string contents = ...;                 // Fill string somehow
+     pcrecpp::StringPiece input(contents);  // Wrap in a StringPiece
+.sp
+     string var;
+     int value;
+     pcrecpp::RE re("(\e\ew+) = (\e\ed+)\en");
+     while (re.Consume(&input, &var, &value)) {
+       ...;
+     }
+.sp
+Each successful call to "Consume" will set "var/value", and also
+advance "input" so it points past the matched text.
+.P
+The "FindAndConsume" operation is similar to "Consume" but does not
+anchor your match at the beginning of the string. For example, you
+could extract all words from a string by repeatedly calling
+.sp
+  pcrecpp::RE("(\e\ew+)").FindAndConsume(&input, &word)
+.
+.
+.SH "PARSING HEX/OCTAL/C-RADIX NUMBERS"
+.rs
+.sp
+By default, if you pass a pointer to a numeric value, the
+corresponding text is interpreted as a base-10 number. You can
+instead wrap the pointer with a call to one of the operators Hex(),
+Octal(), or CRadix() to interpret the text in another base. The
+CRadix operator interprets C-style "0" (base-8) and "0x" (base-16)
+prefixes, but defaults to base-10.
+.sp
+  Example:
+    int a, b, c, d;
+    pcrecpp::RE re("(.*) (.*) (.*) (.*)");
+    re.FullMatch("100 40 0100 0x40",
+                 pcrecpp::Octal(&a), pcrecpp::Hex(&b),
+                 pcrecpp::CRadix(&c), pcrecpp::CRadix(&d));
+.sp
+will leave 64 in a, b, c, and d.
+.
+.
+.SH "REPLACING PARTS OF STRINGS"
+.rs
+.sp
+You can replace the first match of "pattern" in "str" with "rewrite".
+Within "rewrite", backslash-escaped digits (\e1 to \e9) can be
+used to insert text matching corresponding parenthesized group
+from the pattern. \e0 in "rewrite" refers to the entire matching
+text. For example:
+.sp
+  string s = "yabba dabba doo";
+  pcrecpp::RE("b+").Replace("d", &s);
+.sp
+will leave "s" containing "yada dabba doo". The result is true if the pattern
+matches and a replacement occurs, false otherwise.
+.P
+\fBGlobalReplace\fP is like \fBReplace\fP except that it replaces all
+occurrences of the pattern in the string with the rewrite. Replacements are
+not subject to re-matching. For example:
+.sp
+  string s = "yabba dabba doo";
+  pcrecpp::RE("b+").GlobalReplace("d", &s);
+.sp
+will leave "s" containing "yada dada doo". It returns the number of
+replacements made.
+.P
+\fBExtract\fP is like \fBReplace\fP, except that if the pattern matches,
+"rewrite" is copied into "out" (an additional argument) with substitutions.
+The non-matching portions of "text" are ignored. Returns true iff a match
+occurred and the extraction happened successfully;  if no match occurs, the
+string is left unaffected.
+.
+.
+.SH AUTHOR
+.rs
+.sp
+.nf
+The C++ wrapper was contributed by Google Inc.
+Copyright (c) 2007 Google Inc.
+.fi
+.
+.
+.SH REVISION
+.rs
+.sp
+.nf
+Last updated: 08 January 2012
+.fi
diff --git a/libs/Pcre16/docs/doc/pcredemo.3 b/libs/Pcre16/docs/doc/pcredemo.3
new file mode 100644
index 0000000000..194629b1fa
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcredemo.3
@@ -0,0 +1,424 @@
+.\" Start example.
+.de EX
+.  nr mE \\n(.f
+.  nf
+.  nh
+.  ft CW
+..
+.
+.
+.\" End example.
+.de EE
+.  ft \\n(mE
+.  fi
+.  hy \\n(HY
+..
+.
+.EX
+/*************************************************
+*           PCRE DEMONSTRATION PROGRAM           *
+*************************************************/
+
+/* This is a demonstration program to illustrate the most straightforward ways
+of calling the PCRE regular expression library from a C program. See the
+pcresample documentation for a short discussion ("man pcresample" if you have
+the PCRE man pages installed).
+
+In Unix-like environments, if PCRE is installed in your standard system
+libraries, you should be able to compile this program using this command:
+
+gcc -Wall pcredemo.c -lpcre -o pcredemo
+
+If PCRE is not installed in a standard place, it is likely to be installed with
+support for the pkg-config mechanism. If you have pkg-config, you can compile
+this program using this command:
+
+gcc -Wall pcredemo.c `pkg-config --cflags --libs libpcre` -o pcredemo
+
+If you do not have pkg-config, you may have to use this:
+
+gcc -Wall pcredemo.c -I/usr/local/include -L/usr/local/lib \e
+  -R/usr/local/lib -lpcre -o pcredemo
+
+Replace "/usr/local/include" and "/usr/local/lib" with wherever the include and
+library files for PCRE are installed on your system. Only some operating
+systems (e.g. Solaris) use the -R option.
+
+Building under Windows:
+
+If you want to statically link this program against a non-dll .a file, you must
+define PCRE_STATIC before including pcre.h, otherwise the pcre_malloc() and
+pcre_free() exported functions will be declared __declspec(dllimport), with
+unwanted results. So in this environment, uncomment the following line. */
+
+/* #define PCRE_STATIC */
+
+#include <stdio.h>
+#include <string.h>
+#include <pcre.h>
+
+#define OVECCOUNT 30    /* should be a multiple of 3 */
+
+
+int main(int argc, char **argv)
+{
+pcre *re;
+const char *error;
+char *pattern;
+char *subject;
+unsigned char *name_table;
+unsigned int option_bits;
+int erroffset;
+int find_all;
+int crlf_is_newline;
+int namecount;
+int name_entry_size;
+int ovector[OVECCOUNT];
+int subject_length;
+int rc, i;
+int utf8;
+
+
+/**************************************************************************
+* First, sort out the command line. There is only one possible option at  *
+* the moment, "-g" to request repeated matching to find all occurrences,  *
+* like Perl's /g option. We set the variable find_all to a non-zero value *
+* if the -g option is present. Apart from that, there must be exactly two *
+* arguments.                                                              *
+**************************************************************************/
+
+find_all = 0;
+for (i = 1; i < argc; i++)
+  {
+  if (strcmp(argv[i], "-g") == 0) find_all = 1;
+    else break;
+  }
+
+/* After the options, we require exactly two arguments, which are the pattern,
+and the subject string. */
+
+if (argc - i != 2)
+  {
+  printf("Two arguments required: a regex and a subject string\en");
+  return 1;
+  }
+
+pattern = argv[i];
+subject = argv[i+1];
+subject_length = (int)strlen(subject);
+
+
+/*************************************************************************
+* Now we are going to compile the regular expression pattern, and handle *
+* and errors that are detected.                                          *
+*************************************************************************/
+
+re = pcre_compile(
+  pattern,              /* the pattern */
+  0,                    /* default options */
+  &error,               /* for error message */
+  &erroffset,           /* for error offset */
+  NULL);                /* use default character tables */
+
+/* Compilation failed: print the error message and exit */
+
+if (re == NULL)
+  {
+  printf("PCRE compilation failed at offset %d: %s\en", erroffset, error);
+  return 1;
+  }
+
+
+/*************************************************************************
+* If the compilation succeeded, we call PCRE again, in order to do a     *
+* pattern match against the subject string. This does just ONE match. If *
+* further matching is needed, it will be done below.                     *
+*************************************************************************/
+
+rc = pcre_exec(
+  re,                   /* the compiled pattern */
+  NULL,                 /* no extra data - we didn't study the pattern */
+  subject,              /* the subject string */
+  subject_length,       /* the length of the subject */
+  0,                    /* start at offset 0 in the subject */
+  0,                    /* default options */
+  ovector,              /* output vector for substring information */
+  OVECCOUNT);           /* number of elements in the output vector */
+
+/* Matching failed: handle error cases */
+
+if (rc < 0)
+  {
+  switch(rc)
+    {
+    case PCRE_ERROR_NOMATCH: printf("No match\en"); break;
+    /*
+    Handle other special cases if you like
+    */
+    default: printf("Matching error %d\en", rc); break;
+    }
+  pcre_free(re);     /* Release memory used for the compiled pattern */
+  return 1;
+  }
+
+/* Match succeded */
+
+printf("\enMatch succeeded at offset %d\en", ovector[0]);
+
+
+/*************************************************************************
+* We have found the first match within the subject string. If the output *
+* vector wasn't big enough, say so. Then output any substrings that were *
+* captured.                                                              *
+*************************************************************************/
+
+/* The output vector wasn't big enough */
+
+if (rc == 0)
+  {
+  rc = OVECCOUNT/3;
+  printf("ovector only has room for %d captured substrings\en", rc - 1);
+  }
+
+/* Show substrings stored in the output vector by number. Obviously, in a real
+application you might want to do things other than print them. */
+
+for (i = 0; i < rc; i++)
+  {
+  char *substring_start = subject + ovector[2*i];
+  int substring_length = ovector[2*i+1] - ovector[2*i];
+  printf("%2d: %.*s\en", i, substring_length, substring_start);
+  }
+
+
+/**************************************************************************
+* That concludes the basic part of this demonstration program. We have    *
+* compiled a pattern, and performed a single match. The code that follows *
+* shows first how to access named substrings, and then how to code for    *
+* repeated matches on the same subject.                                   *
+**************************************************************************/
+
+/* See if there are any named substrings, and if so, show them by name. First
+we have to extract the count of named parentheses from the pattern. */
+
+(void)pcre_fullinfo(
+  re,                   /* the compiled pattern */
+  NULL,                 /* no extra data - we didn't study the pattern */
+  PCRE_INFO_NAMECOUNT,  /* number of named substrings */
+  &namecount);          /* where to put the answer */
+
+if (namecount <= 0) printf("No named substrings\en"); else
+  {
+  unsigned char *tabptr;
+  printf("Named substrings\en");
+
+  /* Before we can access the substrings, we must extract the table for
+  translating names to numbers, and the size of each entry in the table. */
+
+  (void)pcre_fullinfo(
+    re,                       /* the compiled pattern */
+    NULL,                     /* no extra data - we didn't study the pattern */
+    PCRE_INFO_NAMETABLE,      /* address of the table */
+    &name_table);             /* where to put the answer */
+
+  (void)pcre_fullinfo(
+    re,                       /* the compiled pattern */
+    NULL,                     /* no extra data - we didn't study the pattern */
+    PCRE_INFO_NAMEENTRYSIZE,  /* size of each entry in the table */
+    &name_entry_size);        /* where to put the answer */
+
+  /* Now we can scan the table and, for each entry, print the number, the name,
+  and the substring itself. */
+
+  tabptr = name_table;
+  for (i = 0; i < namecount; i++)
+    {
+    int n = (tabptr[0] << 8) | tabptr[1];
+    printf("(%d) %*s: %.*s\en", n, name_entry_size - 3, tabptr + 2,
+      ovector[2*n+1] - ovector[2*n], subject + ovector[2*n]);
+    tabptr += name_entry_size;
+    }
+  }
+
+
+/*************************************************************************
+* If the "-g" option was given on the command line, we want to continue  *
+* to search for additional matches in the subject string, in a similar   *
+* way to the /g option in Perl. This turns out to be trickier than you   *
+* might think because of the possibility of matching an empty string.    *
+* What happens is as follows:                                            *
+*                                                                        *
+* If the previous match was NOT for an empty string, we can just start   *
+* the next match at the end of the previous one.                         *
+*                                                                        *
+* If the previous match WAS for an empty string, we can't do that, as it *
+* would lead to an infinite loop. Instead, a special call of pcre_exec() *
+* is made with the PCRE_NOTEMPTY_ATSTART and PCRE_ANCHORED flags set.    *
+* The first of these tells PCRE that an empty string at the start of the *
+* subject is not a valid match; other possibilities must be tried. The   *
+* second flag restricts PCRE to one match attempt at the initial string  *
+* position. If this match succeeds, an alternative to the empty string   *
+* match has been found, and we can print it and proceed round the loop,  *
+* advancing by the length of whatever was found. If this match does not  *
+* succeed, we still stay in the loop, advancing by just one character.   *
+* In UTF-8 mode, which can be set by (*UTF8) in the pattern, this may be *
+* more than one byte.                                                    *
+*                                                                        *
+* However, there is a complication concerned with newlines. When the     *
+* newline convention is such that CRLF is a valid newline, we must       *
+* advance by two characters rather than one. The newline convention can  *
+* be set in the regex by (*CR), etc.; if not, we must find the default.  *
+*************************************************************************/
+
+if (!find_all)     /* Check for -g */
+  {
+  pcre_free(re);   /* Release the memory used for the compiled pattern */
+  return 0;        /* Finish unless -g was given */
+  }
+
+/* Before running the loop, check for UTF-8 and whether CRLF is a valid newline
+sequence. First, find the options with which the regex was compiled; extract
+the UTF-8 state, and mask off all but the newline options. */
+
+(void)pcre_fullinfo(re, NULL, PCRE_INFO_OPTIONS, &option_bits);
+utf8 = option_bits & PCRE_UTF8;
+option_bits &= PCRE_NEWLINE_CR|PCRE_NEWLINE_LF|PCRE_NEWLINE_CRLF|
+               PCRE_NEWLINE_ANY|PCRE_NEWLINE_ANYCRLF;
+
+/* If no newline options were set, find the default newline convention from the
+build configuration. */
+
+if (option_bits == 0)
+  {
+  int d;
+  (void)pcre_config(PCRE_CONFIG_NEWLINE, &d);
+  /* Note that these values are always the ASCII ones, even in
+  EBCDIC environments. CR = 13, NL = 10. */
+  option_bits = (d == 13)? PCRE_NEWLINE_CR :
+          (d == 10)? PCRE_NEWLINE_LF :
+          (d == (13<<8 | 10))? PCRE_NEWLINE_CRLF :
+          (d == -2)? PCRE_NEWLINE_ANYCRLF :
+          (d == -1)? PCRE_NEWLINE_ANY : 0;
+  }
+
+/* See if CRLF is a valid newline sequence. */
+
+crlf_is_newline =
+     option_bits == PCRE_NEWLINE_ANY ||
+     option_bits == PCRE_NEWLINE_CRLF ||
+     option_bits == PCRE_NEWLINE_ANYCRLF;
+
+/* Loop for second and subsequent matches */
+
+for (;;)
+  {
+  int options = 0;                 /* Normally no options */
+  int start_offset = ovector[1];   /* Start at end of previous match */
+
+  /* If the previous match was for an empty string, we are finished if we are
+  at the end of the subject. Otherwise, arrange to run another match at the
+  same point to see if a non-empty match can be found. */
+
+  if (ovector[0] == ovector[1])
+    {
+    if (ovector[0] == subject_length) break;
+    options = PCRE_NOTEMPTY_ATSTART | PCRE_ANCHORED;
+    }
+
+  /* Run the next matching operation */
+
+  rc = pcre_exec(
+    re,                   /* the compiled pattern */
+    NULL,                 /* no extra data - we didn't study the pattern */
+    subject,              /* the subject string */
+    subject_length,       /* the length of the subject */
+    start_offset,         /* starting offset in the subject */
+    options,              /* options */
+    ovector,              /* output vector for substring information */
+    OVECCOUNT);           /* number of elements in the output vector */
+
+  /* This time, a result of NOMATCH isn't an error. If the value in "options"
+  is zero, it just means we have found all possible matches, so the loop ends.
+  Otherwise, it means we have failed to find a non-empty-string match at a
+  point where there was a previous empty-string match. In this case, we do what
+  Perl does: advance the matching position by one character, and continue. We
+  do this by setting the "end of previous match" offset, because that is picked
+  up at the top of the loop as the point at which to start again.
+
+  There are two complications: (a) When CRLF is a valid newline sequence, and
+  the current position is just before it, advance by an extra byte. (b)
+  Otherwise we must ensure that we skip an entire UTF-8 character if we are in
+  UTF-8 mode. */
+
+  if (rc == PCRE_ERROR_NOMATCH)
+    {
+    if (options == 0) break;                    /* All matches found */
+    ovector[1] = start_offset + 1;              /* Advance one byte */
+    if (crlf_is_newline &&                      /* If CRLF is newline & */
+        start_offset < subject_length - 1 &&    /* we are at CRLF, */
+        subject[start_offset] == '\er' &&
+        subject[start_offset + 1] == '\en')
+      ovector[1] += 1;                          /* Advance by one more. */
+    else if (utf8)                              /* Otherwise, ensure we */
+      {                                         /* advance a whole UTF-8 */
+      while (ovector[1] < subject_length)       /* character. */
+        {
+        if ((subject[ovector[1]] & 0xc0) != 0x80) break;
+        ovector[1] += 1;
+        }
+      }
+    continue;    /* Go round the loop again */
+    }
+
+  /* Other matching errors are not recoverable. */
+
+  if (rc < 0)
+    {
+    printf("Matching error %d\en", rc);
+    pcre_free(re);    /* Release memory used for the compiled pattern */
+    return 1;
+    }
+
+  /* Match succeded */
+
+  printf("\enMatch succeeded again at offset %d\en", ovector[0]);
+
+  /* The match succeeded, but the output vector wasn't big enough. */
+
+  if (rc == 0)
+    {
+    rc = OVECCOUNT/3;
+    printf("ovector only has room for %d captured substrings\en", rc - 1);
+    }
+
+  /* As before, show substrings stored in the output vector by number, and then
+  also any named substrings. */
+
+  for (i = 0; i < rc; i++)
+    {
+    char *substring_start = subject + ovector[2*i];
+    int substring_length = ovector[2*i+1] - ovector[2*i];
+    printf("%2d: %.*s\en", i, substring_length, substring_start);
+    }
+
+  if (namecount <= 0) printf("No named substrings\en"); else
+    {
+    unsigned char *tabptr = name_table;
+    printf("Named substrings\en");
+    for (i = 0; i < namecount; i++)
+      {
+      int n = (tabptr[0] << 8) | tabptr[1];
+      printf("(%d) %*s: %.*s\en", n, name_entry_size - 3, tabptr + 2,
+        ovector[2*n+1] - ovector[2*n], subject + ovector[2*n]);
+      tabptr += name_entry_size;
+      }
+    }
+  }      /* End of loop to find second and subsequent matches */
+
+printf("\en");
+pcre_free(re);       /* Release memory used for the compiled pattern */
+return 0;
+}
+
+/* End of pcredemo.c */
+.EE
diff --git a/libs/Pcre16/docs/doc/pcregrep.1 b/libs/Pcre16/docs/doc/pcregrep.1
new file mode 100644
index 0000000000..988667542f
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcregrep.1
@@ -0,0 +1,683 @@
+.TH PCREGREP 1 "03 April 2014" "PCRE 8.35"
+.SH NAME
+pcregrep - a grep with Perl-compatible regular expressions.
+.SH SYNOPSIS
+.B pcregrep [options] [long options] [pattern] [path1 path2 ...]
+.
+.SH DESCRIPTION
+.rs
+.sp
+\fBpcregrep\fP searches files for character patterns, in the same way as other
+grep commands do, but it uses the PCRE regular expression library to support
+patterns that are compatible with the regular expressions of Perl 5. See
+.\" HREF
+\fBpcresyntax\fP(3)
+.\"
+for a quick-reference summary of pattern syntax, or
+.\" HREF
+\fBpcrepattern\fP(3)
+.\"
+for a full description of the syntax and semantics of the regular expressions
+that PCRE supports.
+.P
+Patterns, whether supplied on the command line or in a separate file, are given
+without delimiters. For example:
+.sp
+  pcregrep Thursday /etc/motd
+.sp
+If you attempt to use delimiters (for example, by surrounding a pattern with
+slashes, as is common in Perl scripts), they are interpreted as part of the
+pattern. Quotes can of course be used to delimit patterns on the command line
+because they are interpreted by the shell, and indeed quotes are required if a
+pattern contains white space or shell metacharacters.
+.P
+The first argument that follows any option settings is treated as the single
+pattern to be matched when neither \fB-e\fP nor \fB-f\fP is present.
+Conversely, when one or both of these options are used to specify patterns, all
+arguments are treated as path names. At least one of \fB-e\fP, \fB-f\fP, or an
+argument pattern must be provided.
+.P
+If no files are specified, \fBpcregrep\fP reads the standard input. The
+standard input can also be referenced by a name consisting of a single hyphen.
+For example:
+.sp
+  pcregrep some-pattern /file1 - /file3
+.sp
+By default, each line that matches a pattern is copied to the standard
+output, and if there is more than one file, the file name is output at the
+start of each line, followed by a colon. However, there are options that can
+change how \fBpcregrep\fP behaves. In particular, the \fB-M\fP option makes it
+possible to search for patterns that span line boundaries. What defines a line
+boundary is controlled by the \fB-N\fP (\fB--newline\fP) option.
+.P
+The amount of memory used for buffering files that are being scanned is
+controlled by a parameter that can be set by the \fB--buffer-size\fP option.
+The default value for this parameter is specified when \fBpcregrep\fP is built,
+with the default default being 20K. A block of memory three times this size is
+used (to allow for buffering "before" and "after" lines). An error occurs if a
+line overflows the buffer.
+.P
+Patterns can be no longer than 8K or BUFSIZ bytes, whichever is the greater.
+BUFSIZ is defined in \fB<stdio.h>\fP. When there is more than one pattern
+(specified by the use of \fB-e\fP and/or \fB-f\fP), each pattern is applied to
+each line in the order in which they are defined, except that all the \fB-e\fP
+patterns are tried before the \fB-f\fP patterns.
+.P
+By default, as soon as one pattern matches a line, no further patterns are
+considered. However, if \fB--colour\fP (or \fB--color\fP) is used to colour the
+matching substrings, or if \fB--only-matching\fP, \fB--file-offsets\fP, or
+\fB--line-offsets\fP is used to output only the part of the line that matched
+(either shown literally, or as an offset), scanning resumes immediately
+following the match, so that further matches on the same line can be found. If
+there are multiple patterns, they are all tried on the remainder of the line,
+but patterns that follow the one that matched are not tried on the earlier part
+of the line.
+.P
+This behaviour means that the order in which multiple patterns are specified
+can affect the output when one of the above options is used. This is no longer
+the same behaviour as GNU grep, which now manages to display earlier matches
+for later patterns (as long as there is no overlap).
+.P
+Patterns that can match an empty string are accepted, but empty string
+matches are never recognized. An example is the pattern "(super)?(man)?", in
+which all components are optional. This pattern finds all occurrences of both
+"super" and "man"; the output differs from matching with "super|man" when only
+the matching substrings are being shown.
+.P
+If the \fBLC_ALL\fP or \fBLC_CTYPE\fP environment variable is set,
+\fBpcregrep\fP uses the value to set a locale when calling the PCRE library.
+The \fB--locale\fP option can be used to override this.
+.
+.
+.SH "SUPPORT FOR COMPRESSED FILES"
+.rs
+.sp
+It is possible to compile \fBpcregrep\fP so that it uses \fBlibz\fP or
+\fBlibbz2\fP to read files whose names end in \fB.gz\fP or \fB.bz2\fP,
+respectively. You can find out whether your binary has support for one or both
+of these file types by running it with the \fB--help\fP option. If the
+appropriate support is not present, files are treated as plain text. The
+standard input is always so treated.
+.
+.
+.SH "BINARY FILES"
+.rs
+.sp
+By default, a file that contains a binary zero byte within the first 1024 bytes
+is identified as a binary file, and is processed specially. (GNU grep also
+identifies binary files in this manner.) See the \fB--binary-files\fP option
+for a means of changing the way binary files are handled.
+.
+.
+.SH OPTIONS
+.rs
+.sp
+The order in which some of the options appear can affect the output. For
+example, both the \fB-h\fP and \fB-l\fP options affect the printing of file
+names. Whichever comes later in the command line will be the one that takes
+effect. Similarly, except where noted below, if an option is given twice, the
+later setting is used. Numerical values for options may be followed by K or M,
+to signify multiplication by 1024 or 1024*1024 respectively.
+.TP 10
+\fB--\fP
+This terminates the list of options. It is useful if the next item on the
+command line starts with a hyphen but is not an option. This allows for the
+processing of patterns and filenames that start with hyphens.
+.TP
+\fB-A\fP \fInumber\fP, \fB--after-context=\fP\fInumber\fP
+Output \fInumber\fP lines of context after each matching line. If filenames
+and/or line numbers are being output, a hyphen separator is used instead of a
+colon for the context lines. A line containing "--" is output between each
+group of lines, unless they are in fact contiguous in the input file. The value
+of \fInumber\fP is expected to be relatively small. However, \fBpcregrep\fP
+guarantees to have up to 8K of following text available for context output.
+.TP
+\fB-a\fP, \fB--text\fP
+Treat binary files as text. This is equivalent to
+\fB--binary-files\fP=\fItext\fP.
+.TP
+\fB-B\fP \fInumber\fP, \fB--before-context=\fP\fInumber\fP
+Output \fInumber\fP lines of context before each matching line. If filenames
+and/or line numbers are being output, a hyphen separator is used instead of a
+colon for the context lines. A line containing "--" is output between each
+group of lines, unless they are in fact contiguous in the input file. The value
+of \fInumber\fP is expected to be relatively small. However, \fBpcregrep\fP
+guarantees to have up to 8K of preceding text available for context output.
+.TP
+\fB--binary-files=\fP\fIword\fP
+Specify how binary files are to be processed. If the word is "binary" (the
+default), pattern matching is performed on binary files, but the only output is
+"Binary file <name> matches" when a match succeeds. If the word is "text",
+which is equivalent to the \fB-a\fP or \fB--text\fP option, binary files are
+processed in the same way as any other file. In this case, when a match
+succeeds, the output may be binary garbage, which can have nasty effects if
+sent to a terminal. If the word is "without-match", which is equivalent to the
+\fB-I\fP option, binary files are not processed at all; they are assumed not to
+be of interest.
+.TP
+\fB--buffer-size=\fP\fInumber\fP
+Set the parameter that controls how much memory is used for buffering files
+that are being scanned.
+.TP
+\fB-C\fP \fInumber\fP, \fB--context=\fP\fInumber\fP
+Output \fInumber\fP lines of context both before and after each matching line.
+This is equivalent to setting both \fB-A\fP and \fB-B\fP to the same value.
+.TP
+\fB-c\fP, \fB--count\fP
+Do not output individual lines from the files that are being scanned; instead
+output the number of lines that would otherwise have been shown. If no lines
+are selected, the number zero is output. If several files are are being
+scanned, a count is output for each of them. However, if the
+\fB--files-with-matches\fP option is also used, only those files whose counts
+are greater than zero are listed. When \fB-c\fP is used, the \fB-A\fP,
+\fB-B\fP, and \fB-C\fP options are ignored.
+.TP
+\fB--colour\fP, \fB--color\fP
+If this option is given without any data, it is equivalent to "--colour=auto".
+If data is required, it must be given in the same shell item, separated by an
+equals sign.
+.TP
+\fB--colour=\fP\fIvalue\fP, \fB--color=\fP\fIvalue\fP
+This option specifies under what circumstances the parts of a line that matched
+a pattern should be coloured in the output. By default, the output is not
+coloured. The value (which is optional, see above) may be "never", "always", or
+"auto". In the latter case, colouring happens only if the standard output is
+connected to a terminal. More resources are used when colouring is enabled,
+because \fBpcregrep\fP has to search for all possible matches in a line, not
+just one, in order to colour them all.
+.sp
+The colour that is used can be specified by setting the environment variable
+PCREGREP_COLOUR or PCREGREP_COLOR. The value of this variable should be a
+string of two numbers, separated by a semicolon. They are copied directly into
+the control string for setting colour on a terminal, so it is your
+responsibility to ensure that they make sense. If neither of the environment
+variables is set, the default is "1;31", which gives red.
+.TP
+\fB-D\fP \fIaction\fP, \fB--devices=\fP\fIaction\fP
+If an input path is not a regular file or a directory, "action" specifies how
+it is to be processed. Valid values are "read" (the default) or "skip"
+(silently skip the path).
+.TP
+\fB-d\fP \fIaction\fP, \fB--directories=\fP\fIaction\fP
+If an input path is a directory, "action" specifies how it is to be processed.
+Valid values are "read" (the default in non-Windows environments, for
+compatibility with GNU grep), "recurse" (equivalent to the \fB-r\fP option), or
+"skip" (silently skip the path, the default in Windows environments). In the
+"read" case, directories are read as if they were ordinary files. In some
+operating systems the effect of reading a directory like this is an immediate
+end-of-file; in others it may provoke an error.
+.TP
+\fB-e\fP \fIpattern\fP, \fB--regex=\fP\fIpattern\fP, \fB--regexp=\fP\fIpattern\fP
+Specify a pattern to be matched. This option can be used multiple times in
+order to specify several patterns. It can also be used as a way of specifying a
+single pattern that starts with a hyphen. When \fB-e\fP is used, no argument
+pattern is taken from the command line; all arguments are treated as file
+names. There is no limit to the number of patterns. They are applied to each
+line in the order in which they are defined until one matches.
+.sp
+If \fB-f\fP is used with \fB-e\fP, the command line patterns are matched first,
+followed by the patterns from the file(s), independent of the order in which
+these options are specified. Note that multiple use of \fB-e\fP is not the same
+as a single pattern with alternatives. For example, X|Y finds the first
+character in a line that is X or Y, whereas if the two patterns are given
+separately, with X first, \fBpcregrep\fP finds X if it is present, even if it
+follows Y in the line. It finds Y only if there is no X in the line. This
+matters only if you are using \fB-o\fP or \fB--colo(u)r\fP to show the part(s)
+of the line that matched.
+.TP
+\fB--exclude\fP=\fIpattern\fP
+Files (but not directories) whose names match the pattern are skipped without
+being processed. This applies to all files, whether listed on the command line,
+obtained from \fB--file-list\fP, or by scanning a directory. The pattern is a
+PCRE regular expression, and is matched against the final component of the file
+name, not the entire path. The \fB-F\fP, \fB-w\fP, and \fB-x\fP options do not
+apply to this pattern. The option may be given any number of times in order to
+specify multiple patterns. If a file name matches both an \fB--include\fP
+and an \fB--exclude\fP pattern, it is excluded. There is no short form for this
+option.
+.TP
+\fB--exclude-from=\fP\fIfilename\fP
+Treat each non-empty line of the file as the data for an \fB--exclude\fP
+option. What constitutes a newline when reading the file is the operating
+system's default. The \fB--newline\fP option has no effect on this option. This
+option may be given more than once in order to specify a number of files to
+read.
+.TP
+\fB--exclude-dir\fP=\fIpattern\fP
+Directories whose names match the pattern are skipped without being processed,
+whatever the setting of the \fB--recursive\fP option. This applies to all
+directories, whether listed on the command line, obtained from
+\fB--file-list\fP, or by scanning a parent directory. The pattern is a PCRE
+regular expression, and is matched against the final component of the directory
+name, not the entire path. The \fB-F\fP, \fB-w\fP, and \fB-x\fP options do not
+apply to this pattern. The option may be given any number of times in order to
+specify more than one pattern. If a directory matches both \fB--include-dir\fP
+and \fB--exclude-dir\fP, it is excluded. There is no short form for this
+option.
+.TP
+\fB-F\fP, \fB--fixed-strings\fP
+Interpret each data-matching pattern as a list of fixed strings, separated by
+newlines, instead of as a regular expression. What constitutes a newline for
+this purpose is controlled by the \fB--newline\fP option. The \fB-w\fP (match
+as a word) and \fB-x\fP (match whole line) options can be used with \fB-F\fP.
+They apply to each of the fixed strings. A line is selected if any of the fixed
+strings are found in it (subject to \fB-w\fP or \fB-x\fP, if present). This
+option applies only to the patterns that are matched against the contents of
+files; it does not apply to patterns specified by any of the \fB--include\fP or
+\fB--exclude\fP options.
+.TP
+\fB-f\fP \fIfilename\fP, \fB--file=\fP\fIfilename\fP
+Read patterns from the file, one per line, and match them against
+each line of input. What constitutes a newline when reading the file is the
+operating system's default. The \fB--newline\fP option has no effect on this
+option. Trailing white space is removed from each line, and blank lines are
+ignored. An empty file contains no patterns and therefore matches nothing. See
+also the comments about multiple patterns versus a single pattern with
+alternatives in the description of \fB-e\fP above.
+.sp
+If this option is given more than once, all the specified files are
+read. A data line is output if any of the patterns match it. A filename can
+be given as "-" to refer to the standard input. When \fB-f\fP is used, patterns
+specified on the command line using \fB-e\fP may also be present; they are
+tested before the file's patterns. However, no other pattern is taken from the
+command line; all arguments are treated as the names of paths to be searched.
+.TP
+\fB--file-list\fP=\fIfilename\fP
+Read a list of files and/or directories that are to be scanned from the given
+file, one per line. Trailing white space is removed from each line, and blank
+lines are ignored. These paths are processed before any that are listed on the
+command line. The filename can be given as "-" to refer to the standard input.
+If \fB--file\fP and \fB--file-list\fP are both specified as "-", patterns are
+read first. This is useful only when the standard input is a terminal, from
+which further lines (the list of files) can be read after an end-of-file
+indication. If this option is given more than once, all the specified files are
+read.
+.TP
+\fB--file-offsets\fP
+Instead of showing lines or parts of lines that match, show each match as an
+offset from the start of the file and a length, separated by a comma. In this
+mode, no context is shown. That is, the \fB-A\fP, \fB-B\fP, and \fB-C\fP
+options are ignored. If there is more than one match in a line, each of them is
+shown separately. This option is mutually exclusive with \fB--line-offsets\fP
+and \fB--only-matching\fP.
+.TP
+\fB-H\fP, \fB--with-filename\fP
+Force the inclusion of the filename at the start of output lines when searching
+a single file. By default, the filename is not shown in this case. For matching
+lines, the filename is followed by a colon; for context lines, a hyphen
+separator is used. If a line number is also being output, it follows the file
+name.
+.TP
+\fB-h\fP, \fB--no-filename\fP
+Suppress the output filenames when searching multiple files. By default,
+filenames are shown when multiple files are searched. For matching lines, the
+filename is followed by a colon; for context lines, a hyphen separator is used.
+If a line number is also being output, it follows the file name.
+.TP
+\fB--help\fP
+Output a help message, giving brief details of the command options and file
+type support, and then exit. Anything else on the command line is
+ignored.
+.TP
+\fB-I\fP
+Treat binary files as never matching. This is equivalent to
+\fB--binary-files\fP=\fIwithout-match\fP.
+.TP
+\fB-i\fP, \fB--ignore-case\fP
+Ignore upper/lower case distinctions during comparisons.
+.TP
+\fB--include\fP=\fIpattern\fP
+If any \fB--include\fP patterns are specified, the only files that are
+processed are those that match one of the patterns (and do not match an
+\fB--exclude\fP pattern). This option does not affect directories, but it
+applies to all files, whether listed on the command line, obtained from
+\fB--file-list\fP, or by scanning a directory. The pattern is a PCRE regular
+expression, and is matched against the final component of the file name, not
+the entire path. The \fB-F\fP, \fB-w\fP, and \fB-x\fP options do not apply to
+this pattern. The option may be given any number of times. If a file name
+matches both an \fB--include\fP and an \fB--exclude\fP pattern, it is excluded.
+There is no short form for this option.
+.TP
+\fB--include-from=\fP\fIfilename\fP
+Treat each non-empty line of the file as the data for an \fB--include\fP
+option. What constitutes a newline for this purpose is the operating system's
+default. The \fB--newline\fP option has no effect on this option. This option
+may be given any number of times; all the files are read.
+.TP
+\fB--include-dir\fP=\fIpattern\fP
+If any \fB--include-dir\fP patterns are specified, the only directories that
+are processed are those that match one of the patterns (and do not match an
+\fB--exclude-dir\fP pattern). This applies to all directories, whether listed
+on the command line, obtained from \fB--file-list\fP, or by scanning a parent
+directory. The pattern is a PCRE regular expression, and is matched against the
+final component of the directory name, not the entire path. The \fB-F\fP,
+\fB-w\fP, and \fB-x\fP options do not apply to this pattern. The option may be
+given any number of times. If a directory matches both \fB--include-dir\fP and
+\fB--exclude-dir\fP, it is excluded. There is no short form for this option.
+.TP
+\fB-L\fP, \fB--files-without-match\fP
+Instead of outputting lines from the files, just output the names of the files
+that do not contain any lines that would have been output. Each file name is
+output once, on a separate line.
+.TP
+\fB-l\fP, \fB--files-with-matches\fP
+Instead of outputting lines from the files, just output the names of the files
+containing lines that would have been output. Each file name is output
+once, on a separate line. Searching normally stops as soon as a matching line
+is found in a file. However, if the \fB-c\fP (count) option is also used,
+matching continues in order to obtain the correct count, and those files that
+have at least one match are listed along with their counts. Using this option
+with \fB-c\fP is a way of suppressing the listing of files with no matches.
+.TP
+\fB--label\fP=\fIname\fP
+This option supplies a name to be used for the standard input when file names
+are being output. If not supplied, "(standard input)" is used. There is no
+short form for this option.
+.TP
+\fB--line-buffered\fP
+When this option is given, input is read and processed line by line, and the
+output is flushed after each write. By default, input is read in large chunks,
+unless \fBpcregrep\fP can determine that it is reading from a terminal (which
+is currently possible only in Unix-like environments). Output to terminal is
+normally automatically flushed by the operating system. This option can be
+useful when the input or output is attached to a pipe and you do not want
+\fBpcregrep\fP to buffer up large amounts of data. However, its use will affect
+performance, and the \fB-M\fP (multiline) option ceases to work.
+.TP
+\fB--line-offsets\fP
+Instead of showing lines or parts of lines that match, show each match as a
+line number, the offset from the start of the line, and a length. The line
+number is terminated by a colon (as usual; see the \fB-n\fP option), and the
+offset and length are separated by a comma. In this mode, no context is shown.
+That is, the \fB-A\fP, \fB-B\fP, and \fB-C\fP options are ignored. If there is
+more than one match in a line, each of them is shown separately. This option is
+mutually exclusive with \fB--file-offsets\fP and \fB--only-matching\fP.
+.TP
+\fB--locale\fP=\fIlocale-name\fP
+This option specifies a locale to be used for pattern matching. It overrides
+the value in the \fBLC_ALL\fP or \fBLC_CTYPE\fP environment variables. If no
+locale is specified, the PCRE library's default (usually the "C" locale) is
+used. There is no short form for this option.
+.TP
+\fB--match-limit\fP=\fInumber\fP
+Processing some regular expression patterns can require a very large amount of
+memory, leading in some cases to a program crash if not enough is available.
+Other patterns may take a very long time to search for all possible matching
+strings. The \fBpcre_exec()\fP function that is called by \fBpcregrep\fP to do
+the matching has two parameters that can limit the resources that it uses.
+.sp
+The \fB--match-limit\fP option provides a means of limiting resource usage
+when processing patterns that are not going to match, but which have a very
+large number of possibilities in their search trees. The classic example is a
+pattern that uses nested unlimited repeats. Internally, PCRE uses a function
+called \fBmatch()\fP which it calls repeatedly (sometimes recursively). The
+limit set by \fB--match-limit\fP is imposed on the number of times this
+function is called during a match, which has the effect of limiting the amount
+of backtracking that can take place.
+.sp
+The \fB--recursion-limit\fP option is similar to \fB--match-limit\fP, but
+instead of limiting the total number of times that \fBmatch()\fP is called, it
+limits the depth of recursive calls, which in turn limits the amount of memory
+that can be used. The recursion depth is a smaller number than the total number
+of calls, because not all calls to \fBmatch()\fP are recursive. This limit is
+of use only if it is set smaller than \fB--match-limit\fP.
+.sp
+There are no short forms for these options. The default settings are specified
+when the PCRE library is compiled, with the default default being 10 million.
+.TP
+\fB-M\fP, \fB--multiline\fP
+Allow patterns to match more than one line. When this option is given, patterns
+may usefully contain literal newline characters and internal occurrences of ^
+and $ characters. The output for a successful match may consist of more than
+one line, the last of which is the one in which the match ended. If the matched
+string ends with a newline sequence the output ends at the end of that line.
+.sp
+When this option is set, the PCRE library is called in "multiline" mode.
+There is a limit to the number of lines that can be matched, imposed by the way
+that \fBpcregrep\fP buffers the input file as it scans it. However,
+\fBpcregrep\fP ensures that at least 8K characters or the rest of the document
+(whichever is the shorter) are available for forward matching, and similarly
+the previous 8K characters (or all the previous characters, if fewer than 8K)
+are guaranteed to be available for lookbehind assertions. This option does not
+work when input is read line by line (see \fP--line-buffered\fP.)
+.TP
+\fB-N\fP \fInewline-type\fP, \fB--newline\fP=\fInewline-type\fP
+The PCRE library supports five different conventions for indicating
+the ends of lines. They are the single-character sequences CR (carriage return)
+and LF (linefeed), the two-character sequence CRLF, an "anycrlf" convention,
+which recognizes any of the preceding three types, and an "any" convention, in
+which any Unicode line ending sequence is assumed to end a line. The Unicode
+sequences are the three just mentioned, plus VT (vertical tab, U+000B), FF
+(form feed, U+000C), NEL (next line, U+0085), LS (line separator, U+2028), and
+PS (paragraph separator, U+2029).
+.sp
+When the PCRE library is built, a default line-ending sequence is specified.
+This is normally the standard sequence for the operating system. Unless
+otherwise specified by this option, \fBpcregrep\fP uses the library's default.
+The possible values for this option are CR, LF, CRLF, ANYCRLF, or ANY. This
+makes it possible to use \fBpcregrep\fP to scan files that have come from other
+environments without having to modify their line endings. If the data that is
+being scanned does not agree with the convention set by this option,
+\fBpcregrep\fP may behave in strange ways. Note that this option does not
+apply to files specified by the \fB-f\fP, \fB--exclude-from\fP, or
+\fB--include-from\fP options, which are expected to use the operating system's
+standard newline sequence.
+.TP
+\fB-n\fP, \fB--line-number\fP
+Precede each output line by its line number in the file, followed by a colon
+for matching lines or a hyphen for context lines. If the filename is also being
+output, it precedes the line number. This option is forced if
+\fB--line-offsets\fP is used.
+.TP
+\fB--no-jit\fP
+If the PCRE library is built with support for just-in-time compiling (which
+speeds up matching), \fBpcregrep\fP automatically makes use of this, unless it
+was explicitly disabled at build time. This option can be used to disable the
+use of JIT at run time. It is provided for testing and working round problems.
+It should never be needed in normal use.
+.TP
+\fB-o\fP, \fB--only-matching\fP
+Show only the part of the line that matched a pattern instead of the whole
+line. In this mode, no context is shown. That is, the \fB-A\fP, \fB-B\fP, and
+\fB-C\fP options are ignored. If there is more than one match in a line, each
+of them is shown separately. If \fB-o\fP is combined with \fB-v\fP (invert the
+sense of the match to find non-matching lines), no output is generated, but the
+return code is set appropriately. If the matched portion of the line is empty,
+nothing is output unless the file name or line number are being printed, in
+which case they are shown on an otherwise empty line. This option is mutually
+exclusive with \fB--file-offsets\fP and \fB--line-offsets\fP.
+.TP
+\fB-o\fP\fInumber\fP, \fB--only-matching\fP=\fInumber\fP
+Show only the part of the line that matched the capturing parentheses of the
+given number. Up to 32 capturing parentheses are supported, and -o0 is
+equivalent to \fB-o\fP without a number. Because these options can be given
+without an argument (see above), if an argument is present, it must be given in
+the same shell item, for example, -o3 or --only-matching=2. The comments given
+for the non-argument case above also apply to this case. If the specified
+capturing parentheses do not exist in the pattern, or were not set in the
+match, nothing is output unless the file name or line number are being printed.
+.sp
+If this option is given multiple times, multiple substrings are output, in the
+order the options are given. For example, -o3 -o1 -o3 causes the substrings
+matched by capturing parentheses 3 and 1 and then 3 again to be output. By
+default, there is no separator (but see the next option).
+.TP
+\fB--om-separator\fP=\fItext\fP
+Specify a separating string for multiple occurrences of \fB-o\fP. The default
+is an empty string. Separating strings are never coloured.
+.TP
+\fB-q\fP, \fB--quiet\fP
+Work quietly, that is, display nothing except error messages. The exit
+status indicates whether or not any matches were found.
+.TP
+\fB-r\fP, \fB--recursive\fP
+If any given path is a directory, recursively scan the files it contains,
+taking note of any \fB--include\fP and \fB--exclude\fP settings. By default, a
+directory is read as a normal file; in some operating systems this gives an
+immediate end-of-file. This option is a shorthand for setting the \fB-d\fP
+option to "recurse".
+.TP
+\fB--recursion-limit\fP=\fInumber\fP
+See \fB--match-limit\fP above.
+.TP
+\fB-s\fP, \fB--no-messages\fP
+Suppress error messages about non-existent or unreadable files. Such files are
+quietly skipped. However, the return code is still 2, even if matches were
+found in other files.
+.TP
+\fB-u\fP, \fB--utf-8\fP
+Operate in UTF-8 mode. This option is available only if PCRE has been compiled
+with UTF-8 support. All patterns (including those for any \fB--exclude\fP and
+\fB--include\fP options) and all subject lines that are scanned must be valid
+strings of UTF-8 characters.
+.TP
+\fB-V\fP, \fB--version\fP
+Write the version numbers of \fBpcregrep\fP and the PCRE library to the
+standard output and then exit. Anything else on the command line is
+ignored.
+.TP
+\fB-v\fP, \fB--invert-match\fP
+Invert the sense of the match, so that lines which do \fInot\fP match any of
+the patterns are the ones that are found.
+.TP
+\fB-w\fP, \fB--word-regex\fP, \fB--word-regexp\fP
+Force the patterns to match only whole words. This is equivalent to having \eb
+at the start and end of the pattern. This option applies only to the patterns
+that are matched against the contents of files; it does not apply to patterns
+specified by any of the \fB--include\fP or \fB--exclude\fP options.
+.TP
+\fB-x\fP, \fB--line-regex\fP, \fB--line-regexp\fP
+Force the patterns to be anchored (each must start matching at the beginning of
+a line) and in addition, require them to match entire lines. This is equivalent
+to having ^ and $ characters at the start and end of each alternative branch in
+every pattern. This option applies only to the patterns that are matched
+against the contents of files; it does not apply to patterns specified by any
+of the \fB--include\fP or \fB--exclude\fP options.
+.
+.
+.SH "ENVIRONMENT VARIABLES"
+.rs
+.sp
+The environment variables \fBLC_ALL\fP and \fBLC_CTYPE\fP are examined, in that
+order, for a locale. The first one that is set is used. This can be overridden
+by the \fB--locale\fP option. If no locale is set, the PCRE library's default
+(usually the "C" locale) is used.
+.
+.
+.SH "NEWLINES"
+.rs
+.sp
+The \fB-N\fP (\fB--newline\fP) option allows \fBpcregrep\fP to scan files with
+different newline conventions from the default. Any parts of the input files
+that are written to the standard output are copied identically, with whatever
+newline sequences they have in the input. However, the setting of this option
+does not affect the interpretation of files specified by the \fB-f\fP,
+\fB--exclude-from\fP, or \fB--include-from\fP options, which are assumed to use
+the operating system's standard newline sequence, nor does it affect the way in
+which \fBpcregrep\fP writes informational messages to the standard error and
+output streams. For these it uses the string "\en" to indicate newlines,
+relying on the C I/O library to convert this to an appropriate sequence.
+.
+.
+.SH "OPTIONS COMPATIBILITY"
+.rs
+.sp
+Many of the short and long forms of \fBpcregrep\fP's options are the same
+as in the GNU \fBgrep\fP program. Any long option of the form
+\fB--xxx-regexp\fP (GNU terminology) is also available as \fB--xxx-regex\fP
+(PCRE terminology). However, the \fB--file-list\fP, \fB--file-offsets\fP,
+\fB--include-dir\fP, \fB--line-offsets\fP, \fB--locale\fP, \fB--match-limit\fP,
+\fB-M\fP, \fB--multiline\fP, \fB-N\fP, \fB--newline\fP, \fB--om-separator\fP,
+\fB--recursion-limit\fP, \fB-u\fP, and \fB--utf-8\fP options are specific to
+\fBpcregrep\fP, as is the use of the \fB--only-matching\fP option with a
+capturing parentheses number.
+.P
+Although most of the common options work the same way, a few are different in
+\fBpcregrep\fP. For example, the \fB--include\fP option's argument is a glob
+for GNU \fBgrep\fP, but a regular expression for \fBpcregrep\fP. If both the
+\fB-c\fP and \fB-l\fP options are given, GNU grep lists only file names,
+without counts, but \fBpcregrep\fP gives the counts.
+.
+.
+.SH "OPTIONS WITH DATA"
+.rs
+.sp
+There are four different ways in which an option with data can be specified.
+If a short form option is used, the data may follow immediately, or (with one
+exception) in the next command line item. For example:
+.sp
+  -f/some/file
+  -f /some/file
+.sp
+The exception is the \fB-o\fP option, which may appear with or without data.
+Because of this, if data is present, it must follow immediately in the same
+item, for example -o3.
+.P
+If a long form option is used, the data may appear in the same command line
+item, separated by an equals character, or (with two exceptions) it may appear
+in the next command line item. For example:
+.sp
+  --file=/some/file
+  --file /some/file
+.sp
+Note, however, that if you want to supply a file name beginning with ~ as data
+in a shell command, and have the shell expand ~ to a home directory, you must
+separate the file name from the option, because the shell does not treat ~
+specially unless it is at the start of an item.
+.P
+The exceptions to the above are the \fB--colour\fP (or \fB--color\fP) and
+\fB--only-matching\fP options, for which the data is optional. If one of these
+options does have data, it must be given in the first form, using an equals
+character. Otherwise \fBpcregrep\fP will assume that it has no data.
+.
+.
+.SH "MATCHING ERRORS"
+.rs
+.sp
+It is possible to supply a regular expression that takes a very long time to
+fail to match certain lines. Such patterns normally involve nested indefinite
+repeats, for example: (a+)*\ed when matched against a line of a's with no final
+digit. The PCRE matching function has a resource limit that causes it to abort
+in these circumstances. If this happens, \fBpcregrep\fP outputs an error
+message and the line that caused the problem to the standard error stream. If
+there are more than 20 such errors, \fBpcregrep\fP gives up.
+.P
+The \fB--match-limit\fP option of \fBpcregrep\fP can be used to set the overall
+resource limit; there is a second option called \fB--recursion-limit\fP that
+sets a limit on the amount of memory (usually stack) that is used (see the
+discussion of these options above).
+.
+.
+.SH DIAGNOSTICS
+.rs
+.sp
+Exit status is 0 if any matches were found, 1 if no matches were found, and 2
+for syntax errors, overlong lines, non-existent or inaccessible files (even if
+matches were found in other files) or too many matching errors. Using the
+\fB-s\fP option to suppress error messages about inaccessible files does not
+affect the return code.
+.
+.
+.SH "SEE ALSO"
+.rs
+.sp
+\fBpcrepattern\fP(3), \fBpcresyntax\fP(3), \fBpcretest\fP(1).
+.
+.
+.SH AUTHOR
+.rs
+.sp
+.nf
+Philip Hazel
+University Computing Service
+Cambridge CB2 3QH, England.
+.fi
+.
+.
+.SH REVISION
+.rs
+.sp
+.nf
+Last updated: 03 April 2014
+Copyright (c) 1997-2014 University of Cambridge.
+.fi
diff --git a/libs/Pcre16/docs/doc/pcregrep.txt b/libs/Pcre16/docs/doc/pcregrep.txt
new file mode 100644
index 0000000000..97d9a7bd37
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcregrep.txt
@@ -0,0 +1,741 @@
+PCREGREP(1)                 General Commands Manual                PCREGREP(1)
+
+
+
+NAME
+       pcregrep - a grep with Perl-compatible regular expressions.
+
+SYNOPSIS
+       pcregrep [options] [long options] [pattern] [path1 path2 ...]
+
+
+DESCRIPTION
+
+       pcregrep  searches  files  for  character  patterns, in the same way as
+       other grep commands do, but it uses the PCRE regular expression library
+       to support patterns that are compatible with the regular expressions of
+       Perl 5. See pcresyntax(3) for a quick-reference summary of pattern syn-
+       tax,  or pcrepattern(3) for a full description of the syntax and seman-
+       tics of the regular expressions that PCRE supports.
+
+       Patterns, whether supplied on the command line or in a  separate  file,
+       are given without delimiters. For example:
+
+         pcregrep Thursday /etc/motd
+
+       If you attempt to use delimiters (for example, by surrounding a pattern
+       with slashes, as is common in Perl scripts), they  are  interpreted  as
+       part  of  the pattern. Quotes can of course be used to delimit patterns
+       on the command line because they are  interpreted  by  the  shell,  and
+       indeed  quotes  are required if a pattern contains white space or shell
+       metacharacters.
+
+       The first argument that follows any option settings is treated  as  the
+       single  pattern  to be matched when neither -e nor -f is present.  Con-
+       versely, when one or both of these options are  used  to  specify  pat-
+       terns, all arguments are treated as path names. At least one of -e, -f,
+       or an argument pattern must be provided.
+
+       If no files are specified, pcregrep reads the standard input. The stan-
+       dard  input  can  also  be  referenced by a name consisting of a single
+       hyphen.  For example:
+
+         pcregrep some-pattern /file1 - /file3
+
+       By default, each line that matches a pattern is copied to the  standard
+       output,  and if there is more than one file, the file name is output at
+       the start of each line, followed by a colon. However, there are options
+       that  can  change  how  pcregrep  behaves. In particular, the -M option
+       makes it possible to search for patterns  that  span  line  boundaries.
+       What  defines  a  line  boundary  is  controlled  by the -N (--newline)
+       option.
+
+       The amount of memory used for buffering files that are being scanned is
+       controlled  by a parameter that can be set by the --buffer-size option.
+       The default value for this parameter  is  specified  when  pcregrep  is
+       built,  with  the  default  default  being 20K. A block of memory three
+       times this size is used (to allow for buffering  "before"  and  "after"
+       lines). An error occurs if a line overflows the buffer.
+
+       Patterns  can  be  no  longer than 8K or BUFSIZ bytes, whichever is the
+       greater.  BUFSIZ is defined in <stdio.h>. When there is more  than  one
+       pattern (specified by the use of -e and/or -f), each pattern is applied
+       to each line in the order in which they are defined,  except  that  all
+       the -e patterns are tried before the -f patterns.
+
+       By  default, as soon as one pattern matches a line, no further patterns
+       are considered. However, if --colour (or --color) is used to colour the
+       matching  substrings, or if --only-matching, --file-offsets, or --line-
+       offsets is used to output only  the  part  of  the  line  that  matched
+       (either shown literally, or as an offset), scanning resumes immediately
+       following the match, so that further matches on the same  line  can  be
+       found.  If  there  are  multiple  patterns,  they  are all tried on the
+       remainder of the line, but patterns that follow the  one  that  matched
+       are not tried on the earlier part of the line.
+
+       This  behaviour  means  that  the  order in which multiple patterns are
+       specified can affect the output when one of the above options is  used.
+       This  is no longer the same behaviour as GNU grep, which now manages to
+       display earlier matches for later patterns (as  long  as  there  is  no
+       overlap).
+
+       Patterns  that can match an empty string are accepted, but empty string
+       matches   are   never   recognized.   An   example   is   the   pattern
+       "(super)?(man)?",  in  which  all components are optional. This pattern
+       finds all occurrences of both "super" and  "man";  the  output  differs
+       from  matching  with  "super|man" when only the matching substrings are
+       being shown.
+
+       If the LC_ALL or LC_CTYPE environment variable is  set,  pcregrep  uses
+       the  value to set a locale when calling the PCRE library.  The --locale
+       option can be used to override this.
+
+
+SUPPORT FOR COMPRESSED FILES
+
+       It is possible to compile pcregrep so that it uses libz  or  libbz2  to
+       read  files  whose names end in .gz or .bz2, respectively. You can find
+       out whether your binary has support for one or both of these file types
+       by running it with the --help option. If the appropriate support is not
+       present, files are treated as plain text. The standard input is  always
+       so treated.
+
+
+BINARY FILES
+
+       By  default,  a  file that contains a binary zero byte within the first
+       1024 bytes is identified as a binary file, and is processed  specially.
+       (GNU  grep  also  identifies  binary  files  in  this  manner.) See the
+       --binary-files option for a means of changing the way binary files  are
+       handled.
+
+
+OPTIONS
+
+       The  order  in  which some of the options appear can affect the output.
+       For example, both the -h and -l options affect  the  printing  of  file
+       names.  Whichever  comes later in the command line will be the one that
+       takes effect. Similarly, except where noted  below,  if  an  option  is
+       given  twice,  the  later setting is used. Numerical values for options
+       may be followed by K  or  M,  to  signify  multiplication  by  1024  or
+       1024*1024 respectively.
+
+       --        This terminates the list of options. It is useful if the next
+                 item on the command line starts with a hyphen but is  not  an
+                 option.  This allows for the processing of patterns and file-
+                 names that start with hyphens.
+
+       -A number, --after-context=number
+                 Output number lines of context after each matching  line.  If
+                 filenames and/or line numbers are being output, a hyphen sep-
+                 arator is used instead of a colon for the  context  lines.  A
+                 line  containing  "--" is output between each group of lines,
+                 unless they are in fact contiguous in  the  input  file.  The
+                 value  of number is expected to be relatively small. However,
+                 pcregrep guarantees to have up to 8K of following text avail-
+                 able for context output.
+
+       -a, --text
+                 Treat  binary  files as text. This is equivalent to --binary-
+                 files=text.
+
+       -B number, --before-context=number
+                 Output number lines of context before each matching line.  If
+                 filenames and/or line numbers are being output, a hyphen sep-
+                 arator is used instead of a colon for the  context  lines.  A
+                 line  containing  "--" is output between each group of lines,
+                 unless they are in fact contiguous in  the  input  file.  The
+                 value  of number is expected to be relatively small. However,
+                 pcregrep guarantees to have up to 8K of preceding text avail-
+                 able for context output.
+
+       --binary-files=word
+                 Specify  how binary files are to be processed. If the word is
+                 "binary" (the default),  pattern  matching  is  performed  on
+                 binary  files,  but  the  only  output is "Binary file <name>
+                 matches" when a match succeeds. If the word is "text",  which
+                 is  equivalent  to  the -a or --text option, binary files are
+                 processed in the same way as any other file.  In  this  case,
+                 when  a  match  succeeds,  the  output may be binary garbage,
+                 which can have nasty effects if sent to a  terminal.  If  the
+                 word  is  "without-match",  which  is  equivalent  to  the -I
+                 option, binary files are  not  processed  at  all;  they  are
+                 assumed not to be of interest.
+
+       --buffer-size=number
+                 Set  the  parameter that controls how much memory is used for
+                 buffering files that are being scanned.
+
+       -C number, --context=number
+                 Output number lines of context both  before  and  after  each
+                 matching  line.  This is equivalent to setting both -A and -B
+                 to the same value.
+
+       -c, --count
+                 Do not output individual lines from the files that are  being
+                 scanned; instead output the number of lines that would other-
+                 wise have been shown. If no lines are  selected,  the  number
+                 zero  is  output.  If  several files are are being scanned, a
+                 count is output for each of them. However,  if  the  --files-
+                 with-matches  option  is  also  used,  only those files whose
+                 counts are greater than zero are listed. When -c is used, the
+                 -A, -B, and -C options are ignored.
+
+       --colour, --color
+                 If this option is given without any data, it is equivalent to
+                 "--colour=auto".  If data is required, it must  be  given  in
+                 the same shell item, separated by an equals sign.
+
+       --colour=value, --color=value
+                 This option specifies under what circumstances the parts of a
+                 line that matched a pattern should be coloured in the output.
+                 By  default,  the output is not coloured. The value (which is
+                 optional, see above) may be "never", "always", or "auto".  In
+                 the  latter case, colouring happens only if the standard out-
+                 put is connected to a terminal. More resources are used  when
+                 colouring  is enabled, because pcregrep has to search for all
+                 possible matches in a line, not just one, in order to  colour
+                 them all.
+
+                 The colour that is used can be specified by setting the envi-
+                 ronment variable PCREGREP_COLOUR or PCREGREP_COLOR. The value
+                 of this variable should be a string of two numbers, separated
+                 by a semicolon. They are copied  directly  into  the  control
+                 string  for  setting  colour  on  a  terminal,  so it is your
+                 responsibility to ensure that they make sense. If neither  of
+                 the  environment  variables  is  set,  the default is "1;31",
+                 which gives red.
+
+       -D action, --devices=action
+                 If an input path is  not  a  regular  file  or  a  directory,
+                 "action"  specifies  how  it is to be processed. Valid values
+                 are "read" (the default) or "skip" (silently skip the path).
+
+       -d action, --directories=action
+                 If an input path is a directory, "action" specifies how it is
+                 to  be  processed.   Valid  values are "read" (the default in
+                 non-Windows environments, for compatibility with  GNU  grep),
+                 "recurse"  (equivalent to the -r option), or "skip" (silently
+                 skip the path, the default in Windows environments).  In  the
+                 "read"  case,  directories  are read as if they were ordinary
+                 files. In some operating systems  the  effect  of  reading  a
+                 directory like this is an immediate end-of-file; in others it
+                 may provoke an error.
+
+       -e pattern, --regex=pattern, --regexp=pattern
+                 Specify a pattern to be matched. This option can be used mul-
+                 tiple times in order to specify several patterns. It can also
+                 be used as a way of specifying a single pattern  that  starts
+                 with  a hyphen. When -e is used, no argument pattern is taken
+                 from the command line; all  arguments  are  treated  as  file
+                 names.  There is no limit to the number of patterns. They are
+                 applied to each line in the order in which they  are  defined
+                 until one matches.
+
+                 If  -f is used with -e, the command line patterns are matched
+                 first, followed by the patterns from the file(s), independent
+                 of  the order in which these options are specified. Note that
+                 multiple use of -e is not the same as a single  pattern  with
+                 alternatives. For example, X|Y finds the first character in a
+                 line that is X or Y, whereas if the two  patterns  are  given
+                 separately,  with X first, pcregrep finds X if it is present,
+                 even if it follows Y in the line. It finds Y only if there is
+                 no  X  in  the line. This matters only if you are using -o or
+                 --colo(u)r to show the part(s) of the line that matched.
+
+       --exclude=pattern
+                 Files (but not directories) whose names match the pattern are
+                 skipped  without  being processed. This applies to all files,
+                 whether listed on the command  line,  obtained  from  --file-
+                 list, or by scanning a directory. The pattern is a PCRE regu-
+                 lar expression, and is matched against the final component of
+                 the  file  name,  not  the  entire  path.  The -F, -w, and -x
+                 options do not apply to this pattern. The option may be given
+                 any number of times in order to specify multiple patterns. If
+                 a file name matches both an --include and an  --exclude  pat-
+                 tern, it is excluded. There is no short form for this option.
+
+       --exclude-from=filename
+                 Treat  each  non-empty  line  of  the file as the data for an
+                 --exclude option. What constitutes a newline when reading the
+                 file  is the operating system's default. The --newline option
+                 has no effect on this option. This option may be  given  more
+                 than once in order to specify a number of files to read.
+
+       --exclude-dir=pattern
+                 Directories whose names match the pattern are skipped without
+                 being processed, whatever  the  setting  of  the  --recursive
+                 option.  This  applies  to all directories, whether listed on
+                 the command line, obtained from --file-list, or by scanning a
+                 parent  directory.  The pattern is a PCRE regular expression,
+                 and is matched against the final component of  the  directory
+                 name,  not the entire path. The -F, -w, and -x options do not
+                 apply to this pattern. The option may be given any number  of
+                 times  in order to specify more than one pattern. If a direc-
+                 tory matches both  --include-dir  and  --exclude-dir,  it  is
+                 excluded. There is no short form for this option.
+
+       -F, --fixed-strings
+                 Interpret  each  data-matching  pattern  as  a  list of fixed
+                 strings, separated by  newlines,  instead  of  as  a  regular
+                 expression.  What  constitutes  a newline for this purpose is
+                 controlled by the --newline option. The -w (match as a  word)
+                 and  -x (match whole line) options can be used with -F.  They
+                 apply to each of the fixed strings. A line is selected if any
+                 of the fixed strings are found in it (subject to -w or -x, if
+                 present). This option applies only to the patterns  that  are
+                 matched  against  the contents of files; it does not apply to
+                 patterns specified by  any  of  the  --include  or  --exclude
+                 options.
+
+       -f filename, --file=filename
+                 Read  patterns  from  the  file, one per line, and match them
+                 against each line of input. What constitutes a  newline  when
+                 reading  the  file  is  the  operating  system's default. The
+                 --newline option has no effect on this option. Trailing white
+                 space is removed from each line, and blank lines are ignored.
+                 An empty file contains  no  patterns  and  therefore  matches
+                 nothing. See also the comments about multiple patterns versus
+                 a single pattern with alternatives in the description  of  -e
+                 above.
+
+                 If  this  option  is  given more than once, all the specified
+                 files are read. A data line is output if any of the  patterns
+                 match  it.  A  filename  can  be given as "-" to refer to the
+                 standard input. When -f is used, patterns  specified  on  the
+                 command  line  using  -e may also be present; they are tested
+                 before the file's patterns.  However,  no  other  pattern  is
+                 taken from the command line; all arguments are treated as the
+                 names of paths to be searched.
+
+       --file-list=filename
+                 Read a list of  files  and/or  directories  that  are  to  be
+                 scanned  from  the  given  file, one per line. Trailing white
+                 space is removed from each line, and blank lines are ignored.
+                 These  paths  are processed before any that are listed on the
+                 command line. The filename can be given as "-"  to  refer  to
+                 the standard input.  If --file and --file-list are both spec-
+                 ified as "-", patterns are read first. This  is  useful  only
+                 when  the  standard  input  is a terminal, from which further
+                 lines (the list of files) can be read  after  an  end-of-file
+                 indication.  If  this option is given more than once, all the
+                 specified files are read.
+
+       --file-offsets
+                 Instead of showing lines or parts of lines that  match,  show
+                 each  match  as  an  offset  from the start of the file and a
+                 length, separated by a comma. In this  mode,  no  context  is
+                 shown.  That  is,  the -A, -B, and -C options are ignored. If
+                 there is more than one match in a line, each of them is shown
+                 separately.  This  option  is mutually exclusive with --line-
+                 offsets and --only-matching.
+
+       -H, --with-filename
+                 Force the inclusion of the filename at the  start  of  output
+                 lines  when searching a single file. By default, the filename
+                 is not shown in this case. For matching lines,  the  filename
+                 is followed by a colon; for context lines, a hyphen separator
+                 is used. If a line number is also being  output,  it  follows
+                 the file name.
+
+       -h, --no-filename
+                 Suppress  the output filenames when searching multiple files.
+                 By default, filenames  are  shown  when  multiple  files  are
+                 searched.  For  matching lines, the filename is followed by a
+                 colon; for context lines, a hyphen separator is used.   If  a
+                 line number is also being output, it follows the file name.
+
+       --help    Output  a  help  message, giving brief details of the command
+                 options and file type support, and then exit.  Anything  else
+                 on the command line is ignored.
+
+       -I        Treat  binary  files as never matching. This is equivalent to
+                 --binary-files=without-match.
+
+       -i, --ignore-case
+                 Ignore upper/lower case distinctions during comparisons.
+
+       --include=pattern
+                 If any --include patterns are specified, the only files  that
+                 are  processed  are those that match one of the patterns (and
+                 do not match an --exclude  pattern).  This  option  does  not
+                 affect  directories,  but  it  applies  to all files, whether
+                 listed on the command line, obtained from --file-list, or  by
+                 scanning  a  directory. The pattern is a PCRE regular expres-
+                 sion, and is matched against the final component of the  file
+                 name,  not the entire path. The -F, -w, and -x options do not
+                 apply to this pattern. The option may be given any number  of
+                 times.  If  a  file  name  matches  both  an --include and an
+                 --exclude pattern, it is excluded.  There is  no  short  form
+                 for this option.
+
+       --include-from=filename
+                 Treat  each  non-empty  line  of  the file as the data for an
+                 --include option. What constitutes a newline for this purpose
+                 is  the  operating system's default. The --newline option has
+                 no effect on this option. This option may be given any number
+                 of times; all the files are read.
+
+       --include-dir=pattern
+                 If  any --include-dir patterns are specified, the only direc-
+                 tories that are processed are those that  match  one  of  the
+                 patterns  (and  do  not match an --exclude-dir pattern). This
+                 applies to all directories, whether  listed  on  the  command
+                 line,  obtained  from  --file-list,  or  by scanning a parent
+                 directory. The pattern is a PCRE regular expression,  and  is
+                 matched  against  the  final component of the directory name,
+                 not the entire path. The -F, -w, and -x options do not  apply
+                 to this pattern. The option may be given any number of times.
+                 If a directory matches both --include-dir and  --exclude-dir,
+                 it is excluded. There is no short form for this option.
+
+       -L, --files-without-match
+                 Instead  of  outputting lines from the files, just output the
+                 names of the files that do not contain any lines  that  would
+                 have  been  output. Each file name is output once, on a sepa-
+                 rate line.
+
+       -l, --files-with-matches
+                 Instead of outputting lines from the files, just  output  the
+                 names of the files containing lines that would have been out-
+                 put. Each file name is  output  once,  on  a  separate  line.
+                 Searching  normally stops as soon as a matching line is found
+                 in a file. However, if the -c (count) option  is  also  used,
+                 matching  continues in order to obtain the correct count, and
+                 those files that have at least one  match  are  listed  along
+                 with their counts. Using this option with -c is a way of sup-
+                 pressing the listing of files with no matches.
+
+       --label=name
+                 This option supplies a name to be used for the standard input
+                 when file names are being output. If not supplied, "(standard
+                 input)" is used. There is no short form for this option.
+
+       --line-buffered
+                 When this option is given, input is read and  processed  line
+                 by  line,  and  the  output  is  flushed after each write. By
+                 default, input is read in large chunks, unless  pcregrep  can
+                 determine  that  it is reading from a terminal (which is cur-
+                 rently possible only in Unix-like  environments).  Output  to
+                 terminal  is  normally automatically flushed by the operating
+                 system. This option can be useful when the input or output is
+                 attached  to a pipe and you do not want pcregrep to buffer up
+                 large amounts of data. However, its use will  affect  perfor-
+                 mance, and the -M (multiline) option ceases to work.
+
+       --line-offsets
+                 Instead  of  showing lines or parts of lines that match, show
+                 each match as a line number, the offset from the start of the
+                 line,  and a length. The line number is terminated by a colon
+                 (as usual; see the -n option), and the offset and length  are
+                 separated  by  a  comma.  In  this mode, no context is shown.
+                 That is, the -A, -B, and -C options are ignored. If there  is
+                 more  than  one  match in a line, each of them is shown sepa-
+                 rately. This option is mutually exclusive with --file-offsets
+                 and --only-matching.
+
+       --locale=locale-name
+                 This  option specifies a locale to be used for pattern match-
+                 ing. It overrides the value in the LC_ALL or  LC_CTYPE  envi-
+                 ronment  variables.  If  no  locale  is  specified,  the PCRE
+                 library's default (usually the "C" locale) is used. There  is
+                 no short form for this option.
+
+       --match-limit=number
+                 Processing  some  regular  expression  patterns can require a
+                 very large amount of memory, leading in some cases to a  pro-
+                 gram  crash  if  not enough is available.  Other patterns may
+                 take a very long time to search  for  all  possible  matching
+                 strings.  The pcre_exec() function that is called by pcregrep
+                 to do the matching has two  parameters  that  can  limit  the
+                 resources that it uses.
+
+                 The   --match-limit  option  provides  a  means  of  limiting
+                 resource usage when processing patterns that are not going to
+                 match, but which have a very large number of possibilities in
+                 their search trees. The classic example  is  a  pattern  that
+                 uses  nested unlimited repeats. Internally, PCRE uses a func-
+                 tion called match()  which  it  calls  repeatedly  (sometimes
+                 recursively).  The  limit  set by --match-limit is imposed on
+                 the number of times this function is called during  a  match,
+                 which  has  the effect of limiting the amount of backtracking
+                 that can take place.
+
+                 The --recursion-limit option is similar to --match-limit, but
+                 instead of limiting the total number of times that match() is
+                 called, it limits the depth of recursive calls, which in turn
+                 limits  the  amount of memory that can be used. The recursion
+                 depth is a smaller number than the  total  number  of  calls,
+                 because not all calls to match() are recursive. This limit is
+                 of use only if it is set smaller than --match-limit.
+
+                 There are no short forms for these options. The default  set-
+                 tings  are  specified when the PCRE library is compiled, with
+                 the default default being 10 million.
+
+       -M, --multiline
+                 Allow patterns to match more than one line. When this  option
+                 is given, patterns may usefully contain literal newline char-
+                 acters and internal occurrences of ^ and  $  characters.  The
+                 output  for  a  successful match may consist of more than one
+                 line, the last of which is the one in which the match  ended.
+                 If the matched string ends with a newline sequence the output
+                 ends at the end of that line.
+
+                 When this option is set, the PCRE library is called in  "mul-
+                 tiline"  mode.   There is a limit to the number of lines that
+                 can be matched, imposed by the way that pcregrep buffers  the
+                 input  file as it scans it. However, pcregrep ensures that at
+                 least 8K characters or the rest of the document (whichever is
+                 the  shorter)  are  available for forward matching, and simi-
+                 larly the previous 8K characters (or all the previous charac-
+                 ters,  if  fewer  than 8K) are guaranteed to be available for
+                 lookbehind assertions. This option does not work  when  input
+                 is read line by line (see --line-buffered.)
+
+       -N newline-type, --newline=newline-type
+                 The  PCRE  library  supports  five  different conventions for
+                 indicating the ends of lines. They are  the  single-character
+                 sequences  CR  (carriage  return) and LF (linefeed), the two-
+                 character sequence CRLF, an "anycrlf" convention, which  rec-
+                 ognizes  any  of the preceding three types, and an "any" con-
+                 vention, in which any Unicode line ending sequence is assumed
+                 to  end a line. The Unicode sequences are the three just men-
+                 tioned, plus  VT  (vertical  tab,  U+000B),  FF  (form  feed,
+                 U+000C),   NEL  (next  line,  U+0085),  LS  (line  separator,
+                 U+2028), and PS (paragraph separator, U+2029).
+
+                 When  the  PCRE  library  is  built,  a  default  line-ending
+                 sequence   is  specified.   This  is  normally  the  standard
+                 sequence for the operating system. Unless otherwise specified
+                 by  this  option,  pcregrep  uses the library's default.  The
+                 possible values for this option are CR, LF, CRLF, ANYCRLF, or
+                 ANY.  This  makes  it  possible to use pcregrep to scan files
+                 that have come from other environments without having to mod-
+                 ify  their  line  endings.  If the data that is being scanned
+                 does not agree with the convention set by this option,  pcre-
+                 grep  may  behave in strange ways. Note that this option does
+                 not apply to files specified by the  -f,  --exclude-from,  or
+                 --include-from options, which are expected to use the operat-
+                 ing system's standard newline sequence.
+
+       -n, --line-number
+                 Precede each output line by its line number in the file, fol-
+                 lowed  by  a colon for matching lines or a hyphen for context
+                 lines. If the filename is also being output, it precedes  the
+                 line number. This option is forced if --line-offsets is used.
+
+       --no-jit  If  the  PCRE  library is built with support for just-in-time
+                 compiling (which speeds up matching), pcregrep  automatically
+                 makes use of this, unless it was explicitly disabled at build
+                 time. This option can be used to disable the use  of  JIT  at
+                 run  time. It is provided for testing and working round prob-
+                 lems.  It should never be needed in normal use.
+
+       -o, --only-matching
+                 Show only the part of the line that matched a pattern instead
+                 of  the  whole  line. In this mode, no context is shown. That
+                 is, the -A, -B, and -C options are ignored. If there is  more
+                 than  one  match in a line, each of them is shown separately.
+                 If -o is combined with -v (invert the sense of the  match  to
+                 find  non-matching  lines),  no  output is generated, but the
+                 return code is set appropriately. If the matched  portion  of
+                 the  line is empty, nothing is output unless the file name or
+                 line number are being printed, in which case they  are  shown
+                 on an otherwise empty line. This option is mutually exclusive
+                 with --file-offsets and --line-offsets.
+
+       -onumber, --only-matching=number
+                 Show only the part of the line  that  matched  the  capturing
+                 parentheses of the given number. Up to 32 capturing parenthe-
+                 ses are supported, and -o0 is equivalent to -o without a num-
+                 ber.  Because  these options can be given without an argument
+                 (see above), if an argument is present, it must be  given  in
+                 the  same  shell item, for example, -o3 or --only-matching=2.
+                 The comments given for the non-argument case above also apply
+                 to  this  case. If the specified capturing parentheses do not
+                 exist in the pattern, or were not set in the  match,  nothing
+                 is  output  unless  the  file  name  or line number are being
+                 printed.
+
+                 If this option is given multiple times,  multiple  substrings
+                 are  output, in the order the options are given. For example,
+                 -o3 -o1 -o3 causes the substrings matched by capturing paren-
+                 theses  3  and  1  and then 3 again to be output. By default,
+                 there is no separator (but see the next option).
+
+       --om-separator=text
+                 Specify a separating string for multiple occurrences  of  -o.
+                 The  default is an empty string. Separating strings are never
+                 coloured.
+
+       -q, --quiet
+                 Work quietly, that is, display nothing except error messages.
+                 The  exit  status  indicates  whether or not any matches were
+                 found.
+
+       -r, --recursive
+                 If any given path is a directory, recursively scan the  files
+                 it  contains, taking note of any --include and --exclude set-
+                 tings. By default, a directory is read as a normal  file;  in
+                 some  operating  systems this gives an immediate end-of-file.
+                 This option is a shorthand  for  setting  the  -d  option  to
+                 "recurse".
+
+       --recursion-limit=number
+                 See --match-limit above.
+
+       -s, --no-messages
+                 Suppress  error  messages  about  non-existent  or unreadable
+                 files. Such files are quietly skipped.  However,  the  return
+                 code is still 2, even if matches were found in other files.
+
+       -u, --utf-8
+                 Operate  in UTF-8 mode. This option is available only if PCRE
+                 has been compiled with UTF-8 support. All patterns (including
+                 those  for  any --exclude and --include options) and all sub-
+                 ject lines that are scanned must be valid  strings  of  UTF-8
+                 characters.
+
+       -V, --version
+                 Write the version numbers of pcregrep and the PCRE library to
+                 the standard output and then exit. Anything else on the  com-
+                 mand line is ignored.
+
+       -v, --invert-match
+                 Invert  the  sense  of  the match, so that lines which do not
+                 match any of the patterns are the ones that are found.
+
+       -w, --word-regex, --word-regexp
+                 Force the patterns to match only whole words. This is equiva-
+                 lent  to  having \b at the start and end of the pattern. This
+                 option applies only to the patterns that are matched  against
+                 the  contents  of files; it does not apply to patterns speci-
+                 fied by any of the --include or --exclude options.
+
+       -x, --line-regex, --line-regexp
+                 Force the patterns to be anchored (each must  start  matching
+                 at  the beginning of a line) and in addition, require them to
+                 match entire lines. This is equivalent  to  having  ^  and  $
+                 characters at the start and end of each alternative branch in
+                 every pattern. This option applies only to the patterns  that
+                 are  matched against the contents of files; it does not apply
+                 to patterns specified by any of the  --include  or  --exclude
+                 options.
+
+
+ENVIRONMENT VARIABLES
+
+       The  environment  variables  LC_ALL  and LC_CTYPE are examined, in that
+       order, for a locale. The first one that is set is  used.  This  can  be
+       overridden  by  the  --locale  option.  If  no  locale is set, the PCRE
+       library's default (usually the "C" locale) is used.
+
+
+NEWLINES
+
+       The -N (--newline) option allows pcregrep to scan files with  different
+       newline conventions from the default. Any parts of the input files that
+       are written to the standard output are copied identically,  with  what-
+       ever  newline sequences they have in the input. However, the setting of
+       this option does not affect the interpretation of  files  specified  by
+       the -f, --exclude-from, or --include-from options, which are assumed to
+       use the operating system's  standard  newline  sequence,  nor  does  it
+       affect  the  way in which pcregrep writes informational messages to the
+       standard error and output streams. For these it uses the string "\n" to
+       indicate  newlines,  relying on the C I/O library to convert this to an
+       appropriate sequence.
+
+
+OPTIONS COMPATIBILITY
+
+       Many of the short and long forms of pcregrep's options are the same  as
+       in  the GNU grep program. Any long option of the form --xxx-regexp (GNU
+       terminology) is also available as --xxx-regex (PCRE terminology).  How-
+       ever,  the  --file-list, --file-offsets, --include-dir, --line-offsets,
+       --locale, --match-limit, -M, --multiline, -N,  --newline,  --om-separa-
+       tor,  --recursion-limit,  -u, and --utf-8 options are specific to pcre-
+       grep, as is the use of the  --only-matching  option  with  a  capturing
+       parentheses number.
+
+       Although  most  of the common options work the same way, a few are dif-
+       ferent in pcregrep. For example, the --include option's argument  is  a
+       glob  for  GNU grep, but a regular expression for pcregrep. If both the
+       -c and -l options are given, GNU grep lists only  file  names,  without
+       counts, but pcregrep gives the counts.
+
+
+OPTIONS WITH DATA
+
+       There are four different ways in which an option with data can be spec-
+       ified.  If a short form option is used, the  data  may  follow  immedi-
+       ately, or (with one exception) in the next command line item. For exam-
+       ple:
+
+         -f/some/file
+         -f /some/file
+
+       The exception is the -o option, which may appear with or without  data.
+       Because  of this, if data is present, it must follow immediately in the
+       same item, for example -o3.
+
+       If a long form option is used, the data may appear in the same  command
+       line  item,  separated by an equals character, or (with two exceptions)
+       it may appear in the next command line item. For example:
+
+         --file=/some/file
+         --file /some/file
+
+       Note, however, that if you want to supply a file name beginning with  ~
+       as  data  in  a  shell  command,  and have the shell expand ~ to a home
+       directory, you must separate the file name from the option, because the
+       shell does not treat ~ specially unless it is at the start of an item.
+
+       The  exceptions  to the above are the --colour (or --color) and --only-
+       matching options, for which the data  is  optional.  If  one  of  these
+       options  does  have  data, it must be given in the first form, using an
+       equals character. Otherwise pcregrep will assume that it has no data.
+
+
+MATCHING ERRORS
+
+       It is possible to supply a regular expression that takes  a  very  long
+       time  to  fail  to  match certain lines. Such patterns normally involve
+       nested indefinite repeats, for example: (a+)*\d when matched against  a
+       line  of  a's  with  no  final  digit. The PCRE matching function has a
+       resource limit that causes it to abort in these circumstances. If  this
+       happens, pcregrep outputs an error message and the line that caused the
+       problem to the standard error stream. If there are more  than  20  such
+       errors, pcregrep gives up.
+
+       The  --match-limit  option  of  pcregrep can be used to set the overall
+       resource limit; there is a second option called --recursion-limit  that
+       sets  a limit on the amount of memory (usually stack) that is used (see
+       the discussion of these options above).
+
+
+DIAGNOSTICS
+
+       Exit status is 0 if any matches were found, 1 if no matches were found,
+       and  2  for syntax errors, overlong lines, non-existent or inaccessible
+       files (even if matches were found in other files) or too many  matching
+       errors. Using the -s option to suppress error messages about inaccessi-
+       ble files does not affect the return code.
+
+
+SEE ALSO
+
+       pcrepattern(3), pcresyntax(3), pcretest(1).
+
+
+AUTHOR
+
+       Philip Hazel
+       University Computing Service
+       Cambridge CB2 3QH, England.
+
+
+REVISION
+
+       Last updated: 03 April 2014
+       Copyright (c) 1997-2014 University of Cambridge.
diff --git a/libs/Pcre16/docs/doc/pcrejit.3 b/libs/Pcre16/docs/doc/pcrejit.3
new file mode 100644
index 0000000000..341403f7c8
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcrejit.3
@@ -0,0 +1,431 @@
+.TH PCREJIT 3 "17 March 2013" "PCRE 8.33"
+.SH NAME
+PCRE - Perl-compatible regular expressions
+.SH "PCRE JUST-IN-TIME COMPILER SUPPORT"
+.rs
+.sp
+Just-in-time compiling is a heavyweight optimization that can greatly speed up
+pattern matching. However, it comes at the cost of extra processing before the
+match is performed. Therefore, it is of most benefit when the same pattern is
+going to be matched many times. This does not necessarily mean many calls of a
+matching function; if the pattern is not anchored, matching attempts may take
+place many times at various positions in the subject, even for a single call.
+Therefore, if the subject string is very long, it may still pay to use JIT for
+one-off matches.
+.P
+JIT support applies only to the traditional Perl-compatible matching function.
+It does not apply when the DFA matching function is being used. The code for
+this support was written by Zoltan Herczeg.
+.
+.
+.SH "8-BIT, 16-BIT AND 32-BIT SUPPORT"
+.rs
+.sp
+JIT support is available for all of the 8-bit, 16-bit and 32-bit PCRE
+libraries. To keep this documentation simple, only the 8-bit interface is
+described in what follows. If you are using the 16-bit library, substitute the
+16-bit functions and 16-bit structures (for example, \fIpcre16_jit_stack\fP
+instead of \fIpcre_jit_stack\fP). If you are using the 32-bit library,
+substitute the 32-bit functions and 32-bit structures (for example,
+\fIpcre32_jit_stack\fP instead of \fIpcre_jit_stack\fP).
+.
+.
+.SH "AVAILABILITY OF JIT SUPPORT"
+.rs
+.sp
+JIT support is an optional feature of PCRE. The "configure" option --enable-jit
+(or equivalent CMake option) must be set when PCRE is built if you want to use
+JIT. The support is limited to the following hardware platforms:
+.sp
+  ARM v5, v7, and Thumb2
+  Intel x86 32-bit and 64-bit
+  MIPS 32-bit
+  Power PC 32-bit and 64-bit
+  SPARC 32-bit (experimental)
+.sp
+If --enable-jit is set on an unsupported platform, compilation fails.
+.P
+A program that is linked with PCRE 8.20 or later can tell if JIT support is
+available by calling \fBpcre_config()\fP with the PCRE_CONFIG_JIT option. The
+result is 1 when JIT is available, and 0 otherwise. However, a simple program
+does not need to check this in order to use JIT. The normal API is implemented
+in a way that falls back to the interpretive code if JIT is not available. For
+programs that need the best possible performance, there is also a "fast path"
+API that is JIT-specific.
+.P
+If your program may sometimes be linked with versions of PCRE that are older
+than 8.20, but you want to use JIT when it is available, you can test
+the values of PCRE_MAJOR and PCRE_MINOR, or the existence of a JIT macro such
+as PCRE_CONFIG_JIT, for compile-time control of your code.
+.
+.
+.SH "SIMPLE USE OF JIT"
+.rs
+.sp
+You have to do two things to make use of the JIT support in the simplest way:
+.sp
+  (1) Call \fBpcre_study()\fP with the PCRE_STUDY_JIT_COMPILE option for
+      each compiled pattern, and pass the resulting \fBpcre_extra\fP block to
+      \fBpcre_exec()\fP.
+.sp
+  (2) Use \fBpcre_free_study()\fP to free the \fBpcre_extra\fP block when it is
+      no longer needed, instead of just freeing it yourself. This ensures that
+      any JIT data is also freed.
+.sp
+For a program that may be linked with pre-8.20 versions of PCRE, you can insert
+.sp
+  #ifndef PCRE_STUDY_JIT_COMPILE
+  #define PCRE_STUDY_JIT_COMPILE 0
+  #endif
+.sp
+so that no option is passed to \fBpcre_study()\fP, and then use something like
+this to free the study data:
+.sp
+  #ifdef PCRE_CONFIG_JIT
+      pcre_free_study(study_ptr);
+  #else
+      pcre_free(study_ptr);
+  #endif
+.sp
+PCRE_STUDY_JIT_COMPILE requests the JIT compiler to generate code for complete
+matches. If you want to run partial matches using the PCRE_PARTIAL_HARD or
+PCRE_PARTIAL_SOFT options of \fBpcre_exec()\fP, you should set one or both of
+the following options in addition to, or instead of, PCRE_STUDY_JIT_COMPILE
+when you call \fBpcre_study()\fP:
+.sp
+  PCRE_STUDY_JIT_PARTIAL_HARD_COMPILE
+  PCRE_STUDY_JIT_PARTIAL_SOFT_COMPILE
+.sp
+The JIT compiler generates different optimized code for each of the three
+modes (normal, soft partial, hard partial). When \fBpcre_exec()\fP is called,
+the appropriate code is run if it is available. Otherwise, the pattern is
+matched using interpretive code.
+.P
+In some circumstances you may need to call additional functions. These are
+described in the section entitled
+.\" HTML <a href="#stackcontrol">
+.\" </a>
+"Controlling the JIT stack"
+.\"
+below.
+.P
+If JIT support is not available, PCRE_STUDY_JIT_COMPILE etc. are ignored, and
+no JIT data is created. Otherwise, the compiled pattern is passed to the JIT
+compiler, which turns it into machine code that executes much faster than the
+normal interpretive code. When \fBpcre_exec()\fP is passed a \fBpcre_extra\fP
+block containing a pointer to JIT code of the appropriate mode (normal or
+hard/soft partial), it obeys that code instead of running the interpreter. The
+result is identical, but the compiled JIT code runs much faster.
+.P
+There are some \fBpcre_exec()\fP options that are not supported for JIT
+execution. There are also some pattern items that JIT cannot handle. Details
+are given below. In both cases, execution automatically falls back to the
+interpretive code. If you want to know whether JIT was actually used for a
+particular match, you should arrange for a JIT callback function to be set up
+as described in the section entitled
+.\" HTML <a href="#stackcontrol">
+.\" </a>
+"Controlling the JIT stack"
+.\"
+below, even if you do not need to supply a non-default JIT stack. Such a
+callback function is called whenever JIT code is about to be obeyed. If the
+execution options are not right for JIT execution, the callback function is not
+obeyed.
+.P
+If the JIT compiler finds an unsupported item, no JIT data is generated. You
+can find out if JIT execution is available after studying a pattern by calling
+\fBpcre_fullinfo()\fP with the PCRE_INFO_JIT option. A result of 1 means that
+JIT compilation was successful. A result of 0 means that JIT support is not
+available, or the pattern was not studied with PCRE_STUDY_JIT_COMPILE etc., or
+the JIT compiler was not able to handle the pattern.
+.P
+Once a pattern has been studied, with or without JIT, it can be used as many
+times as you like for matching different subject strings.
+.
+.
+.SH "UNSUPPORTED OPTIONS AND PATTERN ITEMS"
+.rs
+.sp
+The only \fBpcre_exec()\fP options that are supported for JIT execution are
+PCRE_NO_UTF8_CHECK, PCRE_NO_UTF16_CHECK, PCRE_NO_UTF32_CHECK, PCRE_NOTBOL,
+PCRE_NOTEOL, PCRE_NOTEMPTY, PCRE_NOTEMPTY_ATSTART, PCRE_PARTIAL_HARD, and
+PCRE_PARTIAL_SOFT.
+.P
+The only unsupported pattern items are \eC (match a single data unit) when
+running in a UTF mode, and a callout immediately before an assertion condition
+in a conditional group.
+.
+.
+.SH "RETURN VALUES FROM JIT EXECUTION"
+.rs
+.sp
+When a pattern is matched using JIT execution, the return values are the same
+as those given by the interpretive \fBpcre_exec()\fP code, with the addition of
+one new error code: PCRE_ERROR_JIT_STACKLIMIT. This means that the memory used
+for the JIT stack was insufficient. See
+.\" HTML <a href="#stackcontrol">
+.\" </a>
+"Controlling the JIT stack"
+.\"
+below for a discussion of JIT stack usage. For compatibility with the
+interpretive \fBpcre_exec()\fP code, no more than two-thirds of the
+\fIovector\fP argument is used for passing back captured substrings.
+.P
+The error code PCRE_ERROR_MATCHLIMIT is returned by the JIT code if searching a
+very large pattern tree goes on for too long, as it is in the same circumstance
+when JIT is not used, but the details of exactly what is counted are not the
+same. The PCRE_ERROR_RECURSIONLIMIT error code is never returned by JIT
+execution.
+.
+.
+.SH "SAVING AND RESTORING COMPILED PATTERNS"
+.rs
+.sp
+The code that is generated by the JIT compiler is architecture-specific, and is
+also position dependent. For those reasons it cannot be saved (in a file or
+database) and restored later like the bytecode and other data of a compiled
+pattern. Saving and restoring compiled patterns is not something many people
+do. More detail about this facility is given in the
+.\" HREF
+\fBpcreprecompile\fP
+.\"
+documentation. It should be possible to run \fBpcre_study()\fP on a saved and
+restored pattern, and thereby recreate the JIT data, but because JIT
+compilation uses significant resources, it is probably not worth doing this;
+you might as well recompile the original pattern.
+.
+.
+.\" HTML <a name="stackcontrol"></a>
+.SH "CONTROLLING THE JIT STACK"
+.rs
+.sp
+When the compiled JIT code runs, it needs a block of memory to use as a stack.
+By default, it uses 32K on the machine stack. However, some large or
+complicated patterns need more than this. The error PCRE_ERROR_JIT_STACKLIMIT
+is given when there is not enough stack. Three functions are provided for
+managing blocks of memory for use as JIT stacks. There is further discussion
+about the use of JIT stacks in the section entitled
+.\" HTML <a href="#stackcontrol">
+.\" </a>
+"JIT stack FAQ"
+.\"
+below.
+.P
+The \fBpcre_jit_stack_alloc()\fP function creates a JIT stack. Its arguments
+are a starting size and a maximum size, and it returns a pointer to an opaque
+structure of type \fBpcre_jit_stack\fP, or NULL if there is an error. The
+\fBpcre_jit_stack_free()\fP function can be used to free a stack that is no
+longer needed. (For the technically minded: the address space is allocated by
+mmap or VirtualAlloc.)
+.P
+JIT uses far less memory for recursion than the interpretive code,
+and a maximum stack size of 512K to 1M should be more than enough for any
+pattern.
+.P
+The \fBpcre_assign_jit_stack()\fP function specifies which stack JIT code
+should use. Its arguments are as follows:
+.sp
+  pcre_extra         *extra
+  pcre_jit_callback  callback
+  void               *data
+.sp
+The \fIextra\fP argument must be the result of studying a pattern with
+PCRE_STUDY_JIT_COMPILE etc. There are three cases for the values of the other
+two options:
+.sp
+  (1) If \fIcallback\fP is NULL and \fIdata\fP is NULL, an internal 32K block
+      on the machine stack is used.
+.sp
+  (2) If \fIcallback\fP is NULL and \fIdata\fP is not NULL, \fIdata\fP must be
+      a valid JIT stack, the result of calling \fBpcre_jit_stack_alloc()\fP.
+.sp
+  (3) If \fIcallback\fP is not NULL, it must point to a function that is
+      called with \fIdata\fP as an argument at the start of matching, in
+      order to set up a JIT stack. If the return from the callback
+      function is NULL, the internal 32K stack is used; otherwise the
+      return value must be a valid JIT stack, the result of calling
+      \fBpcre_jit_stack_alloc()\fP.
+.sp
+A callback function is obeyed whenever JIT code is about to be run; it is not
+obeyed when \fBpcre_exec()\fP is called with options that are incompatible for
+JIT execution. A callback function can therefore be used to determine whether a
+match operation was executed by JIT or by the interpreter.
+.P
+You may safely use the same JIT stack for more than one pattern (either by
+assigning directly or by callback), as long as the patterns are all matched
+sequentially in the same thread. In a multithread application, if you do not
+specify a JIT stack, or if you assign or pass back NULL from a callback, that
+is thread-safe, because each thread has its own machine stack. However, if you
+assign or pass back a non-NULL JIT stack, this must be a different stack for
+each thread so that the application is thread-safe.
+.P
+Strictly speaking, even more is allowed. You can assign the same non-NULL stack
+to any number of patterns as long as they are not used for matching by multiple
+threads at the same time. For example, you can assign the same stack to all
+compiled patterns, and use a global mutex in the callback to wait until the
+stack is available for use. However, this is an inefficient solution, and not
+recommended.
+.P
+This is a suggestion for how a multithreaded program that needs to set up
+non-default JIT stacks might operate:
+.sp
+  During thread initalization
+    thread_local_var = pcre_jit_stack_alloc(...)
+.sp
+  During thread exit
+    pcre_jit_stack_free(thread_local_var)
+.sp
+  Use a one-line callback function
+    return thread_local_var
+.sp
+All the functions described in this section do nothing if JIT is not available,
+and \fBpcre_assign_jit_stack()\fP does nothing unless the \fBextra\fP argument
+is non-NULL and points to a \fBpcre_extra\fP block that is the result of a
+successful study with PCRE_STUDY_JIT_COMPILE etc.
+.
+.
+.\" HTML <a name="stackfaq"></a>
+.SH "JIT STACK FAQ"
+.rs
+.sp
+(1) Why do we need JIT stacks?
+.sp
+PCRE (and JIT) is a recursive, depth-first engine, so it needs a stack where
+the local data of the current node is pushed before checking its child nodes.
+Allocating real machine stack on some platforms is difficult. For example, the
+stack chain needs to be updated every time if we extend the stack on PowerPC.
+Although it is possible, its updating time overhead decreases performance. So
+we do the recursion in memory.
+.P
+(2) Why don't we simply allocate blocks of memory with \fBmalloc()\fP?
+.sp
+Modern operating systems have a nice feature: they can reserve an address space
+instead of allocating memory. We can safely allocate memory pages inside this
+address space, so the stack could grow without moving memory data (this is
+important because of pointers). Thus we can allocate 1M address space, and use
+only a single memory page (usually 4K) if that is enough. However, we can still
+grow up to 1M anytime if needed.
+.P
+(3) Who "owns" a JIT stack?
+.sp
+The owner of the stack is the user program, not the JIT studied pattern or
+anything else. The user program must ensure that if a stack is used by
+\fBpcre_exec()\fP, (that is, it is assigned to the pattern currently running),
+that stack must not be used by any other threads (to avoid overwriting the same
+memory area). The best practice for multithreaded programs is to allocate a
+stack for each thread, and return this stack through the JIT callback function.
+.P
+(4) When should a JIT stack be freed?
+.sp
+You can free a JIT stack at any time, as long as it will not be used by
+\fBpcre_exec()\fP again. When you assign the stack to a pattern, only a pointer
+is set. There is no reference counting or any other magic. You can free the
+patterns and stacks in any order, anytime. Just \fIdo not\fP call
+\fBpcre_exec()\fP with a pattern pointing to an already freed stack, as that
+will cause SEGFAULT. (Also, do not free a stack currently used by
+\fBpcre_exec()\fP in another thread). You can also replace the stack for a
+pattern at any time. You can even free the previous stack before assigning a
+replacement.
+.P
+(5) Should I allocate/free a stack every time before/after calling
+\fBpcre_exec()\fP?
+.sp
+No, because this is too costly in terms of resources. However, you could
+implement some clever idea which release the stack if it is not used in let's
+say two minutes. The JIT callback can help to achieve this without keeping a
+list of the currently JIT studied patterns.
+.P
+(6) OK, the stack is for long term memory allocation. But what happens if a
+pattern causes stack overflow with a stack of 1M? Is that 1M kept until the
+stack is freed?
+.sp
+Especially on embedded sytems, it might be a good idea to release memory
+sometimes without freeing the stack. There is no API for this at the moment.
+Probably a function call which returns with the currently allocated memory for
+any stack and another which allows releasing memory (shrinking the stack) would
+be a good idea if someone needs this.
+.P
+(7) This is too much of a headache. Isn't there any better solution for JIT
+stack handling?
+.sp
+No, thanks to Windows. If POSIX threads were used everywhere, we could throw
+out this complicated API.
+.
+.
+.SH "EXAMPLE CODE"
+.rs
+.sp
+This is a single-threaded example that specifies a JIT stack without using a
+callback.
+.sp
+  int rc;
+  int ovector[30];
+  pcre *re;
+  pcre_extra *extra;
+  pcre_jit_stack *jit_stack;
+.sp
+  re = pcre_compile(pattern, 0, &error, &erroffset, NULL);
+  /* Check for errors */
+  extra = pcre_study(re, PCRE_STUDY_JIT_COMPILE, &error);
+  jit_stack = pcre_jit_stack_alloc(32*1024, 512*1024);
+  /* Check for error (NULL) */
+  pcre_assign_jit_stack(extra, NULL, jit_stack);
+  rc = pcre_exec(re, extra, subject, length, 0, 0, ovector, 30);
+  /* Check results */
+  pcre_free(re);
+  pcre_free_study(extra);
+  pcre_jit_stack_free(jit_stack);
+.sp
+.
+.
+.SH "JIT FAST PATH API"
+.rs
+.sp
+Because the API described above falls back to interpreted execution when JIT is
+not available, it is convenient for programs that are written for general use
+in many environments. However, calling JIT via \fBpcre_exec()\fP does have a
+performance impact. Programs that are written for use where JIT is known to be
+available, and which need the best possible performance, can instead use a
+"fast path" API to call JIT execution directly instead of calling
+\fBpcre_exec()\fP (obviously only for patterns that have been successfully
+studied by JIT).
+.P
+The fast path function is called \fBpcre_jit_exec()\fP, and it takes exactly
+the same arguments as \fBpcre_exec()\fP, plus one additional argument that
+must point to a JIT stack. The JIT stack arrangements described above do not
+apply. The return values are the same as for \fBpcre_exec()\fP.
+.P
+When you call \fBpcre_exec()\fP, as well as testing for invalid options, a
+number of other sanity checks are performed on the arguments. For example, if
+the subject pointer is NULL, or its length is negative, an immediate error is
+given. Also, unless PCRE_NO_UTF[8|16|32] is set, a UTF subject string is tested
+for validity. In the interests of speed, these checks do not happen on the JIT
+fast path, and if invalid data is passed, the result is undefined.
+.P
+Bypassing the sanity checks and the \fBpcre_exec()\fP wrapping can give
+speedups of more than 10%.
+.
+.
+.SH "SEE ALSO"
+.rs
+.sp
+\fBpcreapi\fP(3)
+.
+.
+.SH AUTHOR
+.rs
+.sp
+.nf
+Philip Hazel (FAQ by Zoltan Herczeg)
+University Computing Service
+Cambridge CB2 3QH, England.
+.fi
+.
+.
+.SH REVISION
+.rs
+.sp
+.nf
+Last updated: 17 March 2013
+Copyright (c) 1997-2013 University of Cambridge.
+.fi
diff --git a/libs/Pcre16/docs/doc/pcrelimits.3 b/libs/Pcre16/docs/doc/pcrelimits.3
new file mode 100644
index 0000000000..423d6a2768
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcrelimits.3
@@ -0,0 +1,71 @@
+.TH PCRELIMITS 3 "05 November 2013" "PCRE 8.34"
+.SH NAME
+PCRE - Perl-compatible regular expressions
+.SH "SIZE AND OTHER LIMITATIONS"
+.rs
+.sp
+There are some size limitations in PCRE but it is hoped that they will never in
+practice be relevant.
+.P
+The maximum length of a compiled pattern is approximately 64K data units (bytes
+for the 8-bit library, 16-bit units for the 16-bit library, and 32-bit units for
+the 32-bit library) if PCRE is compiled with the default internal linkage size,
+which is 2 bytes for the 8-bit and 16-bit libraries, and 4 bytes for the 32-bit
+library. If you want to process regular expressions that are truly enormous,
+you can compile PCRE with an internal linkage size of 3 or 4 (when building the
+16-bit or 32-bit library, 3 is rounded up to 4). See the \fBREADME\fP file in
+the source distribution and the
+.\" HREF
+\fBpcrebuild\fP
+.\"
+documentation for details. In these cases the limit is substantially larger.
+However, the speed of execution is slower.
+.P
+All values in repeating quantifiers must be less than 65536.
+.P
+There is no limit to the number of parenthesized subpatterns, but there can be
+no more than 65535 capturing subpatterns. There is, however, a limit to the
+depth of nesting of parenthesized subpatterns of all kinds. This is imposed in
+order to limit the amount of system stack used at compile time. The limit can
+be specified when PCRE is built; the default is 250.
+.P
+There is a limit to the number of forward references to subsequent subpatterns
+of around 200,000. Repeated forward references with fixed upper limits, for
+example, (?2){0,100} when subpattern number 2 is to the right, are included in
+the count. There is no limit to the number of backward references.
+.P
+The maximum length of name for a named subpattern is 32 characters, and the
+maximum number of named subpatterns is 10000.
+.P
+The maximum length of a name in a (*MARK), (*PRUNE), (*SKIP), or (*THEN) verb
+is 255 for the 8-bit library and 65535 for the 16-bit and 32-bit libraries.
+.P
+The maximum length of a subject string is the largest positive number that an
+integer variable can hold. However, when using the traditional matching
+function, PCRE uses recursion to handle subpatterns and indefinite repetition.
+This means that the available stack space may limit the size of a subject
+string that can be processed by certain patterns. For a discussion of stack
+issues, see the
+.\" HREF
+\fBpcrestack\fP
+.\"
+documentation.
+.
+.
+.SH AUTHOR
+.rs
+.sp
+.nf
+Philip Hazel
+University Computing Service
+Cambridge CB2 3QH, England.
+.fi
+.
+.
+.SH REVISION
+.rs
+.sp
+.nf
+Last updated: 05 November 2013
+Copyright (c) 1997-2013 University of Cambridge.
+.fi
diff --git a/libs/Pcre16/docs/doc/pcrematching.3 b/libs/Pcre16/docs/doc/pcrematching.3
new file mode 100644
index 0000000000..268baf9b8c
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcrematching.3
@@ -0,0 +1,214 @@
+.TH PCREMATCHING 3 "12 November 2013" "PCRE 8.34"
+.SH NAME
+PCRE - Perl-compatible regular expressions
+.SH "PCRE MATCHING ALGORITHMS"
+.rs
+.sp
+This document describes the two different algorithms that are available in PCRE
+for matching a compiled regular expression against a given subject string. The
+"standard" algorithm is the one provided by the \fBpcre_exec()\fP,
+\fBpcre16_exec()\fP and \fBpcre32_exec()\fP functions. These work in the same
+as as Perl's matching function, and provide a Perl-compatible matching operation.
+The just-in-time (JIT) optimization that is described in the
+.\" HREF
+\fBpcrejit\fP
+.\"
+documentation is compatible with these functions.
+.P
+An alternative algorithm is provided by the \fBpcre_dfa_exec()\fP,
+\fBpcre16_dfa_exec()\fP and \fBpcre32_dfa_exec()\fP functions; they operate in
+a different way, and are not Perl-compatible. This alternative has advantages
+and disadvantages compared with the standard algorithm, and these are described
+below.
+.P
+When there is only one possible way in which a given subject string can match a
+pattern, the two algorithms give the same answer. A difference arises, however,
+when there are multiple possibilities. For example, if the pattern
+.sp
+  ^<.*>
+.sp
+is matched against the string
+.sp
+  <something> <something else> <something further>
+.sp
+there are three possible answers. The standard algorithm finds only one of
+them, whereas the alternative algorithm finds all three.
+.
+.
+.SH "REGULAR EXPRESSIONS AS TREES"
+.rs
+.sp
+The set of strings that are matched by a regular expression can be represented
+as a tree structure. An unlimited repetition in the pattern makes the tree of
+infinite size, but it is still a tree. Matching the pattern to a given subject
+string (from a given starting point) can be thought of as a search of the tree.
+There are two ways to search a tree: depth-first and breadth-first, and these
+correspond to the two matching algorithms provided by PCRE.
+.
+.
+.SH "THE STANDARD MATCHING ALGORITHM"
+.rs
+.sp
+In the terminology of Jeffrey Friedl's book "Mastering Regular
+Expressions", the standard algorithm is an "NFA algorithm". It conducts a
+depth-first search of the pattern tree. That is, it proceeds along a single
+path through the tree, checking that the subject matches what is required. When
+there is a mismatch, the algorithm tries any alternatives at the current point,
+and if they all fail, it backs up to the previous branch point in the tree, and
+tries the next alternative branch at that level. This often involves backing up
+(moving to the left) in the subject string as well. The order in which
+repetition branches are tried is controlled by the greedy or ungreedy nature of
+the quantifier.
+.P
+If a leaf node is reached, a matching string has been found, and at that point
+the algorithm stops. Thus, if there is more than one possible match, this
+algorithm returns the first one that it finds. Whether this is the shortest,
+the longest, or some intermediate length depends on the way the greedy and
+ungreedy repetition quantifiers are specified in the pattern.
+.P
+Because it ends up with a single path through the tree, it is relatively
+straightforward for this algorithm to keep track of the substrings that are
+matched by portions of the pattern in parentheses. This provides support for
+capturing parentheses and back references.
+.
+.
+.SH "THE ALTERNATIVE MATCHING ALGORITHM"
+.rs
+.sp
+This algorithm conducts a breadth-first search of the tree. Starting from the
+first matching point in the subject, it scans the subject string from left to
+right, once, character by character, and as it does this, it remembers all the
+paths through the tree that represent valid matches. In Friedl's terminology,
+this is a kind of "DFA algorithm", though it is not implemented as a
+traditional finite state machine (it keeps multiple states active
+simultaneously).
+.P
+Although the general principle of this matching algorithm is that it scans the
+subject string only once, without backtracking, there is one exception: when a
+lookaround assertion is encountered, the characters following or preceding the
+current point have to be independently inspected.
+.P
+The scan continues until either the end of the subject is reached, or there are
+no more unterminated paths. At this point, terminated paths represent the
+different matching possibilities (if there are none, the match has failed).
+Thus, if there is more than one possible match, this algorithm finds all of
+them, and in particular, it finds the longest. The matches are returned in
+decreasing order of length. There is an option to stop the algorithm after the
+first match (which is necessarily the shortest) is found.
+.P
+Note that all the matches that are found start at the same point in the
+subject. If the pattern
+.sp
+  cat(er(pillar)?)?
+.sp
+is matched against the string "the caterpillar catchment", the result will be
+the three strings "caterpillar", "cater", and "cat" that start at the fifth
+character of the subject. The algorithm does not automatically move on to find
+matches that start at later positions.
+.P
+PCRE's "auto-possessification" optimization usually applies to character
+repeats at the end of a pattern (as well as internally). For example, the
+pattern "a\ed+" is compiled as if it were "a\ed++" because there is no point
+even considering the possibility of backtracking into the repeated digits. For
+DFA matching, this means that only one possible match is found. If you really
+do want multiple matches in such cases, either use an ungreedy repeat
+("a\ed+?") or set the PCRE_NO_AUTO_POSSESS option when compiling.
+.P
+There are a number of features of PCRE regular expressions that are not
+supported by the alternative matching algorithm. They are as follows:
+.P
+1. Because the algorithm finds all possible matches, the greedy or ungreedy
+nature of repetition quantifiers is not relevant. Greedy and ungreedy
+quantifiers are treated in exactly the same way. However, possessive
+quantifiers can make a difference when what follows could also match what is
+quantified, for example in a pattern like this:
+.sp
+  ^a++\ew!
+.sp
+This pattern matches "aaab!" but not "aaa!", which would be matched by a
+non-possessive quantifier. Similarly, if an atomic group is present, it is
+matched as if it were a standalone pattern at the current point, and the
+longest match is then "locked in" for the rest of the overall pattern.
+.P
+2. When dealing with multiple paths through the tree simultaneously, it is not
+straightforward to keep track of captured substrings for the different matching
+possibilities, and PCRE's implementation of this algorithm does not attempt to
+do this. This means that no captured substrings are available.
+.P
+3. Because no substrings are captured, back references within the pattern are
+not supported, and cause errors if encountered.
+.P
+4. For the same reason, conditional expressions that use a backreference as the
+condition or test for a specific group recursion are not supported.
+.P
+5. Because many paths through the tree may be active, the \eK escape sequence,
+which resets the start of the match when encountered (but may be on some paths
+and not on others), is not supported. It causes an error if encountered.
+.P
+6. Callouts are supported, but the value of the \fIcapture_top\fP field is
+always 1, and the value of the \fIcapture_last\fP field is always -1.
+.P
+7. The \eC escape sequence, which (in the standard algorithm) always matches a
+single data unit, even in UTF-8, UTF-16 or UTF-32 modes, is not supported in
+these modes, because the alternative algorithm moves through the subject string
+one character (not data unit) at a time, for all active paths through the tree.
+.P
+8. Except for (*FAIL), the backtracking control verbs such as (*PRUNE) are not
+supported. (*FAIL) is supported, and behaves like a failing negative assertion.
+.
+.
+.SH "ADVANTAGES OF THE ALTERNATIVE ALGORITHM"
+.rs
+.sp
+Using the alternative matching algorithm provides the following advantages:
+.P
+1. All possible matches (at a single point in the subject) are automatically
+found, and in particular, the longest match is found. To find more than one
+match using the standard algorithm, you have to do kludgy things with
+callouts.
+.P
+2. Because the alternative algorithm scans the subject string just once, and
+never needs to backtrack (except for lookbehinds), it is possible to pass very
+long subject strings to the matching function in several pieces, checking for
+partial matching each time. Although it is possible to do multi-segment
+matching using the standard algorithm by retaining partially matched
+substrings, it is more complicated. The
+.\" HREF
+\fBpcrepartial\fP
+.\"
+documentation gives details of partial matching and discusses multi-segment
+matching.
+.
+.
+.SH "DISADVANTAGES OF THE ALTERNATIVE ALGORITHM"
+.rs
+.sp
+The alternative algorithm suffers from a number of disadvantages:
+.P
+1. It is substantially slower than the standard algorithm. This is partly
+because it has to search for all possible matches, but is also because it is
+less susceptible to optimization.
+.P
+2. Capturing parentheses and back references are not supported.
+.P
+3. Although atomic groups are supported, their use does not provide the
+performance advantage that it does for the standard algorithm.
+.
+.
+.SH AUTHOR
+.rs
+.sp
+.nf
+Philip Hazel
+University Computing Service
+Cambridge CB2 3QH, England.
+.fi
+.
+.
+.SH REVISION
+.rs
+.sp
+.nf
+Last updated: 12 November 2013
+Copyright (c) 1997-2012 University of Cambridge.
+.fi
diff --git a/libs/Pcre16/docs/doc/pcrepartial.3 b/libs/Pcre16/docs/doc/pcrepartial.3
new file mode 100644
index 0000000000..14d0124f1c
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcrepartial.3
@@ -0,0 +1,476 @@
+.TH PCREPARTIAL 3 "02 July 2013" "PCRE 8.34"
+.SH NAME
+PCRE - Perl-compatible regular expressions
+.SH "PARTIAL MATCHING IN PCRE"
+.rs
+.sp
+In normal use of PCRE, if the subject string that is passed to a matching
+function matches as far as it goes, but is too short to match the entire
+pattern, PCRE_ERROR_NOMATCH is returned. There are circumstances where it might
+be helpful to distinguish this case from other cases in which there is no
+match.
+.P
+Consider, for example, an application where a human is required to type in data
+for a field with specific formatting requirements. An example might be a date
+in the form \fIddmmmyy\fP, defined by this pattern:
+.sp
+  ^\ed?\ed(jan|feb|mar|apr|may|jun|jul|aug|sep|oct|nov|dec)\ed\ed$
+.sp
+If the application sees the user's keystrokes one by one, and can check that
+what has been typed so far is potentially valid, it is able to raise an error
+as soon as a mistake is made, by beeping and not reflecting the character that
+has been typed, for example. This immediate feedback is likely to be a better
+user interface than a check that is delayed until the entire string has been
+entered. Partial matching can also be useful when the subject string is very
+long and is not all available at once.
+.P
+PCRE supports partial matching by means of the PCRE_PARTIAL_SOFT and
+PCRE_PARTIAL_HARD options, which can be set when calling any of the matching
+functions. For backwards compatibility, PCRE_PARTIAL is a synonym for
+PCRE_PARTIAL_SOFT. The essential difference between the two options is whether
+or not a partial match is preferred to an alternative complete match, though
+the details differ between the two types of matching function. If both options
+are set, PCRE_PARTIAL_HARD takes precedence.
+.P
+If you want to use partial matching with just-in-time optimized code, you must
+call \fBpcre_study()\fP, \fBpcre16_study()\fP or  \fBpcre32_study()\fP with one
+or both of these options:
+.sp
+  PCRE_STUDY_JIT_PARTIAL_SOFT_COMPILE
+  PCRE_STUDY_JIT_PARTIAL_HARD_COMPILE
+.sp
+PCRE_STUDY_JIT_COMPILE should also be set if you are going to run non-partial
+matches on the same pattern. If the appropriate JIT study mode has not been set
+for a match, the interpretive matching code is used.
+.P
+Setting a partial matching option disables two of PCRE's standard
+optimizations. PCRE remembers the last literal data unit in a pattern, and
+abandons matching immediately if it is not present in the subject string. This
+optimization cannot be used for a subject string that might match only
+partially. If the pattern was studied, PCRE knows the minimum length of a
+matching string, and does not bother to run the matching function on shorter
+strings. This optimization is also disabled for partial matching.
+.
+.
+.SH "PARTIAL MATCHING USING pcre_exec() OR pcre[16|32]_exec()"
+.rs
+.sp
+A partial match occurs during a call to \fBpcre_exec()\fP or
+\fBpcre[16|32]_exec()\fP when the end of the subject string is reached
+successfully, but matching cannot continue because more characters are needed.
+However, at least one character in the subject must have been inspected. This
+character need not form part of the final matched string; lookbehind assertions
+and the \eK escape sequence provide ways of inspecting characters before the
+start of a matched substring. The requirement for inspecting at least one
+character exists because an empty string can always be matched; without such a
+restriction there would always be a partial match of an empty string at the end
+of the subject.
+.P
+If there are at least two slots in the offsets vector when a partial match is
+returned, the first slot is set to the offset of the earliest character that
+was inspected. For convenience, the second offset points to the end of the
+subject so that a substring can easily be identified. If there are at least
+three slots in the offsets vector, the third slot is set to the offset of the
+character where matching started.
+.P
+For the majority of patterns, the contents of the first and third slots will be
+the same. However, for patterns that contain lookbehind assertions, or begin
+with \eb or \eB, characters before the one where matching started may have been
+inspected while carrying out the match. For example, consider this pattern:
+.sp
+  /(?<=abc)123/
+.sp
+This pattern matches "123", but only if it is preceded by "abc". If the subject
+string is "xyzabc12", the first two offsets after a partial match are for the
+substring "abc12", because all these characters were inspected. However, the
+third offset is set to 6, because that is the offset where matching began.
+.P
+What happens when a partial match is identified depends on which of the two
+partial matching options are set.
+.
+.
+.SS "PCRE_PARTIAL_SOFT WITH pcre_exec() OR pcre[16|32]_exec()"
+.rs
+.sp
+If PCRE_PARTIAL_SOFT is set when \fBpcre_exec()\fP or \fBpcre[16|32]_exec()\fP
+identifies a partial match, the partial match is remembered, but matching
+continues as normal, and other alternatives in the pattern are tried. If no
+complete match can be found, PCRE_ERROR_PARTIAL is returned instead of
+PCRE_ERROR_NOMATCH.
+.P
+This option is "soft" because it prefers a complete match over a partial match.
+All the various matching items in a pattern behave as if the subject string is
+potentially complete. For example, \ez, \eZ, and $ match at the end of the
+subject, as normal, and for \eb and \eB the end of the subject is treated as a
+non-alphanumeric.
+.P
+If there is more than one partial match, the first one that was found provides
+the data that is returned. Consider this pattern:
+.sp
+  /123\ew+X|dogY/
+.sp
+If this is matched against the subject string "abc123dog", both
+alternatives fail to match, but the end of the subject is reached during
+matching, so PCRE_ERROR_PARTIAL is returned. The offsets are set to 3 and 9,
+identifying "123dog" as the first partial match that was found. (In this
+example, there are two partial matches, because "dog" on its own partially
+matches the second alternative.)
+.
+.
+.SS "PCRE_PARTIAL_HARD WITH pcre_exec() OR pcre[16|32]_exec()"
+.rs
+.sp
+If PCRE_PARTIAL_HARD is set for \fBpcre_exec()\fP or \fBpcre[16|32]_exec()\fP,
+PCRE_ERROR_PARTIAL is returned as soon as a partial match is found, without
+continuing to search for possible complete matches. This option is "hard"
+because it prefers an earlier partial match over a later complete match. For
+this reason, the assumption is made that the end of the supplied subject string
+may not be the true end of the available data, and so, if \ez, \eZ, \eb, \eB,
+or $ are encountered at the end of the subject, the result is
+PCRE_ERROR_PARTIAL, provided that at least one character in the subject has
+been inspected.
+.P
+Setting PCRE_PARTIAL_HARD also affects the way UTF-8 and UTF-16
+subject strings are checked for validity. Normally, an invalid sequence
+causes the error PCRE_ERROR_BADUTF8 or PCRE_ERROR_BADUTF16. However, in the
+special case of a truncated character at the end of the subject,
+PCRE_ERROR_SHORTUTF8 or PCRE_ERROR_SHORTUTF16 is returned when
+PCRE_PARTIAL_HARD is set.
+.
+.
+.SS "Comparing hard and soft partial matching"
+.rs
+.sp
+The difference between the two partial matching options can be illustrated by a
+pattern such as:
+.sp
+  /dog(sbody)?/
+.sp
+This matches either "dog" or "dogsbody", greedily (that is, it prefers the
+longer string if possible). If it is matched against the string "dog" with
+PCRE_PARTIAL_SOFT, it yields a complete match for "dog". However, if
+PCRE_PARTIAL_HARD is set, the result is PCRE_ERROR_PARTIAL. On the other hand,
+if the pattern is made ungreedy the result is different:
+.sp
+  /dog(sbody)??/
+.sp
+In this case the result is always a complete match because that is found first,
+and matching never continues after finding a complete match. It might be easier
+to follow this explanation by thinking of the two patterns like this:
+.sp
+  /dog(sbody)?/    is the same as  /dogsbody|dog/
+  /dog(sbody)??/   is the same as  /dog|dogsbody/
+.sp
+The second pattern will never match "dogsbody", because it will always find the
+shorter match first.
+.
+.
+.SH "PARTIAL MATCHING USING pcre_dfa_exec() OR pcre[16|32]_dfa_exec()"
+.rs
+.sp
+The DFA functions move along the subject string character by character, without
+backtracking, searching for all possible matches simultaneously. If the end of
+the subject is reached before the end of the pattern, there is the possibility
+of a partial match, again provided that at least one character has been
+inspected.
+.P
+When PCRE_PARTIAL_SOFT is set, PCRE_ERROR_PARTIAL is returned only if there
+have been no complete matches. Otherwise, the complete matches are returned.
+However, if PCRE_PARTIAL_HARD is set, a partial match takes precedence over any
+complete matches. The portion of the string that was inspected when the longest
+partial match was found is set as the first matching string, provided there are
+at least two slots in the offsets vector.
+.P
+Because the DFA functions always search for all possible matches, and there is
+no difference between greedy and ungreedy repetition, their behaviour is
+different from the standard functions when PCRE_PARTIAL_HARD is set. Consider
+the string "dog" matched against the ungreedy pattern shown above:
+.sp
+  /dog(sbody)??/
+.sp
+Whereas the standard functions stop as soon as they find the complete match for
+"dog", the DFA functions also find the partial match for "dogsbody", and so
+return that when PCRE_PARTIAL_HARD is set.
+.
+.
+.SH "PARTIAL MATCHING AND WORD BOUNDARIES"
+.rs
+.sp
+If a pattern ends with one of sequences \eb or \eB, which test for word
+boundaries, partial matching with PCRE_PARTIAL_SOFT can give counter-intuitive
+results. Consider this pattern:
+.sp
+  /\ebcat\eb/
+.sp
+This matches "cat", provided there is a word boundary at either end. If the
+subject string is "the cat", the comparison of the final "t" with a following
+character cannot take place, so a partial match is found. However, normal
+matching carries on, and \eb matches at the end of the subject when the last
+character is a letter, so a complete match is found. The result, therefore, is
+\fInot\fP PCRE_ERROR_PARTIAL. Using PCRE_PARTIAL_HARD in this case does yield
+PCRE_ERROR_PARTIAL, because then the partial match takes precedence.
+.
+.
+.SH "FORMERLY RESTRICTED PATTERNS"
+.rs
+.sp
+For releases of PCRE prior to 8.00, because of the way certain internal
+optimizations were implemented in the \fBpcre_exec()\fP function, the
+PCRE_PARTIAL option (predecessor of PCRE_PARTIAL_SOFT) could not be used with
+all patterns. From release 8.00 onwards, the restrictions no longer apply, and
+partial matching with can be requested for any pattern.
+.P
+Items that were formerly restricted were repeated single characters and
+repeated metasequences. If PCRE_PARTIAL was set for a pattern that did not
+conform to the restrictions, \fBpcre_exec()\fP returned the error code
+PCRE_ERROR_BADPARTIAL (-13). This error code is no longer in use. The
+PCRE_INFO_OKPARTIAL call to \fBpcre_fullinfo()\fP to find out if a compiled
+pattern can be used for partial matching now always returns 1.
+.
+.
+.SH "EXAMPLE OF PARTIAL MATCHING USING PCRETEST"
+.rs
+.sp
+If the escape sequence \eP is present in a \fBpcretest\fP data line, the
+PCRE_PARTIAL_SOFT option is used for the match. Here is a run of \fBpcretest\fP
+that uses the date example quoted above:
+.sp
+    re> /^\ed?\ed(jan|feb|mar|apr|may|jun|jul|aug|sep|oct|nov|dec)\ed\ed$/
+  data> 25jun04\eP
+   0: 25jun04
+   1: jun
+  data> 25dec3\eP
+  Partial match: 23dec3
+  data> 3ju\eP
+  Partial match: 3ju
+  data> 3juj\eP
+  No match
+  data> j\eP
+  No match
+.sp
+The first data string is matched completely, so \fBpcretest\fP shows the
+matched substrings. The remaining four strings do not match the complete
+pattern, but the first two are partial matches. Similar output is obtained
+if DFA matching is used.
+.P
+If the escape sequence \eP is present more than once in a \fBpcretest\fP data
+line, the PCRE_PARTIAL_HARD option is set for the match.
+.
+.
+.SH "MULTI-SEGMENT MATCHING WITH pcre_dfa_exec() OR pcre[16|32]_dfa_exec()"
+.rs
+.sp
+When a partial match has been found using a DFA matching function, it is
+possible to continue the match by providing additional subject data and calling
+the function again with the same compiled regular expression, this time setting
+the PCRE_DFA_RESTART option. You must pass the same working space as before,
+because this is where details of the previous partial match are stored. Here is
+an example using \fBpcretest\fP, using the \eR escape sequence to set the
+PCRE_DFA_RESTART option (\eD specifies the use of the DFA matching function):
+.sp
+    re> /^\ed?\ed(jan|feb|mar|apr|may|jun|jul|aug|sep|oct|nov|dec)\ed\ed$/
+  data> 23ja\eP\eD
+  Partial match: 23ja
+  data> n05\eR\eD
+   0: n05
+.sp
+The first call has "23ja" as the subject, and requests partial matching; the
+second call has "n05" as the subject for the continued (restarted) match.
+Notice that when the match is complete, only the last part is shown; PCRE does
+not retain the previously partially-matched string. It is up to the calling
+program to do that if it needs to.
+.P
+That means that, for an unanchored pattern, if a continued match fails, it is
+not possible to try again at a new starting point. All this facility is capable
+of doing is continuing with the previous match attempt. In the previous
+example, if the second set of data is "ug23" the result is no match, even
+though there would be a match for "aug23" if the entire string were given at
+once. Depending on the application, this may or may not be what you want.
+The only way to allow for starting again at the next character is to retain the
+matched part of the subject and try a new complete match.
+.P
+You can set the PCRE_PARTIAL_SOFT or PCRE_PARTIAL_HARD options with
+PCRE_DFA_RESTART to continue partial matching over multiple segments. This
+facility can be used to pass very long subject strings to the DFA matching
+functions.
+.
+.
+.SH "MULTI-SEGMENT MATCHING WITH pcre_exec() OR pcre[16|32]_exec()"
+.rs
+.sp
+From release 8.00, the standard matching functions can also be used to do
+multi-segment matching. Unlike the DFA functions, it is not possible to
+restart the previous match with a new segment of data. Instead, new data must
+be added to the previous subject string, and the entire match re-run, starting
+from the point where the partial match occurred. Earlier data can be discarded.
+.P
+It is best to use PCRE_PARTIAL_HARD in this situation, because it does not
+treat the end of a segment as the end of the subject when matching \ez, \eZ,
+\eb, \eB, and $. Consider an unanchored pattern that matches dates:
+.sp
+    re> /\ed?\ed(jan|feb|mar|apr|may|jun|jul|aug|sep|oct|nov|dec)\ed\ed/
+  data> The date is 23ja\eP\eP
+  Partial match: 23ja
+.sp
+At this stage, an application could discard the text preceding "23ja", add on
+text from the next segment, and call the matching function again. Unlike the
+DFA matching functions, the entire matching string must always be available,
+and the complete matching process occurs for each call, so more memory and more
+processing time is needed.
+.P
+\fBNote:\fP If the pattern contains lookbehind assertions, or \eK, or starts
+with \eb or \eB, the string that is returned for a partial match includes
+characters that precede the start of what would be returned for a complete
+match, because it contains all the characters that were inspected during the
+partial match.
+.
+.
+.SH "ISSUES WITH MULTI-SEGMENT MATCHING"
+.rs
+.sp
+Certain types of pattern may give problems with multi-segment matching,
+whichever matching function is used.
+.P
+1. If the pattern contains a test for the beginning of a line, you need to pass
+the PCRE_NOTBOL option when the subject string for any call does start at the
+beginning of a line. There is also a PCRE_NOTEOL option, but in practice when
+doing multi-segment matching you should be using PCRE_PARTIAL_HARD, which
+includes the effect of PCRE_NOTEOL.
+.P
+2. Lookbehind assertions that have already been obeyed are catered for in the
+offsets that are returned for a partial match. However a lookbehind assertion
+later in the pattern could require even earlier characters to be inspected. You
+can handle this case by using the PCRE_INFO_MAXLOOKBEHIND option of the
+\fBpcre_fullinfo()\fP or \fBpcre[16|32]_fullinfo()\fP functions to obtain the
+length of the longest lookbehind in the pattern. This length is given in
+characters, not bytes. If you always retain at least that many characters
+before the partially matched string, all should be well. (Of course, near the
+start of the subject, fewer characters may be present; in that case all
+characters should be retained.)
+.P
+From release 8.33, there is a more accurate way of deciding which characters to
+retain. Instead of subtracting the length of the longest lookbehind from the
+earliest inspected character (\fIoffsets[0]\fP), the match start position
+(\fIoffsets[2]\fP) should be used, and the next match attempt started at the
+\fIoffsets[2]\fP character by setting the \fIstartoffset\fP argument of
+\fBpcre_exec()\fP or \fBpcre_dfa_exec()\fP.
+.P
+For example, if the pattern "(?<=123)abc" is partially
+matched against the string "xx123a", the three offset values returned are 2, 6,
+and 5. This indicates that the matching process that gave a partial match
+started at offset 5, but the characters "123a" were all inspected. The maximum
+lookbehind for that pattern is 3, so taking that away from 5 shows that we need
+only keep "123a", and the next match attempt can be started at offset 3 (that
+is, at "a") when further characters have been added. When the match start is
+not the earliest inspected character, \fBpcretest\fP shows it explicitly:
+.sp
+    re> "(?<=123)abc"
+  data> xx123a\eP\eP
+  Partial match at offset 5: 123a
+.P
+3. Because a partial match must always contain at least one character, what
+might be considered a partial match of an empty string actually gives a "no
+match" result. For example:
+.sp
+    re> /c(?<=abc)x/
+  data> ab\eP
+  No match
+.sp
+If the next segment begins "cx", a match should be found, but this will only
+happen if characters from the previous segment are retained. For this reason, a
+"no match" result should be interpreted as "partial match of an empty string"
+when the pattern contains lookbehinds.
+.P
+4. Matching a subject string that is split into multiple segments may not
+always produce exactly the same result as matching over one single long string,
+especially when PCRE_PARTIAL_SOFT is used. The section "Partial Matching and
+Word Boundaries" above describes an issue that arises if the pattern ends with
+\eb or \eB. Another kind of difference may occur when there are multiple
+matching possibilities, because (for PCRE_PARTIAL_SOFT) a partial match result
+is given only when there are no completed matches. This means that as soon as
+the shortest match has been found, continuation to a new subject segment is no
+longer possible. Consider again this \fBpcretest\fP example:
+.sp
+    re> /dog(sbody)?/
+  data> dogsb\eP
+   0: dog
+  data> do\eP\eD
+  Partial match: do
+  data> gsb\eR\eP\eD
+   0: g
+  data> dogsbody\eD
+   0: dogsbody
+   1: dog
+.sp
+The first data line passes the string "dogsb" to a standard matching function,
+setting the PCRE_PARTIAL_SOFT option. Although the string is a partial match
+for "dogsbody", the result is not PCRE_ERROR_PARTIAL, because the shorter
+string "dog" is a complete match. Similarly, when the subject is presented to
+a DFA matching function in several parts ("do" and "gsb" being the first two)
+the match stops when "dog" has been found, and it is not possible to continue.
+On the other hand, if "dogsbody" is presented as a single string, a DFA
+matching function finds both matches.
+.P
+Because of these problems, it is best to use PCRE_PARTIAL_HARD when matching
+multi-segment data. The example above then behaves differently:
+.sp
+    re> /dog(sbody)?/
+  data> dogsb\eP\eP
+  Partial match: dogsb
+  data> do\eP\eD
+  Partial match: do
+  data> gsb\eR\eP\eP\eD
+  Partial match: gsb
+.sp
+5. Patterns that contain alternatives at the top level which do not all start
+with the same pattern item may not work as expected when PCRE_DFA_RESTART is
+used. For example, consider this pattern:
+.sp
+  1234|3789
+.sp
+If the first part of the subject is "ABC123", a partial match of the first
+alternative is found at offset 3. There is no partial match for the second
+alternative, because such a match does not start at the same point in the
+subject string. Attempting to continue with the string "7890" does not yield a
+match because only those alternatives that match at one point in the subject
+are remembered. The problem arises because the start of the second alternative
+matches within the first alternative. There is no problem with anchored
+patterns or patterns such as:
+.sp
+  1234|ABCD
+.sp
+where no string can be a partial match for both alternatives. This is not a
+problem if a standard matching function is used, because the entire match has
+to be rerun each time:
+.sp
+    re> /1234|3789/
+  data> ABC123\eP\eP
+  Partial match: 123
+  data> 1237890
+   0: 3789
+.sp
+Of course, instead of using PCRE_DFA_RESTART, the same technique of re-running
+the entire match can also be used with the DFA matching functions. Another
+possibility is to work with two buffers. If a partial match at offset \fIn\fP
+in the first buffer is followed by "no match" when PCRE_DFA_RESTART is used on
+the second buffer, you can then try a new match starting at offset \fIn+1\fP in
+the first buffer.
+.
+.
+.SH AUTHOR
+.rs
+.sp
+.nf
+Philip Hazel
+University Computing Service
+Cambridge CB2 3QH, England.
+.fi
+.
+.
+.SH REVISION
+.rs
+.sp
+.nf
+Last updated: 02 July 2013
+Copyright (c) 1997-2013 University of Cambridge.
+.fi
diff --git a/libs/Pcre16/docs/doc/pcrepattern.3 b/libs/Pcre16/docs/doc/pcrepattern.3
new file mode 100644
index 0000000000..f1c45cda5d
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcrepattern.3
@@ -0,0 +1,3265 @@
+.TH PCREPATTERN 3 "08 January 2014" "PCRE 8.35"
+.SH NAME
+PCRE - Perl-compatible regular expressions
+.SH "PCRE REGULAR EXPRESSION DETAILS"
+.rs
+.sp
+The syntax and semantics of the regular expressions that are supported by PCRE
+are described in detail below. There is a quick-reference syntax summary in the
+.\" HREF
+\fBpcresyntax\fP
+.\"
+page. PCRE tries to match Perl syntax and semantics as closely as it can. PCRE
+also supports some alternative regular expression syntax (which does not
+conflict with the Perl syntax) in order to provide some compatibility with
+regular expressions in Python, .NET, and Oniguruma.
+.P
+Perl's regular expressions are described in its own documentation, and
+regular expressions in general are covered in a number of books, some of which
+have copious examples. Jeffrey Friedl's "Mastering Regular Expressions",
+published by O'Reilly, covers regular expressions in great detail. This
+description of PCRE's regular expressions is intended as reference material.
+.P
+This document discusses the patterns that are supported by PCRE when one its
+main matching functions, \fBpcre_exec()\fP (8-bit) or \fBpcre[16|32]_exec()\fP
+(16- or 32-bit), is used. PCRE also has alternative matching functions,
+\fBpcre_dfa_exec()\fP and \fBpcre[16|32_dfa_exec()\fP, which match using a
+different algorithm that is not Perl-compatible. Some of the features discussed
+below are not available when DFA matching is used. The advantages and
+disadvantages of the alternative functions, and how they differ from the normal
+functions, are discussed in the
+.\" HREF
+\fBpcrematching\fP
+.\"
+page.
+.
+.
+.SH "SPECIAL START-OF-PATTERN ITEMS"
+.rs
+.sp
+A number of options that can be passed to \fBpcre_compile()\fP can also be set
+by special items at the start of a pattern. These are not Perl-compatible, but
+are provided to make these options accessible to pattern writers who are not
+able to change the program that processes the pattern. Any number of these
+items may appear, but they must all be together right at the start of the
+pattern string, and the letters must be in upper case.
+.
+.
+.SS "UTF support"
+.rs
+.sp
+The original operation of PCRE was on strings of one-byte characters. However,
+there is now also support for UTF-8 strings in the original library, an
+extra library that supports 16-bit and UTF-16 character strings, and a
+third library that supports 32-bit and UTF-32 character strings. To use these
+features, PCRE must be built to include appropriate support. When using UTF
+strings you must either call the compiling function with the PCRE_UTF8,
+PCRE_UTF16, or PCRE_UTF32 option, or the pattern must start with one of
+these special sequences:
+.sp
+  (*UTF8)
+  (*UTF16)
+  (*UTF32)
+  (*UTF)
+.sp
+(*UTF) is a generic sequence that can be used with any of the libraries.
+Starting a pattern with such a sequence is equivalent to setting the relevant
+option. How setting a UTF mode affects pattern matching is mentioned in several
+places below. There is also a summary of features in the
+.\" HREF
+\fBpcreunicode\fP
+.\"
+page.
+.P
+Some applications that allow their users to supply patterns may wish to
+restrict them to non-UTF data for security reasons. If the PCRE_NEVER_UTF
+option is set at compile time, (*UTF) etc. are not allowed, and their
+appearance causes an error.
+.
+.
+.SS "Unicode property support"
+.rs
+.sp
+Another special sequence that may appear at the start of a pattern is (*UCP).
+This has the same effect as setting the PCRE_UCP option: it causes sequences
+such as \ed and \ew to use Unicode properties to determine character types,
+instead of recognizing only characters with codes less than 128 via a lookup
+table.
+.
+.
+.SS "Disabling auto-possessification"
+.rs
+.sp
+If a pattern starts with (*NO_AUTO_POSSESS), it has the same effect as setting
+the PCRE_NO_AUTO_POSSESS option at compile time. This stops PCRE from making
+quantifiers possessive when what follows cannot match the repeated item. For
+example, by default a+b is treated as a++b. For more details, see the
+.\" HREF
+\fBpcreapi\fP
+.\"
+documentation.
+.
+.
+.SS "Disabling start-up optimizations"
+.rs
+.sp
+If a pattern starts with (*NO_START_OPT), it has the same effect as setting the
+PCRE_NO_START_OPTIMIZE option either at compile or matching time. This disables
+several optimizations for quickly reaching "no match" results. For more
+details, see the
+.\" HREF
+\fBpcreapi\fP
+.\"
+documentation.
+.
+.
+.\" HTML <a name="newlines"></a>
+.SS "Newline conventions"
+.rs
+.sp
+PCRE supports five different conventions for indicating line breaks in
+strings: a single CR (carriage return) character, a single LF (linefeed)
+character, the two-character sequence CRLF, any of the three preceding, or any
+Unicode newline sequence. The
+.\" HREF
+\fBpcreapi\fP
+.\"
+page has
+.\" HTML <a href="pcreapi.html#newlines">
+.\" </a>
+further discussion
+.\"
+about newlines, and shows how to set the newline convention in the
+\fIoptions\fP arguments for the compiling and matching functions.
+.P
+It is also possible to specify a newline convention by starting a pattern
+string with one of the following five sequences:
+.sp
+  (*CR)        carriage return
+  (*LF)        linefeed
+  (*CRLF)      carriage return, followed by linefeed
+  (*ANYCRLF)   any of the three above
+  (*ANY)       all Unicode newline sequences
+.sp
+These override the default and the options given to the compiling function. For
+example, on a Unix system where LF is the default newline sequence, the pattern
+.sp
+  (*CR)a.b
+.sp
+changes the convention to CR. That pattern matches "a\enb" because LF is no
+longer a newline. If more than one of these settings is present, the last one
+is used.
+.P
+The newline convention affects where the circumflex and dollar assertions are
+true. It also affects the interpretation of the dot metacharacter when
+PCRE_DOTALL is not set, and the behaviour of \eN. However, it does not affect
+what the \eR escape sequence matches. By default, this is any Unicode newline
+sequence, for Perl compatibility. However, this can be changed; see the
+description of \eR in the section entitled
+.\" HTML <a href="#newlineseq">
+.\" </a>
+"Newline sequences"
+.\"
+below. A change of \eR setting can be combined with a change of newline
+convention.
+.
+.
+.SS "Setting match and recursion limits"
+.rs
+.sp
+The caller of \fBpcre_exec()\fP can set a limit on the number of times the
+internal \fBmatch()\fP function is called and on the maximum depth of
+recursive calls. These facilities are provided to catch runaway matches that
+are provoked by patterns with huge matching trees (a typical example is a
+pattern with nested unlimited repeats) and to avoid running out of system stack
+by too much recursion. When one of these limits is reached, \fBpcre_exec()\fP
+gives an error return. The limits can also be set by items at the start of the
+pattern of the form
+.sp
+  (*LIMIT_MATCH=d)
+  (*LIMIT_RECURSION=d)
+.sp
+where d is any number of decimal digits. However, the value of the setting must
+be less than the value set (or defaulted) by the caller of \fBpcre_exec()\fP
+for it to have any effect. In other words, the pattern writer can lower the
+limits set by the programmer, but not raise them. If there is more than one
+setting of one of these limits, the lower value is used.
+.
+.
+.SH "EBCDIC CHARACTER CODES"
+.rs
+.sp
+PCRE can be compiled to run in an environment that uses EBCDIC as its character
+code rather than ASCII or Unicode (typically a mainframe system). In the
+sections below, character code values are ASCII or Unicode; in an EBCDIC
+environment these characters may have different code values, and there are no
+code points greater than 255.
+.
+.
+.SH "CHARACTERS AND METACHARACTERS"
+.rs
+.sp
+A regular expression is a pattern that is matched against a subject string from
+left to right. Most characters stand for themselves in a pattern, and match the
+corresponding characters in the subject. As a trivial example, the pattern
+.sp
+  The quick brown fox
+.sp
+matches a portion of a subject string that is identical to itself. When
+caseless matching is specified (the PCRE_CASELESS option), letters are matched
+independently of case. In a UTF mode, PCRE always understands the concept of
+case for characters whose values are less than 128, so caseless matching is
+always possible. For characters with higher values, the concept of case is
+supported if PCRE is compiled with Unicode property support, but not otherwise.
+If you want to use caseless matching for characters 128 and above, you must
+ensure that PCRE is compiled with Unicode property support as well as with
+UTF support.
+.P
+The power of regular expressions comes from the ability to include alternatives
+and repetitions in the pattern. These are encoded in the pattern by the use of
+\fImetacharacters\fP, which do not stand for themselves but instead are
+interpreted in some special way.
+.P
+There are two different sets of metacharacters: those that are recognized
+anywhere in the pattern except within square brackets, and those that are
+recognized within square brackets. Outside square brackets, the metacharacters
+are as follows:
+.sp
+  \e      general escape character with several uses
+  ^      assert start of string (or line, in multiline mode)
+  $      assert end of string (or line, in multiline mode)
+  .      match any character except newline (by default)
+  [      start character class definition
+  |      start of alternative branch
+  (      start subpattern
+  )      end subpattern
+  ?      extends the meaning of (
+         also 0 or 1 quantifier
+         also quantifier minimizer
+  *      0 or more quantifier
+  +      1 or more quantifier
+         also "possessive quantifier"
+  {      start min/max quantifier
+.sp
+Part of a pattern that is in square brackets is called a "character class". In
+a character class the only metacharacters are:
+.sp
+  \e      general escape character
+  ^      negate the class, but only if the first character
+  -      indicates character range
+.\" JOIN
+  [      POSIX character class (only if followed by POSIX
+           syntax)
+  ]      terminates the character class
+.sp
+The following sections describe the use of each of the metacharacters.
+.
+.
+.SH BACKSLASH
+.rs
+.sp
+The backslash character has several uses. Firstly, if it is followed by a
+character that is not a number or a letter, it takes away any special meaning
+that character may have. This use of backslash as an escape character applies
+both inside and outside character classes.
+.P
+For example, if you want to match a * character, you write \e* in the pattern.
+This escaping action applies whether or not the following character would
+otherwise be interpreted as a metacharacter, so it is always safe to precede a
+non-alphanumeric with backslash to specify that it stands for itself. In
+particular, if you want to match a backslash, you write \e\e.
+.P
+In a UTF mode, only ASCII numbers and letters have any special meaning after a
+backslash. All other characters (in particular, those whose codepoints are
+greater than 127) are treated as literals.
+.P
+If a pattern is compiled with the PCRE_EXTENDED option, most white space in the
+pattern (other than in a character class), and characters between a # outside a
+character class and the next newline, inclusive, are ignored. An escaping
+backslash can be used to include a white space or # character as part of the
+pattern.
+.P
+If you want to remove the special meaning from a sequence of characters, you
+can do so by putting them between \eQ and \eE. This is different from Perl in
+that $ and @ are handled as literals in \eQ...\eE sequences in PCRE, whereas in
+Perl, $ and @ cause variable interpolation. Note the following examples:
+.sp
+  Pattern            PCRE matches   Perl matches
+.sp
+.\" JOIN
+  \eQabc$xyz\eE        abc$xyz        abc followed by the
+                                      contents of $xyz
+  \eQabc\e$xyz\eE       abc\e$xyz       abc\e$xyz
+  \eQabc\eE\e$\eQxyz\eE   abc$xyz        abc$xyz
+.sp
+The \eQ...\eE sequence is recognized both inside and outside character classes.
+An isolated \eE that is not preceded by \eQ is ignored. If \eQ is not followed
+by \eE later in the pattern, the literal interpretation continues to the end of
+the pattern (that is, \eE is assumed at the end). If the isolated \eQ is inside
+a character class, this causes an error, because the character class is not
+terminated.
+.
+.
+.\" HTML <a name="digitsafterbackslash"></a>
+.SS "Non-printing characters"
+.rs
+.sp
+A second use of backslash provides a way of encoding non-printing characters
+in patterns in a visible manner. There is no restriction on the appearance of
+non-printing characters, apart from the binary zero that terminates a pattern,
+but when a pattern is being prepared by text editing, it is often easier to use
+one of the following escape sequences than the binary character it represents:
+.sp
+  \ea        alarm, that is, the BEL character (hex 07)
+  \ecx       "control-x", where x is any ASCII character
+  \ee        escape (hex 1B)
+  \ef        form feed (hex 0C)
+  \en        linefeed (hex 0A)
+  \er        carriage return (hex 0D)
+  \et        tab (hex 09)
+  \e0dd      character with octal code 0dd
+  \eddd      character with octal code ddd, or back reference
+  \eo{ddd..} character with octal code ddd..
+  \exhh      character with hex code hh
+  \ex{hhh..} character with hex code hhh.. (non-JavaScript mode)
+  \euhhhh    character with hex code hhhh (JavaScript mode only)
+.sp
+The precise effect of \ecx on ASCII characters is as follows: if x is a lower
+case letter, it is converted to upper case. Then bit 6 of the character (hex
+40) is inverted. Thus \ecA to \ecZ become hex 01 to hex 1A (A is 41, Z is 5A),
+but \ec{ becomes hex 3B ({ is 7B), and \ec; becomes hex 7B (; is 3B). If the
+data item (byte or 16-bit value) following \ec has a value greater than 127, a
+compile-time error occurs. This locks out non-ASCII characters in all modes.
+.P
+The \ec facility was designed for use with ASCII characters, but with the
+extension to Unicode it is even less useful than it once was. It is, however,
+recognized when PCRE is compiled in EBCDIC mode, where data items are always
+bytes. In this mode, all values are valid after \ec. If the next character is a
+lower case letter, it is converted to upper case. Then the 0xc0 bits of the
+byte are inverted. Thus \ecA becomes hex 01, as in ASCII (A is C1), but because
+the EBCDIC letters are disjoint, \ecZ becomes hex 29 (Z is E9), and other
+characters also generate different values.
+.P
+After \e0 up to two further octal digits are read. If there are fewer than two
+digits, just those that are present are used. Thus the sequence \e0\ex\e07
+specifies two binary zeros followed by a BEL character (code value 7). Make
+sure you supply two digits after the initial zero if the pattern character that
+follows is itself an octal digit.
+.P
+The escape \eo must be followed by a sequence of octal digits, enclosed in
+braces. An error occurs if this is not the case. This escape is a recent
+addition to Perl; it provides way of specifying character code points as octal
+numbers greater than 0777, and it also allows octal numbers and back references
+to be unambiguously specified.
+.P
+For greater clarity and unambiguity, it is best to avoid following \e by a
+digit greater than zero. Instead, use \eo{} or \ex{} to specify character
+numbers, and \eg{} to specify back references. The following paragraphs
+describe the old, ambiguous syntax.
+.P
+The handling of a backslash followed by a digit other than 0 is complicated,
+and Perl has changed in recent releases, causing PCRE also to change. Outside a
+character class, PCRE reads the digit and any following digits as a decimal
+number. If the number is less than 8, or if there have been at least that many
+previous capturing left parentheses in the expression, the entire sequence is
+taken as a \fIback reference\fP. A description of how this works is given
+.\" HTML <a href="#backreferences">
+.\" </a>
+later,
+.\"
+following the discussion of
+.\" HTML <a href="#subpattern">
+.\" </a>
+parenthesized subpatterns.
+.\"
+.P
+Inside a character class, or if the decimal number following \e is greater than
+7 and there have not been that many capturing subpatterns, PCRE handles \e8 and
+\e9 as the literal characters "8" and "9", and otherwise re-reads up to three
+octal digits following the backslash, using them to generate a data character.
+Any subsequent digits stand for themselves. For example:
+.sp
+  \e040   is another way of writing an ASCII space
+.\" JOIN
+  \e40    is the same, provided there are fewer than 40
+            previous capturing subpatterns
+  \e7     is always a back reference
+.\" JOIN
+  \e11    might be a back reference, or another way of
+            writing a tab
+  \e011   is always a tab
+  \e0113  is a tab followed by the character "3"
+.\" JOIN
+  \e113   might be a back reference, otherwise the
+            character with octal code 113
+.\" JOIN
+  \e377   might be a back reference, otherwise
+            the value 255 (decimal)
+.\" JOIN
+  \e81    is either a back reference, or the two
+            characters "8" and "1"
+.sp
+Note that octal values of 100 or greater that are specified using this syntax
+must not be introduced by a leading zero, because no more than three octal
+digits are ever read.
+.P
+By default, after \ex that is not followed by {, from zero to two hexadecimal
+digits are read (letters can be in upper or lower case). Any number of
+hexadecimal digits may appear between \ex{ and }. If a character other than
+a hexadecimal digit appears between \ex{ and }, or if there is no terminating
+}, an error occurs.
+.P
+If the PCRE_JAVASCRIPT_COMPAT option is set, the interpretation of \ex is
+as just described only when it is followed by two hexadecimal digits.
+Otherwise, it matches a literal "x" character. In JavaScript mode, support for
+code points greater than 256 is provided by \eu, which must be followed by
+four hexadecimal digits; otherwise it matches a literal "u" character.
+.P
+Characters whose value is less than 256 can be defined by either of the two
+syntaxes for \ex (or by \eu in JavaScript mode). There is no difference in the
+way they are handled. For example, \exdc is exactly the same as \ex{dc} (or
+\eu00dc in JavaScript mode).
+.
+.
+.SS "Constraints on character values"
+.rs
+.sp
+Characters that are specified using octal or hexadecimal numbers are
+limited to certain values, as follows:
+.sp
+  8-bit non-UTF mode    less than 0x100
+  8-bit UTF-8 mode      less than 0x10ffff and a valid codepoint
+  16-bit non-UTF mode   less than 0x10000
+  16-bit UTF-16 mode    less than 0x10ffff and a valid codepoint
+  32-bit non-UTF mode   less than 0x100000000
+  32-bit UTF-32 mode    less than 0x10ffff and a valid codepoint
+.sp
+Invalid Unicode codepoints are the range 0xd800 to 0xdfff (the so-called
+"surrogate" codepoints), and 0xffef.
+.
+.
+.SS "Escape sequences in character classes"
+.rs
+.sp
+All the sequences that define a single character value can be used both inside
+and outside character classes. In addition, inside a character class, \eb is
+interpreted as the backspace character (hex 08).
+.P
+\eN is not allowed in a character class. \eB, \eR, and \eX are not special
+inside a character class. Like other unrecognized escape sequences, they are
+treated as the literal characters "B", "R", and "X" by default, but cause an
+error if the PCRE_EXTRA option is set. Outside a character class, these
+sequences have different meanings.
+.
+.
+.SS "Unsupported escape sequences"
+.rs
+.sp
+In Perl, the sequences \el, \eL, \eu, and \eU are recognized by its string
+handler and used to modify the case of following characters. By default, PCRE
+does not support these escape sequences. However, if the PCRE_JAVASCRIPT_COMPAT
+option is set, \eU matches a "U" character, and \eu can be used to define a
+character by code point, as described in the previous section.
+.
+.
+.SS "Absolute and relative back references"
+.rs
+.sp
+The sequence \eg followed by an unsigned or a negative number, optionally
+enclosed in braces, is an absolute or relative back reference. A named back
+reference can be coded as \eg{name}. Back references are discussed
+.\" HTML <a href="#backreferences">
+.\" </a>
+later,
+.\"
+following the discussion of
+.\" HTML <a href="#subpattern">
+.\" </a>
+parenthesized subpatterns.
+.\"
+.
+.
+.SS "Absolute and relative subroutine calls"
+.rs
+.sp
+For compatibility with Oniguruma, the non-Perl syntax \eg followed by a name or
+a number enclosed either in angle brackets or single quotes, is an alternative
+syntax for referencing a subpattern as a "subroutine". Details are discussed
+.\" HTML <a href="#onigurumasubroutines">
+.\" </a>
+later.
+.\"
+Note that \eg{...} (Perl syntax) and \eg<...> (Oniguruma syntax) are \fInot\fP
+synonymous. The former is a back reference; the latter is a
+.\" HTML <a href="#subpatternsassubroutines">
+.\" </a>
+subroutine
+.\"
+call.
+.
+.
+.\" HTML <a name="genericchartypes"></a>
+.SS "Generic character types"
+.rs
+.sp
+Another use of backslash is for specifying generic character types:
+.sp
+  \ed     any decimal digit
+  \eD     any character that is not a decimal digit
+  \eh     any horizontal white space character
+  \eH     any character that is not a horizontal white space character
+  \es     any white space character
+  \eS     any character that is not a white space character
+  \ev     any vertical white space character
+  \eV     any character that is not a vertical white space character
+  \ew     any "word" character
+  \eW     any "non-word" character
+.sp
+There is also the single sequence \eN, which matches a non-newline character.
+This is the same as
+.\" HTML <a href="#fullstopdot">
+.\" </a>
+the "." metacharacter
+.\"
+when PCRE_DOTALL is not set. Perl also uses \eN to match characters by name;
+PCRE does not support this.
+.P
+Each pair of lower and upper case escape sequences partitions the complete set
+of characters into two disjoint sets. Any given character matches one, and only
+one, of each pair. The sequences can appear both inside and outside character
+classes. They each match one character of the appropriate type. If the current
+matching point is at the end of the subject string, all of them fail, because
+there is no character to match.
+.P
+For compatibility with Perl, \es did not used to match the VT character (code
+11), which made it different from the the POSIX "space" class. However, Perl
+added VT at release 5.18, and PCRE followed suit at release 8.34. The default
+\es characters are now HT (9), LF (10), VT (11), FF (12), CR (13), and space
+(32), which are defined as white space in the "C" locale. This list may vary if
+locale-specific matching is taking place. For example, in some locales the
+"non-breaking space" character (\exA0) is recognized as white space, and in
+others the VT character is not.
+.P
+A "word" character is an underscore or any character that is a letter or digit.
+By default, the definition of letters and digits is controlled by PCRE's
+low-valued character tables, and may vary if locale-specific matching is taking
+place (see
+.\" HTML <a href="pcreapi.html#localesupport">
+.\" </a>
+"Locale support"
+.\"
+in the
+.\" HREF
+\fBpcreapi\fP
+.\"
+page). For example, in a French locale such as "fr_FR" in Unix-like systems,
+or "french" in Windows, some character codes greater than 127 are used for
+accented letters, and these are then matched by \ew. The use of locales with
+Unicode is discouraged.
+.P
+By default, characters whose code points are greater than 127 never match \ed,
+\es, or \ew, and always match \eD, \eS, and \eW, although this may vary for
+characters in the range 128-255 when locale-specific matching is happening.
+These escape sequences retain their original meanings from before Unicode
+support was available, mainly for efficiency reasons. If PCRE is compiled with
+Unicode property support, and the PCRE_UCP option is set, the behaviour is
+changed so that Unicode properties are used to determine character types, as
+follows:
+.sp
+  \ed  any character that matches \ep{Nd} (decimal digit)
+  \es  any character that matches \ep{Z} or \eh or \ev
+  \ew  any character that matches \ep{L} or \ep{N}, plus underscore
+.sp
+The upper case escapes match the inverse sets of characters. Note that \ed
+matches only decimal digits, whereas \ew matches any Unicode digit, as well as
+any Unicode letter, and underscore. Note also that PCRE_UCP affects \eb, and
+\eB because they are defined in terms of \ew and \eW. Matching these sequences
+is noticeably slower when PCRE_UCP is set.
+.P
+The sequences \eh, \eH, \ev, and \eV are features that were added to Perl at
+release 5.10. In contrast to the other sequences, which match only ASCII
+characters by default, these always match certain high-valued code points,
+whether or not PCRE_UCP is set. The horizontal space characters are:
+.sp
+  U+0009     Horizontal tab (HT)
+  U+0020     Space
+  U+00A0     Non-break space
+  U+1680     Ogham space mark
+  U+180E     Mongolian vowel separator
+  U+2000     En quad
+  U+2001     Em quad
+  U+2002     En space
+  U+2003     Em space
+  U+2004     Three-per-em space
+  U+2005     Four-per-em space
+  U+2006     Six-per-em space
+  U+2007     Figure space
+  U+2008     Punctuation space
+  U+2009     Thin space
+  U+200A     Hair space
+  U+202F     Narrow no-break space
+  U+205F     Medium mathematical space
+  U+3000     Ideographic space
+.sp
+The vertical space characters are:
+.sp
+  U+000A     Linefeed (LF)
+  U+000B     Vertical tab (VT)
+  U+000C     Form feed (FF)
+  U+000D     Carriage return (CR)
+  U+0085     Next line (NEL)
+  U+2028     Line separator
+  U+2029     Paragraph separator
+.sp
+In 8-bit, non-UTF-8 mode, only the characters with codepoints less than 256 are
+relevant.
+.
+.
+.\" HTML <a name="newlineseq"></a>
+.SS "Newline sequences"
+.rs
+.sp
+Outside a character class, by default, the escape sequence \eR matches any
+Unicode newline sequence. In 8-bit non-UTF-8 mode \eR is equivalent to the
+following:
+.sp
+  (?>\er\en|\en|\ex0b|\ef|\er|\ex85)
+.sp
+This is an example of an "atomic group", details of which are given
+.\" HTML <a href="#atomicgroup">
+.\" </a>
+below.
+.\"
+This particular group matches either the two-character sequence CR followed by
+LF, or one of the single characters LF (linefeed, U+000A), VT (vertical tab,
+U+000B), FF (form feed, U+000C), CR (carriage return, U+000D), or NEL (next
+line, U+0085). The two-character sequence is treated as a single unit that
+cannot be split.
+.P
+In other modes, two additional characters whose codepoints are greater than 255
+are added: LS (line separator, U+2028) and PS (paragraph separator, U+2029).
+Unicode character property support is not needed for these characters to be
+recognized.
+.P
+It is possible to restrict \eR to match only CR, LF, or CRLF (instead of the
+complete set of Unicode line endings) by setting the option PCRE_BSR_ANYCRLF
+either at compile time or when the pattern is matched. (BSR is an abbrevation
+for "backslash R".) This can be made the default when PCRE is built; if this is
+the case, the other behaviour can be requested via the PCRE_BSR_UNICODE option.
+It is also possible to specify these settings by starting a pattern string with
+one of the following sequences:
+.sp
+  (*BSR_ANYCRLF)   CR, LF, or CRLF only
+  (*BSR_UNICODE)   any Unicode newline sequence
+.sp
+These override the default and the options given to the compiling function, but
+they can themselves be overridden by options given to a matching function. Note
+that these special settings, which are not Perl-compatible, are recognized only
+at the very start of a pattern, and that they must be in upper case. If more
+than one of them is present, the last one is used. They can be combined with a
+change of newline convention; for example, a pattern can start with:
+.sp
+  (*ANY)(*BSR_ANYCRLF)
+.sp
+They can also be combined with the (*UTF8), (*UTF16), (*UTF32), (*UTF) or
+(*UCP) special sequences. Inside a character class, \eR is treated as an
+unrecognized escape sequence, and so matches the letter "R" by default, but
+causes an error if PCRE_EXTRA is set.
+.
+.
+.\" HTML <a name="uniextseq"></a>
+.SS Unicode character properties
+.rs
+.sp
+When PCRE is built with Unicode character property support, three additional
+escape sequences that match characters with specific properties are available.
+When in 8-bit non-UTF-8 mode, these sequences are of course limited to testing
+characters whose codepoints are less than 256, but they do work in this mode.
+The extra escape sequences are:
+.sp
+  \ep{\fIxx\fP}   a character with the \fIxx\fP property
+  \eP{\fIxx\fP}   a character without the \fIxx\fP property
+  \eX       a Unicode extended grapheme cluster
+.sp
+The property names represented by \fIxx\fP above are limited to the Unicode
+script names, the general category properties, "Any", which matches any
+character (including newline), and some special PCRE properties (described
+in the
+.\" HTML <a href="#extraprops">
+.\" </a>
+next section).
+.\"
+Other Perl properties such as "InMusicalSymbols" are not currently supported by
+PCRE. Note that \eP{Any} does not match any characters, so always causes a
+match failure.
+.P
+Sets of Unicode characters are defined as belonging to certain scripts. A
+character from one of these sets can be matched using a script name. For
+example:
+.sp
+  \ep{Greek}
+  \eP{Han}
+.sp
+Those that are not part of an identified script are lumped together as
+"Common". The current list of scripts is:
+.P
+Arabic,
+Armenian,
+Avestan,
+Balinese,
+Bamum,
+Batak,
+Bengali,
+Bopomofo,
+Brahmi,
+Braille,
+Buginese,
+Buhid,
+Canadian_Aboriginal,
+Carian,
+Chakma,
+Cham,
+Cherokee,
+Common,
+Coptic,
+Cuneiform,
+Cypriot,
+Cyrillic,
+Deseret,
+Devanagari,
+Egyptian_Hieroglyphs,
+Ethiopic,
+Georgian,
+Glagolitic,
+Gothic,
+Greek,
+Gujarati,
+Gurmukhi,
+Han,
+Hangul,
+Hanunoo,
+Hebrew,
+Hiragana,
+Imperial_Aramaic,
+Inherited,
+Inscriptional_Pahlavi,
+Inscriptional_Parthian,
+Javanese,
+Kaithi,
+Kannada,
+Katakana,
+Kayah_Li,
+Kharoshthi,
+Khmer,
+Lao,
+Latin,
+Lepcha,
+Limbu,
+Linear_B,
+Lisu,
+Lycian,
+Lydian,
+Malayalam,
+Mandaic,
+Meetei_Mayek,
+Meroitic_Cursive,
+Meroitic_Hieroglyphs,
+Miao,
+Mongolian,
+Myanmar,
+New_Tai_Lue,
+Nko,
+Ogham,
+Old_Italic,
+Old_Persian,
+Old_South_Arabian,
+Old_Turkic,
+Ol_Chiki,
+Oriya,
+Osmanya,
+Phags_Pa,
+Phoenician,
+Rejang,
+Runic,
+Samaritan,
+Saurashtra,
+Sharada,
+Shavian,
+Sinhala,
+Sora_Sompeng,
+Sundanese,
+Syloti_Nagri,
+Syriac,
+Tagalog,
+Tagbanwa,
+Tai_Le,
+Tai_Tham,
+Tai_Viet,
+Takri,
+Tamil,
+Telugu,
+Thaana,
+Thai,
+Tibetan,
+Tifinagh,
+Ugaritic,
+Vai,
+Yi.
+.P
+Each character has exactly one Unicode general category property, specified by
+a two-letter abbreviation. For compatibility with Perl, negation can be
+specified by including a circumflex between the opening brace and the property
+name. For example, \ep{^Lu} is the same as \eP{Lu}.
+.P
+If only one letter is specified with \ep or \eP, it includes all the general
+category properties that start with that letter. In this case, in the absence
+of negation, the curly brackets in the escape sequence are optional; these two
+examples have the same effect:
+.sp
+  \ep{L}
+  \epL
+.sp
+The following general category property codes are supported:
+.sp
+  C     Other
+  Cc    Control
+  Cf    Format
+  Cn    Unassigned
+  Co    Private use
+  Cs    Surrogate
+.sp
+  L     Letter
+  Ll    Lower case letter
+  Lm    Modifier letter
+  Lo    Other letter
+  Lt    Title case letter
+  Lu    Upper case letter
+.sp
+  M     Mark
+  Mc    Spacing mark
+  Me    Enclosing mark
+  Mn    Non-spacing mark
+.sp
+  N     Number
+  Nd    Decimal number
+  Nl    Letter number
+  No    Other number
+.sp
+  P     Punctuation
+  Pc    Connector punctuation
+  Pd    Dash punctuation
+  Pe    Close punctuation
+  Pf    Final punctuation
+  Pi    Initial punctuation
+  Po    Other punctuation
+  Ps    Open punctuation
+.sp
+  S     Symbol
+  Sc    Currency symbol
+  Sk    Modifier symbol
+  Sm    Mathematical symbol
+  So    Other symbol
+.sp
+  Z     Separator
+  Zl    Line separator
+  Zp    Paragraph separator
+  Zs    Space separator
+.sp
+The special property L& is also supported: it matches a character that has
+the Lu, Ll, or Lt property, in other words, a letter that is not classified as
+a modifier or "other".
+.P
+The Cs (Surrogate) property applies only to characters in the range U+D800 to
+U+DFFF. Such characters are not valid in Unicode strings and so
+cannot be tested by PCRE, unless UTF validity checking has been turned off
+(see the discussion of PCRE_NO_UTF8_CHECK, PCRE_NO_UTF16_CHECK and
+PCRE_NO_UTF32_CHECK in the
+.\" HREF
+\fBpcreapi\fP
+.\"
+page). Perl does not support the Cs property.
+.P
+The long synonyms for property names that Perl supports (such as \ep{Letter})
+are not supported by PCRE, nor is it permitted to prefix any of these
+properties with "Is".
+.P
+No character that is in the Unicode table has the Cn (unassigned) property.
+Instead, this property is assumed for any code point that is not in the
+Unicode table.
+.P
+Specifying caseless matching does not affect these escape sequences. For
+example, \ep{Lu} always matches only upper case letters. This is different from
+the behaviour of current versions of Perl.
+.P
+Matching characters by Unicode property is not fast, because PCRE has to do a
+multistage table lookup in order to find a character's property. That is why
+the traditional escape sequences such as \ed and \ew do not use Unicode
+properties in PCRE by default, though you can make them do so by setting the
+PCRE_UCP option or by starting the pattern with (*UCP).
+.
+.
+.SS Extended grapheme clusters
+.rs
+.sp
+The \eX escape matches any number of Unicode characters that form an "extended
+grapheme cluster", and treats the sequence as an atomic group
+.\" HTML <a href="#atomicgroup">
+.\" </a>
+(see below).
+.\"
+Up to and including release 8.31, PCRE matched an earlier, simpler definition
+that was equivalent to
+.sp
+  (?>\ePM\epM*)
+.sp
+That is, it matched a character without the "mark" property, followed by zero
+or more characters with the "mark" property. Characters with the "mark"
+property are typically non-spacing accents that affect the preceding character.
+.P
+This simple definition was extended in Unicode to include more complicated
+kinds of composite character by giving each character a grapheme breaking
+property, and creating rules that use these properties to define the boundaries
+of extended grapheme clusters. In releases of PCRE later than 8.31, \eX matches
+one of these clusters.
+.P
+\eX always matches at least one character. Then it decides whether to add
+additional characters according to the following rules for ending a cluster:
+.P
+1. End at the end of the subject string.
+.P
+2. Do not end between CR and LF; otherwise end after any control character.
+.P
+3. Do not break Hangul (a Korean script) syllable sequences. Hangul characters
+are of five types: L, V, T, LV, and LVT. An L character may be followed by an
+L, V, LV, or LVT character; an LV or V character may be followed by a V or T
+character; an LVT or T character may be follwed only by a T character.
+.P
+4. Do not end before extending characters or spacing marks. Characters with
+the "mark" property always have the "extend" grapheme breaking property.
+.P
+5. Do not end after prepend characters.
+.P
+6. Otherwise, end the cluster.
+.
+.
+.\" HTML <a name="extraprops"></a>
+.SS PCRE's additional properties
+.rs
+.sp
+As well as the standard Unicode properties described above, PCRE supports four
+more that make it possible to convert traditional escape sequences such as \ew
+and \es to use Unicode properties. PCRE uses these non-standard, non-Perl
+properties internally when PCRE_UCP is set. However, they may also be used
+explicitly. These properties are:
+.sp
+  Xan   Any alphanumeric character
+  Xps   Any POSIX space character
+  Xsp   Any Perl space character
+  Xwd   Any Perl "word" character
+.sp
+Xan matches characters that have either the L (letter) or the N (number)
+property. Xps matches the characters tab, linefeed, vertical tab, form feed, or
+carriage return, and any other character that has the Z (separator) property.
+Xsp is the same as Xps; it used to exclude vertical tab, for Perl
+compatibility, but Perl changed, and so PCRE followed at release 8.34. Xwd
+matches the same characters as Xan, plus underscore.
+.P
+There is another non-standard property, Xuc, which matches any character that
+can be represented by a Universal Character Name in C++ and other programming
+languages. These are the characters $, @, ` (grave accent), and all characters
+with Unicode code points greater than or equal to U+00A0, except for the
+surrogates U+D800 to U+DFFF. Note that most base (ASCII) characters are
+excluded. (Universal Character Names are of the form \euHHHH or \eUHHHHHHHH
+where H is a hexadecimal digit. Note that the Xuc property does not match these
+sequences but the characters that they represent.)
+.
+.
+.\" HTML <a name="resetmatchstart"></a>
+.SS "Resetting the match start"
+.rs
+.sp
+The escape sequence \eK causes any previously matched characters not to be
+included in the final matched sequence. For example, the pattern:
+.sp
+  foo\eKbar
+.sp
+matches "foobar", but reports that it has matched "bar". This feature is
+similar to a lookbehind assertion
+.\" HTML <a href="#lookbehind">
+.\" </a>
+(described below).
+.\"
+However, in this case, the part of the subject before the real match does not
+have to be of fixed length, as lookbehind assertions do. The use of \eK does
+not interfere with the setting of
+.\" HTML <a href="#subpattern">
+.\" </a>
+captured substrings.
+.\"
+For example, when the pattern
+.sp
+  (foo)\eKbar
+.sp
+matches "foobar", the first substring is still set to "foo".
+.P
+Perl documents that the use of \eK within assertions is "not well defined". In
+PCRE, \eK is acted upon when it occurs inside positive assertions, but is
+ignored in negative assertions. Note that when a pattern such as (?=ab\eK)
+matches, the reported start of the match can be greater than the end of the
+match.
+.
+.
+.\" HTML <a name="smallassertions"></a>
+.SS "Simple assertions"
+.rs
+.sp
+The final use of backslash is for certain simple assertions. An assertion
+specifies a condition that has to be met at a particular point in a match,
+without consuming any characters from the subject string. The use of
+subpatterns for more complicated assertions is described
+.\" HTML <a href="#bigassertions">
+.\" </a>
+below.
+.\"
+The backslashed assertions are:
+.sp
+  \eb     matches at a word boundary
+  \eB     matches when not at a word boundary
+  \eA     matches at the start of the subject
+  \eZ     matches at the end of the subject
+          also matches before a newline at the end of the subject
+  \ez     matches only at the end of the subject
+  \eG     matches at the first matching position in the subject
+.sp
+Inside a character class, \eb has a different meaning; it matches the backspace
+character. If any other of these assertions appears in a character class, by
+default it matches the corresponding literal character (for example, \eB
+matches the letter B). However, if the PCRE_EXTRA option is set, an "invalid
+escape sequence" error is generated instead.
+.P
+A word boundary is a position in the subject string where the current character
+and the previous character do not both match \ew or \eW (i.e. one matches
+\ew and the other matches \eW), or the start or end of the string if the
+first or last character matches \ew, respectively. In a UTF mode, the meanings
+of \ew and \eW can be changed by setting the PCRE_UCP option. When this is
+done, it also affects \eb and \eB. Neither PCRE nor Perl has a separate "start
+of word" or "end of word" metasequence. However, whatever follows \eb normally
+determines which it is. For example, the fragment \eba matches "a" at the start
+of a word.
+.P
+The \eA, \eZ, and \ez assertions differ from the traditional circumflex and
+dollar (described in the next section) in that they only ever match at the very
+start and end of the subject string, whatever options are set. Thus, they are
+independent of multiline mode. These three assertions are not affected by the
+PCRE_NOTBOL or PCRE_NOTEOL options, which affect only the behaviour of the
+circumflex and dollar metacharacters. However, if the \fIstartoffset\fP
+argument of \fBpcre_exec()\fP is non-zero, indicating that matching is to start
+at a point other than the beginning of the subject, \eA can never match. The
+difference between \eZ and \ez is that \eZ matches before a newline at the end
+of the string as well as at the very end, whereas \ez matches only at the end.
+.P
+The \eG assertion is true only when the current matching position is at the
+start point of the match, as specified by the \fIstartoffset\fP argument of
+\fBpcre_exec()\fP. It differs from \eA when the value of \fIstartoffset\fP is
+non-zero. By calling \fBpcre_exec()\fP multiple times with appropriate
+arguments, you can mimic Perl's /g option, and it is in this kind of
+implementation where \eG can be useful.
+.P
+Note, however, that PCRE's interpretation of \eG, as the start of the current
+match, is subtly different from Perl's, which defines it as the end of the
+previous match. In Perl, these can be different when the previously matched
+string was empty. Because PCRE does just one match at a time, it cannot
+reproduce this behaviour.
+.P
+If all the alternatives of a pattern begin with \eG, the expression is anchored
+to the starting match position, and the "anchored" flag is set in the compiled
+regular expression.
+.
+.
+.SH "CIRCUMFLEX AND DOLLAR"
+.rs
+.sp
+The circumflex and dollar metacharacters are zero-width assertions. That is,
+they test for a particular condition being true without consuming any
+characters from the subject string.
+.P
+Outside a character class, in the default matching mode, the circumflex
+character is an assertion that is true only if the current matching point is at
+the start of the subject string. If the \fIstartoffset\fP argument of
+\fBpcre_exec()\fP is non-zero, circumflex can never match if the PCRE_MULTILINE
+option is unset. Inside a character class, circumflex has an entirely different
+meaning
+.\" HTML <a href="#characterclass">
+.\" </a>
+(see below).
+.\"
+.P
+Circumflex need not be the first character of the pattern if a number of
+alternatives are involved, but it should be the first thing in each alternative
+in which it appears if the pattern is ever to match that branch. If all
+possible alternatives start with a circumflex, that is, if the pattern is
+constrained to match only at the start of the subject, it is said to be an
+"anchored" pattern. (There are also other constructs that can cause a pattern
+to be anchored.)
+.P
+The dollar character is an assertion that is true only if the current matching
+point is at the end of the subject string, or immediately before a newline at
+the end of the string (by default). Note, however, that it does not actually
+match the newline. Dollar need not be the last character of the pattern if a
+number of alternatives are involved, but it should be the last item in any
+branch in which it appears. Dollar has no special meaning in a character class.
+.P
+The meaning of dollar can be changed so that it matches only at the very end of
+the string, by setting the PCRE_DOLLAR_ENDONLY option at compile time. This
+does not affect the \eZ assertion.
+.P
+The meanings of the circumflex and dollar characters are changed if the
+PCRE_MULTILINE option is set. When this is the case, a circumflex matches
+immediately after internal newlines as well as at the start of the subject
+string. It does not match after a newline that ends the string. A dollar
+matches before any newlines in the string, as well as at the very end, when
+PCRE_MULTILINE is set. When newline is specified as the two-character
+sequence CRLF, isolated CR and LF characters do not indicate newlines.
+.P
+For example, the pattern /^abc$/ matches the subject string "def\enabc" (where
+\en represents a newline) in multiline mode, but not otherwise. Consequently,
+patterns that are anchored in single line mode because all branches start with
+^ are not anchored in multiline mode, and a match for circumflex is possible
+when the \fIstartoffset\fP argument of \fBpcre_exec()\fP is non-zero. The
+PCRE_DOLLAR_ENDONLY option is ignored if PCRE_MULTILINE is set.
+.P
+Note that the sequences \eA, \eZ, and \ez can be used to match the start and
+end of the subject in both modes, and if all branches of a pattern start with
+\eA it is always anchored, whether or not PCRE_MULTILINE is set.
+.
+.
+.\" HTML <a name="fullstopdot"></a>
+.SH "FULL STOP (PERIOD, DOT) AND \eN"
+.rs
+.sp
+Outside a character class, a dot in the pattern matches any one character in
+the subject string except (by default) a character that signifies the end of a
+line.
+.P
+When a line ending is defined as a single character, dot never matches that
+character; when the two-character sequence CRLF is used, dot does not match CR
+if it is immediately followed by LF, but otherwise it matches all characters
+(including isolated CRs and LFs). When any Unicode line endings are being
+recognized, dot does not match CR or LF or any of the other line ending
+characters.
+.P
+The behaviour of dot with regard to newlines can be changed. If the PCRE_DOTALL
+option is set, a dot matches any one character, without exception. If the
+two-character sequence CRLF is present in the subject string, it takes two dots
+to match it.
+.P
+The handling of dot is entirely independent of the handling of circumflex and
+dollar, the only relationship being that they both involve newlines. Dot has no
+special meaning in a character class.
+.P
+The escape sequence \eN behaves like a dot, except that it is not affected by
+the PCRE_DOTALL option. In other words, it matches any character except one
+that signifies the end of a line. Perl also uses \eN to match characters by
+name; PCRE does not support this.
+.
+.
+.SH "MATCHING A SINGLE DATA UNIT"
+.rs
+.sp
+Outside a character class, the escape sequence \eC matches any one data unit,
+whether or not a UTF mode is set. In the 8-bit library, one data unit is one
+byte; in the 16-bit library it is a 16-bit unit; in the 32-bit library it is
+a 32-bit unit. Unlike a dot, \eC always
+matches line-ending characters. The feature is provided in Perl in order to
+match individual bytes in UTF-8 mode, but it is unclear how it can usefully be
+used. Because \eC breaks up characters into individual data units, matching one
+unit with \eC in a UTF mode means that the rest of the string may start with a
+malformed UTF character. This has undefined results, because PCRE assumes that
+it is dealing with valid UTF strings (and by default it checks this at the
+start of processing unless the PCRE_NO_UTF8_CHECK, PCRE_NO_UTF16_CHECK or
+PCRE_NO_UTF32_CHECK option is used).
+.P
+PCRE does not allow \eC to appear in lookbehind assertions
+.\" HTML <a href="#lookbehind">
+.\" </a>
+(described below)
+.\"
+in a UTF mode, because this would make it impossible to calculate the length of
+the lookbehind.
+.P
+In general, the \eC escape sequence is best avoided. However, one
+way of using it that avoids the problem of malformed UTF characters is to use a
+lookahead to check the length of the next character, as in this pattern, which
+could be used with a UTF-8 string (ignore white space and line breaks):
+.sp
+  (?| (?=[\ex00-\ex7f])(\eC) |
+      (?=[\ex80-\ex{7ff}])(\eC)(\eC) |
+      (?=[\ex{800}-\ex{ffff}])(\eC)(\eC)(\eC) |
+      (?=[\ex{10000}-\ex{1fffff}])(\eC)(\eC)(\eC)(\eC))
+.sp
+A group that starts with (?| resets the capturing parentheses numbers in each
+alternative (see
+.\" HTML <a href="#dupsubpatternnumber">
+.\" </a>
+"Duplicate Subpattern Numbers"
+.\"
+below). The assertions at the start of each branch check the next UTF-8
+character for values whose encoding uses 1, 2, 3, or 4 bytes, respectively. The
+character's individual bytes are then captured by the appropriate number of
+groups.
+.
+.
+.\" HTML <a name="characterclass"></a>
+.SH "SQUARE BRACKETS AND CHARACTER CLASSES"
+.rs
+.sp
+An opening square bracket introduces a character class, terminated by a closing
+square bracket. A closing square bracket on its own is not special by default.
+However, if the PCRE_JAVASCRIPT_COMPAT option is set, a lone closing square
+bracket causes a compile-time error. If a closing square bracket is required as
+a member of the class, it should be the first data character in the class
+(after an initial circumflex, if present) or escaped with a backslash.
+.P
+A character class matches a single character in the subject. In a UTF mode, the
+character may be more than one data unit long. A matched character must be in
+the set of characters defined by the class, unless the first character in the
+class definition is a circumflex, in which case the subject character must not
+be in the set defined by the class. If a circumflex is actually required as a
+member of the class, ensure it is not the first character, or escape it with a
+backslash.
+.P
+For example, the character class [aeiou] matches any lower case vowel, while
+[^aeiou] matches any character that is not a lower case vowel. Note that a
+circumflex is just a convenient notation for specifying the characters that
+are in the class by enumerating those that are not. A class that starts with a
+circumflex is not an assertion; it still consumes a character from the subject
+string, and therefore it fails if the current pointer is at the end of the
+string.
+.P
+In UTF-8 (UTF-16, UTF-32) mode, characters with values greater than 255 (0xffff)
+can be included in a class as a literal string of data units, or by using the
+\ex{ escaping mechanism.
+.P
+When caseless matching is set, any letters in a class represent both their
+upper case and lower case versions, so for example, a caseless [aeiou] matches
+"A" as well as "a", and a caseless [^aeiou] does not match "A", whereas a
+caseful version would. In a UTF mode, PCRE always understands the concept of
+case for characters whose values are less than 128, so caseless matching is
+always possible. For characters with higher values, the concept of case is
+supported if PCRE is compiled with Unicode property support, but not otherwise.
+If you want to use caseless matching in a UTF mode for characters 128 and
+above, you must ensure that PCRE is compiled with Unicode property support as
+well as with UTF support.
+.P
+Characters that might indicate line breaks are never treated in any special way
+when matching character classes, whatever line-ending sequence is in use, and
+whatever setting of the PCRE_DOTALL and PCRE_MULTILINE options is used. A class
+such as [^a] always matches one of these characters.
+.P
+The minus (hyphen) character can be used to specify a range of characters in a
+character class. For example, [d-m] matches any letter between d and m,
+inclusive. If a minus character is required in a class, it must be escaped with
+a backslash or appear in a position where it cannot be interpreted as
+indicating a range, typically as the first or last character in the class, or
+immediately after a range. For example, [b-d-z] matches letters in the range b
+to d, a hyphen character, or z.
+.P
+It is not possible to have the literal character "]" as the end character of a
+range. A pattern such as [W-]46] is interpreted as a class of two characters
+("W" and "-") followed by a literal string "46]", so it would match "W46]" or
+"-46]". However, if the "]" is escaped with a backslash it is interpreted as
+the end of range, so [W-\e]46] is interpreted as a class containing a range
+followed by two other characters. The octal or hexadecimal representation of
+"]" can also be used to end a range.
+.P
+An error is generated if a POSIX character class (see below) or an escape
+sequence other than one that defines a single character appears at a point
+where a range ending character is expected. For example, [z-\exff] is valid,
+but [A-\ed] and [A-[:digit:]] are not.
+.P
+Ranges operate in the collating sequence of character values. They can also be
+used for characters specified numerically, for example [\e000-\e037]. Ranges
+can include any characters that are valid for the current mode.
+.P
+If a range that includes letters is used when caseless matching is set, it
+matches the letters in either case. For example, [W-c] is equivalent to
+[][\e\e^_`wxyzabc], matched caselessly, and in a non-UTF mode, if character
+tables for a French locale are in use, [\exc8-\excb] matches accented E
+characters in both cases. In UTF modes, PCRE supports the concept of case for
+characters with values greater than 128 only when it is compiled with Unicode
+property support.
+.P
+The character escape sequences \ed, \eD, \eh, \eH, \ep, \eP, \es, \eS, \ev,
+\eV, \ew, and \eW may appear in a character class, and add the characters that
+they match to the class. For example, [\edABCDEF] matches any hexadecimal
+digit. In UTF modes, the PCRE_UCP option affects the meanings of \ed, \es, \ew
+and their upper case partners, just as it does when they appear outside a
+character class, as described in the section entitled
+.\" HTML <a href="#genericchartypes">
+.\" </a>
+"Generic character types"
+.\"
+above. The escape sequence \eb has a different meaning inside a character
+class; it matches the backspace character. The sequences \eB, \eN, \eR, and \eX
+are not special inside a character class. Like any other unrecognized escape
+sequences, they are treated as the literal characters "B", "N", "R", and "X" by
+default, but cause an error if the PCRE_EXTRA option is set.
+.P
+A circumflex can conveniently be used with the upper case character types to
+specify a more restricted set of characters than the matching lower case type.
+For example, the class [^\eW_] matches any letter or digit, but not underscore,
+whereas [\ew] includes underscore. A positive character class should be read as
+"something OR something OR ..." and a negative class as "NOT something AND NOT
+something AND NOT ...".
+.P
+The only metacharacters that are recognized in character classes are backslash,
+hyphen (only where it can be interpreted as specifying a range), circumflex
+(only at the start), opening square bracket (only when it can be interpreted as
+introducing a POSIX class name, or for a special compatibility feature - see
+the next two sections), and the terminating closing square bracket. However,
+escaping other non-alphanumeric characters does no harm.
+.
+.
+.SH "POSIX CHARACTER CLASSES"
+.rs
+.sp
+Perl supports the POSIX notation for character classes. This uses names
+enclosed by [: and :] within the enclosing square brackets. PCRE also supports
+this notation. For example,
+.sp
+  [01[:alpha:]%]
+.sp
+matches "0", "1", any alphabetic character, or "%". The supported class names
+are:
+.sp
+  alnum    letters and digits
+  alpha    letters
+  ascii    character codes 0 - 127
+  blank    space or tab only
+  cntrl    control characters
+  digit    decimal digits (same as \ed)
+  graph    printing characters, excluding space
+  lower    lower case letters
+  print    printing characters, including space
+  punct    printing characters, excluding letters and digits and space
+  space    white space (the same as \es from PCRE 8.34)
+  upper    upper case letters
+  word     "word" characters (same as \ew)
+  xdigit   hexadecimal digits
+.sp
+The default "space" characters are HT (9), LF (10), VT (11), FF (12), CR (13),
+and space (32). If locale-specific matching is taking place, the list of space
+characters may be different; there may be fewer or more of them. "Space" used
+to be different to \es, which did not include VT, for Perl compatibility.
+However, Perl changed at release 5.18, and PCRE followed at release 8.34.
+"Space" and \es now match the same set of characters.
+.P
+The name "word" is a Perl extension, and "blank" is a GNU extension from Perl
+5.8. Another Perl extension is negation, which is indicated by a ^ character
+after the colon. For example,
+.sp
+  [12[:^digit:]]
+.sp
+matches "1", "2", or any non-digit. PCRE (and Perl) also recognize the POSIX
+syntax [.ch.] and [=ch=] where "ch" is a "collating element", but these are not
+supported, and an error is given if they are encountered.
+.P
+By default, characters with values greater than 128 do not match any of the
+POSIX character classes. However, if the PCRE_UCP option is passed to
+\fBpcre_compile()\fP, some of the classes are changed so that Unicode character
+properties are used. This is achieved by replacing certain POSIX classes by
+other sequences, as follows:
+.sp
+  [:alnum:]  becomes  \ep{Xan}
+  [:alpha:]  becomes  \ep{L}
+  [:blank:]  becomes  \eh
+  [:digit:]  becomes  \ep{Nd}
+  [:lower:]  becomes  \ep{Ll}
+  [:space:]  becomes  \ep{Xps}
+  [:upper:]  becomes  \ep{Lu}
+  [:word:]   becomes  \ep{Xwd}
+.sp
+Negated versions, such as [:^alpha:] use \eP instead of \ep. Three other POSIX
+classes are handled specially in UCP mode:
+.TP 10
+[:graph:]
+This matches characters that have glyphs that mark the page when printed. In
+Unicode property terms, it matches all characters with the L, M, N, P, S, or Cf
+properties, except for:
+.sp
+  U+061C           Arabic Letter Mark
+  U+180E           Mongolian Vowel Separator
+  U+2066 - U+2069  Various "isolate"s
+.sp
+.TP 10
+[:print:]
+This matches the same characters as [:graph:] plus space characters that are
+not controls, that is, characters with the Zs property.
+.TP 10
+[:punct:]
+This matches all characters that have the Unicode P (punctuation) property,
+plus those characters whose code points are less than 128 that have the S
+(Symbol) property.
+.P
+The other POSIX classes are unchanged, and match only characters with code
+points less than 128.
+.
+.
+.SH "COMPATIBILITY FEATURE FOR WORD BOUNDARIES"
+.rs
+.sp
+In the POSIX.2 compliant library that was included in 4.4BSD Unix, the ugly
+syntax [[:<:]] and [[:>:]] is used for matching "start of word" and "end of
+word". PCRE treats these items as follows:
+.sp
+  [[:<:]]  is converted to  \eb(?=\ew)
+  [[:>:]]  is converted to  \eb(?<=\ew)
+.sp
+Only these exact character sequences are recognized. A sequence such as
+[a[:<:]b] provokes error for an unrecognized POSIX class name. This support is
+not compatible with Perl. It is provided to help migrations from other
+environments, and is best not used in any new patterns. Note that \eb matches
+at the start and the end of a word (see
+.\" HTML <a href="#smallassertions">
+.\" </a>
+"Simple assertions"
+.\"
+above), and in a Perl-style pattern the preceding or following character
+normally shows which is wanted, without the need for the assertions that are
+used above in order to give exactly the POSIX behaviour.
+.
+.
+.SH "VERTICAL BAR"
+.rs
+.sp
+Vertical bar characters are used to separate alternative patterns. For example,
+the pattern
+.sp
+  gilbert|sullivan
+.sp
+matches either "gilbert" or "sullivan". Any number of alternatives may appear,
+and an empty alternative is permitted (matching the empty string). The matching
+process tries each alternative in turn, from left to right, and the first one
+that succeeds is used. If the alternatives are within a subpattern
+.\" HTML <a href="#subpattern">
+.\" </a>
+(defined below),
+.\"
+"succeeds" means matching the rest of the main pattern as well as the
+alternative in the subpattern.
+.
+.
+.SH "INTERNAL OPTION SETTING"
+.rs
+.sp
+The settings of the PCRE_CASELESS, PCRE_MULTILINE, PCRE_DOTALL, and
+PCRE_EXTENDED options (which are Perl-compatible) can be changed from within
+the pattern by a sequence of Perl option letters enclosed between "(?" and ")".
+The option letters are
+.sp
+  i  for PCRE_CASELESS
+  m  for PCRE_MULTILINE
+  s  for PCRE_DOTALL
+  x  for PCRE_EXTENDED
+.sp
+For example, (?im) sets caseless, multiline matching. It is also possible to
+unset these options by preceding the letter with a hyphen, and a combined
+setting and unsetting such as (?im-sx), which sets PCRE_CASELESS and
+PCRE_MULTILINE while unsetting PCRE_DOTALL and PCRE_EXTENDED, is also
+permitted. If a letter appears both before and after the hyphen, the option is
+unset.
+.P
+The PCRE-specific options PCRE_DUPNAMES, PCRE_UNGREEDY, and PCRE_EXTRA can be
+changed in the same way as the Perl-compatible options by using the characters
+J, U and X respectively.
+.P
+When one of these option changes occurs at top level (that is, not inside
+subpattern parentheses), the change applies to the remainder of the pattern
+that follows. If the change is placed right at the start of a pattern, PCRE
+extracts it into the global options (and it will therefore show up in data
+extracted by the \fBpcre_fullinfo()\fP function).
+.P
+An option change within a subpattern (see below for a description of
+subpatterns) affects only that part of the subpattern that follows it, so
+.sp
+  (a(?i)b)c
+.sp
+matches abc and aBc and no other strings (assuming PCRE_CASELESS is not used).
+By this means, options can be made to have different settings in different
+parts of the pattern. Any changes made in one alternative do carry on
+into subsequent branches within the same subpattern. For example,
+.sp
+  (a(?i)b|c)
+.sp
+matches "ab", "aB", "c", and "C", even though when matching "C" the first
+branch is abandoned before the option setting. This is because the effects of
+option settings happen at compile time. There would be some very weird
+behaviour otherwise.
+.P
+\fBNote:\fP There are other PCRE-specific options that can be set by the
+application when the compiling or matching functions are called. In some cases
+the pattern can contain special leading sequences such as (*CRLF) to override
+what the application has set or what has been defaulted. Details are given in
+the section entitled
+.\" HTML <a href="#newlineseq">
+.\" </a>
+"Newline sequences"
+.\"
+above. There are also the (*UTF8), (*UTF16),(*UTF32), and (*UCP) leading
+sequences that can be used to set UTF and Unicode property modes; they are
+equivalent to setting the PCRE_UTF8, PCRE_UTF16, PCRE_UTF32 and the PCRE_UCP
+options, respectively. The (*UTF) sequence is a generic version that can be
+used with any of the libraries. However, the application can set the
+PCRE_NEVER_UTF option, which locks out the use of the (*UTF) sequences.
+.
+.
+.\" HTML <a name="subpattern"></a>
+.SH SUBPATTERNS
+.rs
+.sp
+Subpatterns are delimited by parentheses (round brackets), which can be nested.
+Turning part of a pattern into a subpattern does two things:
+.sp
+1. It localizes a set of alternatives. For example, the pattern
+.sp
+  cat(aract|erpillar|)
+.sp
+matches "cataract", "caterpillar", or "cat". Without the parentheses, it would
+match "cataract", "erpillar" or an empty string.
+.sp
+2. It sets up the subpattern as a capturing subpattern. This means that, when
+the whole pattern matches, that portion of the subject string that matched the
+subpattern is passed back to the caller via the \fIovector\fP argument of the
+matching function. (This applies only to the traditional matching functions;
+the DFA matching functions do not support capturing.)
+.P
+Opening parentheses are counted from left to right (starting from 1) to obtain
+numbers for the capturing subpatterns. For example, if the string "the red
+king" is matched against the pattern
+.sp
+  the ((red|white) (king|queen))
+.sp
+the captured substrings are "red king", "red", and "king", and are numbered 1,
+2, and 3, respectively.
+.P
+The fact that plain parentheses fulfil two functions is not always helpful.
+There are often times when a grouping subpattern is required without a
+capturing requirement. If an opening parenthesis is followed by a question mark
+and a colon, the subpattern does not do any capturing, and is not counted when
+computing the number of any subsequent capturing subpatterns. For example, if
+the string "the white queen" is matched against the pattern
+.sp
+  the ((?:red|white) (king|queen))
+.sp
+the captured substrings are "white queen" and "queen", and are numbered 1 and
+2. The maximum number of capturing subpatterns is 65535.
+.P
+As a convenient shorthand, if any option settings are required at the start of
+a non-capturing subpattern, the option letters may appear between the "?" and
+the ":". Thus the two patterns
+.sp
+  (?i:saturday|sunday)
+  (?:(?i)saturday|sunday)
+.sp
+match exactly the same set of strings. Because alternative branches are tried
+from left to right, and options are not reset until the end of the subpattern
+is reached, an option setting in one branch does affect subsequent branches, so
+the above patterns match "SUNDAY" as well as "Saturday".
+.
+.
+.\" HTML <a name="dupsubpatternnumber"></a>
+.SH "DUPLICATE SUBPATTERN NUMBERS"
+.rs
+.sp
+Perl 5.10 introduced a feature whereby each alternative in a subpattern uses
+the same numbers for its capturing parentheses. Such a subpattern starts with
+(?| and is itself a non-capturing subpattern. For example, consider this
+pattern:
+.sp
+  (?|(Sat)ur|(Sun))day
+.sp
+Because the two alternatives are inside a (?| group, both sets of capturing
+parentheses are numbered one. Thus, when the pattern matches, you can look
+at captured substring number one, whichever alternative matched. This construct
+is useful when you want to capture part, but not all, of one of a number of
+alternatives. Inside a (?| group, parentheses are numbered as usual, but the
+number is reset at the start of each branch. The numbers of any capturing
+parentheses that follow the subpattern start after the highest number used in
+any branch. The following example is taken from the Perl documentation. The
+numbers underneath show in which buffer the captured content will be stored.
+.sp
+  # before  ---------------branch-reset----------- after
+  / ( a )  (?| x ( y ) z | (p (q) r) | (t) u (v) ) ( z ) /x
+  # 1            2         2  3        2     3     4
+.sp
+A back reference to a numbered subpattern uses the most recent value that is
+set for that number by any subpattern. The following pattern matches "abcabc"
+or "defdef":
+.sp
+  /(?|(abc)|(def))\e1/
+.sp
+In contrast, a subroutine call to a numbered subpattern always refers to the
+first one in the pattern with the given number. The following pattern matches
+"abcabc" or "defabc":
+.sp
+  /(?|(abc)|(def))(?1)/
+.sp
+If a
+.\" HTML <a href="#conditions">
+.\" </a>
+condition test
+.\"
+for a subpattern's having matched refers to a non-unique number, the test is
+true if any of the subpatterns of that number have matched.
+.P
+An alternative approach to using this "branch reset" feature is to use
+duplicate named subpatterns, as described in the next section.
+.
+.
+.SH "NAMED SUBPATTERNS"
+.rs
+.sp
+Identifying capturing parentheses by number is simple, but it can be very hard
+to keep track of the numbers in complicated regular expressions. Furthermore,
+if an expression is modified, the numbers may change. To help with this
+difficulty, PCRE supports the naming of subpatterns. This feature was not
+added to Perl until release 5.10. Python had the feature earlier, and PCRE
+introduced it at release 4.0, using the Python syntax. PCRE now supports both
+the Perl and the Python syntax. Perl allows identically numbered subpatterns to
+have different names, but PCRE does not.
+.P
+In PCRE, a subpattern can be named in one of three ways: (?<name>...) or
+(?'name'...) as in Perl, or (?P<name>...) as in Python. References to capturing
+parentheses from other parts of the pattern, such as
+.\" HTML <a href="#backreferences">
+.\" </a>
+back references,
+.\"
+.\" HTML <a href="#recursion">
+.\" </a>
+recursion,
+.\"
+and
+.\" HTML <a href="#conditions">
+.\" </a>
+conditions,
+.\"
+can be made by name as well as by number.
+.P
+Names consist of up to 32 alphanumeric characters and underscores, but must
+start with a non-digit. Named capturing parentheses are still allocated numbers
+as well as names, exactly as if the names were not present. The PCRE API
+provides function calls for extracting the name-to-number translation table
+from a compiled pattern. There is also a convenience function for extracting a
+captured substring by name.
+.P
+By default, a name must be unique within a pattern, but it is possible to relax
+this constraint by setting the PCRE_DUPNAMES option at compile time. (Duplicate
+names are also always permitted for subpatterns with the same number, set up as
+described in the previous section.) Duplicate names can be useful for patterns
+where only one instance of the named parentheses can match. Suppose you want to
+match the name of a weekday, either as a 3-letter abbreviation or as the full
+name, and in both cases you want to extract the abbreviation. This pattern
+(ignoring the line breaks) does the job:
+.sp
+  (?<DN>Mon|Fri|Sun)(?:day)?|
+  (?<DN>Tue)(?:sday)?|
+  (?<DN>Wed)(?:nesday)?|
+  (?<DN>Thu)(?:rsday)?|
+  (?<DN>Sat)(?:urday)?
+.sp
+There are five capturing substrings, but only one is ever set after a match.
+(An alternative way of solving this problem is to use a "branch reset"
+subpattern, as described in the previous section.)
+.P
+The convenience function for extracting the data by name returns the substring
+for the first (and in this example, the only) subpattern of that name that
+matched. This saves searching to find which numbered subpattern it was.
+.P
+If you make a back reference to a non-unique named subpattern from elsewhere in
+the pattern, the subpatterns to which the name refers are checked in the order
+in which they appear in the overall pattern. The first one that is set is used
+for the reference. For example, this pattern matches both "foofoo" and
+"barbar" but not "foobar" or "barfoo":
+.sp
+  (?:(?<n>foo)|(?<n>bar))\ek<n>
+.sp
+.P
+If you make a subroutine call to a non-unique named subpattern, the one that
+corresponds to the first occurrence of the name is used. In the absence of
+duplicate numbers (see the previous section) this is the one with the lowest
+number.
+.P
+If you use a named reference in a condition
+test (see the
+.\"
+.\" HTML <a href="#conditions">
+.\" </a>
+section about conditions
+.\"
+below), either to check whether a subpattern has matched, or to check for
+recursion, all subpatterns with the same name are tested. If the condition is
+true for any one of them, the overall condition is true. This is the same
+behaviour as testing by number. For further details of the interfaces for
+handling named subpatterns, see the
+.\" HREF
+\fBpcreapi\fP
+.\"
+documentation.
+.P
+\fBWarning:\fP You cannot use different names to distinguish between two
+subpatterns with the same number because PCRE uses only the numbers when
+matching. For this reason, an error is given at compile time if different names
+are given to subpatterns with the same number. However, you can always give the
+same name to subpatterns with the same number, even when PCRE_DUPNAMES is not
+set.
+.
+.
+.SH REPETITION
+.rs
+.sp
+Repetition is specified by quantifiers, which can follow any of the following
+items:
+.sp
+  a literal data character
+  the dot metacharacter
+  the \eC escape sequence
+  the \eX escape sequence
+  the \eR escape sequence
+  an escape such as \ed or \epL that matches a single character
+  a character class
+  a back reference (see next section)
+  a parenthesized subpattern (including assertions)
+  a subroutine call to a subpattern (recursive or otherwise)
+.sp
+The general repetition quantifier specifies a minimum and maximum number of
+permitted matches, by giving the two numbers in curly brackets (braces),
+separated by a comma. The numbers must be less than 65536, and the first must
+be less than or equal to the second. For example:
+.sp
+  z{2,4}
+.sp
+matches "zz", "zzz", or "zzzz". A closing brace on its own is not a special
+character. If the second number is omitted, but the comma is present, there is
+no upper limit; if the second number and the comma are both omitted, the
+quantifier specifies an exact number of required matches. Thus
+.sp
+  [aeiou]{3,}
+.sp
+matches at least 3 successive vowels, but may match many more, while
+.sp
+  \ed{8}
+.sp
+matches exactly 8 digits. An opening curly bracket that appears in a position
+where a quantifier is not allowed, or one that does not match the syntax of a
+quantifier, is taken as a literal character. For example, {,6} is not a
+quantifier, but a literal string of four characters.
+.P
+In UTF modes, quantifiers apply to characters rather than to individual data
+units. Thus, for example, \ex{100}{2} matches two characters, each of
+which is represented by a two-byte sequence in a UTF-8 string. Similarly,
+\eX{3} matches three Unicode extended grapheme clusters, each of which may be
+several data units long (and they may be of different lengths).
+.P
+The quantifier {0} is permitted, causing the expression to behave as if the
+previous item and the quantifier were not present. This may be useful for
+subpatterns that are referenced as
+.\" HTML <a href="#subpatternsassubroutines">
+.\" </a>
+subroutines
+.\"
+from elsewhere in the pattern (but see also the section entitled
+.\" HTML <a href="#subdefine">
+.\" </a>
+"Defining subpatterns for use by reference only"
+.\"
+below). Items other than subpatterns that have a {0} quantifier are omitted
+from the compiled pattern.
+.P
+For convenience, the three most common quantifiers have single-character
+abbreviations:
+.sp
+  *    is equivalent to {0,}
+  +    is equivalent to {1,}
+  ?    is equivalent to {0,1}
+.sp
+It is possible to construct infinite loops by following a subpattern that can
+match no characters with a quantifier that has no upper limit, for example:
+.sp
+  (a?)*
+.sp
+Earlier versions of Perl and PCRE used to give an error at compile time for
+such patterns. However, because there are cases where this can be useful, such
+patterns are now accepted, but if any repetition of the subpattern does in fact
+match no characters, the loop is forcibly broken.
+.P
+By default, the quantifiers are "greedy", that is, they match as much as
+possible (up to the maximum number of permitted times), without causing the
+rest of the pattern to fail. The classic example of where this gives problems
+is in trying to match comments in C programs. These appear between /* and */
+and within the comment, individual * and / characters may appear. An attempt to
+match C comments by applying the pattern
+.sp
+  /\e*.*\e*/
+.sp
+to the string
+.sp
+  /* first comment */  not comment  /* second comment */
+.sp
+fails, because it matches the entire string owing to the greediness of the .*
+item.
+.P
+However, if a quantifier is followed by a question mark, it ceases to be
+greedy, and instead matches the minimum number of times possible, so the
+pattern
+.sp
+  /\e*.*?\e*/
+.sp
+does the right thing with the C comments. The meaning of the various
+quantifiers is not otherwise changed, just the preferred number of matches.
+Do not confuse this use of question mark with its use as a quantifier in its
+own right. Because it has two uses, it can sometimes appear doubled, as in
+.sp
+  \ed??\ed
+.sp
+which matches one digit by preference, but can match two if that is the only
+way the rest of the pattern matches.
+.P
+If the PCRE_UNGREEDY option is set (an option that is not available in Perl),
+the quantifiers are not greedy by default, but individual ones can be made
+greedy by following them with a question mark. In other words, it inverts the
+default behaviour.
+.P
+When a parenthesized subpattern is quantified with a minimum repeat count that
+is greater than 1 or with a limited maximum, more memory is required for the
+compiled pattern, in proportion to the size of the minimum or maximum.
+.P
+If a pattern starts with .* or .{0,} and the PCRE_DOTALL option (equivalent
+to Perl's /s) is set, thus allowing the dot to match newlines, the pattern is
+implicitly anchored, because whatever follows will be tried against every
+character position in the subject string, so there is no point in retrying the
+overall match at any position after the first. PCRE normally treats such a
+pattern as though it were preceded by \eA.
+.P
+In cases where it is known that the subject string contains no newlines, it is
+worth setting PCRE_DOTALL in order to obtain this optimization, or
+alternatively using ^ to indicate anchoring explicitly.
+.P
+However, there are some cases where the optimization cannot be used. When .*
+is inside capturing parentheses that are the subject of a back reference
+elsewhere in the pattern, a match at the start may fail where a later one
+succeeds. Consider, for example:
+.sp
+  (.*)abc\e1
+.sp
+If the subject is "xyz123abc123" the match point is the fourth character. For
+this reason, such a pattern is not implicitly anchored.
+.P
+Another case where implicit anchoring is not applied is when the leading .* is
+inside an atomic group. Once again, a match at the start may fail where a later
+one succeeds. Consider this pattern:
+.sp
+  (?>.*?a)b
+.sp
+It matches "ab" in the subject "aab". The use of the backtracking control verbs
+(*PRUNE) and (*SKIP) also disable this optimization.
+.P
+When a capturing subpattern is repeated, the value captured is the substring
+that matched the final iteration. For example, after
+.sp
+  (tweedle[dume]{3}\es*)+
+.sp
+has matched "tweedledum tweedledee" the value of the captured substring is
+"tweedledee". However, if there are nested capturing subpatterns, the
+corresponding captured values may have been set in previous iterations. For
+example, after
+.sp
+  /(a|(b))+/
+.sp
+matches "aba" the value of the second captured substring is "b".
+.
+.
+.\" HTML <a name="atomicgroup"></a>
+.SH "ATOMIC GROUPING AND POSSESSIVE QUANTIFIERS"
+.rs
+.sp
+With both maximizing ("greedy") and minimizing ("ungreedy" or "lazy")
+repetition, failure of what follows normally causes the repeated item to be
+re-evaluated to see if a different number of repeats allows the rest of the
+pattern to match. Sometimes it is useful to prevent this, either to change the
+nature of the match, or to cause it fail earlier than it otherwise might, when
+the author of the pattern knows there is no point in carrying on.
+.P
+Consider, for example, the pattern \ed+foo when applied to the subject line
+.sp
+  123456bar
+.sp
+After matching all 6 digits and then failing to match "foo", the normal
+action of the matcher is to try again with only 5 digits matching the \ed+
+item, and then with 4, and so on, before ultimately failing. "Atomic grouping"
+(a term taken from Jeffrey Friedl's book) provides the means for specifying
+that once a subpattern has matched, it is not to be re-evaluated in this way.
+.P
+If we use atomic grouping for the previous example, the matcher gives up
+immediately on failing to match "foo" the first time. The notation is a kind of
+special parenthesis, starting with (?> as in this example:
+.sp
+  (?>\ed+)foo
+.sp
+This kind of parenthesis "locks up" the  part of the pattern it contains once
+it has matched, and a failure further into the pattern is prevented from
+backtracking into it. Backtracking past it to previous items, however, works as
+normal.
+.P
+An alternative description is that a subpattern of this type matches the string
+of characters that an identical standalone pattern would match, if anchored at
+the current point in the subject string.
+.P
+Atomic grouping subpatterns are not capturing subpatterns. Simple cases such as
+the above example can be thought of as a maximizing repeat that must swallow
+everything it can. So, while both \ed+ and \ed+? are prepared to adjust the
+number of digits they match in order to make the rest of the pattern match,
+(?>\ed+) can only match an entire sequence of digits.
+.P
+Atomic groups in general can of course contain arbitrarily complicated
+subpatterns, and can be nested. However, when the subpattern for an atomic
+group is just a single repeated item, as in the example above, a simpler
+notation, called a "possessive quantifier" can be used. This consists of an
+additional + character following a quantifier. Using this notation, the
+previous example can be rewritten as
+.sp
+  \ed++foo
+.sp
+Note that a possessive quantifier can be used with an entire group, for
+example:
+.sp
+  (abc|xyz){2,3}+
+.sp
+Possessive quantifiers are always greedy; the setting of the PCRE_UNGREEDY
+option is ignored. They are a convenient notation for the simpler forms of
+atomic group. However, there is no difference in the meaning of a possessive
+quantifier and the equivalent atomic group, though there may be a performance
+difference; possessive quantifiers should be slightly faster.
+.P
+The possessive quantifier syntax is an extension to the Perl 5.8 syntax.
+Jeffrey Friedl originated the idea (and the name) in the first edition of his
+book. Mike McCloskey liked it, so implemented it when he built Sun's Java
+package, and PCRE copied it from there. It ultimately found its way into Perl
+at release 5.10.
+.P
+PCRE has an optimization that automatically "possessifies" certain simple
+pattern constructs. For example, the sequence A+B is treated as A++B because
+there is no point in backtracking into a sequence of A's when B must follow.
+.P
+When a pattern contains an unlimited repeat inside a subpattern that can itself
+be repeated an unlimited number of times, the use of an atomic group is the
+only way to avoid some failing matches taking a very long time indeed. The
+pattern
+.sp
+  (\eD+|<\ed+>)*[!?]
+.sp
+matches an unlimited number of substrings that either consist of non-digits, or
+digits enclosed in <>, followed by either ! or ?. When it matches, it runs
+quickly. However, if it is applied to
+.sp
+  aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+.sp
+it takes a long time before reporting failure. This is because the string can
+be divided between the internal \eD+ repeat and the external * repeat in a
+large number of ways, and all have to be tried. (The example uses [!?] rather
+than a single character at the end, because both PCRE and Perl have an
+optimization that allows for fast failure when a single character is used. They
+remember the last single character that is required for a match, and fail early
+if it is not present in the string.) If the pattern is changed so that it uses
+an atomic group, like this:
+.sp
+  ((?>\eD+)|<\ed+>)*[!?]
+.sp
+sequences of non-digits cannot be broken, and failure happens quickly.
+.
+.
+.\" HTML <a name="backreferences"></a>
+.SH "BACK REFERENCES"
+.rs
+.sp
+Outside a character class, a backslash followed by a digit greater than 0 (and
+possibly further digits) is a back reference to a capturing subpattern earlier
+(that is, to its left) in the pattern, provided there have been that many
+previous capturing left parentheses.
+.P
+However, if the decimal number following the backslash is less than 10, it is
+always taken as a back reference, and causes an error only if there are not
+that many capturing left parentheses in the entire pattern. In other words, the
+parentheses that are referenced need not be to the left of the reference for
+numbers less than 10. A "forward back reference" of this type can make sense
+when a repetition is involved and the subpattern to the right has participated
+in an earlier iteration.
+.P
+It is not possible to have a numerical "forward back reference" to a subpattern
+whose number is 10 or more using this syntax because a sequence such as \e50 is
+interpreted as a character defined in octal. See the subsection entitled
+"Non-printing characters"
+.\" HTML <a href="#digitsafterbackslash">
+.\" </a>
+above
+.\"
+for further details of the handling of digits following a backslash. There is
+no such problem when named parentheses are used. A back reference to any
+subpattern is possible using named parentheses (see below).
+.P
+Another way of avoiding the ambiguity inherent in the use of digits following a
+backslash is to use the \eg escape sequence. This escape must be followed by an
+unsigned number or a negative number, optionally enclosed in braces. These
+examples are all identical:
+.sp
+  (ring), \e1
+  (ring), \eg1
+  (ring), \eg{1}
+.sp
+An unsigned number specifies an absolute reference without the ambiguity that
+is present in the older syntax. It is also useful when literal digits follow
+the reference. A negative number is a relative reference. Consider this
+example:
+.sp
+  (abc(def)ghi)\eg{-1}
+.sp
+The sequence \eg{-1} is a reference to the most recently started capturing
+subpattern before \eg, that is, is it equivalent to \e2 in this example.
+Similarly, \eg{-2} would be equivalent to \e1. The use of relative references
+can be helpful in long patterns, and also in patterns that are created by
+joining together fragments that contain references within themselves.
+.P
+A back reference matches whatever actually matched the capturing subpattern in
+the current subject string, rather than anything matching the subpattern
+itself (see
+.\" HTML <a href="#subpatternsassubroutines">
+.\" </a>
+"Subpatterns as subroutines"
+.\"
+below for a way of doing that). So the pattern
+.sp
+  (sens|respons)e and \e1ibility
+.sp
+matches "sense and sensibility" and "response and responsibility", but not
+"sense and responsibility". If caseful matching is in force at the time of the
+back reference, the case of letters is relevant. For example,
+.sp
+  ((?i)rah)\es+\e1
+.sp
+matches "rah rah" and "RAH RAH", but not "RAH rah", even though the original
+capturing subpattern is matched caselessly.
+.P
+There are several different ways of writing back references to named
+subpatterns. The .NET syntax \ek{name} and the Perl syntax \ek<name> or
+\ek'name' are supported, as is the Python syntax (?P=name). Perl 5.10's unified
+back reference syntax, in which \eg can be used for both numeric and named
+references, is also supported. We could rewrite the above example in any of
+the following ways:
+.sp
+  (?<p1>(?i)rah)\es+\ek<p1>
+  (?'p1'(?i)rah)\es+\ek{p1}
+  (?P<p1>(?i)rah)\es+(?P=p1)
+  (?<p1>(?i)rah)\es+\eg{p1}
+.sp
+A subpattern that is referenced by name may appear in the pattern before or
+after the reference.
+.P
+There may be more than one back reference to the same subpattern. If a
+subpattern has not actually been used in a particular match, any back
+references to it always fail by default. For example, the pattern
+.sp
+  (a|(bc))\e2
+.sp
+always fails if it starts to match "a" rather than "bc". However, if the
+PCRE_JAVASCRIPT_COMPAT option is set at compile time, a back reference to an
+unset value matches an empty string.
+.P
+Because there may be many capturing parentheses in a pattern, all digits
+following a backslash are taken as part of a potential back reference number.
+If the pattern continues with a digit character, some delimiter must be used to
+terminate the back reference. If the PCRE_EXTENDED option is set, this can be
+white space. Otherwise, the \eg{ syntax or an empty comment (see
+.\" HTML <a href="#comments">
+.\" </a>
+"Comments"
+.\"
+below) can be used.
+.
+.SS "Recursive back references"
+.rs
+.sp
+A back reference that occurs inside the parentheses to which it refers fails
+when the subpattern is first used, so, for example, (a\e1) never matches.
+However, such references can be useful inside repeated subpatterns. For
+example, the pattern
+.sp
+  (a|b\e1)+
+.sp
+matches any number of "a"s and also "aba", "ababbaa" etc. At each iteration of
+the subpattern, the back reference matches the character string corresponding
+to the previous iteration. In order for this to work, the pattern must be such
+that the first iteration does not need to match the back reference. This can be
+done using alternation, as in the example above, or by a quantifier with a
+minimum of zero.
+.P
+Back references of this type cause the group that they reference to be treated
+as an
+.\" HTML <a href="#atomicgroup">
+.\" </a>
+atomic group.
+.\"
+Once the whole group has been matched, a subsequent matching failure cannot
+cause backtracking into the middle of the group.
+.
+.
+.\" HTML <a name="bigassertions"></a>
+.SH ASSERTIONS
+.rs
+.sp
+An assertion is a test on the characters following or preceding the current
+matching point that does not actually consume any characters. The simple
+assertions coded as \eb, \eB, \eA, \eG, \eZ, \ez, ^ and $ are described
+.\" HTML <a href="#smallassertions">
+.\" </a>
+above.
+.\"
+.P
+More complicated assertions are coded as subpatterns. There are two kinds:
+those that look ahead of the current position in the subject string, and those
+that look behind it. An assertion subpattern is matched in the normal way,
+except that it does not cause the current matching position to be changed.
+.P
+Assertion subpatterns are not capturing subpatterns. If such an assertion
+contains capturing subpatterns within it, these are counted for the purposes of
+numbering the capturing subpatterns in the whole pattern. However, substring
+capturing is carried out only for positive assertions. (Perl sometimes, but not
+always, does do capturing in negative assertions.)
+.P
+For compatibility with Perl, assertion subpatterns may be repeated; though
+it makes no sense to assert the same thing several times, the side effect of
+capturing parentheses may occasionally be useful. In practice, there only three
+cases:
+.sp
+(1) If the quantifier is {0}, the assertion is never obeyed during matching.
+However, it may contain internal capturing parenthesized groups that are called
+from elsewhere via the
+.\" HTML <a href="#subpatternsassubroutines">
+.\" </a>
+subroutine mechanism.
+.\"
+.sp
+(2) If quantifier is {0,n} where n is greater than zero, it is treated as if it
+were {0,1}. At run time, the rest of the pattern match is tried with and
+without the assertion, the order depending on the greediness of the quantifier.
+.sp
+(3) If the minimum repetition is greater than zero, the quantifier is ignored.
+The assertion is obeyed just once when encountered during matching.
+.
+.
+.SS "Lookahead assertions"
+.rs
+.sp
+Lookahead assertions start with (?= for positive assertions and (?! for
+negative assertions. For example,
+.sp
+  \ew+(?=;)
+.sp
+matches a word followed by a semicolon, but does not include the semicolon in
+the match, and
+.sp
+  foo(?!bar)
+.sp
+matches any occurrence of "foo" that is not followed by "bar". Note that the
+apparently similar pattern
+.sp
+  (?!foo)bar
+.sp
+does not find an occurrence of "bar" that is preceded by something other than
+"foo"; it finds any occurrence of "bar" whatsoever, because the assertion
+(?!foo) is always true when the next three characters are "bar". A
+lookbehind assertion is needed to achieve the other effect.
+.P
+If you want to force a matching failure at some point in a pattern, the most
+convenient way to do it is with (?!) because an empty string always matches, so
+an assertion that requires there not to be an empty string must always fail.
+The backtracking control verb (*FAIL) or (*F) is a synonym for (?!).
+.
+.
+.\" HTML <a name="lookbehind"></a>
+.SS "Lookbehind assertions"
+.rs
+.sp
+Lookbehind assertions start with (?<= for positive assertions and (?<! for
+negative assertions. For example,
+.sp
+  (?<!foo)bar
+.sp
+does find an occurrence of "bar" that is not preceded by "foo". The contents of
+a lookbehind assertion are restricted such that all the strings it matches must
+have a fixed length. However, if there are several top-level alternatives, they
+do not all have to have the same fixed length. Thus
+.sp
+  (?<=bullock|donkey)
+.sp
+is permitted, but
+.sp
+  (?<!dogs?|cats?)
+.sp
+causes an error at compile time. Branches that match different length strings
+are permitted only at the top level of a lookbehind assertion. This is an
+extension compared with Perl, which requires all branches to match the same
+length of string. An assertion such as
+.sp
+  (?<=ab(c|de))
+.sp
+is not permitted, because its single top-level branch can match two different
+lengths, but it is acceptable to PCRE if rewritten to use two top-level
+branches:
+.sp
+  (?<=abc|abde)
+.sp
+In some cases, the escape sequence \eK
+.\" HTML <a href="#resetmatchstart">
+.\" </a>
+(see above)
+.\"
+can be used instead of a lookbehind assertion to get round the fixed-length
+restriction.
+.P
+The implementation of lookbehind assertions is, for each alternative, to
+temporarily move the current position back by the fixed length and then try to
+match. If there are insufficient characters before the current position, the
+assertion fails.
+.P
+In a UTF mode, PCRE does not allow the \eC escape (which matches a single data
+unit even in a UTF mode) to appear in lookbehind assertions, because it makes
+it impossible to calculate the length of the lookbehind. The \eX and \eR
+escapes, which can match different numbers of data units, are also not
+permitted.
+.P
+.\" HTML <a href="#subpatternsassubroutines">
+.\" </a>
+"Subroutine"
+.\"
+calls (see below) such as (?2) or (?&X) are permitted in lookbehinds, as long
+as the subpattern matches a fixed-length string.
+.\" HTML <a href="#recursion">
+.\" </a>
+Recursion,
+.\"
+however, is not supported.
+.P
+Possessive quantifiers can be used in conjunction with lookbehind assertions to
+specify efficient matching of fixed-length strings at the end of subject
+strings. Consider a simple pattern such as
+.sp
+  abcd$
+.sp
+when applied to a long string that does not match. Because matching proceeds
+from left to right, PCRE will look for each "a" in the subject and then see if
+what follows matches the rest of the pattern. If the pattern is specified as
+.sp
+  ^.*abcd$
+.sp
+the initial .* matches the entire string at first, but when this fails (because
+there is no following "a"), it backtracks to match all but the last character,
+then all but the last two characters, and so on. Once again the search for "a"
+covers the entire string, from right to left, so we are no better off. However,
+if the pattern is written as
+.sp
+  ^.*+(?<=abcd)
+.sp
+there can be no backtracking for the .*+ item; it can match only the entire
+string. The subsequent lookbehind assertion does a single test on the last four
+characters. If it fails, the match fails immediately. For long strings, this
+approach makes a significant difference to the processing time.
+.
+.
+.SS "Using multiple assertions"
+.rs
+.sp
+Several assertions (of any sort) may occur in succession. For example,
+.sp
+  (?<=\ed{3})(?<!999)foo
+.sp
+matches "foo" preceded by three digits that are not "999". Notice that each of
+the assertions is applied independently at the same point in the subject
+string. First there is a check that the previous three characters are all
+digits, and then there is a check that the same three characters are not "999".
+This pattern does \fInot\fP match "foo" preceded by six characters, the first
+of which are digits and the last three of which are not "999". For example, it
+doesn't match "123abcfoo". A pattern to do that is
+.sp
+  (?<=\ed{3}...)(?<!999)foo
+.sp
+This time the first assertion looks at the preceding six characters, checking
+that the first three are digits, and then the second assertion checks that the
+preceding three characters are not "999".
+.P
+Assertions can be nested in any combination. For example,
+.sp
+  (?<=(?<!foo)bar)baz
+.sp
+matches an occurrence of "baz" that is preceded by "bar" which in turn is not
+preceded by "foo", while
+.sp
+  (?<=\ed{3}(?!999)...)foo
+.sp
+is another pattern that matches "foo" preceded by three digits and any three
+characters that are not "999".
+.
+.
+.\" HTML <a name="conditions"></a>
+.SH "CONDITIONAL SUBPATTERNS"
+.rs
+.sp
+It is possible to cause the matching process to obey a subpattern
+conditionally or to choose between two alternative subpatterns, depending on
+the result of an assertion, or whether a specific capturing subpattern has
+already been matched. The two possible forms of conditional subpattern are:
+.sp
+  (?(condition)yes-pattern)
+  (?(condition)yes-pattern|no-pattern)
+.sp
+If the condition is satisfied, the yes-pattern is used; otherwise the
+no-pattern (if present) is used. If there are more than two alternatives in the
+subpattern, a compile-time error occurs. Each of the two alternatives may
+itself contain nested subpatterns of any form, including conditional
+subpatterns; the restriction to two alternatives applies only at the level of
+the condition. This pattern fragment is an example where the alternatives are
+complex:
+.sp
+  (?(1) (A|B|C) | (D | (?(2)E|F) | E) )
+.sp
+.P
+There are four kinds of condition: references to subpatterns, references to
+recursion, a pseudo-condition called DEFINE, and assertions.
+.
+.SS "Checking for a used subpattern by number"
+.rs
+.sp
+If the text between the parentheses consists of a sequence of digits, the
+condition is true if a capturing subpattern of that number has previously
+matched. If there is more than one capturing subpattern with the same number
+(see the earlier
+.\"
+.\" HTML <a href="#recursion">
+.\" </a>
+section about duplicate subpattern numbers),
+.\"
+the condition is true if any of them have matched. An alternative notation is
+to precede the digits with a plus or minus sign. In this case, the subpattern
+number is relative rather than absolute. The most recently opened parentheses
+can be referenced by (?(-1), the next most recent by (?(-2), and so on. Inside
+loops it can also make sense to refer to subsequent groups. The next
+parentheses to be opened can be referenced as (?(+1), and so on. (The value
+zero in any of these forms is not used; it provokes a compile-time error.)
+.P
+Consider the following pattern, which contains non-significant white space to
+make it more readable (assume the PCRE_EXTENDED option) and to divide it into
+three parts for ease of discussion:
+.sp
+  ( \e( )?    [^()]+    (?(1) \e) )
+.sp
+The first part matches an optional opening parenthesis, and if that
+character is present, sets it as the first captured substring. The second part
+matches one or more characters that are not parentheses. The third part is a
+conditional subpattern that tests whether or not the first set of parentheses
+matched. If they did, that is, if subject started with an opening parenthesis,
+the condition is true, and so the yes-pattern is executed and a closing
+parenthesis is required. Otherwise, since no-pattern is not present, the
+subpattern matches nothing. In other words, this pattern matches a sequence of
+non-parentheses, optionally enclosed in parentheses.
+.P
+If you were embedding this pattern in a larger one, you could use a relative
+reference:
+.sp
+  ...other stuff... ( \e( )?    [^()]+    (?(-1) \e) ) ...
+.sp
+This makes the fragment independent of the parentheses in the larger pattern.
+.
+.SS "Checking for a used subpattern by name"
+.rs
+.sp
+Perl uses the syntax (?(<name>)...) or (?('name')...) to test for a used
+subpattern by name. For compatibility with earlier versions of PCRE, which had
+this facility before Perl, the syntax (?(name)...) is also recognized.
+.P
+Rewriting the above example to use a named subpattern gives this:
+.sp
+  (?<OPEN> \e( )?    [^()]+    (?(<OPEN>) \e) )
+.sp
+If the name used in a condition of this kind is a duplicate, the test is
+applied to all subpatterns of the same name, and is true if any one of them has
+matched.
+.
+.SS "Checking for pattern recursion"
+.rs
+.sp
+If the condition is the string (R), and there is no subpattern with the name R,
+the condition is true if a recursive call to the whole pattern or any
+subpattern has been made. If digits or a name preceded by ampersand follow the
+letter R, for example:
+.sp
+  (?(R3)...) or (?(R&name)...)
+.sp
+the condition is true if the most recent recursion is into a subpattern whose
+number or name is given. This condition does not check the entire recursion
+stack. If the name used in a condition of this kind is a duplicate, the test is
+applied to all subpatterns of the same name, and is true if any one of them is
+the most recent recursion.
+.P
+At "top level", all these recursion test conditions are false.
+.\" HTML <a href="#recursion">
+.\" </a>
+The syntax for recursive patterns
+.\"
+is described below.
+.
+.\" HTML <a name="subdefine"></a>
+.SS "Defining subpatterns for use by reference only"
+.rs
+.sp
+If the condition is the string (DEFINE), and there is no subpattern with the
+name DEFINE, the condition is always false. In this case, there may be only one
+alternative in the subpattern. It is always skipped if control reaches this
+point in the pattern; the idea of DEFINE is that it can be used to define
+subroutines that can be referenced from elsewhere. (The use of
+.\" HTML <a href="#subpatternsassubroutines">
+.\" </a>
+subroutines
+.\"
+is described below.) For example, a pattern to match an IPv4 address such as
+"192.168.23.245" could be written like this (ignore white space and line
+breaks):
+.sp
+  (?(DEFINE) (?<byte> 2[0-4]\ed | 25[0-5] | 1\ed\ed | [1-9]?\ed) )
+  \eb (?&byte) (\e.(?&byte)){3} \eb
+.sp
+The first part of the pattern is a DEFINE group inside which a another group
+named "byte" is defined. This matches an individual component of an IPv4
+address (a number less than 256). When matching takes place, this part of the
+pattern is skipped because DEFINE acts like a false condition. The rest of the
+pattern uses references to the named group to match the four dot-separated
+components of an IPv4 address, insisting on a word boundary at each end.
+.
+.SS "Assertion conditions"
+.rs
+.sp
+If the condition is not in any of the above formats, it must be an assertion.
+This may be a positive or negative lookahead or lookbehind assertion. Consider
+this pattern, again containing non-significant white space, and with the two
+alternatives on the second line:
+.sp
+  (?(?=[^a-z]*[a-z])
+  \ed{2}-[a-z]{3}-\ed{2}  |  \ed{2}-\ed{2}-\ed{2} )
+.sp
+The condition is a positive lookahead assertion that matches an optional
+sequence of non-letters followed by a letter. In other words, it tests for the
+presence of at least one letter in the subject. If a letter is found, the
+subject is matched against the first alternative; otherwise it is matched
+against the second. This pattern matches strings in one of the two forms
+dd-aaa-dd or dd-dd-dd, where aaa are letters and dd are digits.
+.
+.
+.\" HTML <a name="comments"></a>
+.SH COMMENTS
+.rs
+.sp
+There are two ways of including comments in patterns that are processed by
+PCRE. In both cases, the start of the comment must not be in a character class,
+nor in the middle of any other sequence of related characters such as (?: or a
+subpattern name or number. The characters that make up a comment play no part
+in the pattern matching.
+.P
+The sequence (?# marks the start of a comment that continues up to the next
+closing parenthesis. Nested parentheses are not permitted. If the PCRE_EXTENDED
+option is set, an unescaped # character also introduces a comment, which in
+this case continues to immediately after the next newline character or
+character sequence in the pattern. Which characters are interpreted as newlines
+is controlled by the options passed to a compiling function or by a special
+sequence at the start of the pattern, as described in the section entitled
+.\" HTML <a href="#newlines">
+.\" </a>
+"Newline conventions"
+.\"
+above. Note that the end of this type of comment is a literal newline sequence
+in the pattern; escape sequences that happen to represent a newline do not
+count. For example, consider this pattern when PCRE_EXTENDED is set, and the
+default newline convention is in force:
+.sp
+  abc #comment \en still comment
+.sp
+On encountering the # character, \fBpcre_compile()\fP skips along, looking for
+a newline in the pattern. The sequence \en is still literal at this stage, so
+it does not terminate the comment. Only an actual character with the code value
+0x0a (the default newline) does so.
+.
+.
+.\" HTML <a name="recursion"></a>
+.SH "RECURSIVE PATTERNS"
+.rs
+.sp
+Consider the problem of matching a string in parentheses, allowing for
+unlimited nested parentheses. Without the use of recursion, the best that can
+be done is to use a pattern that matches up to some fixed depth of nesting. It
+is not possible to handle an arbitrary nesting depth.
+.P
+For some time, Perl has provided a facility that allows regular expressions to
+recurse (amongst other things). It does this by interpolating Perl code in the
+expression at run time, and the code can refer to the expression itself. A Perl
+pattern using code interpolation to solve the parentheses problem can be
+created like this:
+.sp
+  $re = qr{\e( (?: (?>[^()]+) | (?p{$re}) )* \e)}x;
+.sp
+The (?p{...}) item interpolates Perl code at run time, and in this case refers
+recursively to the pattern in which it appears.
+.P
+Obviously, PCRE cannot support the interpolation of Perl code. Instead, it
+supports special syntax for recursion of the entire pattern, and also for
+individual subpattern recursion. After its introduction in PCRE and Python,
+this kind of recursion was subsequently introduced into Perl at release 5.10.
+.P
+A special item that consists of (? followed by a number greater than zero and a
+closing parenthesis is a recursive subroutine call of the subpattern of the
+given number, provided that it occurs inside that subpattern. (If not, it is a
+.\" HTML <a href="#subpatternsassubroutines">
+.\" </a>
+non-recursive subroutine
+.\"
+call, which is described in the next section.) The special item (?R) or (?0) is
+a recursive call of the entire regular expression.
+.P
+This PCRE pattern solves the nested parentheses problem (assume the
+PCRE_EXTENDED option is set so that white space is ignored):
+.sp
+  \e( ( [^()]++ | (?R) )* \e)
+.sp
+First it matches an opening parenthesis. Then it matches any number of
+substrings which can either be a sequence of non-parentheses, or a recursive
+match of the pattern itself (that is, a correctly parenthesized substring).
+Finally there is a closing parenthesis. Note the use of a possessive quantifier
+to avoid backtracking into sequences of non-parentheses.
+.P
+If this were part of a larger pattern, you would not want to recurse the entire
+pattern, so instead you could use this:
+.sp
+  ( \e( ( [^()]++ | (?1) )* \e) )
+.sp
+We have put the pattern into parentheses, and caused the recursion to refer to
+them instead of the whole pattern.
+.P
+In a larger pattern, keeping track of parenthesis numbers can be tricky. This
+is made easier by the use of relative references. Instead of (?1) in the
+pattern above you can write (?-2) to refer to the second most recently opened
+parentheses preceding the recursion. In other words, a negative number counts
+capturing parentheses leftwards from the point at which it is encountered.
+.P
+It is also possible to refer to subsequently opened parentheses, by writing
+references such as (?+2). However, these cannot be recursive because the
+reference is not inside the parentheses that are referenced. They are always
+.\" HTML <a href="#subpatternsassubroutines">
+.\" </a>
+non-recursive subroutine
+.\"
+calls, as described in the next section.
+.P
+An alternative approach is to use named parentheses instead. The Perl syntax
+for this is (?&name); PCRE's earlier syntax (?P>name) is also supported. We
+could rewrite the above example as follows:
+.sp
+  (?<pn> \e( ( [^()]++ | (?&pn) )* \e) )
+.sp
+If there is more than one subpattern with the same name, the earliest one is
+used.
+.P
+This particular example pattern that we have been looking at contains nested
+unlimited repeats, and so the use of a possessive quantifier for matching
+strings of non-parentheses is important when applying the pattern to strings
+that do not match. For example, when this pattern is applied to
+.sp
+  (aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa()
+.sp
+it yields "no match" quickly. However, if a possessive quantifier is not used,
+the match runs for a very long time indeed because there are so many different
+ways the + and * repeats can carve up the subject, and all have to be tested
+before failure can be reported.
+.P
+At the end of a match, the values of capturing parentheses are those from
+the outermost level. If you want to obtain intermediate values, a callout
+function can be used (see below and the
+.\" HREF
+\fBpcrecallout\fP
+.\"
+documentation). If the pattern above is matched against
+.sp
+  (ab(cd)ef)
+.sp
+the value for the inner capturing parentheses (numbered 2) is "ef", which is
+the last value taken on at the top level. If a capturing subpattern is not
+matched at the top level, its final captured value is unset, even if it was
+(temporarily) set at a deeper level during the matching process.
+.P
+If there are more than 15 capturing parentheses in a pattern, PCRE has to
+obtain extra memory to store data during a recursion, which it does by using
+\fBpcre_malloc\fP, freeing it via \fBpcre_free\fP afterwards. If no memory can
+be obtained, the match fails with the PCRE_ERROR_NOMEMORY error.
+.P
+Do not confuse the (?R) item with the condition (R), which tests for recursion.
+Consider this pattern, which matches text in angle brackets, allowing for
+arbitrary nesting. Only digits are allowed in nested brackets (that is, when
+recursing), whereas any characters are permitted at the outer level.
+.sp
+  < (?: (?(R) \ed++  | [^<>]*+) | (?R)) * >
+.sp
+In this pattern, (?(R) is the start of a conditional subpattern, with two
+different alternatives for the recursive and non-recursive cases. The (?R) item
+is the actual recursive call.
+.
+.
+.\" HTML <a name="recursiondifference"></a>
+.SS "Differences in recursion processing between PCRE and Perl"
+.rs
+.sp
+Recursion processing in PCRE differs from Perl in two important ways. In PCRE
+(like Python, but unlike Perl), a recursive subpattern call is always treated
+as an atomic group. That is, once it has matched some of the subject string, it
+is never re-entered, even if it contains untried alternatives and there is a
+subsequent matching failure. This can be illustrated by the following pattern,
+which purports to match a palindromic string that contains an odd number of
+characters (for example, "a", "aba", "abcba", "abcdcba"):
+.sp
+  ^(.|(.)(?1)\e2)$
+.sp
+The idea is that it either matches a single character, or two identical
+characters surrounding a sub-palindrome. In Perl, this pattern works; in PCRE
+it does not if the pattern is longer than three characters. Consider the
+subject string "abcba":
+.P
+At the top level, the first character is matched, but as it is not at the end
+of the string, the first alternative fails; the second alternative is taken
+and the recursion kicks in. The recursive call to subpattern 1 successfully
+matches the next character ("b"). (Note that the beginning and end of line
+tests are not part of the recursion).
+.P
+Back at the top level, the next character ("c") is compared with what
+subpattern 2 matched, which was "a". This fails. Because the recursion is
+treated as an atomic group, there are now no backtracking points, and so the
+entire match fails. (Perl is able, at this point, to re-enter the recursion and
+try the second alternative.) However, if the pattern is written with the
+alternatives in the other order, things are different:
+.sp
+  ^((.)(?1)\e2|.)$
+.sp
+This time, the recursing alternative is tried first, and continues to recurse
+until it runs out of characters, at which point the recursion fails. But this
+time we do have another alternative to try at the higher level. That is the big
+difference: in the previous case the remaining alternative is at a deeper
+recursion level, which PCRE cannot use.
+.P
+To change the pattern so that it matches all palindromic strings, not just
+those with an odd number of characters, it is tempting to change the pattern to
+this:
+.sp
+  ^((.)(?1)\e2|.?)$
+.sp
+Again, this works in Perl, but not in PCRE, and for the same reason. When a
+deeper recursion has matched a single character, it cannot be entered again in
+order to match an empty string. The solution is to separate the two cases, and
+write out the odd and even cases as alternatives at the higher level:
+.sp
+  ^(?:((.)(?1)\e2|)|((.)(?3)\e4|.))
+.sp
+If you want to match typical palindromic phrases, the pattern has to ignore all
+non-word characters, which can be done like this:
+.sp
+  ^\eW*+(?:((.)\eW*+(?1)\eW*+\e2|)|((.)\eW*+(?3)\eW*+\e4|\eW*+.\eW*+))\eW*+$
+.sp
+If run with the PCRE_CASELESS option, this pattern matches phrases such as "A
+man, a plan, a canal: Panama!" and it works well in both PCRE and Perl. Note
+the use of the possessive quantifier *+ to avoid backtracking into sequences of
+non-word characters. Without this, PCRE takes a great deal longer (ten times or
+more) to match typical phrases, and Perl takes so long that you think it has
+gone into a loop.
+.P
+\fBWARNING\fP: The palindrome-matching patterns above work only if the subject
+string does not start with a palindrome that is shorter than the entire string.
+For example, although "abcba" is correctly matched, if the subject is "ababa",
+PCRE finds the palindrome "aba" at the start, then fails at top level because
+the end of the string does not follow. Once again, it cannot jump back into the
+recursion to try other alternatives, so the entire match fails.
+.P
+The second way in which PCRE and Perl differ in their recursion processing is
+in the handling of captured values. In Perl, when a subpattern is called
+recursively or as a subpattern (see the next section), it has no access to any
+values that were captured outside the recursion, whereas in PCRE these values
+can be referenced. Consider this pattern:
+.sp
+  ^(.)(\e1|a(?2))
+.sp
+In PCRE, this pattern matches "bab". The first capturing parentheses match "b",
+then in the second group, when the back reference \e1 fails to match "b", the
+second alternative matches "a" and then recurses. In the recursion, \e1 does
+now match "b" and so the whole match succeeds. In Perl, the pattern fails to
+match because inside the recursive call \e1 cannot access the externally set
+value.
+.
+.
+.\" HTML <a name="subpatternsassubroutines"></a>
+.SH "SUBPATTERNS AS SUBROUTINES"
+.rs
+.sp
+If the syntax for a recursive subpattern call (either by number or by
+name) is used outside the parentheses to which it refers, it operates like a
+subroutine in a programming language. The called subpattern may be defined
+before or after the reference. A numbered reference can be absolute or
+relative, as in these examples:
+.sp
+  (...(absolute)...)...(?2)...
+  (...(relative)...)...(?-1)...
+  (...(?+1)...(relative)...
+.sp
+An earlier example pointed out that the pattern
+.sp
+  (sens|respons)e and \e1ibility
+.sp
+matches "sense and sensibility" and "response and responsibility", but not
+"sense and responsibility". If instead the pattern
+.sp
+  (sens|respons)e and (?1)ibility
+.sp
+is used, it does match "sense and responsibility" as well as the other two
+strings. Another example is given in the discussion of DEFINE above.
+.P
+All subroutine calls, whether recursive or not, are always treated as atomic
+groups. That is, once a subroutine has matched some of the subject string, it
+is never re-entered, even if it contains untried alternatives and there is a
+subsequent matching failure. Any capturing parentheses that are set during the
+subroutine call revert to their previous values afterwards.
+.P
+Processing options such as case-independence are fixed when a subpattern is
+defined, so if it is used as a subroutine, such options cannot be changed for
+different calls. For example, consider this pattern:
+.sp
+  (abc)(?i:(?-1))
+.sp
+It matches "abcabc". It does not match "abcABC" because the change of
+processing option does not affect the called subpattern.
+.
+.
+.\" HTML <a name="onigurumasubroutines"></a>
+.SH "ONIGURUMA SUBROUTINE SYNTAX"
+.rs
+.sp
+For compatibility with Oniguruma, the non-Perl syntax \eg followed by a name or
+a number enclosed either in angle brackets or single quotes, is an alternative
+syntax for referencing a subpattern as a subroutine, possibly recursively. Here
+are two of the examples used above, rewritten using this syntax:
+.sp
+  (?<pn> \e( ( (?>[^()]+) | \eg<pn> )* \e) )
+  (sens|respons)e and \eg'1'ibility
+.sp
+PCRE supports an extension to Oniguruma: if a number is preceded by a
+plus or a minus sign it is taken as a relative reference. For example:
+.sp
+  (abc)(?i:\eg<-1>)
+.sp
+Note that \eg{...} (Perl syntax) and \eg<...> (Oniguruma syntax) are \fInot\fP
+synonymous. The former is a back reference; the latter is a subroutine call.
+.
+.
+.SH CALLOUTS
+.rs
+.sp
+Perl has a feature whereby using the sequence (?{...}) causes arbitrary Perl
+code to be obeyed in the middle of matching a regular expression. This makes it
+possible, amongst other things, to extract different substrings that match the
+same pair of parentheses when there is a repetition.
+.P
+PCRE provides a similar feature, but of course it cannot obey arbitrary Perl
+code. The feature is called "callout". The caller of PCRE provides an external
+function by putting its entry point in the global variable \fIpcre_callout\fP
+(8-bit library) or \fIpcre[16|32]_callout\fP (16-bit or 32-bit library).
+By default, this variable contains NULL, which disables all calling out.
+.P
+Within a regular expression, (?C) indicates the points at which the external
+function is to be called. If you want to identify different callout points, you
+can put a number less than 256 after the letter C. The default value is zero.
+For example, this pattern has two callout points:
+.sp
+  (?C1)abc(?C2)def
+.sp
+If the PCRE_AUTO_CALLOUT flag is passed to a compiling function, callouts are
+automatically installed before each item in the pattern. They are all numbered
+255. If there is a conditional group in the pattern whose condition is an
+assertion, an additional callout is inserted just before the condition. An
+explicit callout may also be set at this position, as in this example:
+.sp
+  (?(?C9)(?=a)abc|def)
+.sp
+Note that this applies only to assertion conditions, not to other types of
+condition.
+.P
+During matching, when PCRE reaches a callout point, the external function is
+called. It is provided with the number of the callout, the position in the
+pattern, and, optionally, one item of data originally supplied by the caller of
+the matching function. The callout function may cause matching to proceed, to
+backtrack, or to fail altogether.
+.P
+By default, PCRE implements a number of optimizations at compile time and
+matching time, and one side-effect is that sometimes callouts are skipped. If
+you need all possible callouts to happen, you need to set options that disable
+the relevant optimizations. More details, and a complete description of the
+interface to the callout function, are given in the
+.\" HREF
+\fBpcrecallout\fP
+.\"
+documentation.
+.
+.
+.\" HTML <a name="backtrackcontrol"></a>
+.SH "BACKTRACKING CONTROL"
+.rs
+.sp
+Perl 5.10 introduced a number of "Special Backtracking Control Verbs", which
+are still described in the Perl documentation as "experimental and subject to
+change or removal in a future version of Perl". It goes on to say: "Their usage
+in production code should be noted to avoid problems during upgrades." The same
+remarks apply to the PCRE features described in this section.
+.P
+The new verbs make use of what was previously invalid syntax: an opening
+parenthesis followed by an asterisk. They are generally of the form
+(*VERB) or (*VERB:NAME). Some may take either form, possibly behaving
+differently depending on whether or not a name is present. A name is any
+sequence of characters that does not include a closing parenthesis. The maximum
+length of name is 255 in the 8-bit library and 65535 in the 16-bit and 32-bit
+libraries. If the name is empty, that is, if the closing parenthesis
+immediately follows the colon, the effect is as if the colon were not there.
+Any number of these verbs may occur in a pattern.
+.P
+Since these verbs are specifically related to backtracking, most of them can be
+used only when the pattern is to be matched using one of the traditional
+matching functions, because these use a backtracking algorithm. With the
+exception of (*FAIL), which behaves like a failing negative assertion, the
+backtracking control verbs cause an error if encountered by a DFA matching
+function.
+.P
+The behaviour of these verbs in
+.\" HTML <a href="#btrepeat">
+.\" </a>
+repeated groups,
+.\"
+.\" HTML <a href="#btassert">
+.\" </a>
+assertions,
+.\"
+and in
+.\" HTML <a href="#btsub">
+.\" </a>
+subpatterns called as subroutines
+.\"
+(whether or not recursively) is documented below.
+.
+.
+.\" HTML <a name="nooptimize"></a>
+.SS "Optimizations that affect backtracking verbs"
+.rs
+.sp
+PCRE contains some optimizations that are used to speed up matching by running
+some checks at the start of each match attempt. For example, it may know the
+minimum length of matching subject, or that a particular character must be
+present. When one of these optimizations bypasses the running of a match, any
+included backtracking verbs will not, of course, be processed. You can suppress
+the start-of-match optimizations by setting the PCRE_NO_START_OPTIMIZE option
+when calling \fBpcre_compile()\fP or \fBpcre_exec()\fP, or by starting the
+pattern with (*NO_START_OPT). There is more discussion of this option in the
+section entitled
+.\" HTML <a href="pcreapi.html#execoptions">
+.\" </a>
+"Option bits for \fBpcre_exec()\fP"
+.\"
+in the
+.\" HREF
+\fBpcreapi\fP
+.\"
+documentation.
+.P
+Experiments with Perl suggest that it too has similar optimizations, sometimes
+leading to anomalous results.
+.
+.
+.SS "Verbs that act immediately"
+.rs
+.sp
+The following verbs act as soon as they are encountered. They may not be
+followed by a name.
+.sp
+   (*ACCEPT)
+.sp
+This verb causes the match to end successfully, skipping the remainder of the
+pattern. However, when it is inside a subpattern that is called as a
+subroutine, only that subpattern is ended successfully. Matching then continues
+at the outer level. If (*ACCEPT) in triggered in a positive assertion, the
+assertion succeeds; in a negative assertion, the assertion fails.
+.P
+If (*ACCEPT) is inside capturing parentheses, the data so far is captured. For
+example:
+.sp
+  A((?:A|B(*ACCEPT)|C)D)
+.sp
+This matches "AB", "AAD", or "ACD"; when it matches "AB", "B" is captured by
+the outer parentheses.
+.sp
+  (*FAIL) or (*F)
+.sp
+This verb causes a matching failure, forcing backtracking to occur. It is
+equivalent to (?!) but easier to read. The Perl documentation notes that it is
+probably useful only when combined with (?{}) or (??{}). Those are, of course,
+Perl features that are not present in PCRE. The nearest equivalent is the
+callout feature, as for example in this pattern:
+.sp
+  a+(?C)(*FAIL)
+.sp
+A match with the string "aaaa" always fails, but the callout is taken before
+each backtrack happens (in this example, 10 times).
+.
+.
+.SS "Recording which path was taken"
+.rs
+.sp
+There is one verb whose main purpose is to track how a match was arrived at,
+though it also has a secondary use in conjunction with advancing the match
+starting point (see (*SKIP) below).
+.sp
+  (*MARK:NAME) or (*:NAME)
+.sp
+A name is always required with this verb. There may be as many instances of
+(*MARK) as you like in a pattern, and their names do not have to be unique.
+.P
+When a match succeeds, the name of the last-encountered (*MARK:NAME),
+(*PRUNE:NAME), or (*THEN:NAME) on the matching path is passed back to the
+caller as described in the section entitled
+.\" HTML <a href="pcreapi.html#extradata">
+.\" </a>
+"Extra data for \fBpcre_exec()\fP"
+.\"
+in the
+.\" HREF
+\fBpcreapi\fP
+.\"
+documentation. Here is an example of \fBpcretest\fP output, where the /K
+modifier requests the retrieval and outputting of (*MARK) data:
+.sp
+    re> /X(*MARK:A)Y|X(*MARK:B)Z/K
+  data> XY
+   0: XY
+  MK: A
+  XZ
+   0: XZ
+  MK: B
+.sp
+The (*MARK) name is tagged with "MK:" in this output, and in this example it
+indicates which of the two alternatives matched. This is a more efficient way
+of obtaining this information than putting each alternative in its own
+capturing parentheses.
+.P
+If a verb with a name is encountered in a positive assertion that is true, the
+name is recorded and passed back if it is the last-encountered. This does not
+happen for negative assertions or failing positive assertions.
+.P
+After a partial match or a failed match, the last encountered name in the
+entire match process is returned. For example:
+.sp
+    re> /X(*MARK:A)Y|X(*MARK:B)Z/K
+  data> XP
+  No match, mark = B
+.sp
+Note that in this unanchored example the mark is retained from the match
+attempt that started at the letter "X" in the subject. Subsequent match
+attempts starting at "P" and then with an empty string do not get as far as the
+(*MARK) item, but nevertheless do not reset it.
+.P
+If you are interested in (*MARK) values after failed matches, you should
+probably set the PCRE_NO_START_OPTIMIZE option
+.\" HTML <a href="#nooptimize">
+.\" </a>
+(see above)
+.\"
+to ensure that the match is always attempted.
+.
+.
+.SS "Verbs that act after backtracking"
+.rs
+.sp
+The following verbs do nothing when they are encountered. Matching continues
+with what follows, but if there is no subsequent match, causing a backtrack to
+the verb, a failure is forced. That is, backtracking cannot pass to the left of
+the verb. However, when one of these verbs appears inside an atomic group or an
+assertion that is true, its effect is confined to that group, because once the
+group has been matched, there is never any backtracking into it. In this
+situation, backtracking can "jump back" to the left of the entire atomic group
+or assertion. (Remember also, as stated above, that this localization also
+applies in subroutine calls.)
+.P
+These verbs differ in exactly what kind of failure occurs when backtracking
+reaches them. The behaviour described below is what happens when the verb is
+not in a subroutine or an assertion. Subsequent sections cover these special
+cases.
+.sp
+  (*COMMIT)
+.sp
+This verb, which may not be followed by a name, causes the whole match to fail
+outright if there is a later matching failure that causes backtracking to reach
+it. Even if the pattern is unanchored, no further attempts to find a match by
+advancing the starting point take place. If (*COMMIT) is the only backtracking
+verb that is encountered, once it has been passed \fBpcre_exec()\fP is
+committed to finding a match at the current starting point, or not at all. For
+example:
+.sp
+  a+(*COMMIT)b
+.sp
+This matches "xxaab" but not "aacaab". It can be thought of as a kind of
+dynamic anchor, or "I've started, so I must finish." The name of the most
+recently passed (*MARK) in the path is passed back when (*COMMIT) forces a
+match failure.
+.P
+If there is more than one backtracking verb in a pattern, a different one that
+follows (*COMMIT) may be triggered first, so merely passing (*COMMIT) during a
+match does not always guarantee that a match must be at this starting point.
+.P
+Note that (*COMMIT) at the start of a pattern is not the same as an anchor,
+unless PCRE's start-of-match optimizations are turned off, as shown in this
+output from \fBpcretest\fP:
+.sp
+    re> /(*COMMIT)abc/
+  data> xyzabc
+   0: abc
+  data> xyzabc\eY
+  No match
+.sp
+For this pattern, PCRE knows that any match must start with "a", so the
+optimization skips along the subject to "a" before applying the pattern to the
+first set of data. The match attempt then succeeds. In the second set of data,
+the escape sequence \eY is interpreted by the \fBpcretest\fP program. It causes
+the PCRE_NO_START_OPTIMIZE option to be set when \fBpcre_exec()\fP is called.
+This disables the optimization that skips along to the first character. The
+pattern is now applied starting at "x", and so the (*COMMIT) causes the match
+to fail without trying any other starting points.
+.sp
+  (*PRUNE) or (*PRUNE:NAME)
+.sp
+This verb causes the match to fail at the current starting position in the
+subject if there is a later matching failure that causes backtracking to reach
+it. If the pattern is unanchored, the normal "bumpalong" advance to the next
+starting character then happens. Backtracking can occur as usual to the left of
+(*PRUNE), before it is reached, or when matching to the right of (*PRUNE), but
+if there is no match to the right, backtracking cannot cross (*PRUNE). In
+simple cases, the use of (*PRUNE) is just an alternative to an atomic group or
+possessive quantifier, but there are some uses of (*PRUNE) that cannot be
+expressed in any other way. In an anchored pattern (*PRUNE) has the same effect
+as (*COMMIT).
+.P
+The behaviour of (*PRUNE:NAME) is the not the same as (*MARK:NAME)(*PRUNE).
+It is like (*MARK:NAME) in that the name is remembered for passing back to the
+caller. However, (*SKIP:NAME) searches only for names set with (*MARK).
+.sp
+  (*SKIP)
+.sp
+This verb, when given without a name, is like (*PRUNE), except that if the
+pattern is unanchored, the "bumpalong" advance is not to the next character,
+but to the position in the subject where (*SKIP) was encountered. (*SKIP)
+signifies that whatever text was matched leading up to it cannot be part of a
+successful match. Consider:
+.sp
+  a+(*SKIP)b
+.sp
+If the subject is "aaaac...", after the first match attempt fails (starting at
+the first character in the string), the starting point skips on to start the
+next attempt at "c". Note that a possessive quantifer does not have the same
+effect as this example; although it would suppress backtracking during the
+first match attempt, the second attempt would start at the second character
+instead of skipping on to "c".
+.sp
+  (*SKIP:NAME)
+.sp
+When (*SKIP) has an associated name, its behaviour is modified. When it is
+triggered, the previous path through the pattern is searched for the most
+recent (*MARK) that has the same name. If one is found, the "bumpalong" advance
+is to the subject position that corresponds to that (*MARK) instead of to where
+(*SKIP) was encountered. If no (*MARK) with a matching name is found, the
+(*SKIP) is ignored.
+.P
+Note that (*SKIP:NAME) searches only for names set by (*MARK:NAME). It ignores
+names that are set by (*PRUNE:NAME) or (*THEN:NAME).
+.sp
+  (*THEN) or (*THEN:NAME)
+.sp
+This verb causes a skip to the next innermost alternative when backtracking
+reaches it. That is, it cancels any further backtracking within the current
+alternative. Its name comes from the observation that it can be used for a
+pattern-based if-then-else block:
+.sp
+  ( COND1 (*THEN) FOO | COND2 (*THEN) BAR | COND3 (*THEN) BAZ ) ...
+.sp
+If the COND1 pattern matches, FOO is tried (and possibly further items after
+the end of the group if FOO succeeds); on failure, the matcher skips to the
+second alternative and tries COND2, without backtracking into COND1. If that
+succeeds and BAR fails, COND3 is tried. If subsequently BAZ fails, there are no
+more alternatives, so there is a backtrack to whatever came before the entire
+group. If (*THEN) is not inside an alternation, it acts like (*PRUNE).
+.P
+The behaviour of (*THEN:NAME) is the not the same as (*MARK:NAME)(*THEN).
+It is like (*MARK:NAME) in that the name is remembered for passing back to the
+caller. However, (*SKIP:NAME) searches only for names set with (*MARK).
+.P
+A subpattern that does not contain a | character is just a part of the
+enclosing alternative; it is not a nested alternation with only one
+alternative. The effect of (*THEN) extends beyond such a subpattern to the
+enclosing alternative. Consider this pattern, where A, B, etc. are complex
+pattern fragments that do not contain any | characters at this level:
+.sp
+  A (B(*THEN)C) | D
+.sp
+If A and B are matched, but there is a failure in C, matching does not
+backtrack into A; instead it moves to the next alternative, that is, D.
+However, if the subpattern containing (*THEN) is given an alternative, it
+behaves differently:
+.sp
+  A (B(*THEN)C | (*FAIL)) | D
+.sp
+The effect of (*THEN) is now confined to the inner subpattern. After a failure
+in C, matching moves to (*FAIL), which causes the whole subpattern to fail
+because there are no more alternatives to try. In this case, matching does now
+backtrack into A.
+.P
+Note that a conditional subpattern is not considered as having two
+alternatives, because only one is ever used. In other words, the | character in
+a conditional subpattern has a different meaning. Ignoring white space,
+consider:
+.sp
+  ^.*? (?(?=a) a | b(*THEN)c )
+.sp
+If the subject is "ba", this pattern does not match. Because .*? is ungreedy,
+it initially matches zero characters. The condition (?=a) then fails, the
+character "b" is matched, but "c" is not. At this point, matching does not
+backtrack to .*? as might perhaps be expected from the presence of the |
+character. The conditional subpattern is part of the single alternative that
+comprises the whole pattern, and so the match fails. (If there was a backtrack
+into .*?, allowing it to match "b", the match would succeed.)
+.P
+The verbs just described provide four different "strengths" of control when
+subsequent matching fails. (*THEN) is the weakest, carrying on the match at the
+next alternative. (*PRUNE) comes next, failing the match at the current
+starting position, but allowing an advance to the next character (for an
+unanchored pattern). (*SKIP) is similar, except that the advance may be more
+than one character. (*COMMIT) is the strongest, causing the entire match to
+fail.
+.
+.
+.SS "More than one backtracking verb"
+.rs
+.sp
+If more than one backtracking verb is present in a pattern, the one that is
+backtracked onto first acts. For example, consider this pattern, where A, B,
+etc. are complex pattern fragments:
+.sp
+  (A(*COMMIT)B(*THEN)C|ABD)
+.sp
+If A matches but B fails, the backtrack to (*COMMIT) causes the entire match to
+fail. However, if A and B match, but C fails, the backtrack to (*THEN) causes
+the next alternative (ABD) to be tried. This behaviour is consistent, but is
+not always the same as Perl's. It means that if two or more backtracking verbs
+appear in succession, all the the last of them has no effect. Consider this
+example:
+.sp
+  ...(*COMMIT)(*PRUNE)...
+.sp
+If there is a matching failure to the right, backtracking onto (*PRUNE) causes
+it to be triggered, and its action is taken. There can never be a backtrack
+onto (*COMMIT).
+.
+.
+.\" HTML <a name="btrepeat"></a>
+.SS "Backtracking verbs in repeated groups"
+.rs
+.sp
+PCRE differs from Perl in its handling of backtracking verbs in repeated
+groups. For example, consider:
+.sp
+  /(a(*COMMIT)b)+ac/
+.sp
+If the subject is "abac", Perl matches, but PCRE fails because the (*COMMIT) in
+the second repeat of the group acts.
+.
+.
+.\" HTML <a name="btassert"></a>
+.SS "Backtracking verbs in assertions"
+.rs
+.sp
+(*FAIL) in an assertion has its normal effect: it forces an immediate backtrack.
+.P
+(*ACCEPT) in a positive assertion causes the assertion to succeed without any
+further processing. In a negative assertion, (*ACCEPT) causes the assertion to
+fail without any further processing.
+.P
+The other backtracking verbs are not treated specially if they appear in a
+positive assertion. In particular, (*THEN) skips to the next alternative in the
+innermost enclosing group that has alternations, whether or not this is within
+the assertion.
+.P
+Negative assertions are, however, different, in order to ensure that changing a
+positive assertion into a negative assertion changes its result. Backtracking
+into (*COMMIT), (*SKIP), or (*PRUNE) causes a negative assertion to be true,
+without considering any further alternative branches in the assertion.
+Backtracking into (*THEN) causes it to skip to the next enclosing alternative
+within the assertion (the normal behaviour), but if the assertion does not have
+such an alternative, (*THEN) behaves like (*PRUNE).
+.
+.
+.\" HTML <a name="btsub"></a>
+.SS "Backtracking verbs in subroutines"
+.rs
+.sp
+These behaviours occur whether or not the subpattern is called recursively.
+Perl's treatment of subroutines is different in some cases.
+.P
+(*FAIL) in a subpattern called as a subroutine has its normal effect: it forces
+an immediate backtrack.
+.P
+(*ACCEPT) in a subpattern called as a subroutine causes the subroutine match to
+succeed without any further processing. Matching then continues after the
+subroutine call.
+.P
+(*COMMIT), (*SKIP), and (*PRUNE) in a subpattern called as a subroutine cause
+the subroutine match to fail.
+.P
+(*THEN) skips to the next alternative in the innermost enclosing group within
+the subpattern that has alternatives. If there is no such group within the
+subpattern, (*THEN) causes the subroutine match to fail.
+.
+.
+.SH "SEE ALSO"
+.rs
+.sp
+\fBpcreapi\fP(3), \fBpcrecallout\fP(3), \fBpcrematching\fP(3),
+\fBpcresyntax\fP(3), \fBpcre\fP(3), \fBpcre16(3)\fP, \fBpcre32(3)\fP.
+.
+.
+.SH AUTHOR
+.rs
+.sp
+.nf
+Philip Hazel
+University Computing Service
+Cambridge CB2 3QH, England.
+.fi
+.
+.
+.SH REVISION
+.rs
+.sp
+.nf
+Last updated: 08 January 2014
+Copyright (c) 1997-2014 University of Cambridge.
+.fi
diff --git a/libs/Pcre16/docs/doc/pcreperform.3 b/libs/Pcre16/docs/doc/pcreperform.3
new file mode 100644
index 0000000000..fb2aa95926
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcreperform.3
@@ -0,0 +1,177 @@
+.TH PCREPERFORM 3 "09 January 2012" "PCRE 8.30"
+.SH NAME
+PCRE - Perl-compatible regular expressions
+.SH "PCRE PERFORMANCE"
+.rs
+.sp
+Two aspects of performance are discussed below: memory usage and processing
+time. The way you express your pattern as a regular expression can affect both
+of them.
+.
+.SH "COMPILED PATTERN MEMORY USAGE"
+.rs
+.sp
+Patterns are compiled by PCRE into a reasonably efficient interpretive code, so
+that most simple patterns do not use much memory. However, there is one case
+where the memory usage of a compiled pattern can be unexpectedly large. If a
+parenthesized subpattern has a quantifier with a minimum greater than 1 and/or
+a limited maximum, the whole subpattern is repeated in the compiled code. For
+example, the pattern
+.sp
+  (abc|def){2,4}
+.sp
+is compiled as if it were
+.sp
+  (abc|def)(abc|def)((abc|def)(abc|def)?)?
+.sp
+(Technical aside: It is done this way so that backtrack points within each of
+the repetitions can be independently maintained.)
+.P
+For regular expressions whose quantifiers use only small numbers, this is not
+usually a problem. However, if the numbers are large, and particularly if such
+repetitions are nested, the memory usage can become an embarrassment. For
+example, the very simple pattern
+.sp
+  ((ab){1,1000}c){1,3}
+.sp
+uses 51K bytes when compiled using the 8-bit library. When PCRE is compiled
+with its default internal pointer size of two bytes, the size limit on a
+compiled pattern is 64K data units, and this is reached with the above pattern
+if the outer repetition is increased from 3 to 4. PCRE can be compiled to use
+larger internal pointers and thus handle larger compiled patterns, but it is
+better to try to rewrite your pattern to use less memory if you can.
+.P
+One way of reducing the memory usage for such patterns is to make use of PCRE's
+.\" HTML <a href="pcrepattern.html#subpatternsassubroutines">
+.\" </a>
+"subroutine"
+.\"
+facility. Re-writing the above pattern as
+.sp
+  ((ab)(?2){0,999}c)(?1){0,2}
+.sp
+reduces the memory requirements to 18K, and indeed it remains under 20K even
+with the outer repetition increased to 100. However, this pattern is not
+exactly equivalent, because the "subroutine" calls are treated as
+.\" HTML <a href="pcrepattern.html#atomicgroup">
+.\" </a>
+atomic groups
+.\"
+into which there can be no backtracking if there is a subsequent matching
+failure. Therefore, PCRE cannot do this kind of rewriting automatically.
+Furthermore, there is a noticeable loss of speed when executing the modified
+pattern. Nevertheless, if the atomic grouping is not a problem and the loss of
+speed is acceptable, this kind of rewriting will allow you to process patterns
+that PCRE cannot otherwise handle.
+.
+.
+.SH "STACK USAGE AT RUN TIME"
+.rs
+.sp
+When \fBpcre_exec()\fP or \fBpcre[16|32]_exec()\fP is used for matching, certain
+kinds of pattern can cause it to use large amounts of the process stack. In
+some environments the default process stack is quite small, and if it runs out
+the result is often SIGSEGV. This issue is probably the most frequently raised
+problem with PCRE. Rewriting your pattern can often help. The
+.\" HREF
+\fBpcrestack\fP
+.\"
+documentation discusses this issue in detail.
+.
+.
+.SH "PROCESSING TIME"
+.rs
+.sp
+Certain items in regular expression patterns are processed more efficiently
+than others. It is more efficient to use a character class like [aeiou] than a
+set of single-character alternatives such as (a|e|i|o|u). In general, the
+simplest construction that provides the required behaviour is usually the most
+efficient. Jeffrey Friedl's book contains a lot of useful general discussion
+about optimizing regular expressions for efficient performance. This document
+contains a few observations about PCRE.
+.P
+Using Unicode character properties (the \ep, \eP, and \eX escapes) is slow,
+because PCRE has to use a multi-stage table lookup whenever it needs a
+character's property. If you can find an alternative pattern that does not use
+character properties, it will probably be faster.
+.P
+By default, the escape sequences \eb, \ed, \es, and \ew, and the POSIX
+character classes such as [:alpha:] do not use Unicode properties, partly for
+backwards compatibility, and partly for performance reasons. However, you can
+set PCRE_UCP if you want Unicode character properties to be used. This can
+double the matching time for items such as \ed, when matched with
+a traditional matching function; the performance loss is less with
+a DFA matching function, and in both cases there is not much difference for
+\eb.
+.P
+When a pattern begins with .* not in parentheses, or in parentheses that are
+not the subject of a backreference, and the PCRE_DOTALL option is set, the
+pattern is implicitly anchored by PCRE, since it can match only at the start of
+a subject string. However, if PCRE_DOTALL is not set, PCRE cannot make this
+optimization, because the . metacharacter does not then match a newline, and if
+the subject string contains newlines, the pattern may match from the character
+immediately following one of them instead of from the very start. For example,
+the pattern
+.sp
+  .*second
+.sp
+matches the subject "first\enand second" (where \en stands for a newline
+character), with the match starting at the seventh character. In order to do
+this, PCRE has to retry the match starting after every newline in the subject.
+.P
+If you are using such a pattern with subject strings that do not contain
+newlines, the best performance is obtained by setting PCRE_DOTALL, or starting
+the pattern with ^.* or ^.*? to indicate explicit anchoring. That saves PCRE
+from having to scan along the subject looking for a newline to restart at.
+.P
+Beware of patterns that contain nested indefinite repeats. These can take a
+long time to run when applied to a string that does not match. Consider the
+pattern fragment
+.sp
+  ^(a+)*
+.sp
+This can match "aaaa" in 16 different ways, and this number increases very
+rapidly as the string gets longer. (The * repeat can match 0, 1, 2, 3, or 4
+times, and for each of those cases other than 0 or 4, the + repeats can match
+different numbers of times.) When the remainder of the pattern is such that the
+entire match is going to fail, PCRE has in principle to try every possible
+variation, and this can take an extremely long time, even for relatively short
+strings.
+.P
+An optimization catches some of the more simple cases such as
+.sp
+  (a+)*b
+.sp
+where a literal character follows. Before embarking on the standard matching
+procedure, PCRE checks that there is a "b" later in the subject string, and if
+there is not, it fails the match immediately. However, when there is no
+following literal this optimization cannot be used. You can see the difference
+by comparing the behaviour of
+.sp
+  (a+)*\ed
+.sp
+with the pattern above. The former gives a failure almost instantly when
+applied to a whole line of "a" characters, whereas the latter takes an
+appreciable time with strings longer than about 20 characters.
+.P
+In many cases, the solution to this kind of performance issue is to use an
+atomic group or a possessive quantifier.
+.
+.
+.SH AUTHOR
+.rs
+.sp
+.nf
+Philip Hazel
+University Computing Service
+Cambridge CB2 3QH, England.
+.fi
+.
+.
+.SH REVISION
+.rs
+.sp
+.nf
+Last updated: 25 August 2012
+Copyright (c) 1997-2012 University of Cambridge.
+.fi
diff --git a/libs/Pcre16/docs/doc/pcreposix.3 b/libs/Pcre16/docs/doc/pcreposix.3
new file mode 100644
index 0000000000..77890f36b4
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcreposix.3
@@ -0,0 +1,267 @@
+.TH PCREPOSIX 3 "09 January 2012" "PCRE 8.30"
+.SH NAME
+PCRE - Perl-compatible regular expressions.
+.SH "SYNOPSIS"
+.rs
+.sp
+.B #include <pcreposix.h>
+.PP
+.nf
+.B int regcomp(regex_t *\fIpreg\fP, const char *\fIpattern\fP,
+.B "     int \fIcflags\fP);"
+.sp
+.B int regexec(regex_t *\fIpreg\fP, const char *\fIstring\fP,
+.B "     size_t \fInmatch\fP, regmatch_t \fIpmatch\fP[], int \fIeflags\fP);"
+.B "     size_t regerror(int \fIerrcode\fP, const regex_t *\fIpreg\fP,"
+.B "     char *\fIerrbuf\fP, size_t \fIerrbuf_size\fP);"
+.sp
+.B void regfree(regex_t *\fIpreg\fP);
+.fi
+.
+.SH DESCRIPTION
+.rs
+.sp
+This set of functions provides a POSIX-style API for the PCRE regular
+expression 8-bit library. See the
+.\" HREF
+\fBpcreapi\fP
+.\"
+documentation for a description of PCRE's native API, which contains much
+additional functionality. There is no POSIX-style wrapper for PCRE's 16-bit
+and 32-bit library.
+.P
+The functions described here are just wrapper functions that ultimately call
+the PCRE native API. Their prototypes are defined in the \fBpcreposix.h\fP
+header file, and on Unix systems the library itself is called
+\fBpcreposix.a\fP, so can be accessed by adding \fB-lpcreposix\fP to the
+command for linking an application that uses them. Because the POSIX functions
+call the native ones, it is also necessary to add \fB-lpcre\fP.
+.P
+I have implemented only those POSIX option bits that can be reasonably mapped
+to PCRE native options. In addition, the option REG_EXTENDED is defined with
+the value zero. This has no effect, but since programs that are written to the
+POSIX interface often use it, this makes it easier to slot in PCRE as a
+replacement library. Other POSIX options are not even defined.
+.P
+There are also some other options that are not defined by POSIX. These have
+been added at the request of users who want to make use of certain
+PCRE-specific features via the POSIX calling interface.
+.P
+When PCRE is called via these functions, it is only the API that is POSIX-like
+in style. The syntax and semantics of the regular expressions themselves are
+still those of Perl, subject to the setting of various PCRE options, as
+described below. "POSIX-like in style" means that the API approximates to the
+POSIX definition; it is not fully POSIX-compatible, and in multi-byte encoding
+domains it is probably even less compatible.
+.P
+The header for these functions is supplied as \fBpcreposix.h\fP to avoid any
+potential clash with other POSIX libraries. It can, of course, be renamed or
+aliased as \fBregex.h\fP, which is the "correct" name. It provides two
+structure types, \fIregex_t\fP for compiled internal forms, and
+\fIregmatch_t\fP for returning captured substrings. It also defines some
+constants whose names start with "REG_"; these are used for setting options and
+identifying error codes.
+.
+.
+.SH "COMPILING A PATTERN"
+.rs
+.sp
+The function \fBregcomp()\fP is called to compile a pattern into an
+internal form. The pattern is a C string terminated by a binary zero, and
+is passed in the argument \fIpattern\fP. The \fIpreg\fP argument is a pointer
+to a \fBregex_t\fP structure that is used as a base for storing information
+about the compiled regular expression.
+.P
+The argument \fIcflags\fP is either zero, or contains one or more of the bits
+defined by the following macros:
+.sp
+  REG_DOTALL
+.sp
+The PCRE_DOTALL option is set when the regular expression is passed for
+compilation to the native function. Note that REG_DOTALL is not part of the
+POSIX standard.
+.sp
+  REG_ICASE
+.sp
+The PCRE_CASELESS option is set when the regular expression is passed for
+compilation to the native function.
+.sp
+  REG_NEWLINE
+.sp
+The PCRE_MULTILINE option is set when the regular expression is passed for
+compilation to the native function. Note that this does \fInot\fP mimic the
+defined POSIX behaviour for REG_NEWLINE (see the following section).
+.sp
+  REG_NOSUB
+.sp
+The PCRE_NO_AUTO_CAPTURE option is set when the regular expression is passed
+for compilation to the native function. In addition, when a pattern that is
+compiled with this flag is passed to \fBregexec()\fP for matching, the
+\fInmatch\fP and \fIpmatch\fP arguments are ignored, and no captured strings
+are returned.
+.sp
+  REG_UCP
+.sp
+The PCRE_UCP option is set when the regular expression is passed for
+compilation to the native function. This causes PCRE to use Unicode properties
+when matchine \ed, \ew, etc., instead of just recognizing ASCII values. Note
+that REG_UTF8 is not part of the POSIX standard.
+.sp
+  REG_UNGREEDY
+.sp
+The PCRE_UNGREEDY option is set when the regular expression is passed for
+compilation to the native function. Note that REG_UNGREEDY is not part of the
+POSIX standard.
+.sp
+  REG_UTF8
+.sp
+The PCRE_UTF8 option is set when the regular expression is passed for
+compilation to the native function. This causes the pattern itself and all data
+strings used for matching it to be treated as UTF-8 strings. Note that REG_UTF8
+is not part of the POSIX standard.
+.P
+In the absence of these flags, no options are passed to the native function.
+This means the the regex is compiled with PCRE default semantics. In
+particular, the way it handles newline characters in the subject string is the
+Perl way, not the POSIX way. Note that setting PCRE_MULTILINE has only
+\fIsome\fP of the effects specified for REG_NEWLINE. It does not affect the way
+newlines are matched by . (they are not) or by a negative class such as [^a]
+(they are).
+.P
+The yield of \fBregcomp()\fP is zero on success, and non-zero otherwise. The
+\fIpreg\fP structure is filled in on success, and one member of the structure
+is public: \fIre_nsub\fP contains the number of capturing subpatterns in
+the regular expression. Various error codes are defined in the header file.
+.P
+NOTE: If the yield of \fBregcomp()\fP is non-zero, you must not attempt to
+use the contents of the \fIpreg\fP structure. If, for example, you pass it to
+\fBregexec()\fP, the result is undefined and your program is likely to crash.
+.
+.
+.SH "MATCHING NEWLINE CHARACTERS"
+.rs
+.sp
+This area is not simple, because POSIX and Perl take different views of things.
+It is not possible to get PCRE to obey POSIX semantics, but then PCRE was never
+intended to be a POSIX engine. The following table lists the different
+possibilities for matching newline characters in PCRE:
+.sp
+                          Default   Change with
+.sp
+  . matches newline          no     PCRE_DOTALL
+  newline matches [^a]       yes    not changeable
+  $ matches \en at end        yes    PCRE_DOLLARENDONLY
+  $ matches \en in middle     no     PCRE_MULTILINE
+  ^ matches \en in middle     no     PCRE_MULTILINE
+.sp
+This is the equivalent table for POSIX:
+.sp
+                          Default   Change with
+.sp
+  . matches newline          yes    REG_NEWLINE
+  newline matches [^a]       yes    REG_NEWLINE
+  $ matches \en at end        no     REG_NEWLINE
+  $ matches \en in middle     no     REG_NEWLINE
+  ^ matches \en in middle     no     REG_NEWLINE
+.sp
+PCRE's behaviour is the same as Perl's, except that there is no equivalent for
+PCRE_DOLLAR_ENDONLY in Perl. In both PCRE and Perl, there is no way to stop
+newline from matching [^a].
+.P
+The default POSIX newline handling can be obtained by setting PCRE_DOTALL and
+PCRE_DOLLAR_ENDONLY, but there is no way to make PCRE behave exactly as for the
+REG_NEWLINE action.
+.
+.
+.SH "MATCHING A PATTERN"
+.rs
+.sp
+The function \fBregexec()\fP is called to match a compiled pattern \fIpreg\fP
+against a given \fIstring\fP, which is by default terminated by a zero byte
+(but see REG_STARTEND below), subject to the options in \fIeflags\fP. These can
+be:
+.sp
+  REG_NOTBOL
+.sp
+The PCRE_NOTBOL option is set when calling the underlying PCRE matching
+function.
+.sp
+  REG_NOTEMPTY
+.sp
+The PCRE_NOTEMPTY option is set when calling the underlying PCRE matching
+function. Note that REG_NOTEMPTY is not part of the POSIX standard. However,
+setting this option can give more POSIX-like behaviour in some situations.
+.sp
+  REG_NOTEOL
+.sp
+The PCRE_NOTEOL option is set when calling the underlying PCRE matching
+function.
+.sp
+  REG_STARTEND
+.sp
+The string is considered to start at \fIstring\fP + \fIpmatch[0].rm_so\fP and
+to have a terminating NUL located at \fIstring\fP + \fIpmatch[0].rm_eo\fP
+(there need not actually be a NUL at that location), regardless of the value of
+\fInmatch\fP. This is a BSD extension, compatible with but not specified by
+IEEE Standard 1003.2 (POSIX.2), and should be used with caution in software
+intended to be portable to other systems. Note that a non-zero \fIrm_so\fP does
+not imply REG_NOTBOL; REG_STARTEND affects only the location of the string, not
+how it is matched.
+.P
+If the pattern was compiled with the REG_NOSUB flag, no data about any matched
+strings is returned. The \fInmatch\fP and \fIpmatch\fP arguments of
+\fBregexec()\fP are ignored.
+.P
+If the value of \fInmatch\fP is zero, or if the value \fIpmatch\fP is NULL,
+no data about any matched strings is returned.
+.P
+Otherwise,the portion of the string that was matched, and also any captured
+substrings, are returned via the \fIpmatch\fP argument, which points to an
+array of \fInmatch\fP structures of type \fIregmatch_t\fP, containing the
+members \fIrm_so\fP and \fIrm_eo\fP. These contain the offset to the first
+character of each substring and the offset to the first character after the end
+of each substring, respectively. The 0th element of the vector relates to the
+entire portion of \fIstring\fP that was matched; subsequent elements relate to
+the capturing subpatterns of the regular expression. Unused entries in the
+array have both structure members set to -1.
+.P
+A successful match yields a zero return; various error codes are defined in the
+header file, of which REG_NOMATCH is the "expected" failure code.
+.
+.
+.SH "ERROR MESSAGES"
+.rs
+.sp
+The \fBregerror()\fP function maps a non-zero errorcode from either
+\fBregcomp()\fP or \fBregexec()\fP to a printable message. If \fIpreg\fP is not
+NULL, the error should have arisen from the use of that structure. A message
+terminated by a binary zero is placed in \fIerrbuf\fP. The length of the
+message, including the zero, is limited to \fIerrbuf_size\fP. The yield of the
+function is the size of buffer needed to hold the whole message.
+.
+.
+.SH MEMORY USAGE
+.rs
+.sp
+Compiling a regular expression causes memory to be allocated and associated
+with the \fIpreg\fP structure. The function \fBregfree()\fP frees all such
+memory, after which \fIpreg\fP may no longer be used as a compiled expression.
+.
+.
+.SH AUTHOR
+.rs
+.sp
+.nf
+Philip Hazel
+University Computing Service
+Cambridge CB2 3QH, England.
+.fi
+.
+.
+.SH REVISION
+.rs
+.sp
+.nf
+Last updated: 09 January 2012
+Copyright (c) 1997-2012 University of Cambridge.
+.fi
diff --git a/libs/Pcre16/docs/doc/pcreprecompile.3 b/libs/Pcre16/docs/doc/pcreprecompile.3
new file mode 100644
index 0000000000..40f257a98c
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcreprecompile.3
@@ -0,0 +1,155 @@
+.TH PCREPRECOMPILE 3 "12 November 2013" "PCRE 8.34"
+.SH NAME
+PCRE - Perl-compatible regular expressions
+.SH "SAVING AND RE-USING PRECOMPILED PCRE PATTERNS"
+.rs
+.sp
+If you are running an application that uses a large number of regular
+expression patterns, it may be useful to store them in a precompiled form
+instead of having to compile them every time the application is run.
+If you are not using any private character tables (see the
+.\" HREF
+\fBpcre_maketables()\fP
+.\"
+documentation), this is relatively straightforward. If you are using private
+tables, it is a little bit more complicated. However, if you are using the
+just-in-time optimization feature, it is not possible to save and reload the
+JIT data.
+.P
+If you save compiled patterns to a file, you can copy them to a different host
+and run them there. If the two hosts have different endianness (byte order),
+you should run the \fBpcre[16|32]_pattern_to_host_byte_order()\fP function on the
+new host before trying to match the pattern. The matching functions return
+PCRE_ERROR_BADENDIANNESS if they detect a pattern with the wrong endianness.
+.P
+Compiling regular expressions with one version of PCRE for use with a different
+version is not guaranteed to work and may cause crashes, and saving and
+restoring a compiled pattern loses any JIT optimization data.
+.
+.
+.SH "SAVING A COMPILED PATTERN"
+.rs
+.sp
+The value returned by \fBpcre[16|32]_compile()\fP points to a single block of
+memory that holds the compiled pattern and associated data. You can find the
+length of this block in bytes by calling \fBpcre[16|32]_fullinfo()\fP with an
+argument of PCRE_INFO_SIZE. You can then save the data in any appropriate
+manner. Here is sample code for the 8-bit library that compiles a pattern and
+writes it to a file. It assumes that the variable \fIfd\fP refers to a file
+that is open for output:
+.sp
+  int erroroffset, rc, size;
+  char *error;
+  pcre *re;
+.sp
+  re = pcre_compile("my pattern", 0, &error, &erroroffset, NULL);
+  if (re == NULL) { ... handle errors ... }
+  rc = pcre_fullinfo(re, NULL, PCRE_INFO_SIZE, &size);
+  if (rc < 0) { ... handle errors ... }
+  rc = fwrite(re, 1, size, fd);
+  if (rc != size) { ... handle errors ... }
+.sp
+In this example, the bytes that comprise the compiled pattern are copied
+exactly. Note that this is binary data that may contain any of the 256 possible
+byte values. On systems that make a distinction between binary and non-binary
+data, be sure that the file is opened for binary output.
+.P
+If you want to write more than one pattern to a file, you will have to devise a
+way of separating them. For binary data, preceding each pattern with its length
+is probably the most straightforward approach. Another possibility is to write
+out the data in hexadecimal instead of binary, one pattern to a line.
+.P
+Saving compiled patterns in a file is only one possible way of storing them for
+later use. They could equally well be saved in a database, or in the memory of
+some daemon process that passes them via sockets to the processes that want
+them.
+.P
+If the pattern has been studied, it is also possible to save the normal study
+data in a similar way to the compiled pattern itself. However, if the
+PCRE_STUDY_JIT_COMPILE was used, the just-in-time data that is created cannot
+be saved because it is too dependent on the current environment. When studying
+generates additional information, \fBpcre[16|32]_study()\fP returns a pointer to a
+\fBpcre[16|32]_extra\fP data block. Its format is defined in the
+.\" HTML <a href="pcreapi.html#extradata">
+.\" </a>
+section on matching a pattern
+.\"
+in the
+.\" HREF
+\fBpcreapi\fP
+.\"
+documentation. The \fIstudy_data\fP field points to the binary study data, and
+this is what you must save (not the \fBpcre[16|32]_extra\fP block itself). The
+length of the study data can be obtained by calling \fBpcre[16|32]_fullinfo()\fP
+with an argument of PCRE_INFO_STUDYSIZE. Remember to check that
+\fBpcre[16|32]_study()\fP did return a non-NULL value before trying to save the
+study data.
+.
+.
+.SH "RE-USING A PRECOMPILED PATTERN"
+.rs
+.sp
+Re-using a precompiled pattern is straightforward. Having reloaded it into main
+memory, called \fBpcre[16|32]_pattern_to_host_byte_order()\fP if necessary, you
+pass its pointer to \fBpcre[16|32]_exec()\fP or \fBpcre[16|32]_dfa_exec()\fP in
+the usual way.
+.P
+However, if you passed a pointer to custom character tables when the pattern
+was compiled (the \fItableptr\fP argument of \fBpcre[16|32]_compile()\fP), you
+must now pass a similar pointer to \fBpcre[16|32]_exec()\fP or
+\fBpcre[16|32]_dfa_exec()\fP, because the value saved with the compiled pattern
+will obviously be nonsense. A field in a \fBpcre[16|32]_extra()\fP block is used
+to pass this data, as described in the
+.\" HTML <a href="pcreapi.html#extradata">
+.\" </a>
+section on matching a pattern
+.\"
+in the
+.\" HREF
+\fBpcreapi\fP
+.\"
+documentation.
+.P
+\fBWarning:\fP The tables that \fBpcre_exec()\fP and \fBpcre_dfa_exec()\fP use
+must be the same as those that were used when the pattern was compiled. If this
+is not the case, the behaviour is undefined.
+.P
+If you did not provide custom character tables when the pattern was compiled,
+the pointer in the compiled pattern is NULL, which causes the matching
+functions to use PCRE's internal tables. Thus, you do not need to take any
+special action at run time in this case.
+.P
+If you saved study data with the compiled pattern, you need to create your own
+\fBpcre[16|32]_extra\fP data block and set the \fIstudy_data\fP field to point
+to the reloaded study data. You must also set the PCRE_EXTRA_STUDY_DATA bit in
+the \fIflags\fP field to indicate that study data is present. Then pass the
+\fBpcre[16|32]_extra\fP block to the matching function in the usual way. If the
+pattern was studied for just-in-time optimization, that data cannot be saved,
+and so is lost by a save/restore cycle.
+.
+.
+.SH "COMPATIBILITY WITH DIFFERENT PCRE RELEASES"
+.rs
+.sp
+In general, it is safest to recompile all saved patterns when you update to a
+new PCRE release, though not all updates actually require this.
+.
+.
+.
+.SH AUTHOR
+.rs
+.sp
+.nf
+Philip Hazel
+University Computing Service
+Cambridge CB2 3QH, England.
+.fi
+.
+.
+.SH REVISION
+.rs
+.sp
+.nf
+Last updated: 12 November 2013
+Copyright (c) 1997-2013 University of Cambridge.
+.fi
diff --git a/libs/Pcre16/docs/doc/pcresample.3 b/libs/Pcre16/docs/doc/pcresample.3
new file mode 100644
index 0000000000..d7fe7ec546
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcresample.3
@@ -0,0 +1,99 @@
+.TH PCRESAMPLE 3 "10 January 2012" "PCRE 8.30"
+.SH NAME
+PCRE - Perl-compatible regular expressions
+.SH "PCRE SAMPLE PROGRAM"
+.rs
+.sp
+A simple, complete demonstration program, to get you started with using PCRE,
+is supplied in the file \fIpcredemo.c\fP in the PCRE distribution. A listing of
+this program is given in the
+.\" HREF
+\fBpcredemo\fP
+.\"
+documentation. If you do not have a copy of the PCRE distribution, you can save
+this listing to re-create \fIpcredemo.c\fP.
+.P
+The demonstration program, which uses the original PCRE 8-bit library, compiles
+the regular expression that is its first argument, and matches it against the
+subject string in its second argument. No PCRE options are set, and default
+character tables are used. If matching succeeds, the program outputs the
+portion of the subject that matched, together with the contents of any captured
+substrings.
+.P
+If the -g option is given on the command line, the program then goes on to
+check for further matches of the same regular expression in the same subject
+string. The logic is a little bit tricky because of the possibility of matching
+an empty string. Comments in the code explain what is going on.
+.P
+If PCRE is installed in the standard include and library directories for your
+operating system, you should be able to compile the demonstration program using
+this command:
+.sp
+  gcc -o pcredemo pcredemo.c -lpcre
+.sp
+If PCRE is installed elsewhere, you may need to add additional options to the
+command line. For example, on a Unix-like system that has PCRE installed in
+\fI/usr/local\fP, you can compile the demonstration program using a command
+like this:
+.sp
+.\" JOINSH
+  gcc -o pcredemo -I/usr/local/include pcredemo.c \e
+      -L/usr/local/lib -lpcre
+.sp
+In a Windows environment, if you want to statically link the program against a
+non-dll \fBpcre.a\fP file, you must uncomment the line that defines PCRE_STATIC
+before including \fBpcre.h\fP, because otherwise the \fBpcre_malloc()\fP and
+\fBpcre_free()\fP exported functions will be declared
+\fB__declspec(dllimport)\fP, with unwanted results.
+.P
+Once you have compiled and linked the demonstration program, you can run simple
+tests like this:
+.sp
+  ./pcredemo 'cat|dog' 'the cat sat on the mat'
+  ./pcredemo -g 'cat|dog' 'the dog sat on the cat'
+.sp
+Note that there is a much more comprehensive test program, called
+.\" HREF
+\fBpcretest\fP,
+.\"
+which supports many more facilities for testing regular expressions and both
+PCRE libraries. The
+.\" HREF
+\fBpcredemo\fP
+.\"
+program is provided as a simple coding example.
+.P
+If you try to run
+.\" HREF
+\fBpcredemo\fP
+.\"
+when PCRE is not installed in the standard library directory, you may get an
+error like this on some operating systems (e.g. Solaris):
+.sp
+  ld.so.1: a.out: fatal: libpcre.so.0: open failed: No such file or directory
+.sp
+This is caused by the way shared library support works on those systems. You
+need to add
+.sp
+  -R/usr/local/lib
+.sp
+(for example) to the compile command to get round this problem.
+.
+.
+.SH AUTHOR
+.rs
+.sp
+.nf
+Philip Hazel
+University Computing Service
+Cambridge CB2 3QH, England.
+.fi
+.
+.
+.SH REVISION
+.rs
+.sp
+.nf
+Last updated: 10 January 2012
+Copyright (c) 1997-2012 University of Cambridge.
+.fi
diff --git a/libs/Pcre16/docs/doc/pcrestack.3 b/libs/Pcre16/docs/doc/pcrestack.3
new file mode 100644
index 0000000000..798f0bca63
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcrestack.3
@@ -0,0 +1,215 @@
+.TH PCRESTACK 3 "24 June 2012" "PCRE 8.30"
+.SH NAME
+PCRE - Perl-compatible regular expressions
+.SH "PCRE DISCUSSION OF STACK USAGE"
+.rs
+.sp
+When you call \fBpcre[16|32]_exec()\fP, it makes use of an internal function
+called \fBmatch()\fP. This calls itself recursively at branch points in the
+pattern, in order to remember the state of the match so that it can back up and
+try a different alternative if the first one fails. As matching proceeds deeper
+and deeper into the tree of possibilities, the recursion depth increases. The
+\fBmatch()\fP function is also called in other circumstances, for example,
+whenever a parenthesized sub-pattern is entered, and in certain cases of
+repetition.
+.P
+Not all calls of \fBmatch()\fP increase the recursion depth; for an item such
+as a* it may be called several times at the same level, after matching
+different numbers of a's. Furthermore, in a number of cases where the result of
+the recursive call would immediately be passed back as the result of the
+current call (a "tail recursion"), the function is just restarted instead.
+.P
+The above comments apply when \fBpcre[16|32]_exec()\fP is run in its normal
+interpretive manner. If the pattern was studied with the
+PCRE_STUDY_JIT_COMPILE option, and just-in-time compiling was successful, and
+the options passed to \fBpcre[16|32]_exec()\fP were not incompatible, the matching
+process uses the JIT-compiled code instead of the \fBmatch()\fP function. In
+this case, the memory requirements are handled entirely differently. See the
+.\" HREF
+\fBpcrejit\fP
+.\"
+documentation for details.
+.P
+The \fBpcre[16|32]_dfa_exec()\fP function operates in an entirely different way,
+and uses recursion only when there is a regular expression recursion or
+subroutine call in the pattern. This includes the processing of assertion and
+"once-only" subpatterns, which are handled like subroutine calls. Normally,
+these are never very deep, and the limit on the complexity of
+\fBpcre[16|32]_dfa_exec()\fP is controlled by the amount of workspace it is given.
+However, it is possible to write patterns with runaway infinite recursions;
+such patterns will cause \fBpcre[16|32]_dfa_exec()\fP to run out of stack. At
+present, there is no protection against this.
+.P
+The comments that follow do NOT apply to \fBpcre[16|32]_dfa_exec()\fP; they are
+relevant only for \fBpcre[16|32]_exec()\fP without the JIT optimization.
+.
+.
+.SS "Reducing \fBpcre[16|32]_exec()\fP's stack usage"
+.rs
+.sp
+Each time that \fBmatch()\fP is actually called recursively, it uses memory
+from the process stack. For certain kinds of pattern and data, very large
+amounts of stack may be needed, despite the recognition of "tail recursion".
+You can often reduce the amount of recursion, and therefore the amount of stack
+used, by modifying the pattern that is being matched. Consider, for example,
+this pattern:
+.sp
+  ([^<]|<(?!inet))+
+.sp
+It matches from wherever it starts until it encounters "<inet" or the end of
+the data, and is the kind of pattern that might be used when processing an XML
+file. Each iteration of the outer parentheses matches either one character that
+is not "<" or a "<" that is not followed by "inet". However, each time a
+parenthesis is processed, a recursion occurs, so this formulation uses a stack
+frame for each matched character. For a long string, a lot of stack is
+required. Consider now this rewritten pattern, which matches exactly the same
+strings:
+.sp
+  ([^<]++|<(?!inet))+
+.sp
+This uses very much less stack, because runs of characters that do not contain
+"<" are "swallowed" in one item inside the parentheses. Recursion happens only
+when a "<" character that is not followed by "inet" is encountered (and we
+assume this is relatively rare). A possessive quantifier is used to stop any
+backtracking into the runs of non-"<" characters, but that is not related to
+stack usage.
+.P
+This example shows that one way of avoiding stack problems when matching long
+subject strings is to write repeated parenthesized subpatterns to match more
+than one character whenever possible.
+.
+.
+.SS "Compiling PCRE to use heap instead of stack for \fBpcre[16|32]_exec()\fP"
+.rs
+.sp
+In environments where stack memory is constrained, you might want to compile
+PCRE to use heap memory instead of stack for remembering back-up points when
+\fBpcre[16|32]_exec()\fP is running. This makes it run a lot more slowly, however.
+Details of how to do this are given in the
+.\" HREF
+\fBpcrebuild\fP
+.\"
+documentation. When built in this way, instead of using the stack, PCRE obtains
+and frees memory by calling the functions that are pointed to by the
+\fBpcre[16|32]_stack_malloc\fP and \fBpcre[16|32]_stack_free\fP variables. By
+default, these point to \fBmalloc()\fP and \fBfree()\fP, but you can replace
+the pointers to cause PCRE to use your own functions. Since the block sizes are
+always the same, and are always freed in reverse order, it may be possible to
+implement customized memory handlers that are more efficient than the standard
+functions.
+.
+.
+.SS "Limiting \fBpcre[16|32]_exec()\fP's stack usage"
+.rs
+.sp
+You can set limits on the number of times that \fBmatch()\fP is called, both in
+total and recursively. If a limit is exceeded, \fBpcre[16|32]_exec()\fP returns an
+error code. Setting suitable limits should prevent it from running out of
+stack. The default values of the limits are very large, and unlikely ever to
+operate. They can be changed when PCRE is built, and they can also be set when
+\fBpcre[16|32]_exec()\fP is called. For details of these interfaces, see the
+.\" HREF
+\fBpcrebuild\fP
+.\"
+documentation and the
+.\" HTML <a href="pcreapi.html#extradata">
+.\" </a>
+section on extra data for \fBpcre[16|32]_exec()\fP
+.\"
+in the
+.\" HREF
+\fBpcreapi\fP
+.\"
+documentation.
+.P
+As a very rough rule of thumb, you should reckon on about 500 bytes per
+recursion. Thus, if you want to limit your stack usage to 8Mb, you should set
+the limit at 16000 recursions. A 64Mb stack, on the other hand, can support
+around 128000 recursions.
+.P
+In Unix-like environments, the \fBpcretest\fP test program has a command line
+option (\fB-S\fP) that can be used to increase the size of its stack. As long
+as the stack is large enough, another option (\fB-M\fP) can be used to find the
+smallest limits that allow a particular pattern to match a given subject
+string. This is done by calling \fBpcre[16|32]_exec()\fP repeatedly with different
+limits.
+.
+.
+.SS "Obtaining an estimate of stack usage"
+.rs
+.sp
+The actual amount of stack used per recursion can vary quite a lot, depending
+on the compiler that was used to build PCRE and the optimization or debugging
+options that were set for it. The rule of thumb value of 500 bytes mentioned
+above may be larger or smaller than what is actually needed. A better
+approximation can be obtained by running this command:
+.sp
+  pcretest -m -C
+.sp
+The \fB-C\fP option causes \fBpcretest\fP to output information about the
+options with which PCRE was compiled. When \fB-m\fP is also given (before
+\fB-C\fP), information about stack use is given in a line like this:
+.sp
+  Match recursion uses stack: approximate frame size = 640 bytes
+.sp
+The value is approximate because some recursions need a bit more (up to perhaps
+16 more bytes).
+.P
+If the above command is given when PCRE is compiled to use the heap instead of
+the stack for recursion, the value that is output is the size of each block
+that is obtained from the heap.
+.
+.
+.SS "Changing stack size in Unix-like systems"
+.rs
+.sp
+In Unix-like environments, there is not often a problem with the stack unless
+very long strings are involved, though the default limit on stack size varies
+from system to system. Values from 8Mb to 64Mb are common. You can find your
+default limit by running the command:
+.sp
+  ulimit -s
+.sp
+Unfortunately, the effect of running out of stack is often SIGSEGV, though
+sometimes a more explicit error message is given. You can normally increase the
+limit on stack size by code such as this:
+.sp
+  struct rlimit rlim;
+  getrlimit(RLIMIT_STACK, &rlim);
+  rlim.rlim_cur = 100*1024*1024;
+  setrlimit(RLIMIT_STACK, &rlim);
+.sp
+This reads the current limits (soft and hard) using \fBgetrlimit()\fP, then
+attempts to increase the soft limit to 100Mb using \fBsetrlimit()\fP. You must
+do this before calling \fBpcre[16|32]_exec()\fP.
+.
+.
+.SS "Changing stack size in Mac OS X"
+.rs
+.sp
+Using \fBsetrlimit()\fP, as described above, should also work on Mac OS X. It
+is also possible to set a stack size when linking a program. There is a
+discussion about stack sizes in Mac OS X at this web site:
+.\" HTML <a href="http://developer.apple.com/qa/qa2005/qa1419.html">
+.\" </a>
+http://developer.apple.com/qa/qa2005/qa1419.html.
+.\"
+.
+.
+.SH AUTHOR
+.rs
+.sp
+.nf
+Philip Hazel
+University Computing Service
+Cambridge CB2 3QH, England.
+.fi
+.
+.
+.SH REVISION
+.rs
+.sp
+.nf
+Last updated: 24 June 2012
+Copyright (c) 1997-2012 University of Cambridge.
+.fi
diff --git a/libs/Pcre16/docs/doc/pcresyntax.3 b/libs/Pcre16/docs/doc/pcresyntax.3
new file mode 100644
index 0000000000..fd878da4f9
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcresyntax.3
@@ -0,0 +1,517 @@
+.TH PCRESYNTAX 3 "08 January 2014" "PCRE 8.35"
+.SH NAME
+PCRE - Perl-compatible regular expressions
+.SH "PCRE REGULAR EXPRESSION SYNTAX SUMMARY"
+.rs
+.sp
+The full syntax and semantics of the regular expressions that are supported by
+PCRE are described in the
+.\" HREF
+\fBpcrepattern\fP
+.\"
+documentation. This document contains a quick-reference summary of the syntax.
+.
+.
+.SH "QUOTING"
+.rs
+.sp
+  \ex         where x is non-alphanumeric is a literal x
+  \eQ...\eE    treat enclosed characters as literal
+.
+.
+.SH "CHARACTERS"
+.rs
+.sp
+  \ea         alarm, that is, the BEL character (hex 07)
+  \ecx        "control-x", where x is any ASCII character
+  \ee         escape (hex 1B)
+  \ef         form feed (hex 0C)
+  \en         newline (hex 0A)
+  \er         carriage return (hex 0D)
+  \et         tab (hex 09)
+  \e0dd       character with octal code 0dd
+  \eddd       character with octal code ddd, or backreference
+  \eo{ddd..}  character with octal code ddd..
+  \exhh       character with hex code hh
+  \ex{hhh..}  character with hex code hhh..
+.sp
+Note that \e0dd is always an octal code, and that \e8 and \e9 are the literal
+characters "8" and "9".
+.
+.
+.SH "CHARACTER TYPES"
+.rs
+.sp
+  .          any character except newline;
+               in dotall mode, any character whatsoever
+  \eC         one data unit, even in UTF mode (best avoided)
+  \ed         a decimal digit
+  \eD         a character that is not a decimal digit
+  \eh         a horizontal white space character
+  \eH         a character that is not a horizontal white space character
+  \eN         a character that is not a newline
+  \ep{\fIxx\fP}     a character with the \fIxx\fP property
+  \eP{\fIxx\fP}     a character without the \fIxx\fP property
+  \eR         a newline sequence
+  \es         a white space character
+  \eS         a character that is not a white space character
+  \ev         a vertical white space character
+  \eV         a character that is not a vertical white space character
+  \ew         a "word" character
+  \eW         a "non-word" character
+  \eX         a Unicode extended grapheme cluster
+.sp
+By default, \ed, \es, and \ew match only ASCII characters, even in UTF-8 mode
+or in the 16- bit and 32-bit libraries. However, if locale-specific matching is
+happening, \es and \ew may also match characters with code points in the range
+128-255. If the PCRE_UCP option is set, the behaviour of these escape sequences
+is changed to use Unicode properties and they match many more characters.
+.
+.
+.SH "GENERAL CATEGORY PROPERTIES FOR \ep and \eP"
+.rs
+.sp
+  C          Other
+  Cc         Control
+  Cf         Format
+  Cn         Unassigned
+  Co         Private use
+  Cs         Surrogate
+.sp
+  L          Letter
+  Ll         Lower case letter
+  Lm         Modifier letter
+  Lo         Other letter
+  Lt         Title case letter
+  Lu         Upper case letter
+  L&         Ll, Lu, or Lt
+.sp
+  M          Mark
+  Mc         Spacing mark
+  Me         Enclosing mark
+  Mn         Non-spacing mark
+.sp
+  N          Number
+  Nd         Decimal number
+  Nl         Letter number
+  No         Other number
+.sp
+  P          Punctuation
+  Pc         Connector punctuation
+  Pd         Dash punctuation
+  Pe         Close punctuation
+  Pf         Final punctuation
+  Pi         Initial punctuation
+  Po         Other punctuation
+  Ps         Open punctuation
+.sp
+  S          Symbol
+  Sc         Currency symbol
+  Sk         Modifier symbol
+  Sm         Mathematical symbol
+  So         Other symbol
+.sp
+  Z          Separator
+  Zl         Line separator
+  Zp         Paragraph separator
+  Zs         Space separator
+.
+.
+.SH "PCRE SPECIAL CATEGORY PROPERTIES FOR \ep and \eP"
+.rs
+.sp
+  Xan        Alphanumeric: union of properties L and N
+  Xps        POSIX space: property Z or tab, NL, VT, FF, CR
+  Xsp        Perl space: property Z or tab, NL, VT, FF, CR
+  Xuc        Univerally-named character: one that can be
+               represented by a Universal Character Name
+  Xwd        Perl word: property Xan or underscore
+.sp
+Perl and POSIX space are now the same. Perl added VT to its space character set
+at release 5.18 and PCRE changed at release 8.34.
+.
+.
+.SH "SCRIPT NAMES FOR \ep AND \eP"
+.rs
+.sp
+Arabic,
+Armenian,
+Avestan,
+Balinese,
+Bamum,
+Batak,
+Bengali,
+Bopomofo,
+Brahmi,
+Braille,
+Buginese,
+Buhid,
+Canadian_Aboriginal,
+Carian,
+Chakma,
+Cham,
+Cherokee,
+Common,
+Coptic,
+Cuneiform,
+Cypriot,
+Cyrillic,
+Deseret,
+Devanagari,
+Egyptian_Hieroglyphs,
+Ethiopic,
+Georgian,
+Glagolitic,
+Gothic,
+Greek,
+Gujarati,
+Gurmukhi,
+Han,
+Hangul,
+Hanunoo,
+Hebrew,
+Hiragana,
+Imperial_Aramaic,
+Inherited,
+Inscriptional_Pahlavi,
+Inscriptional_Parthian,
+Javanese,
+Kaithi,
+Kannada,
+Katakana,
+Kayah_Li,
+Kharoshthi,
+Khmer,
+Lao,
+Latin,
+Lepcha,
+Limbu,
+Linear_B,
+Lisu,
+Lycian,
+Lydian,
+Malayalam,
+Mandaic,
+Meetei_Mayek,
+Meroitic_Cursive,
+Meroitic_Hieroglyphs,
+Miao,
+Mongolian,
+Myanmar,
+New_Tai_Lue,
+Nko,
+Ogham,
+Old_Italic,
+Old_Persian,
+Old_South_Arabian,
+Old_Turkic,
+Ol_Chiki,
+Oriya,
+Osmanya,
+Phags_Pa,
+Phoenician,
+Rejang,
+Runic,
+Samaritan,
+Saurashtra,
+Sharada,
+Shavian,
+Sinhala,
+Sora_Sompeng,
+Sundanese,
+Syloti_Nagri,
+Syriac,
+Tagalog,
+Tagbanwa,
+Tai_Le,
+Tai_Tham,
+Tai_Viet,
+Takri,
+Tamil,
+Telugu,
+Thaana,
+Thai,
+Tibetan,
+Tifinagh,
+Ugaritic,
+Vai,
+Yi.
+.
+.
+.SH "CHARACTER CLASSES"
+.rs
+.sp
+  [...]       positive character class
+  [^...]      negative character class
+  [x-y]       range (can be used for hex characters)
+  [[:xxx:]]   positive POSIX named set
+  [[:^xxx:]]  negative POSIX named set
+.sp
+  alnum       alphanumeric
+  alpha       alphabetic
+  ascii       0-127
+  blank       space or tab
+  cntrl       control character
+  digit       decimal digit
+  graph       printing, excluding space
+  lower       lower case letter
+  print       printing, including space
+  punct       printing, excluding alphanumeric
+  space       white space
+  upper       upper case letter
+  word        same as \ew
+  xdigit      hexadecimal digit
+.sp
+In PCRE, POSIX character set names recognize only ASCII characters by default,
+but some of them use Unicode properties if PCRE_UCP is set. You can use
+\eQ...\eE inside a character class.
+.
+.
+.SH "QUANTIFIERS"
+.rs
+.sp
+  ?           0 or 1, greedy
+  ?+          0 or 1, possessive
+  ??          0 or 1, lazy
+  *           0 or more, greedy
+  *+          0 or more, possessive
+  *?          0 or more, lazy
+  +           1 or more, greedy
+  ++          1 or more, possessive
+  +?          1 or more, lazy
+  {n}         exactly n
+  {n,m}       at least n, no more than m, greedy
+  {n,m}+      at least n, no more than m, possessive
+  {n,m}?      at least n, no more than m, lazy
+  {n,}        n or more, greedy
+  {n,}+       n or more, possessive
+  {n,}?       n or more, lazy
+.
+.
+.SH "ANCHORS AND SIMPLE ASSERTIONS"
+.rs
+.sp
+  \eb          word boundary
+  \eB          not a word boundary
+  ^           start of subject
+               also after internal newline in multiline mode
+  \eA          start of subject
+  $           end of subject
+               also before newline at end of subject
+               also before internal newline in multiline mode
+  \eZ          end of subject
+               also before newline at end of subject
+  \ez          end of subject
+  \eG          first matching position in subject
+.
+.
+.SH "MATCH POINT RESET"
+.rs
+.sp
+  \eK          reset start of match
+.sp
+\eK is honoured in positive assertions, but ignored in negative ones.
+.
+.
+.SH "ALTERNATION"
+.rs
+.sp
+  expr|expr|expr...
+.
+.
+.SH "CAPTURING"
+.rs
+.sp
+  (...)           capturing group
+  (?<name>...)    named capturing group (Perl)
+  (?'name'...)    named capturing group (Perl)
+  (?P<name>...)   named capturing group (Python)
+  (?:...)         non-capturing group
+  (?|...)         non-capturing group; reset group numbers for
+                   capturing groups in each alternative
+.
+.
+.SH "ATOMIC GROUPS"
+.rs
+.sp
+  (?>...)         atomic, non-capturing group
+.
+.
+.
+.
+.SH "COMMENT"
+.rs
+.sp
+  (?#....)        comment (not nestable)
+.
+.
+.SH "OPTION SETTING"
+.rs
+.sp
+  (?i)            caseless
+  (?J)            allow duplicate names
+  (?m)            multiline
+  (?s)            single line (dotall)
+  (?U)            default ungreedy (lazy)
+  (?x)            extended (ignore white space)
+  (?-...)         unset option(s)
+.sp
+The following are recognized only at the very start of a pattern or after one
+of the newline or \eR options with similar syntax. More than one of them may
+appear.
+.sp
+  (*LIMIT_MATCH=d) set the match limit to d (decimal number)
+  (*LIMIT_RECURSION=d) set the recursion limit to d (decimal number)
+  (*NO_AUTO_POSSESS) no auto-possessification (PCRE_NO_AUTO_POSSESS)
+  (*NO_START_OPT) no start-match optimization (PCRE_NO_START_OPTIMIZE)
+  (*UTF8)         set UTF-8 mode: 8-bit library (PCRE_UTF8)
+  (*UTF16)        set UTF-16 mode: 16-bit library (PCRE_UTF16)
+  (*UTF32)        set UTF-32 mode: 32-bit library (PCRE_UTF32)
+  (*UTF)          set appropriate UTF mode for the library in use
+  (*UCP)          set PCRE_UCP (use Unicode properties for \ed etc)
+.sp
+Note that LIMIT_MATCH and LIMIT_RECURSION can only reduce the value of the
+limits set by the caller of pcre_exec(), not increase them.
+.
+.
+.SH "NEWLINE CONVENTION"
+.rs
+.sp
+These are recognized only at the very start of the pattern or after option
+settings with a similar syntax.
+.sp
+  (*CR)           carriage return only
+  (*LF)           linefeed only
+  (*CRLF)         carriage return followed by linefeed
+  (*ANYCRLF)      all three of the above
+  (*ANY)          any Unicode newline sequence
+.
+.
+.SH "WHAT \eR MATCHES"
+.rs
+.sp
+These are recognized only at the very start of the pattern or after option
+setting with a similar syntax.
+.sp
+  (*BSR_ANYCRLF)  CR, LF, or CRLF
+  (*BSR_UNICODE)  any Unicode newline sequence
+.
+.
+.SH "LOOKAHEAD AND LOOKBEHIND ASSERTIONS"
+.rs
+.sp
+  (?=...)         positive look ahead
+  (?!...)         negative look ahead
+  (?<=...)        positive look behind
+  (?<!...)        negative look behind
+.sp
+Each top-level branch of a look behind must be of a fixed length.
+.
+.
+.SH "BACKREFERENCES"
+.rs
+.sp
+  \en              reference by number (can be ambiguous)
+  \egn             reference by number
+  \eg{n}           reference by number
+  \eg{-n}          relative reference by number
+  \ek<name>        reference by name (Perl)
+  \ek'name'        reference by name (Perl)
+  \eg{name}        reference by name (Perl)
+  \ek{name}        reference by name (.NET)
+  (?P=name)       reference by name (Python)
+.
+.
+.SH "SUBROUTINE REFERENCES (POSSIBLY RECURSIVE)"
+.rs
+.sp
+  (?R)            recurse whole pattern
+  (?n)            call subpattern by absolute number
+  (?+n)           call subpattern by relative number
+  (?-n)           call subpattern by relative number
+  (?&name)        call subpattern by name (Perl)
+  (?P>name)       call subpattern by name (Python)
+  \eg<name>        call subpattern by name (Oniguruma)
+  \eg'name'        call subpattern by name (Oniguruma)
+  \eg<n>           call subpattern by absolute number (Oniguruma)
+  \eg'n'           call subpattern by absolute number (Oniguruma)
+  \eg<+n>          call subpattern by relative number (PCRE extension)
+  \eg'+n'          call subpattern by relative number (PCRE extension)
+  \eg<-n>          call subpattern by relative number (PCRE extension)
+  \eg'-n'          call subpattern by relative number (PCRE extension)
+.
+.
+.SH "CONDITIONAL PATTERNS"
+.rs
+.sp
+  (?(condition)yes-pattern)
+  (?(condition)yes-pattern|no-pattern)
+.sp
+  (?(n)...        absolute reference condition
+  (?(+n)...       relative reference condition
+  (?(-n)...       relative reference condition
+  (?(<name>)...   named reference condition (Perl)
+  (?('name')...   named reference condition (Perl)
+  (?(name)...     named reference condition (PCRE)
+  (?(R)...        overall recursion condition
+  (?(Rn)...       specific group recursion condition
+  (?(R&name)...   specific recursion condition
+  (?(DEFINE)...   define subpattern for reference
+  (?(assert)...   assertion condition
+.
+.
+.SH "BACKTRACKING CONTROL"
+.rs
+.sp
+The following act immediately they are reached:
+.sp
+  (*ACCEPT)       force successful match
+  (*FAIL)         force backtrack; synonym (*F)
+  (*MARK:NAME)    set name to be passed back; synonym (*:NAME)
+.sp
+The following act only when a subsequent match failure causes a backtrack to
+reach them. They all force a match failure, but they differ in what happens
+afterwards. Those that advance the start-of-match point do so only if the
+pattern is not anchored.
+.sp
+  (*COMMIT)       overall failure, no advance of starting point
+  (*PRUNE)        advance to next starting character
+  (*PRUNE:NAME)   equivalent to (*MARK:NAME)(*PRUNE)
+  (*SKIP)         advance to current matching position
+  (*SKIP:NAME)    advance to position corresponding to an earlier
+                  (*MARK:NAME); if not found, the (*SKIP) is ignored
+  (*THEN)         local failure, backtrack to next alternation
+  (*THEN:NAME)    equivalent to (*MARK:NAME)(*THEN)
+.
+.
+.SH "CALLOUTS"
+.rs
+.sp
+  (?C)      callout
+  (?Cn)     callout with data n
+.
+.
+.SH "SEE ALSO"
+.rs
+.sp
+\fBpcrepattern\fP(3), \fBpcreapi\fP(3), \fBpcrecallout\fP(3),
+\fBpcrematching\fP(3), \fBpcre\fP(3).
+.
+.
+.SH AUTHOR
+.rs
+.sp
+.nf
+Philip Hazel
+University Computing Service
+Cambridge CB2 3QH, England.
+.fi
+.
+.
+.SH REVISION
+.rs
+.sp
+.nf
+Last updated: 08 January 2014
+Copyright (c) 1997-2014 University of Cambridge.
+.fi
diff --git a/libs/Pcre16/docs/doc/pcretest.1 b/libs/Pcre16/docs/doc/pcretest.1
new file mode 100644
index 0000000000..92640da8e1
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcretest.1
@@ -0,0 +1,1156 @@
+.TH PCRETEST 1 "09 February 2014" "PCRE 8.35"
+.SH NAME
+pcretest - a program for testing Perl-compatible regular expressions.
+.SH SYNOPSIS
+.rs
+.sp
+.B pcretest "[options] [input file [output file]]"
+.sp
+\fBpcretest\fP was written as a test program for the PCRE regular expression
+library itself, but it can also be used for experimenting with regular
+expressions. This document describes the features of the test program; for
+details of the regular expressions themselves, see the
+.\" HREF
+\fBpcrepattern\fP
+.\"
+documentation. For details of the PCRE library function calls and their
+options, see the
+.\" HREF
+\fBpcreapi\fP
+.\"
+,
+.\" HREF
+\fBpcre16\fP
+and
+.\" HREF
+\fBpcre32\fP
+.\"
+documentation.
+.P
+The input for \fBpcretest\fP is a sequence of regular expression patterns and
+strings to be matched, as described below. The output shows the result of each
+match. Options on the command line and the patterns control PCRE options and
+exactly what is output.
+.P
+As PCRE has evolved, it has acquired many different features, and as a result,
+\fBpcretest\fP now has rather a lot of obscure options for testing every
+possible feature. Some of these options are specifically designed for use in
+conjunction with the test script and data files that are distributed as part of
+PCRE, and are unlikely to be of use otherwise. They are all documented here,
+but without much justification.
+.
+.
+.SH "INPUT DATA FORMAT"
+.rs
+.sp
+Input to \fBpcretest\fP is processed line by line, either by calling the C
+library's \fBfgets()\fP function, or via the \fBlibreadline\fP library (see
+below). In Unix-like environments, \fBfgets()\fP treats any bytes other than
+newline as data characters. However, in some Windows environments character 26
+(hex 1A) causes an immediate end of file, and no further data is read. For
+maximum portability, therefore, it is safest to use only ASCII characters in
+\fBpcretest\fP input files.
+.
+.
+.SH "PCRE's 8-BIT, 16-BIT AND 32-BIT LIBRARIES"
+.rs
+.sp
+From release 8.30, two separate PCRE libraries can be built. The original one
+supports 8-bit character strings, whereas the newer 16-bit library supports
+character strings encoded in 16-bit units. From release 8.32, a third library
+can be built, supporting character strings encoded in 32-bit units. The
+\fBpcretest\fP program can be used to test all three libraries. However, it is
+itself still an 8-bit program, reading 8-bit input and writing 8-bit output.
+When testing the 16-bit or 32-bit library, the patterns and data strings are
+converted to 16- or 32-bit format before being passed to the PCRE library
+functions. Results are converted to 8-bit for output.
+.P
+References to functions and structures of the form \fBpcre[16|32]_xx\fP below
+mean "\fBpcre_xx\fP when using the 8-bit library, \fBpcre16_xx\fP when using
+the 16-bit library, or \fBpcre32_xx\fP when using the 32-bit library".
+.
+.
+.SH "COMMAND LINE OPTIONS"
+.rs
+.TP 10
+\fB-8\fP
+If both the 8-bit library has been built, this option causes the 8-bit library
+to be used (which is the default); if the 8-bit library has not been built,
+this option causes an error.
+.TP 10
+\fB-16\fP
+If both the 8-bit or the 32-bit, and the 16-bit libraries have been built, this
+option causes the 16-bit library to be used. If only the 16-bit library has been
+built, this is the default (so has no effect). If only the 8-bit or the 32-bit
+library has been built, this option causes an error.
+.TP 10
+\fB-32\fP
+If both the 8-bit or the 16-bit, and the 32-bit libraries have been built, this
+option causes the 32-bit library to be used. If only the 32-bit library has been
+built, this is the default (so has no effect). If only the 8-bit or the 16-bit
+library has been built, this option causes an error.
+.TP 10
+\fB-b\fP
+Behave as if each pattern has the \fB/B\fP (show byte code) modifier; the
+internal form is output after compilation.
+.TP 10
+\fB-C\fP
+Output the version number of the PCRE library, and all available information
+about the optional features that are included, and then exit with zero exit
+code. All other options are ignored.
+.TP 10
+\fB-C\fP \fIoption\fP
+Output information about a specific build-time option, then exit. This
+functionality is intended for use in scripts such as \fBRunTest\fP. The
+following options output the value and set the exit code as indicated:
+.sp
+  ebcdic-nl  the code for LF (= NL) in an EBCDIC environment:
+               0x15 or 0x25
+               0 if used in an ASCII environment
+               exit code is always 0
+  linksize   the configured internal link size (2, 3, or 4)
+               exit code is set to the link size
+  newline    the default newline setting:
+               CR, LF, CRLF, ANYCRLF, or ANY
+               exit code is always 0
+  bsr        the default setting for what \eR matches:
+               ANYCRLF or ANY
+               exit code is always 0
+.sp
+The following options output 1 for true or 0 for false, and set the exit code
+to the same value:
+.sp
+  ebcdic     compiled for an EBCDIC environment
+  jit        just-in-time support is available
+  pcre16     the 16-bit library was built
+  pcre32     the 32-bit library was built
+  pcre8      the 8-bit library was built
+  ucp        Unicode property support is available
+  utf        UTF-8 and/or UTF-16 and/or UTF-32 support
+               is available
+.sp
+If an unknown option is given, an error message is output; the exit code is 0.
+.TP 10
+\fB-d\fP
+Behave as if each pattern has the \fB/D\fP (debug) modifier; the internal
+form and information about the compiled pattern is output after compilation;
+\fB-d\fP is equivalent to \fB-b -i\fP.
+.TP 10
+\fB-dfa\fP
+Behave as if each data line contains the \eD escape sequence; this causes the
+alternative matching function, \fBpcre[16|32]_dfa_exec()\fP, to be used instead
+of the standard \fBpcre[16|32]_exec()\fP function (more detail is given below).
+.TP 10
+\fB-help\fP
+Output a brief summary these options and then exit.
+.TP 10
+\fB-i\fP
+Behave as if each pattern has the \fB/I\fP modifier; information about the
+compiled pattern is given after compilation.
+.TP 10
+\fB-M\fP
+Behave as if each data line contains the \eM escape sequence; this causes
+PCRE to discover the minimum MATCH_LIMIT and MATCH_LIMIT_RECURSION settings by
+calling \fBpcre[16|32]_exec()\fP repeatedly with different limits.
+.TP 10
+\fB-m\fP
+Output the size of each compiled pattern after it has been compiled. This is
+equivalent to adding \fB/M\fP to each regular expression. The size is given in
+bytes for both libraries.
+.TP 10
+\fB-O\fP
+Behave as if each pattern has the \fB/O\fP modifier, that is disable
+auto-possessification for all patterns.
+.TP 10
+\fB-o\fP \fIosize\fP
+Set the number of elements in the output vector that is used when calling
+\fBpcre[16|32]_exec()\fP or \fBpcre[16|32]_dfa_exec()\fP to be \fIosize\fP. The
+default value is 45, which is enough for 14 capturing subexpressions for
+\fBpcre[16|32]_exec()\fP or 22 different matches for
+\fBpcre[16|32]_dfa_exec()\fP.
+The vector size can be changed for individual matching calls by including \eO
+in the data line (see below).
+.TP 10
+\fB-p\fP
+Behave as if each pattern has the \fB/P\fP modifier; the POSIX wrapper API is
+used to call PCRE. None of the other options has any effect when \fB-p\fP is
+set. This option can be used only with the 8-bit library.
+.TP 10
+\fB-q\fP
+Do not output the version number of \fBpcretest\fP at the start of execution.
+.TP 10
+\fB-S\fP \fIsize\fP
+On Unix-like systems, set the size of the run-time stack to \fIsize\fP
+megabytes.
+.TP 10
+\fB-s\fP or \fB-s+\fP
+Behave as if each pattern has the \fB/S\fP modifier; in other words, force each
+pattern to be studied. If \fB-s+\fP is used, all the JIT compile options are
+passed to \fBpcre[16|32]_study()\fP, causing just-in-time optimization to be set
+up if it is available, for both full and partial matching. Specific JIT compile
+options can be selected by following \fB-s+\fP with a digit in the range 1 to
+7, which selects the JIT compile modes as follows:
+.sp
+  1  normal match only
+  2  soft partial match only
+  3  normal match and soft partial match
+  4  hard partial match only
+  6  soft and hard partial match
+  7  all three modes (default)
+.sp
+If \fB-s++\fP is used instead of \fB-s+\fP (with or without a following digit),
+the text "(JIT)" is added to the first output line after a match or no match
+when JIT-compiled code was actually used.
+.sp
+Note that there are pattern options that can override \fB-s\fP, either
+specifying no studying at all, or suppressing JIT compilation.
+.sp
+If the \fB/I\fP or \fB/D\fP option is present on a pattern (requesting output
+about the compiled pattern), information about the result of studying is not
+included when studying is caused only by \fB-s\fP and neither \fB-i\fP nor
+\fB-d\fP is present on the command line. This behaviour means that the output
+from tests that are run with and without \fB-s\fP should be identical, except
+when options that output information about the actual running of a match are
+set.
+.sp
+The \fB-M\fP, \fB-t\fP, and \fB-tm\fP options, which give information about
+resources used, are likely to produce different output with and without
+\fB-s\fP. Output may also differ if the \fB/C\fP option is present on an
+individual pattern. This uses callouts to trace the the matching process, and
+this may be different between studied and non-studied patterns. If the pattern
+contains (*MARK) items there may also be differences, for the same reason. The
+\fB-s\fP command line option can be overridden for specific patterns that
+should never be studied (see the \fB/S\fP pattern modifier below).
+.TP 10
+\fB-t\fP
+Run each compile, study, and match many times with a timer, and output the
+resulting times per compile, study, or match (in milliseconds). Do not set
+\fB-m\fP with \fB-t\fP, because you will then get the size output a zillion
+times, and the timing will be distorted. You can control the number of
+iterations that are used for timing by following \fB-t\fP with a number (as a
+separate item on the command line). For example, "-t 1000" iterates 1000 times.
+The default is to iterate 500000 times.
+.TP 10
+\fB-tm\fP
+This is like \fB-t\fP except that it times only the matching phase, not the
+compile or study phases.
+.TP 10
+\fB-T\fP \fB-TM\fP
+These behave like \fB-t\fP and \fB-tm\fP, but in addition, at the end of a run,
+the total times for all compiles, studies, and matches are output.
+.
+.
+.SH DESCRIPTION
+.rs
+.sp
+If \fBpcretest\fP is given two filename arguments, it reads from the first and
+writes to the second. If it is given only one filename argument, it reads from
+that file and writes to stdout. Otherwise, it reads from stdin and writes to
+stdout, and prompts for each line of input, using "re>" to prompt for regular
+expressions, and "data>" to prompt for data lines.
+.P
+When \fBpcretest\fP is built, a configuration option can specify that it should
+be linked with the \fBlibreadline\fP library. When this is done, if the input
+is from a terminal, it is read using the \fBreadline()\fP function. This
+provides line-editing and history facilities. The output from the \fB-help\fP
+option states whether or not \fBreadline()\fP will be used.
+.P
+The program handles any number of sets of input on a single input file. Each
+set starts with a regular expression, and continues with any number of data
+lines to be matched against that pattern.
+.P
+Each data line is matched separately and independently. If you want to do
+multi-line matches, you have to use the \en escape sequence (or \er or \er\en,
+etc., depending on the newline setting) in a single line of input to encode the
+newline sequences. There is no limit on the length of data lines; the input
+buffer is automatically extended if it is too small.
+.P
+An empty line signals the end of the data lines, at which point a new regular
+expression is read. The regular expressions are given enclosed in any
+non-alphanumeric delimiters other than backslash, for example:
+.sp
+  /(a|bc)x+yz/
+.sp
+White space before the initial delimiter is ignored. A regular expression may
+be continued over several input lines, in which case the newline characters are
+included within it. It is possible to include the delimiter within the pattern
+by escaping it, for example
+.sp
+  /abc\e/def/
+.sp
+If you do so, the escape and the delimiter form part of the pattern, but since
+delimiters are always non-alphanumeric, this does not affect its interpretation.
+If the terminating delimiter is immediately followed by a backslash, for
+example,
+.sp
+  /abc/\e
+.sp
+then a backslash is added to the end of the pattern. This is done to provide a
+way of testing the error condition that arises if a pattern finishes with a
+backslash, because
+.sp
+  /abc\e/
+.sp
+is interpreted as the first line of a pattern that starts with "abc/", causing
+pcretest to read the next line as a continuation of the regular expression.
+.
+.
+.SH "PATTERN MODIFIERS"
+.rs
+.sp
+A pattern may be followed by any number of modifiers, which are mostly single
+characters, though some of these can be qualified by further characters.
+Following Perl usage, these are referred to below as, for example, "the
+\fB/i\fP modifier", even though the delimiter of the pattern need not always be
+a slash, and no slash is used when writing modifiers. White space may appear
+between the final pattern delimiter and the first modifier, and between the
+modifiers themselves. For reference, here is a complete list of modifiers. They
+fall into several groups that are described in detail in the following
+sections.
+.sp
+  \fB/8\fP              set UTF mode
+  \fB/9\fP              set PCRE_NEVER_UTF (locks out UTF mode)
+  \fB/?\fP              disable UTF validity check
+  \fB/+\fP              show remainder of subject after match
+  \fB/=\fP              show all captures (not just those that are set)
+.sp
+  \fB/A\fP              set PCRE_ANCHORED
+  \fB/B\fP              show compiled code
+  \fB/C\fP              set PCRE_AUTO_CALLOUT
+  \fB/D\fP              same as \fB/B\fP plus \fB/I\fP
+  \fB/E\fP              set PCRE_DOLLAR_ENDONLY
+  \fB/F\fP              flip byte order in compiled pattern
+  \fB/f\fP              set PCRE_FIRSTLINE
+  \fB/G\fP              find all matches (shorten string)
+  \fB/g\fP              find all matches (use startoffset)
+  \fB/I\fP              show information about pattern
+  \fB/i\fP              set PCRE_CASELESS
+  \fB/J\fP              set PCRE_DUPNAMES
+  \fB/K\fP              show backtracking control names
+  \fB/L\fP              set locale
+  \fB/M\fP              show compiled memory size
+  \fB/m\fP              set PCRE_MULTILINE
+  \fB/N\fP              set PCRE_NO_AUTO_CAPTURE
+  \fB/O\fP              set PCRE_NO_AUTO_POSSESS
+  \fB/P\fP              use the POSIX wrapper
+  \fB/Q\fP              test external stack check function
+  \fB/S\fP              study the pattern after compilation
+  \fB/s\fP              set PCRE_DOTALL
+  \fB/T\fP              select character tables
+  \fB/U\fP              set PCRE_UNGREEDY
+  \fB/W\fP              set PCRE_UCP
+  \fB/X\fP              set PCRE_EXTRA
+  \fB/x\fP              set PCRE_EXTENDED
+  \fB/Y\fP              set PCRE_NO_START_OPTIMIZE
+  \fB/Z\fP              don't show lengths in \fB/B\fP output
+.sp
+  \fB/<any>\fP          set PCRE_NEWLINE_ANY
+  \fB/<anycrlf>\fP      set PCRE_NEWLINE_ANYCRLF
+  \fB/<cr>\fP           set PCRE_NEWLINE_CR
+  \fB/<crlf>\fP         set PCRE_NEWLINE_CRLF
+  \fB/<lf>\fP           set PCRE_NEWLINE_LF
+  \fB/<bsr_anycrlf>\fP  set PCRE_BSR_ANYCRLF
+  \fB/<bsr_unicode>\fP  set PCRE_BSR_UNICODE
+  \fB/<JS>\fP           set PCRE_JAVASCRIPT_COMPAT
+.sp
+.
+.
+.SS "Perl-compatible modifiers"
+.rs
+.sp
+The \fB/i\fP, \fB/m\fP, \fB/s\fP, and \fB/x\fP modifiers set the PCRE_CASELESS,
+PCRE_MULTILINE, PCRE_DOTALL, or PCRE_EXTENDED options, respectively, when
+\fBpcre[16|32]_compile()\fP is called. These four modifier letters have the same
+effect as they do in Perl. For example:
+.sp
+  /caseless/i
+.sp
+.
+.
+.SS "Modifiers for other PCRE options"
+.rs
+.sp
+The following table shows additional modifiers for setting PCRE compile-time
+options that do not correspond to anything in Perl:
+.sp
+  \fB/8\fP              PCRE_UTF8           ) when using the 8-bit
+  \fB/?\fP              PCRE_NO_UTF8_CHECK  )   library
+.sp
+  \fB/8\fP              PCRE_UTF16          ) when using the 16-bit
+  \fB/?\fP              PCRE_NO_UTF16_CHECK )   library
+.sp
+  \fB/8\fP              PCRE_UTF32          ) when using the 32-bit
+  \fB/?\fP              PCRE_NO_UTF32_CHECK )   library
+.sp
+  \fB/9\fP              PCRE_NEVER_UTF
+  \fB/A\fP              PCRE_ANCHORED
+  \fB/C\fP              PCRE_AUTO_CALLOUT
+  \fB/E\fP              PCRE_DOLLAR_ENDONLY
+  \fB/f\fP              PCRE_FIRSTLINE
+  \fB/J\fP              PCRE_DUPNAMES
+  \fB/N\fP              PCRE_NO_AUTO_CAPTURE
+  \fB/O\fP              PCRE_NO_AUTO_POSSESS
+  \fB/U\fP              PCRE_UNGREEDY
+  \fB/W\fP              PCRE_UCP
+  \fB/X\fP              PCRE_EXTRA
+  \fB/Y\fP              PCRE_NO_START_OPTIMIZE
+  \fB/<any>\fP          PCRE_NEWLINE_ANY
+  \fB/<anycrlf>\fP      PCRE_NEWLINE_ANYCRLF
+  \fB/<cr>\fP           PCRE_NEWLINE_CR
+  \fB/<crlf>\fP         PCRE_NEWLINE_CRLF
+  \fB/<lf>\fP           PCRE_NEWLINE_LF
+  \fB/<bsr_anycrlf>\fP  PCRE_BSR_ANYCRLF
+  \fB/<bsr_unicode>\fP  PCRE_BSR_UNICODE
+  \fB/<JS>\fP           PCRE_JAVASCRIPT_COMPAT
+.sp
+The modifiers that are enclosed in angle brackets are literal strings as shown,
+including the angle brackets, but the letters within can be in either case.
+This example sets multiline matching with CRLF as the line ending sequence:
+.sp
+  /^abc/m<CRLF>
+.sp
+As well as turning on the PCRE_UTF8/16/32 option, the \fB/8\fP modifier causes
+all non-printing characters in output strings to be printed using the
+\ex{hh...} notation. Otherwise, those less than 0x100 are output in hex without
+the curly brackets.
+.P
+Full details of the PCRE options are given in the
+.\" HREF
+\fBpcreapi\fP
+.\"
+documentation.
+.
+.
+.SS "Finding all matches in a string"
+.rs
+.sp
+Searching for all possible matches within each subject string can be requested
+by the \fB/g\fP or \fB/G\fP modifier. After finding a match, PCRE is called
+again to search the remainder of the subject string. The difference between
+\fB/g\fP and \fB/G\fP is that the former uses the \fIstartoffset\fP argument to
+\fBpcre[16|32]_exec()\fP to start searching at a new point within the entire
+string (which is in effect what Perl does), whereas the latter passes over a
+shortened substring. This makes a difference to the matching process if the
+pattern begins with a lookbehind assertion (including \eb or \eB).
+.P
+If any call to \fBpcre[16|32]_exec()\fP in a \fB/g\fP or \fB/G\fP sequence matches
+an empty string, the next call is done with the PCRE_NOTEMPTY_ATSTART and
+PCRE_ANCHORED flags set in order to search for another, non-empty, match at the
+same point. If this second match fails, the start offset is advanced, and the
+normal match is retried. This imitates the way Perl handles such cases when
+using the \fB/g\fP modifier or the \fBsplit()\fP function. Normally, the start
+offset is advanced by one character, but if the newline convention recognizes
+CRLF as a newline, and the current character is CR followed by LF, an advance
+of two is used.
+.
+.
+.SS "Other modifiers"
+.rs
+.sp
+There are yet more modifiers for controlling the way \fBpcretest\fP
+operates.
+.P
+The \fB/+\fP modifier requests that as well as outputting the substring that
+matched the entire pattern, \fBpcretest\fP should in addition output the
+remainder of the subject string. This is useful for tests where the subject
+contains multiple copies of the same substring. If the \fB+\fP modifier appears
+twice, the same action is taken for captured substrings. In each case the
+remainder is output on the following line with a plus character following the
+capture number. Note that this modifier must not immediately follow the /S
+modifier because /S+ and /S++ have other meanings.
+.P
+The \fB/=\fP modifier requests that the values of all potential captured
+parentheses be output after a match. By default, only those up to the highest
+one actually used in the match are output (corresponding to the return code
+from \fBpcre[16|32]_exec()\fP). Values in the offsets vector corresponding to
+higher numbers should be set to -1, and these are output as "<unset>". This
+modifier gives a way of checking that this is happening.
+.P
+The \fB/B\fP modifier is a debugging feature. It requests that \fBpcretest\fP
+output a representation of the compiled code after compilation. Normally this
+information contains length and offset values; however, if \fB/Z\fP is also
+present, this data is replaced by spaces. This is a special feature for use in
+the automatic test scripts; it ensures that the same output is generated for
+different internal link sizes.
+.P
+The \fB/D\fP modifier is a PCRE debugging feature, and is equivalent to
+\fB/BI\fP, that is, both the \fB/B\fP and the \fB/I\fP modifiers.
+.P
+The \fB/F\fP modifier causes \fBpcretest\fP to flip the byte order of the
+2-byte and 4-byte fields in the compiled pattern. This facility is for testing
+the feature in PCRE that allows it to execute patterns that were compiled on a
+host with a different endianness. This feature is not available when the POSIX
+interface to PCRE is being used, that is, when the \fB/P\fP pattern modifier is
+specified. See also the section about saving and reloading compiled patterns
+below.
+.P
+The \fB/I\fP modifier requests that \fBpcretest\fP output information about the
+compiled pattern (whether it is anchored, has a fixed first character, and
+so on). It does this by calling \fBpcre[16|32]_fullinfo()\fP after compiling a
+pattern. If the pattern is studied, the results of that are also output. In
+this output, the word "char" means a non-UTF character, that is, the value of a
+single data item (8-bit, 16-bit, or 32-bit, depending on the library that is
+being tested).
+.P
+The \fB/K\fP modifier requests \fBpcretest\fP to show names from backtracking
+control verbs that are returned from calls to \fBpcre[16|32]_exec()\fP. It causes
+\fBpcretest\fP to create a \fBpcre[16|32]_extra\fP block if one has not already
+been created by a call to \fBpcre[16|32]_study()\fP, and to set the
+PCRE_EXTRA_MARK flag and the \fBmark\fP field within it, every time that
+\fBpcre[16|32]_exec()\fP is called. If the variable that the \fBmark\fP field
+points to is non-NULL for a match, non-match, or partial match, \fBpcretest\fP
+prints the string to which it points. For a match, this is shown on a line by
+itself, tagged with "MK:". For a non-match it is added to the message.
+.P
+The \fB/L\fP modifier must be followed directly by the name of a locale, for
+example,
+.sp
+  /pattern/Lfr_FR
+.sp
+For this reason, it must be the last modifier. The given locale is set,
+\fBpcre[16|32]_maketables()\fP is called to build a set of character tables for
+the locale, and this is then passed to \fBpcre[16|32]_compile()\fP when compiling
+the regular expression. Without an \fB/L\fP (or \fB/T\fP) modifier, NULL is
+passed as the tables pointer; that is, \fB/L\fP applies only to the expression
+on which it appears.
+.P
+The \fB/M\fP modifier causes the size in bytes of the memory block used to hold
+the compiled pattern to be output. This does not include the size of the
+\fBpcre[16|32]\fP block; it is just the actual compiled data. If the pattern is
+successfully studied with the PCRE_STUDY_JIT_COMPILE option, the size of the
+JIT compiled code is also output.
+.P
+The \fB/Q\fP modifier is used to test the use of \fBpcre_stack_guard\fP. It
+must be followed by '0' or '1', specifying the return code to be given from an
+external function that is passed to PCRE and used for stack checking during
+compilation (see the
+.\" HREF
+\fBpcreapi\fP
+.\"
+documentation for details).
+.P
+The \fB/S\fP modifier causes \fBpcre[16|32]_study()\fP to be called after the
+expression has been compiled, and the results used when the expression is
+matched. There are a number of qualifying characters that may follow \fB/S\fP.
+They may appear in any order.
+.P
+If \fB/S\fP is followed by an exclamation mark, \fBpcre[16|32]_study()\fP is
+called with the PCRE_STUDY_EXTRA_NEEDED option, causing it always to return a
+\fBpcre_extra\fP block, even when studying discovers no useful information.
+.P
+If \fB/S\fP is followed by a second S character, it suppresses studying, even
+if it was requested externally by the \fB-s\fP command line option. This makes
+it possible to specify that certain patterns are always studied, and others are
+never studied, independently of \fB-s\fP. This feature is used in the test
+files in a few cases where the output is different when the pattern is studied.
+.P
+If the \fB/S\fP modifier is followed by a + character, the call to
+\fBpcre[16|32]_study()\fP is made with all the JIT study options, requesting
+just-in-time optimization support if it is available, for both normal and
+partial matching. If you want to restrict the JIT compiling modes, you can
+follow \fB/S+\fP with a digit in the range 1 to 7:
+.sp
+  1  normal match only
+  2  soft partial match only
+  3  normal match and soft partial match
+  4  hard partial match only
+  6  soft and hard partial match
+  7  all three modes (default)
+.sp
+If \fB/S++\fP is used instead of \fB/S+\fP (with or without a following digit),
+the text "(JIT)" is added to the first output line after a match or no match
+when JIT-compiled code was actually used.
+.P
+Note that there is also an independent \fB/+\fP modifier; it must not be given
+immediately after \fB/S\fP or \fB/S+\fP because this will be misinterpreted.
+.P
+If JIT studying is successful, the compiled JIT code will automatically be used
+when \fBpcre[16|32]_exec()\fP is run, except when incompatible run-time options
+are specified. For more details, see the
+.\" HREF
+\fBpcrejit\fP
+.\"
+documentation. See also the \fB\eJ\fP escape sequence below for a way of
+setting the size of the JIT stack.
+.P
+Finally, if \fB/S\fP is followed by a minus character, JIT compilation is
+suppressed, even if it was requested externally by the \fB-s\fP command line
+option. This makes it possible to specify that JIT is never to be used for
+certain patterns.
+.P
+The \fB/T\fP modifier must be followed by a single digit. It causes a specific
+set of built-in character tables to be passed to \fBpcre[16|32]_compile()\fP. It
+is used in the standard PCRE tests to check behaviour with different character
+tables. The digit specifies the tables as follows:
+.sp
+  0   the default ASCII tables, as distributed in
+        pcre_chartables.c.dist
+  1   a set of tables defining ISO 8859 characters
+.sp
+In table 1, some characters whose codes are greater than 128 are identified as
+letters, digits, spaces, etc.
+.
+.
+.SS "Using the POSIX wrapper API"
+.rs
+.sp
+The \fB/P\fP modifier causes \fBpcretest\fP to call PCRE via the POSIX wrapper
+API rather than its native API. This supports only the 8-bit library. When
+\fB/P\fP is set, the following modifiers set options for the \fBregcomp()\fP
+function:
+.sp
+  /i    REG_ICASE
+  /m    REG_NEWLINE
+  /N    REG_NOSUB
+  /s    REG_DOTALL     )
+  /U    REG_UNGREEDY   ) These options are not part of
+  /W    REG_UCP        )   the POSIX standard
+  /8    REG_UTF8       )
+.sp
+The \fB/+\fP modifier works as described above. All other modifiers are
+ignored.
+.
+.
+.SS "Locking out certain modifiers"
+.rs
+.sp
+PCRE can be compiled with or without support for certain features such as
+UTF-8/16/32 or Unicode properties. Accordingly, the standard tests are split up
+into a number of different files that are selected for running depending on
+which features are available. When updating the tests, it is all too easy to
+put a new test into the wrong file by mistake; for example, to put a test that
+requires UTF support into a file that is used when it is not available. To help
+detect such mistakes as early as possible, there is a facility for locking out
+specific modifiers. If an input line for \fBpcretest\fP starts with the string
+"< forbid " the following sequence of characters is taken as a list of
+forbidden modifiers. For example, in the test files that must not use UTF or
+Unicode property support, this line appears:
+.sp
+  < forbid 8W
+.sp
+This locks out the /8 and /W modifiers. An immediate error is given if they are
+subsequently encountered. If the character string contains < but not >, all the
+multi-character modifiers that begin with < are locked out. Otherwise, such
+modifiers must be explicitly listed, for example:
+.sp
+  < forbid <JS><cr>
+.sp
+There must be a single space between < and "forbid" for this feature to be
+recognised. If there is not, the line is interpreted either as a request to
+re-load a pre-compiled pattern (see "SAVING AND RELOADING COMPILED PATTERNS"
+below) or, if there is a another < character, as a pattern that uses < as its
+delimiter.
+.
+.
+.SH "DATA LINES"
+.rs
+.sp
+Before each data line is passed to \fBpcre[16|32]_exec()\fP, leading and trailing
+white space is removed, and it is then scanned for \e escapes. Some of these
+are pretty esoteric features, intended for checking out some of the more
+complicated features of PCRE. If you are just testing "ordinary" regular
+expressions, you probably don't need any of these. The following escapes are
+recognized:
+.sp
+  \ea         alarm (BEL, \ex07)
+  \eb         backspace (\ex08)
+  \ee         escape (\ex27)
+  \ef         form feed (\ex0c)
+  \en         newline (\ex0a)
+.\" JOIN
+  \eqdd       set the PCRE_MATCH_LIMIT limit to dd
+               (any number of digits)
+  \er         carriage return (\ex0d)
+  \et         tab (\ex09)
+  \ev         vertical tab (\ex0b)
+  \ennn       octal character (up to 3 octal digits); always
+               a byte unless > 255 in UTF-8 or 16-bit or 32-bit mode
+  \eo{dd...}  octal character (any number of octal digits}
+  \exhh       hexadecimal byte (up to 2 hex digits)
+  \ex{hh...}  hexadecimal character (any number of hex digits)
+.\" JOIN
+  \eA         pass the PCRE_ANCHORED option to \fBpcre[16|32]_exec()\fP
+               or \fBpcre[16|32]_dfa_exec()\fP
+.\" JOIN
+  \eB         pass the PCRE_NOTBOL option to \fBpcre[16|32]_exec()\fP
+               or \fBpcre[16|32]_dfa_exec()\fP
+.\" JOIN
+  \eCdd       call pcre[16|32]_copy_substring() for substring dd
+               after a successful match (number less than 32)
+.\" JOIN
+  \eCname     call pcre[16|32]_copy_named_substring() for substring
+               "name" after a successful match (name termin-
+               ated by next non alphanumeric character)
+.\" JOIN
+  \eC+        show the current captured substrings at callout
+               time
+  \eC-        do not supply a callout function
+.\" JOIN
+  \eC!n       return 1 instead of 0 when callout number n is
+               reached
+.\" JOIN
+  \eC!n!m     return 1 instead of 0 when callout number n is
+               reached for the nth time
+.\" JOIN
+  \eC*n       pass the number n (may be negative) as callout
+               data; this is used as the callout return value
+  \eD         use the \fBpcre[16|32]_dfa_exec()\fP match function
+  \eF         only shortest match for \fBpcre[16|32]_dfa_exec()\fP
+.\" JOIN
+  \eGdd       call pcre[16|32]_get_substring() for substring dd
+               after a successful match (number less than 32)
+.\" JOIN
+  \eGname     call pcre[16|32]_get_named_substring() for substring
+               "name" after a successful match (name termin-
+               ated by next non-alphanumeric character)
+.\" JOIN
+  \eJdd       set up a JIT stack of dd kilobytes maximum (any
+               number of digits)
+.\" JOIN
+  \eL         call pcre[16|32]_get_substringlist() after a
+               successful match
+.\" JOIN
+  \eM         discover the minimum MATCH_LIMIT and
+               MATCH_LIMIT_RECURSION settings
+.\" JOIN
+  \eN         pass the PCRE_NOTEMPTY option to \fBpcre[16|32]_exec()\fP
+               or \fBpcre[16|32]_dfa_exec()\fP; if used twice, pass the
+               PCRE_NOTEMPTY_ATSTART option
+.\" JOIN
+  \eOdd       set the size of the output vector passed to
+               \fBpcre[16|32]_exec()\fP to dd (any number of digits)
+.\" JOIN
+  \eP         pass the PCRE_PARTIAL_SOFT option to \fBpcre[16|32]_exec()\fP
+               or \fBpcre[16|32]_dfa_exec()\fP; if used twice, pass the
+               PCRE_PARTIAL_HARD option
+.\" JOIN
+  \eQdd       set the PCRE_MATCH_LIMIT_RECURSION limit to dd
+               (any number of digits)
+  \eR         pass the PCRE_DFA_RESTART option to \fBpcre[16|32]_dfa_exec()\fP
+  \eS         output details of memory get/free calls during matching
+.\" JOIN
+  \eY         pass the PCRE_NO_START_OPTIMIZE option to \fBpcre[16|32]_exec()\fP
+               or \fBpcre[16|32]_dfa_exec()\fP
+.\" JOIN
+  \eZ         pass the PCRE_NOTEOL option to \fBpcre[16|32]_exec()\fP
+               or \fBpcre[16|32]_dfa_exec()\fP
+.\" JOIN
+  \e?         pass the PCRE_NO_UTF[8|16|32]_CHECK option to
+               \fBpcre[16|32]_exec()\fP or \fBpcre[16|32]_dfa_exec()\fP
+.\" JOIN
+  \e>dd       start the match at offset dd (optional "-"; then
+               any number of digits); this sets the \fIstartoffset\fP
+               argument for \fBpcre[16|32]_exec()\fP or \fBpcre[16|32]_dfa_exec()\fP
+.\" JOIN
+  \e<cr>      pass the PCRE_NEWLINE_CR option to \fBpcre[16|32]_exec()\fP
+               or \fBpcre[16|32]_dfa_exec()\fP
+.\" JOIN
+  \e<lf>      pass the PCRE_NEWLINE_LF option to \fBpcre[16|32]_exec()\fP
+               or \fBpcre[16|32]_dfa_exec()\fP
+.\" JOIN
+  \e<crlf>    pass the PCRE_NEWLINE_CRLF option to \fBpcre[16|32]_exec()\fP
+               or \fBpcre[16|32]_dfa_exec()\fP
+.\" JOIN
+  \e<anycrlf> pass the PCRE_NEWLINE_ANYCRLF option to \fBpcre[16|32]_exec()\fP
+               or \fBpcre[16|32]_dfa_exec()\fP
+.\" JOIN
+  \e<any>     pass the PCRE_NEWLINE_ANY option to \fBpcre[16|32]_exec()\fP
+               or \fBpcre[16|32]_dfa_exec()\fP
+.sp
+The use of \ex{hh...} is not dependent on the use of the \fB/8\fP modifier on
+the pattern. It is recognized always. There may be any number of hexadecimal
+digits inside the braces; invalid values provoke error messages.
+.P
+Note that \exhh specifies one byte rather than one character in UTF-8 mode;
+this makes it possible to construct invalid UTF-8 sequences for testing
+purposes. On the other hand, \ex{hh} is interpreted as a UTF-8 character in
+UTF-8 mode, generating more than one byte if the value is greater than 127.
+When testing the 8-bit library not in UTF-8 mode, \ex{hh} generates one byte
+for values less than 256, and causes an error for greater values.
+.P
+In UTF-16 mode, all 4-digit \ex{hhhh} values are accepted. This makes it
+possible to construct invalid UTF-16 sequences for testing purposes.
+.P
+In UTF-32 mode, all 4- to 8-digit \ex{...} values are accepted. This makes it
+possible to construct invalid UTF-32 sequences for testing purposes.
+.P
+The escapes that specify line ending sequences are literal strings, exactly as
+shown. No more than one newline setting should be present in any data line.
+.P
+A backslash followed by anything else just escapes the anything else. If
+the very last character is a backslash, it is ignored. This gives a way of
+passing an empty line as data, since a real empty line terminates the data
+input.
+.P
+The \fB\eJ\fP escape provides a way of setting the maximum stack size that is
+used by the just-in-time optimization code. It is ignored if JIT optimization
+is not being used. Providing a stack that is larger than the default 32K is
+necessary only for very complicated patterns.
+.P
+If \eM is present, \fBpcretest\fP calls \fBpcre[16|32]_exec()\fP several times,
+with different values in the \fImatch_limit\fP and \fImatch_limit_recursion\fP
+fields of the \fBpcre[16|32]_extra\fP data structure, until it finds the minimum
+numbers for each parameter that allow \fBpcre[16|32]_exec()\fP to complete without
+error. Because this is testing a specific feature of the normal interpretive
+\fBpcre[16|32]_exec()\fP execution, the use of any JIT optimization that might
+have been set up by the \fB/S+\fP qualifier of \fB-s+\fP option is disabled.
+.P
+The \fImatch_limit\fP number is a measure of the amount of backtracking
+that takes place, and checking it out can be instructive. For most simple
+matches, the number is quite small, but for patterns with very large numbers of
+matching possibilities, it can become large very quickly with increasing length
+of subject string. The \fImatch_limit_recursion\fP number is a measure of how
+much stack (or, if PCRE is compiled with NO_RECURSE, how much heap) memory is
+needed to complete the match attempt.
+.P
+When \eO is used, the value specified may be higher or lower than the size set
+by the \fB-O\fP command line option (or defaulted to 45); \eO applies only to
+the call of \fBpcre[16|32]_exec()\fP for the line in which it appears.
+.P
+If the \fB/P\fP modifier was present on the pattern, causing the POSIX wrapper
+API to be used, the only option-setting sequences that have any effect are \eB,
+\eN, and \eZ, causing REG_NOTBOL, REG_NOTEMPTY, and REG_NOTEOL, respectively,
+to be passed to \fBregexec()\fP.
+.
+.
+.SH "THE ALTERNATIVE MATCHING FUNCTION"
+.rs
+.sp
+By default, \fBpcretest\fP uses the standard PCRE matching function,
+\fBpcre[16|32]_exec()\fP to match each data line. PCRE also supports an
+alternative matching function, \fBpcre[16|32]_dfa_test()\fP, which operates in a
+different way, and has some restrictions. The differences between the two
+functions are described in the
+.\" HREF
+\fBpcrematching\fP
+.\"
+documentation.
+.P
+If a data line contains the \eD escape sequence, or if the command line
+contains the \fB-dfa\fP option, the alternative matching function is used.
+This function finds all possible matches at a given point. If, however, the \eF
+escape sequence is present in the data line, it stops after the first match is
+found. This is always the shortest possible match.
+.
+.
+.SH "DEFAULT OUTPUT FROM PCRETEST"
+.rs
+.sp
+This section describes the output when the normal matching function,
+\fBpcre[16|32]_exec()\fP, is being used.
+.P
+When a match succeeds, \fBpcretest\fP outputs the list of captured substrings
+that \fBpcre[16|32]_exec()\fP returns, starting with number 0 for the string that
+matched the whole pattern. Otherwise, it outputs "No match" when the return is
+PCRE_ERROR_NOMATCH, and "Partial match:" followed by the partially matching
+substring when \fBpcre[16|32]_exec()\fP returns PCRE_ERROR_PARTIAL. (Note that
+this is the entire substring that was inspected during the partial match; it
+may include characters before the actual match start if a lookbehind assertion,
+\eK, \eb, or \eB was involved.) For any other return, \fBpcretest\fP outputs
+the PCRE negative error number and a short descriptive phrase. If the error is
+a failed UTF string check, the offset of the start of the failing character and
+the reason code are also output, provided that the size of the output vector is
+at least two. Here is an example of an interactive \fBpcretest\fP run.
+.sp
+  $ pcretest
+  PCRE version 8.13 2011-04-30
+.sp
+    re> /^abc(\ed+)/
+  data> abc123
+   0: abc123
+   1: 123
+  data> xyz
+  No match
+.sp
+Unset capturing substrings that are not followed by one that is set are not
+returned by \fBpcre[16|32]_exec()\fP, and are not shown by \fBpcretest\fP. In the
+following example, there are two capturing substrings, but when the first data
+line is matched, the second, unset substring is not shown. An "internal" unset
+substring is shown as "<unset>", as for the second data line.
+.sp
+    re> /(a)|(b)/
+  data> a
+   0: a
+   1: a
+  data> b
+   0: b
+   1: <unset>
+   2: b
+.sp
+If the strings contain any non-printing characters, they are output as \exhh
+escapes if the value is less than 256 and UTF mode is not set. Otherwise they
+are output as \ex{hh...} escapes. See below for the definition of non-printing
+characters. If the pattern has the \fB/+\fP modifier, the output for substring
+0 is followed by the the rest of the subject string, identified by "0+" like
+this:
+.sp
+    re> /cat/+
+  data> cataract
+   0: cat
+   0+ aract
+.sp
+If the pattern has the \fB/g\fP or \fB/G\fP modifier, the results of successive
+matching attempts are output in sequence, like this:
+.sp
+    re> /\eBi(\ew\ew)/g
+  data> Mississippi
+   0: iss
+   1: ss
+   0: iss
+   1: ss
+   0: ipp
+   1: pp
+.sp
+"No match" is output only if the first match attempt fails. Here is an example
+of a failure message (the offset 4 that is specified by \e>4 is past the end of
+the subject string):
+.sp
+    re> /xyz/
+  data> xyz\e>4
+  Error -24 (bad offset value)
+.P
+If any of the sequences \fB\eC\fP, \fB\eG\fP, or \fB\eL\fP are present in a
+data line that is successfully matched, the substrings extracted by the
+convenience functions are output with C, G, or L after the string number
+instead of a colon. This is in addition to the normal full list. The string
+length (that is, the return from the extraction function) is given in
+parentheses after each string for \fB\eC\fP and \fB\eG\fP.
+.P
+Note that whereas patterns can be continued over several lines (a plain ">"
+prompt is used for continuations), data lines may not. However newlines can be
+included in data by means of the \en escape (or \er, \er\en, etc., depending on
+the newline sequence setting).
+.
+.
+.
+.SH "OUTPUT FROM THE ALTERNATIVE MATCHING FUNCTION"
+.rs
+.sp
+When the alternative matching function, \fBpcre[16|32]_dfa_exec()\fP, is used (by
+means of the \eD escape sequence or the \fB-dfa\fP command line option), the
+output consists of a list of all the matches that start at the first point in
+the subject where there is at least one match. For example:
+.sp
+    re> /(tang|tangerine|tan)/
+  data> yellow tangerine\eD
+   0: tangerine
+   1: tang
+   2: tan
+.sp
+(Using the normal matching function on this data finds only "tang".) The
+longest matching string is always given first (and numbered zero). After a
+PCRE_ERROR_PARTIAL return, the output is "Partial match:", followed by the
+partially matching substring. (Note that this is the entire substring that was
+inspected during the partial match; it may include characters before the actual
+match start if a lookbehind assertion, \eK, \eb, or \eB was involved.)
+.P
+If \fB/g\fP is present on the pattern, the search for further matches resumes
+at the end of the longest match. For example:
+.sp
+    re> /(tang|tangerine|tan)/g
+  data> yellow tangerine and tangy sultana\eD
+   0: tangerine
+   1: tang
+   2: tan
+   0: tang
+   1: tan
+   0: tan
+.sp
+Since the matching function does not support substring capture, the escape
+sequences that are concerned with captured substrings are not relevant.
+.
+.
+.SH "RESTARTING AFTER A PARTIAL MATCH"
+.rs
+.sp
+When the alternative matching function has given the PCRE_ERROR_PARTIAL return,
+indicating that the subject partially matched the pattern, you can restart the
+match with additional subject data by means of the \eR escape sequence. For
+example:
+.sp
+    re> /^\ed?\ed(jan|feb|mar|apr|may|jun|jul|aug|sep|oct|nov|dec)\ed\ed$/
+  data> 23ja\eP\eD
+  Partial match: 23ja
+  data> n05\eR\eD
+   0: n05
+.sp
+For further information about partial matching, see the
+.\" HREF
+\fBpcrepartial\fP
+.\"
+documentation.
+.
+.
+.SH CALLOUTS
+.rs
+.sp
+If the pattern contains any callout requests, \fBpcretest\fP's callout function
+is called during matching. This works with both matching functions. By default,
+the called function displays the callout number, the start and current
+positions in the text at the callout time, and the next pattern item to be
+tested. For example:
+.sp
+  --->pqrabcdef
+    0    ^  ^     \ed
+.sp
+This output indicates that callout number 0 occurred for a match attempt
+starting at the fourth character of the subject string, when the pointer was at
+the seventh character of the data, and when the next pattern item was \ed. Just
+one circumflex is output if the start and current positions are the same.
+.P
+Callouts numbered 255 are assumed to be automatic callouts, inserted as a
+result of the \fB/C\fP pattern modifier. In this case, instead of showing the
+callout number, the offset in the pattern, preceded by a plus, is output. For
+example:
+.sp
+    re> /\ed?[A-E]\e*/C
+  data> E*
+  --->E*
+   +0 ^      \ed?
+   +3 ^      [A-E]
+   +8 ^^     \e*
+  +10 ^ ^
+   0: E*
+.sp
+If a pattern contains (*MARK) items, an additional line is output whenever
+a change of latest mark is passed to the callout function. For example:
+.sp
+    re> /a(*MARK:X)bc/C
+  data> abc
+  --->abc
+   +0 ^       a
+   +1 ^^      (*MARK:X)
+  +10 ^^      b
+  Latest Mark: X
+  +11 ^ ^     c
+  +12 ^  ^
+   0: abc
+.sp
+The mark changes between matching "a" and "b", but stays the same for the rest
+of the match, so nothing more is output. If, as a result of backtracking, the
+mark reverts to being unset, the text "<unset>" is output.
+.P
+The callout function in \fBpcretest\fP returns zero (carry on matching) by
+default, but you can use a \eC item in a data line (as described above) to
+change this and other parameters of the callout.
+.P
+Inserting callouts can be helpful when using \fBpcretest\fP to check
+complicated regular expressions. For further information about callouts, see
+the
+.\" HREF
+\fBpcrecallout\fP
+.\"
+documentation.
+.
+.
+.
+.SH "NON-PRINTING CHARACTERS"
+.rs
+.sp
+When \fBpcretest\fP is outputting text in the compiled version of a pattern,
+bytes other than 32-126 are always treated as non-printing characters are are
+therefore shown as hex escapes.
+.P
+When \fBpcretest\fP is outputting text that is a matched part of a subject
+string, it behaves in the same way, unless a different locale has been set for
+the pattern (using the \fB/L\fP modifier). In this case, the \fBisprint()\fP
+function to distinguish printing and non-printing characters.
+.
+.
+.
+.SH "SAVING AND RELOADING COMPILED PATTERNS"
+.rs
+.sp
+The facilities described in this section are not available when the POSIX
+interface to PCRE is being used, that is, when the \fB/P\fP pattern modifier is
+specified.
+.P
+When the POSIX interface is not in use, you can cause \fBpcretest\fP to write a
+compiled pattern to a file, by following the modifiers with > and a file name.
+For example:
+.sp
+  /pattern/im >/some/file
+.sp
+See the
+.\" HREF
+\fBpcreprecompile\fP
+.\"
+documentation for a discussion about saving and re-using compiled patterns.
+Note that if the pattern was successfully studied with JIT optimization, the
+JIT data cannot be saved.
+.P
+The data that is written is binary. The first eight bytes are the length of the
+compiled pattern data followed by the length of the optional study data, each
+written as four bytes in big-endian order (most significant byte first). If
+there is no study data (either the pattern was not studied, or studying did not
+return any data), the second length is zero. The lengths are followed by an
+exact copy of the compiled pattern. If there is additional study data, this
+(excluding any JIT data) follows immediately after the compiled pattern. After
+writing the file, \fBpcretest\fP expects to read a new pattern.
+.P
+A saved pattern can be reloaded into \fBpcretest\fP by specifying < and a file
+name instead of a pattern. There must be no space between < and the file name,
+which must not contain a < character, as otherwise \fBpcretest\fP will
+interpret the line as a pattern delimited by < characters. For example:
+.sp
+   re> </some/file
+  Compiled pattern loaded from /some/file
+  No study data
+.sp
+If the pattern was previously studied with the JIT optimization, the JIT
+information cannot be saved and restored, and so is lost. When the pattern has
+been loaded, \fBpcretest\fP proceeds to read data lines in the usual way.
+.P
+You can copy a file written by \fBpcretest\fP to a different host and reload it
+there, even if the new host has opposite endianness to the one on which the
+pattern was compiled. For example, you can compile on an i86 machine and run on
+a SPARC machine. When a pattern is reloaded on a host with different
+endianness, the confirmation message is changed to:
+.sp
+  Compiled pattern (byte-inverted) loaded from /some/file
+.sp
+The test suite contains some saved pre-compiled patterns with different
+endianness. These are reloaded using "<!" instead of just "<". This suppresses
+the "(byte-inverted)" text so that the output is the same on all hosts. It also
+forces debugging output once the pattern has been reloaded.
+.P
+File names for saving and reloading can be absolute or relative, but note that
+the shell facility of expanding a file name that starts with a tilde (~) is not
+available.
+.P
+The ability to save and reload files in \fBpcretest\fP is intended for testing
+and experimentation. It is not intended for production use because only a
+single pattern can be written to a file. Furthermore, there is no facility for
+supplying custom character tables for use with a reloaded pattern. If the
+original pattern was compiled with custom tables, an attempt to match a subject
+string using a reloaded pattern is likely to cause \fBpcretest\fP to crash.
+Finally, if you attempt to load a file that is not in the correct format, the
+result is undefined.
+.
+.
+.SH "SEE ALSO"
+.rs
+.sp
+\fBpcre\fP(3), \fBpcre16\fP(3), \fBpcre32\fP(3), \fBpcreapi\fP(3),
+\fBpcrecallout\fP(3),
+\fBpcrejit\fP, \fBpcrematching\fP(3), \fBpcrepartial\fP(d),
+\fBpcrepattern\fP(3), \fBpcreprecompile\fP(3).
+.
+.
+.SH AUTHOR
+.rs
+.sp
+.nf
+Philip Hazel
+University Computing Service
+Cambridge CB2 3QH, England.
+.fi
+.
+.
+.SH REVISION
+.rs
+.sp
+.nf
+Last updated: 09 February 2014
+Copyright (c) 1997-2014 University of Cambridge.
+.fi
diff --git a/libs/Pcre16/docs/doc/pcretest.txt b/libs/Pcre16/docs/doc/pcretest.txt
new file mode 100644
index 0000000000..55de502443
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcretest.txt
@@ -0,0 +1,1087 @@
+PCRETEST(1)                 General Commands Manual                PCRETEST(1)
+
+
+
+NAME
+       pcretest - a program for testing Perl-compatible regular expressions.
+
+SYNOPSIS
+
+       pcretest [options] [input file [output file]]
+
+       pcretest  was written as a test program for the PCRE regular expression
+       library itself, but it can also be used for experimenting with  regular
+       expressions.  This document describes the features of the test program;
+       for details of the regular expressions themselves, see the  pcrepattern
+       documentation. For details of the PCRE library function calls and their
+       options, see the pcreapi , pcre16 and pcre32 documentation.
+
+       The input for pcretest is a sequence of regular expression patterns and
+       strings  to be matched, as described below. The output shows the result
+       of each match. Options on the command line  and  the  patterns  control
+       PCRE options and exactly what is output.
+
+       As  PCRE has evolved, it has acquired many different features, and as a
+       result, pcretest now has rather a lot of obscure  options  for  testing
+       every possible feature. Some of these options are specifically designed
+       for use in conjunction with the test script and  data  files  that  are
+       distributed  as  part of PCRE, and are unlikely to be of use otherwise.
+       They are all documented here, but without much justification.
+
+
+INPUT DATA FORMAT
+
+       Input to pcretest is processed line by line, either by  calling  the  C
+       library's fgets() function, or via the libreadline library (see below).
+       In Unix-like environments, fgets() treats any bytes other than  newline
+       as  data characters. However, in some Windows environments character 26
+       (hex 1A) causes an immediate end of file, and no further data is  read.
+       For  maximum  portability,  therefore,  it  is safest to use only ASCII
+       characters in pcretest input files.
+
+
+PCRE's 8-BIT, 16-BIT AND 32-BIT LIBRARIES
+
+       From release 8.30, two separate PCRE libraries can be built. The origi-
+       nal  one  supports  8-bit  character  strings, whereas the newer 16-bit
+       library supports  character  strings  encoded  in  16-bit  units.  From
+       release  8.32,  a  third  library  can  be  built, supporting character
+       strings encoded in 32-bit units. The pcretest program can  be  used  to
+       test all three libraries. However, it is itself still an 8-bit program,
+       reading 8-bit input and writing 8-bit output.  When testing the  16-bit
+       or  32-bit  library, the patterns and data strings are converted to 16-
+       or 32-bit format before being passed to  the  PCRE  library  functions.
+       Results are converted to 8-bit for output.
+
+       References to functions and structures of the form pcre[16|32]_xx below
+       mean "pcre_xx when using the 8-bit library, pcre16_xx  when  using  the
+       16-bit library, or pcre32_xx when using the 32-bit library".
+
+
+COMMAND LINE OPTIONS
+
+       -8        If  both the 8-bit library has been built, this option causes
+                 the 8-bit library to be used (which is the default);  if  the
+                 8-bit  library  has  not  been  built,  this option causes an
+                 error.
+
+       -16       If both the 8-bit or the 32-bit,  and  the  16-bit  libraries
+                 have  been built, this option causes the 16-bit library to be
+                 used. If only the 16-bit library has been built, this is  the
+                 default  (so  has no effect). If only the 8-bit or the 32-bit
+                 library has been built, this option causes an error.
+
+       -32       If both the 8-bit or the 16-bit,  and  the  32-bit  libraries
+                 have  been built, this option causes the 32-bit library to be
+                 used. If only the 32-bit library has been built, this is  the
+                 default  (so  has no effect). If only the 8-bit or the 16-bit
+                 library has been built, this option causes an error.
+
+       -b        Behave as if each pattern has the /B (show byte  code)  modi-
+                 fier; the internal form is output after compilation.
+
+       -C        Output the version number of the PCRE library, and all avail-
+                 able  information  about  the  optional  features  that   are
+                 included,  and  then  exit  with  zero  exit  code. All other
+                 options are ignored.
+
+       -C option Output information about a specific build-time  option,  then
+                 exit.  This functionality is intended for use in scripts such
+                 as RunTest. The following options output the  value  and  set
+                 the exit code as indicated:
+
+                   ebcdic-nl  the code for LF (= NL) in an EBCDIC environment:
+                                0x15 or 0x25
+                                0 if used in an ASCII environment
+                                exit code is always 0
+                   linksize   the configured internal link size (2, 3, or 4)
+                                exit code is set to the link size
+                   newline    the default newline setting:
+                                CR, LF, CRLF, ANYCRLF, or ANY
+                                exit code is always 0
+                   bsr        the default setting for what \R matches:
+                                ANYCRLF or ANY
+                                exit code is always 0
+
+                 The  following  options output 1 for true or 0 for false, and
+                 set the exit code to the same value:
+
+                   ebcdic     compiled for an EBCDIC environment
+                   jit        just-in-time support is available
+                   pcre16     the 16-bit library was built
+                   pcre32     the 32-bit library was built
+                   pcre8      the 8-bit library was built
+                   ucp        Unicode property support is available
+                   utf        UTF-8 and/or UTF-16 and/or UTF-32 support
+                                is available
+
+                 If an unknown option is given, an error  message  is  output;
+                 the exit code is 0.
+
+       -d        Behave  as  if  each pattern has the /D (debug) modifier; the
+                 internal form and information about the compiled  pattern  is
+                 output after compilation; -d is equivalent to -b -i.
+
+       -dfa      Behave  as if each data line contains the \D escape sequence;
+                 this    causes    the    alternative    matching    function,
+                 pcre[16|32]_dfa_exec(),  to  be  used instead of the standard
+                 pcre[16|32]_exec() function (more detail is given below).
+
+       -help     Output a brief summary these options and then exit.
+
+       -i        Behave as if each pattern has the  /I  modifier;  information
+                 about the compiled pattern is given after compilation.
+
+       -M        Behave  as if each data line contains the \M escape sequence;
+                 this causes PCRE to  discover  the  minimum  MATCH_LIMIT  and
+                 MATCH_LIMIT_RECURSION  settings by calling pcre[16|32]_exec()
+                 repeatedly with different limits.
+
+       -m        Output the size of each compiled pattern after  it  has  been
+                 compiled.  This  is  equivalent  to adding /M to each regular
+                 expression. The size is given in bytes for both libraries.
+
+       -O        Behave as if each pattern has the /O modifier, that  is  dis-
+                 able auto-possessification for all patterns.
+
+       -o osize  Set  the number of elements in the output vector that is used
+                 when calling pcre[16|32]_exec() or pcre[16|32]_dfa_exec()  to
+                 be  osize.  The  default  value is 45, which is enough for 14
+                 capturing subexpressions for pcre[16|32]_exec() or 22 differ-
+                 ent  matches for pcre[16|32]_dfa_exec().  The vector size can
+                 be changed for individual matching calls by including  \O  in
+                 the data line (see below).
+
+       -p        Behave  as  if  each  pattern  has the /P modifier; the POSIX
+                 wrapper API is used to call PCRE. None of the  other  options
+                 has  any  effect when -p is set. This option can be used only
+                 with the 8-bit library.
+
+       -q        Do not output the version number of pcretest at the start  of
+                 execution.
+
+       -S size   On  Unix-like  systems, set the size of the run-time stack to
+                 size megabytes.
+
+       -s or -s+ Behave as if each pattern  has  the  /S  modifier;  in  other
+                 words,  force each pattern to be studied. If -s+ is used, all
+                 the JIT compile options are  passed  to  pcre[16|32]_study(),
+                 causing  just-in-time  optimization  to  be  set  up if it is
+                 available, for both full and partial matching.  Specific  JIT
+                 compile options can be selected by following -s+ with a digit
+                 in the range 1 to 7, which selects the JIT compile  modes  as
+                 follows:
+
+                   1  normal match only
+                   2  soft partial match only
+                   3  normal match and soft partial match
+                   4  hard partial match only
+                   6  soft and hard partial match
+                   7  all three modes (default)
+
+                 If  -s++  is used instead of -s+ (with or without a following
+                 digit), the text "(JIT)" is added to the  first  output  line
+                 after a match or no match when JIT-compiled code was actually
+                 used.
+
+                 Note that there are pattern options  that  can  override  -s,
+                 either specifying no studying at all, or suppressing JIT com-
+                 pilation.
+
+                 If the /I or /D option is present on  a  pattern  (requesting
+                 output  about  the  compiled  pattern), information about the
+                 result of studying is not included when  studying  is  caused
+                 only  by  -s  and neither -i nor -d is present on the command
+                 line. This behaviour means that the output  from  tests  that
+                 are  run with and without -s should be identical, except when
+                 options that output information about the actual running of a
+                 match are set.
+
+                 The  -M,  -t,  and  -tm options, which give information about
+                 resources used, are likely to produce different  output  with
+                 and  without  -s.  Output may also differ if the /C option is
+                 present on an individual pattern. This uses callouts to trace
+                 the  the  matching process, and this may be different between
+                 studied and non-studied patterns.  If  the  pattern  contains
+                 (*MARK)  items  there  may  also be differences, for the same
+                 reason. The -s command line option can be overridden for spe-
+                 cific  patterns that should never be studied (see the /S pat-
+                 tern modifier below).
+
+       -t        Run each compile, study, and match many times with  a  timer,
+                 and  output  the resulting times per compile, study, or match
+                 (in milliseconds). Do not set -m with -t,  because  you  will
+                 then get the size output a zillion times, and the timing will
+                 be distorted. You can control the number of  iterations  that
+                 are used for timing by following -t with a number (as a sepa-
+                 rate item on the command line). For example, "-t 1000"  iter-
+                 ates 1000 times.  The default is to iterate 500000 times.
+
+       -tm       This is like -t except that it times only the matching phase,
+                 not the compile or study phases.
+
+       -T -TM    These behave like -t and -tm, but in addition, at the end  of
+                 a run, the total times for all compiles, studies, and matches
+                 are output.
+
+
+DESCRIPTION
+
+       If pcretest is given two filename arguments, it reads  from  the  first
+       and writes to the second. If it is given only one filename argument, it
+       reads from that file and writes to stdout.  Otherwise,  it  reads  from
+       stdin  and  writes to stdout, and prompts for each line of input, using
+       "re>" to prompt for regular expressions, and "data>" to prompt for data
+       lines.
+
+       When  pcretest  is  built,  a  configuration option can specify that it
+       should be linked with the libreadline library. When this  is  done,  if
+       the input is from a terminal, it is read using the readline() function.
+       This provides line-editing and history facilities. The output from  the
+       -help option states whether or not readline() will be used.
+
+       The program handles any number of sets of input on a single input file.
+       Each set starts with a regular expression, and continues with any  num-
+       ber of data lines to be matched against that pattern.
+
+       Each  data line is matched separately and independently. If you want to
+       do multi-line matches, you have to use the \n escape sequence (or \r or
+       \r\n, etc., depending on the newline setting) in a single line of input
+       to encode the newline sequences. There is no limit  on  the  length  of
+       data  lines;  the  input  buffer is automatically extended if it is too
+       small.
+
+       An empty line signals the end of the data lines, at which point  a  new
+       regular  expression is read. The regular expressions are given enclosed
+       in any non-alphanumeric delimiters other than backslash, for example:
+
+         /(a|bc)x+yz/
+
+       White space before the initial delimiter is ignored. A regular  expres-
+       sion  may be continued over several input lines, in which case the new-
+       line characters are included within it. It is possible to  include  the
+       delimiter within the pattern by escaping it, for example
+
+         /abc\/def/
+
+       If  you  do  so, the escape and the delimiter form part of the pattern,
+       but since delimiters are always non-alphanumeric, this does not  affect
+       its  interpretation.   If the terminating delimiter is immediately fol-
+       lowed by a backslash, for example,
+
+         /abc/\
+
+       then a backslash is added to the end of the pattern. This  is  done  to
+       provide  a  way of testing the error condition that arises if a pattern
+       finishes with a backslash, because
+
+         /abc\/
+
+       is interpreted as the first line of a pattern that starts with  "abc/",
+       causing pcretest to read the next line as a continuation of the regular
+       expression.
+
+
+PATTERN MODIFIERS
+
+       A pattern may be followed by any number of modifiers, which are  mostly
+       single  characters,  though  some  of these can be qualified by further
+       characters.  Following Perl usage, these are referred to below as,  for
+       example,  "the  /i  modifier", even though the delimiter of the pattern
+       need not always be a slash, and no slash is  used  when  writing  modi-
+       fiers.  White  space may appear between the final pattern delimiter and
+       the first modifier, and between the modifiers  themselves.  For  refer-
+       ence,  here  is  a  complete  list of modifiers. They fall into several
+       groups that are described in detail in the following sections.
+
+         /8              set UTF mode
+         /9              set PCRE_NEVER_UTF (locks out UTF mode)
+         /?              disable UTF validity check
+         /+              show remainder of subject after match
+         /=              show all captures (not just those that are set)
+
+         /A              set PCRE_ANCHORED
+         /B              show compiled code
+         /C              set PCRE_AUTO_CALLOUT
+         /D              same as /B plus /I
+         /E              set PCRE_DOLLAR_ENDONLY
+         /F              flip byte order in compiled pattern
+         /f              set PCRE_FIRSTLINE
+         /G              find all matches (shorten string)
+         /g              find all matches (use startoffset)
+         /I              show information about pattern
+         /i              set PCRE_CASELESS
+         /J              set PCRE_DUPNAMES
+         /K              show backtracking control names
+         /L              set locale
+         /M              show compiled memory size
+         /m              set PCRE_MULTILINE
+         /N              set PCRE_NO_AUTO_CAPTURE
+         /O              set PCRE_NO_AUTO_POSSESS
+         /P              use the POSIX wrapper
+         /Q              test external stack check function
+         /S              study the pattern after compilation
+         /s              set PCRE_DOTALL
+         /T              select character tables
+         /U              set PCRE_UNGREEDY
+         /W              set PCRE_UCP
+         /X              set PCRE_EXTRA
+         /x              set PCRE_EXTENDED
+         /Y              set PCRE_NO_START_OPTIMIZE
+         /Z              don't show lengths in /B output
+
+         /<any>          set PCRE_NEWLINE_ANY
+         /<anycrlf>      set PCRE_NEWLINE_ANYCRLF
+         /<cr>           set PCRE_NEWLINE_CR
+         /<crlf>         set PCRE_NEWLINE_CRLF
+         /<lf>           set PCRE_NEWLINE_LF
+         /<bsr_anycrlf>  set PCRE_BSR_ANYCRLF
+         /<bsr_unicode>  set PCRE_BSR_UNICODE
+         /<JS>           set PCRE_JAVASCRIPT_COMPAT
+
+
+   Perl-compatible modifiers
+
+       The /i, /m, /s, and /x modifiers set the PCRE_CASELESS, PCRE_MULTILINE,
+       PCRE_DOTALL,    or    PCRE_EXTENDED    options,    respectively,   when
+       pcre[16|32]_compile() is called. These four modifier letters  have  the
+       same effect as they do in Perl. For example:
+
+         /caseless/i
+
+
+   Modifiers for other PCRE options
+
+       The  following  table  shows additional modifiers for setting PCRE com-
+       pile-time options that do not correspond to anything in Perl:
+
+         /8              PCRE_UTF8           ) when using the 8-bit
+         /?              PCRE_NO_UTF8_CHECK  )   library
+
+         /8              PCRE_UTF16          ) when using the 16-bit
+         /?              PCRE_NO_UTF16_CHECK )   library
+
+         /8              PCRE_UTF32          ) when using the 32-bit
+         /?              PCRE_NO_UTF32_CHECK )   library
+
+         /9              PCRE_NEVER_UTF
+         /A              PCRE_ANCHORED
+         /C              PCRE_AUTO_CALLOUT
+         /E              PCRE_DOLLAR_ENDONLY
+         /f              PCRE_FIRSTLINE
+         /J              PCRE_DUPNAMES
+         /N              PCRE_NO_AUTO_CAPTURE
+         /O              PCRE_NO_AUTO_POSSESS
+         /U              PCRE_UNGREEDY
+         /W              PCRE_UCP
+         /X              PCRE_EXTRA
+         /Y              PCRE_NO_START_OPTIMIZE
+         /<any>          PCRE_NEWLINE_ANY
+         /<anycrlf>      PCRE_NEWLINE_ANYCRLF
+         /<cr>           PCRE_NEWLINE_CR
+         /<crlf>         PCRE_NEWLINE_CRLF
+         /<lf>           PCRE_NEWLINE_LF
+         /<bsr_anycrlf>  PCRE_BSR_ANYCRLF
+         /<bsr_unicode>  PCRE_BSR_UNICODE
+         /<JS>           PCRE_JAVASCRIPT_COMPAT
+
+       The modifiers that are enclosed in angle brackets are  literal  strings
+       as  shown,  including the angle brackets, but the letters within can be
+       in either case.  This example sets multiline matching with CRLF as  the
+       line ending sequence:
+
+         /^abc/m<CRLF>
+
+       As  well  as  turning  on  the  PCRE_UTF8/16/32 option, the /8 modifier
+       causes all non-printing characters in  output  strings  to  be  printed
+       using the \x{hh...} notation. Otherwise, those less than 0x100 are out-
+       put in hex without the curly brackets.
+
+       Full details of the PCRE options are given in  the  pcreapi  documenta-
+       tion.
+
+   Finding all matches in a string
+
+       Searching  for  all  possible matches within each subject string can be
+       requested by the /g or /G modifier. After  finding  a  match,  PCRE  is
+       called again to search the remainder of the subject string. The differ-
+       ence between /g and /G is that the former uses the startoffset argument
+       to  pcre[16|32]_exec()  to  start  searching  at a new point within the
+       entire string (which is in effect what Perl does), whereas  the  latter
+       passes  over  a  shortened  substring.  This  makes a difference to the
+       matching process if the pattern  begins  with  a  lookbehind  assertion
+       (including \b or \B).
+
+       If  any  call  to  pcre[16|32]_exec() in a /g or /G sequence matches an
+       empty string, the next call is done with the PCRE_NOTEMPTY_ATSTART  and
+       PCRE_ANCHORED  flags  set  in  order  to search for another, non-empty,
+       match at the same point. If this second match fails, the  start  offset
+       is  advanced,  and  the  normal match is retried. This imitates the way
+       Perl handles such cases when using the /g modifier or the split() func-
+       tion.  Normally,  the start offset is advanced by one character, but if
+       the newline convention recognizes CRLF as a newline,  and  the  current
+       character is CR followed by LF, an advance of two is used.
+
+   Other modifiers
+
+       There are yet more modifiers for controlling the way pcretest operates.
+
+       The  /+ modifier requests that as well as outputting the substring that
+       matched the entire pattern, pcretest  should  in  addition  output  the
+       remainder  of  the  subject  string. This is useful for tests where the
+       subject contains multiple copies of the same substring. If the +  modi-
+       fier  appears  twice, the same action is taken for captured substrings.
+       In each case the remainder is output on the following line with a  plus
+       character  following  the  capture number. Note that this modifier must
+       not immediately follow the /S modifier because /S+ and /S++ have  other
+       meanings.
+
+       The  /=  modifier  requests  that  the values of all potential captured
+       parentheses be output after a match. By default, only those up  to  the
+       highest one actually used in the match are output (corresponding to the
+       return code from pcre[16|32]_exec()). Values in the offsets vector cor-
+       responding  to higher numbers should be set to -1, and these are output
+       as "<unset>". This modifier gives a way of checking that this  is  hap-
+       pening.
+
+       The  /B modifier is a debugging feature. It requests that pcretest out-
+       put a representation of the compiled code after  compilation.  Normally
+       this  information  contains length and offset values; however, if /Z is
+       also present, this data is replaced by spaces. This is a  special  fea-
+       ture  for  use  in the automatic test scripts; it ensures that the same
+       output is generated for different internal link sizes.
+
+       The /D modifier is a PCRE debugging feature, and is equivalent to  /BI,
+       that is, both the /B and the /I modifiers.
+
+       The  /F  modifier  causes pcretest to flip the byte order of the 2-byte
+       and 4-byte fields in the compiled pattern. This facility is for testing
+       the  feature  in PCRE that allows it to execute patterns that were com-
+       piled on a host with a different endianness. This feature is not avail-
+       able  when the POSIX interface to PCRE is being used, that is, when the
+       /P pattern modifier is specified. See also the section about saving and
+       reloading compiled patterns below.
+
+       The  /I  modifier  requests  that pcretest output information about the
+       compiled pattern (whether it is anchored, has a fixed first  character,
+       and  so  on). It does this by calling pcre[16|32]_fullinfo() after com-
+       piling a pattern. If the pattern is studied, the results  of  that  are
+       also output. In this output, the word "char" means a non-UTF character,
+       that is, the value of a single data item  (8-bit,  16-bit,  or  32-bit,
+       depending on the library that is being tested).
+
+       The  /K modifier requests pcretest to show names from backtracking con-
+       trol verbs that are  returned  from  calls  to  pcre[16|32]_exec().  It
+       causes  pcretest  to  create  a  pcre[16|32]_extra block if one has not
+       already been created by a call to pcre[16|32]_study(), and to  set  the
+       PCRE_EXTRA_MARK  flag  and  the  mark  field within it, every time that
+       pcre[16|32]_exec() is called. If  the  variable  that  the  mark  field
+       points  to  is  non-NULL  for  a  match,  non-match,  or partial match,
+       pcretest prints the string to which it points. For  a  match,  this  is
+       shown  on  a  line  by itself, tagged with "MK:". For a non-match it is
+       added to the message.
+
+       The /L modifier must be followed directly by the name of a locale,  for
+       example,
+
+         /pattern/Lfr_FR
+
+       For this reason, it must be the last modifier. The given locale is set,
+       pcre[16|32]_maketables() is called to build a set of  character  tables
+       for  the  locale, and this is then passed to pcre[16|32]_compile() when
+       compiling the regular expression. Without an /L (or /T) modifier,  NULL
+       is  passed  as  the  tables  pointer;  that  is, /L applies only to the
+       expression on which it appears.
+
+       The /M modifier causes the size in bytes of the memory  block  used  to
+       hold  the compiled pattern to be output. This does not include the size
+       of the pcre[16|32] block; it is just the actual compiled data.  If  the
+       pattern is successfully studied with the PCRE_STUDY_JIT_COMPILE option,
+       the size of the JIT compiled code is also output.
+
+       The /Q modifier is used to test the use of pcre_stack_guard. It must be
+       followed  by '0' or '1', specifying the return code to be given from an
+       external function that is passed to PCRE and used  for  stack  checking
+       during compilation (see the pcreapi documentation for details).
+
+       The  /S  modifier  causes  pcre[16|32]_study()  to  be called after the
+       expression has been compiled, and the results used when the  expression
+       is matched. There are a number of qualifying characters that may follow
+       /S.  They may appear in any order.
+
+       If /S is followed by an exclamation mark, pcre[16|32]_study() is called
+       with  the PCRE_STUDY_EXTRA_NEEDED option, causing it always to return a
+       pcre_extra block, even when studying discovers no useful information.
+
+       If /S is followed by a second S character, it suppresses studying, even
+       if  it  was  requested  externally  by the -s command line option. This
+       makes it possible to specify that certain patterns are always  studied,
+       and others are never studied, independently of -s. This feature is used
+       in the test files in a few cases where the output is different when the
+       pattern is studied.
+
+       If  the  /S  modifier  is  followed  by  a  +  character,  the  call to
+       pcre[16|32]_study() is made with all the JIT study options,  requesting
+       just-in-time  optimization  support if it is available, for both normal
+       and partial matching. If you want to restrict the JIT compiling  modes,
+       you can follow /S+ with a digit in the range 1 to 7:
+
+         1  normal match only
+         2  soft partial match only
+         3  normal match and soft partial match
+         4  hard partial match only
+         6  soft and hard partial match
+         7  all three modes (default)
+
+       If /S++ is used instead of /S+ (with or without a following digit), the
+       text "(JIT)" is added to the first output line  after  a  match  or  no
+       match when JIT-compiled code was actually used.
+
+       Note  that  there  is  also  an independent /+ modifier; it must not be
+       given immediately after /S or /S+ because this will be misinterpreted.
+
+       If JIT studying is successful, the compiled JIT code will automatically
+       be  used  when pcre[16|32]_exec() is run, except when incompatible run-
+       time options are specified. For more details, see the pcrejit  documen-
+       tation.  See also the \J escape sequence below for a way of setting the
+       size of the JIT stack.
+
+       Finally, if /S is followed by a minus  character,  JIT  compilation  is
+       suppressed,  even if it was requested externally by the -s command line
+       option. This makes it possible to specify that JIT is never to be  used
+       for certain patterns.
+
+       The  /T  modifier  must be followed by a single digit. It causes a spe-
+       cific set of built-in character tables to be passed to pcre[16|32]_com-
+       pile().  It  is used in the standard PCRE tests to check behaviour with
+       different character tables. The digit specifies the tables as follows:
+
+         0   the default ASCII tables, as distributed in
+               pcre_chartables.c.dist
+         1   a set of tables defining ISO 8859 characters
+
+       In table 1, some characters whose codes are greater than 128 are  iden-
+       tified as letters, digits, spaces, etc.
+
+   Using the POSIX wrapper API
+
+       The  /P modifier causes pcretest to call PCRE via the POSIX wrapper API
+       rather than its native API. This supports only the 8-bit library.  When
+       /P  is set, the following modifiers set options for the regcomp() func-
+       tion:
+
+         /i    REG_ICASE
+         /m    REG_NEWLINE
+         /N    REG_NOSUB
+         /s    REG_DOTALL     )
+         /U    REG_UNGREEDY   ) These options are not part of
+         /W    REG_UCP        )   the POSIX standard
+         /8    REG_UTF8       )
+
+       The /+ modifier works as  described  above.  All  other  modifiers  are
+       ignored.
+
+   Locking out certain modifiers
+
+       PCRE  can be compiled with or without support for certain features such
+       as UTF-8/16/32 or Unicode properties. Accordingly, the  standard  tests
+       are  split  up  into  a number of different files that are selected for
+       running depending on which features are available.  When  updating  the
+       tests, it is all too easy to put a new test into the wrong file by mis-
+       take; for example, to put a test that requires UTF support into a  file
+       that  is used when it is not available. To help detect such mistakes as
+       early as possible, there is a facility for locking out  specific  modi-
+       fiers. If an input line for pcretest starts with the string "< forbid "
+       the following sequence of characters is taken as a  list  of  forbidden
+       modifiers. For example, in the test files that must not use UTF or Uni-
+       code property support, this line appears:
+
+         < forbid 8W
+
+       This locks out the /8 and /W modifiers. An immediate error is given  if
+       they  are  subsequently encountered. If the character string contains <
+       but not >, all the multi-character modifiers  that  begin  with  <  are
+       locked  out.  Otherwise,  such modifiers must be explicitly listed, for
+       example:
+
+         < forbid <JS><cr>
+
+       There must be a single space between < and "forbid" for this feature to
+       be  recognised.  If  there  is not, the line is interpreted either as a
+       request to re-load a pre-compiled pattern (see  "SAVING  AND  RELOADING
+       COMPILED  PATTERNS"  below) or, if there is a another < character, as a
+       pattern that uses < as its delimiter.
+
+
+DATA LINES
+
+       Before each data line is  passed  to  pcre[16|32]_exec(),  leading  and
+       trailing  white space is removed, and it is then scanned for \ escapes.
+       Some of these are pretty esoteric features, intended for  checking  out
+       some  of the more complicated features of PCRE. If you are just testing
+       "ordinary" regular expressions, you probably don't need any  of  these.
+       The following escapes are recognized:
+
+         \a         alarm (BEL, \x07)
+         \b         backspace (\x08)
+         \e         escape (\x27)
+         \f         form feed (\x0c)
+         \n         newline (\x0a)
+         \qdd       set the PCRE_MATCH_LIMIT limit to dd
+                      (any number of digits)
+         \r         carriage return (\x0d)
+         \t         tab (\x09)
+         \v         vertical tab (\x0b)
+         \nnn       octal character (up to 3 octal digits); always
+                      a byte unless > 255 in UTF-8 or 16-bit or 32-bit mode
+         \o{dd...}  octal character (any number of octal digits}
+         \xhh       hexadecimal byte (up to 2 hex digits)
+         \x{hh...}  hexadecimal character (any number of hex digits)
+         \A         pass the PCRE_ANCHORED option to pcre[16|32]_exec()
+                      or pcre[16|32]_dfa_exec()
+         \B         pass the PCRE_NOTBOL option to pcre[16|32]_exec()
+                      or pcre[16|32]_dfa_exec()
+         \Cdd       call pcre[16|32]_copy_substring() for substring dd
+                      after a successful match (number less than 32)
+         \Cname     call pcre[16|32]_copy_named_substring() for substring
+                      "name" after a successful match (name termin-
+                      ated by next non alphanumeric character)
+         \C+        show the current captured substrings at callout
+                      time
+         \C-        do not supply a callout function
+         \C!n       return 1 instead of 0 when callout number n is
+                      reached
+         \C!n!m     return 1 instead of 0 when callout number n is
+                      reached for the nth time
+         \C*n       pass the number n (may be negative) as callout
+                      data; this is used as the callout return value
+         \D         use the pcre[16|32]_dfa_exec() match function
+         \F         only shortest match for pcre[16|32]_dfa_exec()
+         \Gdd       call pcre[16|32]_get_substring() for substring dd
+                      after a successful match (number less than 32)
+         \Gname     call pcre[16|32]_get_named_substring() for substring
+                      "name" after a successful match (name termin-
+                      ated by next non-alphanumeric character)
+         \Jdd       set up a JIT stack of dd kilobytes maximum (any
+                      number of digits)
+         \L         call pcre[16|32]_get_substringlist() after a
+                      successful match
+         \M         discover the minimum MATCH_LIMIT and
+                      MATCH_LIMIT_RECURSION settings
+         \N         pass the PCRE_NOTEMPTY option to pcre[16|32]_exec()
+                      or pcre[16|32]_dfa_exec(); if used twice, pass the
+                      PCRE_NOTEMPTY_ATSTART option
+         \Odd       set the size of the output vector passed to
+                      pcre[16|32]_exec() to dd (any number of digits)
+         \P         pass the PCRE_PARTIAL_SOFT option to pcre[16|32]_exec()
+                      or pcre[16|32]_dfa_exec(); if used twice, pass the
+                      PCRE_PARTIAL_HARD option
+         \Qdd       set the PCRE_MATCH_LIMIT_RECURSION limit to dd
+                      (any number of digits)
+         \R         pass the PCRE_DFA_RESTART option to pcre[16|32]_dfa_exec()
+         \S         output details of memory get/free calls during matching
+         \Y             pass     the    PCRE_NO_START_OPTIMIZE    option    to
+       pcre[16|32]_exec()
+                      or pcre[16|32]_dfa_exec()
+         \Z         pass the PCRE_NOTEOL option to pcre[16|32]_exec()
+                      or pcre[16|32]_dfa_exec()
+         \?         pass the PCRE_NO_UTF[8|16|32]_CHECK option to
+                      pcre[16|32]_exec() or pcre[16|32]_dfa_exec()
+         \>dd       start the match at offset dd (optional "-"; then
+                      any number of digits); this sets the startoffset
+                      argument        for        pcre[16|32]_exec()         or
+       pcre[16|32]_dfa_exec()
+         \<cr>      pass the PCRE_NEWLINE_CR option to pcre[16|32]_exec()
+                      or pcre[16|32]_dfa_exec()
+         \<lf>      pass the PCRE_NEWLINE_LF option to pcre[16|32]_exec()
+                      or pcre[16|32]_dfa_exec()
+         \<crlf>    pass the PCRE_NEWLINE_CRLF option to pcre[16|32]_exec()
+                      or pcre[16|32]_dfa_exec()
+         \<anycrlf> pass the PCRE_NEWLINE_ANYCRLF option to pcre[16|32]_exec()
+                      or pcre[16|32]_dfa_exec()
+         \<any>     pass the PCRE_NEWLINE_ANY option to pcre[16|32]_exec()
+                      or pcre[16|32]_dfa_exec()
+
+       The  use of \x{hh...} is not dependent on the use of the /8 modifier on
+       the pattern. It is recognized always. There may be any number of  hexa-
+       decimal  digits  inside  the  braces; invalid values provoke error mes-
+       sages.
+
+       Note that \xhh specifies one byte rather than one  character  in  UTF-8
+       mode;  this  makes it possible to construct invalid UTF-8 sequences for
+       testing purposes. On the other hand, \x{hh} is interpreted as  a  UTF-8
+       character  in UTF-8 mode, generating more than one byte if the value is
+       greater than 127.  When testing the 8-bit library not  in  UTF-8  mode,
+       \x{hh} generates one byte for values less than 256, and causes an error
+       for greater values.
+
+       In UTF-16 mode, all 4-digit \x{hhhh} values are accepted. This makes it
+       possible to construct invalid UTF-16 sequences for testing purposes.
+
+       In  UTF-32  mode,  all  4- to 8-digit \x{...} values are accepted. This
+       makes it possible to construct invalid  UTF-32  sequences  for  testing
+       purposes.
+
+       The  escapes  that  specify  line ending sequences are literal strings,
+       exactly as shown. No more than one newline setting should be present in
+       any data line.
+
+       A  backslash  followed by anything else just escapes the anything else.
+       If the very last character is a backslash, it is ignored. This gives  a
+       way  of  passing  an empty line as data, since a real empty line termi-
+       nates the data input.
+
+       The \J escape provides a way of setting the maximum stack size that  is
+       used  by the just-in-time optimization code. It is ignored if JIT opti-
+       mization is not being used. Providing a stack that is larger  than  the
+       default 32K is necessary only for very complicated patterns.
+
+       If \M is present, pcretest calls pcre[16|32]_exec() several times, with
+       different values in the match_limit and match_limit_recursion fields of
+       the  pcre[16|32]_extra  data structure, until it finds the minimum num-
+       bers for each parameter that allow pcre[16|32]_exec() to complete with-
+       out  error.  Because  this  is testing a specific feature of the normal
+       interpretive pcre[16|32]_exec() execution, the use of any JIT optimiza-
+       tion  that might have been set up by the /S+ qualifier of -s+ option is
+       disabled.
+
+       The match_limit number is a measure of the amount of backtracking  that
+       takes  place,  and  checking it out can be instructive. For most simple
+       matches, the number is quite small, but for patterns  with  very  large
+       numbers  of  matching  possibilities,  it can become large very quickly
+       with increasing length of  subject  string.  The  match_limit_recursion
+       number  is  a  measure  of how much stack (or, if PCRE is compiled with
+       NO_RECURSE, how much heap) memory  is  needed  to  complete  the  match
+       attempt.
+
+       When  \O  is  used, the value specified may be higher or lower than the
+       size set by the -O command line option (or defaulted to 45); \O applies
+       only  to  the  call  of  pcre[16|32]_exec()  for  the  line in which it
+       appears.
+
+       If the /P modifier was present on the pattern, causing the POSIX  wrap-
+       per  API  to  be  used, the only option-setting sequences that have any
+       effect are \B,  \N,  and  \Z,  causing  REG_NOTBOL,  REG_NOTEMPTY,  and
+       REG_NOTEOL, respectively, to be passed to regexec().
+
+
+THE ALTERNATIVE MATCHING FUNCTION
+
+       By   default,  pcretest  uses  the  standard  PCRE  matching  function,
+       pcre[16|32]_exec() to match each  data  line.  PCRE  also  supports  an
+       alternative  matching  function, pcre[16|32]_dfa_test(), which operates
+       in a different way, and has some restrictions. The differences  between
+       the two functions are described in the pcrematching documentation.
+
+       If  a data line contains the \D escape sequence, or if the command line
+       contains the -dfa option, the alternative matching  function  is  used.
+       This function finds all possible matches at a given point. If, however,
+       the \F escape sequence is present in the data line, it stops after  the
+       first match is found. This is always the shortest possible match.
+
+
+DEFAULT OUTPUT FROM PCRETEST
+
+       This  section  describes  the output when the normal matching function,
+       pcre[16|32]_exec(), is being used.
+
+       When a match succeeds, pcretest outputs the list of captured substrings
+       that  pcre[16|32]_exec() returns, starting with number 0 for the string
+       that matched the whole pattern. Otherwise, it outputs "No  match"  when
+       the  return is PCRE_ERROR_NOMATCH, and "Partial match:" followed by the
+       partially   matching   substring   when   pcre[16|32]_exec()    returns
+       PCRE_ERROR_PARTIAL.  (Note  that  this is the entire substring that was
+       inspected during the partial match; it may  include  characters  before
+       the  actual  match  start  if a lookbehind assertion, \K, \b, or \B was
+       involved.) For any other return, pcretest  outputs  the  PCRE  negative
+       error  number  and a short descriptive phrase. If the error is a failed
+       UTF string check, the offset of the start of the failing character  and
+       the  reason  code are also output, provided that the size of the output
+       vector is at least two. Here is an example of an  interactive  pcretest
+       run.
+
+         $ pcretest
+         PCRE version 8.13 2011-04-30
+
+           re> /^abc(\d+)/
+         data> abc123
+          0: abc123
+          1: 123
+         data> xyz
+         No match
+
+       Unset capturing substrings that are not followed by one that is set are
+       not returned by pcre[16|32]_exec(), and are not shown by  pcretest.  In
+       the following example, there are two capturing substrings, but when the
+       first data line is matched, the second, unset substring is  not  shown.
+       An  "internal" unset substring is shown as "<unset>", as for the second
+       data line.
+
+           re> /(a)|(b)/
+         data> a
+          0: a
+          1: a
+         data> b
+          0: b
+          1: <unset>
+          2: b
+
+       If the strings contain any non-printing characters, they are output  as
+       \xhh  escapes  if  the  value is less than 256 and UTF mode is not set.
+       Otherwise they are output as \x{hh...} escapes. See below for the defi-
+       nition  of non-printing characters. If the pattern has the /+ modifier,
+       the output for substring 0 is followed by the the rest of  the  subject
+       string, identified by "0+" like this:
+
+           re> /cat/+
+         data> cataract
+          0: cat
+          0+ aract
+
+       If  the  pattern  has  the /g or /G modifier, the results of successive
+       matching attempts are output in sequence, like this:
+
+           re> /\Bi(\w\w)/g
+         data> Mississippi
+          0: iss
+          1: ss
+          0: iss
+          1: ss
+          0: ipp
+          1: pp
+
+       "No match" is output only if the first match attempt fails. Here is  an
+       example  of a failure message (the offset 4 that is specified by \>4 is
+       past the end of the subject string):
+
+           re> /xyz/
+         data> xyz\>4
+         Error -24 (bad offset value)
+
+       If any of the sequences \C, \G, or \L are present in a data  line  that
+       is  successfully  matched,  the substrings extracted by the convenience
+       functions are output with C, G, or L after the string number instead of
+       a colon. This is in addition to the normal full list. The string length
+       (that is, the return from the extraction function) is given  in  paren-
+       theses after each string for \C and \G.
+
+       Note that whereas patterns can be continued over several lines (a plain
+       ">" prompt is used for continuations), data lines may not. However new-
+       lines  can  be included in data by means of the \n escape (or \r, \r\n,
+       etc., depending on the newline sequence setting).
+
+
+OUTPUT FROM THE ALTERNATIVE MATCHING FUNCTION
+
+       When the alternative matching function, pcre[16|32]_dfa_exec(), is used
+       (by  means  of the \D escape sequence or the -dfa command line option),
+       the output consists of a list of all the  matches  that  start  at  the
+       first point in the subject where there is at least one match. For exam-
+       ple:
+
+           re> /(tang|tangerine|tan)/
+         data> yellow tangerine\D
+          0: tangerine
+          1: tang
+          2: tan
+
+       (Using the normal matching function on this data  finds  only  "tang".)
+       The  longest matching string is always given first (and numbered zero).
+       After a PCRE_ERROR_PARTIAL return, the output is "Partial match:", fol-
+       lowed  by  the  partially  matching  substring.  (Note that this is the
+       entire substring that was inspected during the partial  match;  it  may
+       include characters before the actual match start if a lookbehind asser-
+       tion, \K, \b, or \B was involved.)
+
+       If /g is present on the pattern, the search for further matches resumes
+       at the end of the longest match. For example:
+
+           re> /(tang|tangerine|tan)/g
+         data> yellow tangerine and tangy sultana\D
+          0: tangerine
+          1: tang
+          2: tan
+          0: tang
+          1: tan
+          0: tan
+
+       Since  the  matching  function  does not support substring capture, the
+       escape sequences that are concerned with captured  substrings  are  not
+       relevant.
+
+
+RESTARTING AFTER A PARTIAL MATCH
+
+       When the alternative matching function has given the PCRE_ERROR_PARTIAL
+       return, indicating that the subject partially matched the pattern,  you
+       can  restart  the match with additional subject data by means of the \R
+       escape sequence. For example:
+
+           re> /^\d?\d(jan|feb|mar|apr|may|jun|jul|aug|sep|oct|nov|dec)\d\d$/
+         data> 23ja\P\D
+         Partial match: 23ja
+         data> n05\R\D
+          0: n05
+
+       For further information about partial  matching,  see  the  pcrepartial
+       documentation.
+
+
+CALLOUTS
+
+       If  the pattern contains any callout requests, pcretest's callout func-
+       tion is called during matching. This works  with  both  matching  func-
+       tions. By default, the called function displays the callout number, the
+       start and current positions in the text at the callout  time,  and  the
+       next pattern item to be tested. For example:
+
+         --->pqrabcdef
+           0    ^  ^     \d
+
+       This  output  indicates  that  callout  number  0  occurred for a match
+       attempt starting at the fourth character of the  subject  string,  when
+       the pointer was at the seventh character of the data, and when the next
+       pattern item was \d. Just one circumflex is output  if  the  start  and
+       current positions are the same.
+
+       Callouts numbered 255 are assumed to be automatic callouts, inserted as
+       a result of the /C pattern modifier. In this case, instead  of  showing
+       the  callout  number, the offset in the pattern, preceded by a plus, is
+       output. For example:
+
+           re> /\d?[A-E]\*/C
+         data> E*
+         --->E*
+          +0 ^      \d?
+          +3 ^      [A-E]
+          +8 ^^     \*
+         +10 ^ ^
+          0: E*
+
+       If a pattern contains (*MARK) items, an additional line is output when-
+       ever  a  change  of  latest mark is passed to the callout function. For
+       example:
+
+           re> /a(*MARK:X)bc/C
+         data> abc
+         --->abc
+          +0 ^       a
+          +1 ^^      (*MARK:X)
+         +10 ^^      b
+         Latest Mark: X
+         +11 ^ ^     c
+         +12 ^  ^
+          0: abc
+
+       The mark changes between matching "a" and "b", but stays the  same  for
+       the  rest  of  the match, so nothing more is output. If, as a result of
+       backtracking, the mark reverts to being unset, the  text  "<unset>"  is
+       output.
+
+       The  callout  function  in pcretest returns zero (carry on matching) by
+       default, but you can use a \C item in a data line (as described  above)
+       to change this and other parameters of the callout.
+
+       Inserting  callouts can be helpful when using pcretest to check compli-
+       cated regular expressions. For further information about callouts,  see
+       the pcrecallout documentation.
+
+
+NON-PRINTING CHARACTERS
+
+       When  pcretest is outputting text in the compiled version of a pattern,
+       bytes other than 32-126 are always treated as  non-printing  characters
+       are are therefore shown as hex escapes.
+
+       When  pcretest  is  outputting text that is a matched part of a subject
+       string, it behaves in the same way, unless a different locale has  been
+       set  for  the  pattern  (using  the  /L  modifier).  In  this case, the
+       isprint() function to distinguish printing and non-printing characters.
+
+
+SAVING AND RELOADING COMPILED PATTERNS
+
+       The facilities described in this section are  not  available  when  the
+       POSIX  interface  to  PCRE  is being used, that is, when the /P pattern
+       modifier is specified.
+
+       When the POSIX interface is not in use, you can cause pcretest to write
+       a  compiled  pattern to a file, by following the modifiers with > and a
+       file name.  For example:
+
+         /pattern/im >/some/file
+
+       See the pcreprecompile documentation for a discussion about saving  and
+       re-using  compiled patterns.  Note that if the pattern was successfully
+       studied with JIT optimization, the JIT data cannot be saved.
+
+       The data that is written is binary.  The  first  eight  bytes  are  the
+       length  of  the  compiled  pattern  data  followed by the length of the
+       optional study data, each written as four  bytes  in  big-endian  order
+       (most  significant  byte  first). If there is no study data (either the
+       pattern was not studied, or studying did not return any data), the sec-
+       ond  length  is  zero. The lengths are followed by an exact copy of the
+       compiled pattern. If there is additional study  data,  this  (excluding
+       any  JIT  data)  follows  immediately after the compiled pattern. After
+       writing the file, pcretest expects to read a new pattern.
+
+       A saved pattern can be reloaded into pcretest by  specifying  <  and  a
+       file  name  instead  of a pattern. There must be no space between < and
+       the file name, which must not  contain  a  <  character,  as  otherwise
+       pcretest  will  interpret  the line as a pattern delimited by < charac-
+       ters. For example:
+
+          re> </some/file
+         Compiled pattern loaded from /some/file
+         No study data
+
+       If the pattern was previously studied with the  JIT  optimization,  the
+       JIT  information cannot be saved and restored, and so is lost. When the
+       pattern has been loaded, pcretest proceeds to read data  lines  in  the
+       usual way.
+
+       You  can copy a file written by pcretest to a different host and reload
+       it there, even if the new host has opposite endianness to  the  one  on
+       which  the pattern was compiled. For example, you can compile on an i86
+       machine and run on a SPARC machine. When a pattern  is  reloaded  on  a
+       host with different endianness, the confirmation message is changed to:
+
+         Compiled pattern (byte-inverted) loaded from /some/file
+
+       The test suite contains some saved pre-compiled patterns with different
+       endianness. These are reloaded using "<!" instead  of  just  "<".  This
+       suppresses the "(byte-inverted)" text so that the output is the same on
+       all hosts. It also forces debugging output once the  pattern  has  been
+       reloaded.
+
+       File  names  for  saving and reloading can be absolute or relative, but
+       note that the shell facility of expanding a file name that starts  with
+       a tilde (~) is not available.
+
+       The  ability to save and reload files in pcretest is intended for test-
+       ing and experimentation. It is not intended for production use  because
+       only  a  single pattern can be written to a file. Furthermore, there is
+       no facility for supplying  custom  character  tables  for  use  with  a
+       reloaded  pattern.  If  the  original  pattern was compiled with custom
+       tables, an attempt to match a subject string using a  reloaded  pattern
+       is  likely to cause pcretest to crash.  Finally, if you attempt to load
+       a file that is not in the correct format, the result is undefined.
+
+
+SEE ALSO
+
+       pcre(3), pcre16(3),  pcre32(3),  pcreapi(3),  pcrecallout(3),  pcrejit,
+       pcrematching(3), pcrepartial(d), pcrepattern(3), pcreprecompile(3).
+
+
+AUTHOR
+
+       Philip Hazel
+       University Computing Service
+       Cambridge CB2 3QH, England.
+
+
+REVISION
+
+       Last updated: 09 February 2014
+       Copyright (c) 1997-2014 University of Cambridge.
diff --git a/libs/Pcre16/docs/doc/pcreunicode.3 b/libs/Pcre16/docs/doc/pcreunicode.3
new file mode 100644
index 0000000000..cb5e5269a4
--- /dev/null
+++ b/libs/Pcre16/docs/doc/pcreunicode.3
@@ -0,0 +1,249 @@
+.TH PCREUNICODE 3 "27 February 2013" "PCRE 8.33"
+.SH NAME
+PCRE - Perl-compatible regular expressions
+.SH "UTF-8, UTF-16, UTF-32, AND UNICODE PROPERTY SUPPORT"
+.rs
+.sp
+As well as UTF-8 support, PCRE also supports UTF-16 (from release 8.30) and
+UTF-32 (from release 8.32), by means of two additional libraries. They can be
+built as well as, or instead of, the 8-bit library.
+.
+.
+.SH "UTF-8 SUPPORT"
+.rs
+.sp
+In order process UTF-8 strings, you must build PCRE's 8-bit library with UTF
+support, and, in addition, you must call
+.\" HREF
+\fBpcre_compile()\fP
+.\"
+with the PCRE_UTF8 option flag, or the pattern must start with the sequence
+(*UTF8) or (*UTF). When either of these is the case, both the pattern and any
+subject strings that are matched against it are treated as UTF-8 strings
+instead of strings of individual 1-byte characters.
+.
+.
+.SH "UTF-16 AND UTF-32 SUPPORT"
+.rs
+.sp
+In order process UTF-16 or UTF-32 strings, you must build PCRE's 16-bit or
+32-bit library with UTF support, and, in addition, you must call
+.\" HREF
+\fBpcre16_compile()\fP
+.\"
+or
+.\" HREF
+\fBpcre32_compile()\fP
+.\"
+with the PCRE_UTF16 or PCRE_UTF32 option flag, as appropriate. Alternatively,
+the pattern must start with the sequence (*UTF16), (*UTF32), as appropriate, or
+(*UTF), which can be used with either library. When UTF mode is set, both the
+pattern and any subject strings that are matched against it are treated as
+UTF-16 or UTF-32 strings instead of strings of individual 16-bit or 32-bit
+characters.
+.
+.
+.SH "UTF SUPPORT OVERHEAD"
+.rs
+.sp
+If you compile PCRE with UTF support, but do not use it at run time, the
+library will be a bit bigger, but the additional run time overhead is limited
+to testing the PCRE_UTF[8|16|32] flag occasionally, so should not be very big.
+.
+.
+.SH "UNICODE PROPERTY SUPPORT"
+.rs
+.sp
+If PCRE is built with Unicode character property support (which implies UTF
+support), the escape sequences \ep{..}, \eP{..}, and \eX can be used.
+The available properties that can be tested are limited to the general
+category properties such as Lu for an upper case letter or Nd for a decimal
+number, the Unicode script names such as Arabic or Han, and the derived
+properties Any and L&. Full lists is given in the
+.\" HREF
+\fBpcrepattern\fP
+.\"
+and
+.\" HREF
+\fBpcresyntax\fP
+.\"
+documentation. Only the short names for properties are supported. For example,
+\ep{L} matches a letter. Its Perl synonym, \ep{Letter}, is not supported.
+Furthermore, in Perl, many properties may optionally be prefixed by "Is", for
+compatibility with Perl 5.6. PCRE does not support this.
+.
+.
+.\" HTML <a name="utf8strings"></a>
+.SS "Validity of UTF-8 strings"
+.rs
+.sp
+When you set the PCRE_UTF8 flag, the byte strings passed as patterns and
+subjects are (by default) checked for validity on entry to the relevant
+functions. The entire string is checked before any other processing takes
+place. From release 7.3 of PCRE, the check is according the rules of RFC 3629,
+which are themselves derived from the Unicode specification. Earlier releases
+of PCRE followed the rules of RFC 2279, which allows the full range of 31-bit
+values (0 to 0x7FFFFFFF). The current check allows only values in the range U+0
+to U+10FFFF, excluding the surrogate area. (From release 8.33 the so-called
+"non-character" code points are no longer excluded because Unicode corrigendum
+#9 makes it clear that they should not be.)
+.P
+Characters in the "Surrogate Area" of Unicode are reserved for use by UTF-16,
+where they are used in pairs to encode codepoints with values greater than
+0xFFFF. The code points that are encoded by UTF-16 pairs are available
+independently in the UTF-8 and UTF-32 encodings. (In other words, the whole
+surrogate thing is a fudge for UTF-16 which unfortunately messes up UTF-8 and
+UTF-32.)
+.P
+If an invalid UTF-8 string is passed to PCRE, an error return is given. At
+compile time, the only additional information is the offset to the first byte
+of the failing character. The run-time functions \fBpcre_exec()\fP and
+\fBpcre_dfa_exec()\fP also pass back this information, as well as a more
+detailed reason code if the caller has provided memory in which to do this.
+.P
+In some situations, you may already know that your strings are valid, and
+therefore want to skip these checks in order to improve performance, for
+example in the case of a long subject string that is being scanned repeatedly.
+If you set the PCRE_NO_UTF8_CHECK flag at compile time or at run time, PCRE
+assumes that the pattern or subject it is given (respectively) contains only
+valid UTF-8 codes. In this case, it does not diagnose an invalid UTF-8 string.
+.P
+Note that passing PCRE_NO_UTF8_CHECK to \fBpcre_compile()\fP just disables the
+check for the pattern; it does not also apply to subject strings. If you want
+to disable the check for a subject string you must pass this option to
+\fBpcre_exec()\fP or \fBpcre_dfa_exec()\fP.
+.P
+If you pass an invalid UTF-8 string when PCRE_NO_UTF8_CHECK is set, the result
+is undefined and your program may crash.
+.
+.
+.\" HTML <a name="utf16strings"></a>
+.SS "Validity of UTF-16 strings"
+.rs
+.sp
+When you set the PCRE_UTF16 flag, the strings of 16-bit data units that are
+passed as patterns and subjects are (by default) checked for validity on entry
+to the relevant functions. Values other than those in the surrogate range
+U+D800 to U+DFFF are independent code points. Values in the surrogate range
+must be used in pairs in the correct manner.
+.P
+If an invalid UTF-16 string is passed to PCRE, an error return is given. At
+compile time, the only additional information is the offset to the first data
+unit of the failing character. The run-time functions \fBpcre16_exec()\fP and
+\fBpcre16_dfa_exec()\fP also pass back this information, as well as a more
+detailed reason code if the caller has provided memory in which to do this.
+.P
+In some situations, you may already know that your strings are valid, and
+therefore want to skip these checks in order to improve performance. If you set
+the PCRE_NO_UTF16_CHECK flag at compile time or at run time, PCRE assumes that
+the pattern or subject it is given (respectively) contains only valid UTF-16
+sequences. In this case, it does not diagnose an invalid UTF-16 string.
+However, if an invalid string is passed, the result is undefined.
+.
+.
+.\" HTML <a name="utf32strings"></a>
+.SS "Validity of UTF-32 strings"
+.rs
+.sp
+When you set the PCRE_UTF32 flag, the strings of 32-bit data units that are
+passed as patterns and subjects are (by default) checked for validity on entry
+to the relevant functions.  This check allows only values in the range U+0
+to U+10FFFF, excluding the surrogate area U+D800 to U+DFFF.
+.P
+If an invalid UTF-32 string is passed to PCRE, an error return is given. At
+compile time, the only additional information is the offset to the first data
+unit of the failing character. The run-time functions \fBpcre32_exec()\fP and
+\fBpcre32_dfa_exec()\fP also pass back this information, as well as a more
+detailed reason code if the caller has provided memory in which to do this.
+.P
+In some situations, you may already know that your strings are valid, and
+therefore want to skip these checks in order to improve performance. If you set
+the PCRE_NO_UTF32_CHECK flag at compile time or at run time, PCRE assumes that
+the pattern or subject it is given (respectively) contains only valid UTF-32
+sequences. In this case, it does not diagnose an invalid UTF-32 string.
+However, if an invalid string is passed, the result is undefined.
+.
+.
+.SS "General comments about UTF modes"
+.rs
+.sp
+1. Codepoints less than 256 can be specified in patterns by either braced or
+unbraced hexadecimal escape sequences (for example, \ex{b3} or \exb3). Larger
+values have to use braced sequences.
+.P
+2. Octal numbers up to \e777 are recognized, and in UTF-8 mode they match
+two-byte characters for values greater than \e177.
+.P
+3. Repeat quantifiers apply to complete UTF characters, not to individual
+data units, for example: \ex{100}{3}.
+.P
+4. The dot metacharacter matches one UTF character instead of a single data
+unit.
+.P
+5. The escape sequence \eC can be used to match a single byte in UTF-8 mode, or
+a single 16-bit data unit in UTF-16 mode, or a single 32-bit data unit in
+UTF-32 mode, but its use can lead to some strange effects because it breaks up
+multi-unit characters (see the description of \eC in the
+.\" HREF
+\fBpcrepattern\fP
+.\"
+documentation). The use of \eC is not supported in the alternative matching
+function \fBpcre[16|32]_dfa_exec()\fP, nor is it supported in UTF mode by the
+JIT optimization of \fBpcre[16|32]_exec()\fP. If JIT optimization is requested
+for a UTF pattern that contains \eC, it will not succeed, and so the matching
+will be carried out by the normal interpretive function.
+.P
+6. The character escapes \eb, \eB, \ed, \eD, \es, \eS, \ew, and \eW correctly
+test characters of any code value, but, by default, the characters that PCRE
+recognizes as digits, spaces, or word characters remain the same set as in
+non-UTF mode, all with values less than 256. This remains true even when PCRE
+is built to include Unicode property support, because to do otherwise would
+slow down PCRE in many common cases. Note in particular that this applies to
+\eb and \eB, because they are defined in terms of \ew and \eW. If you really
+want to test for a wider sense of, say, "digit", you can use explicit Unicode
+property tests such as \ep{Nd}. Alternatively, if you set the PCRE_UCP option,
+the way that the character escapes work is changed so that Unicode properties
+are used to determine which characters match. There are more details in the
+section on
+.\" HTML <a href="pcrepattern.html#genericchartypes">
+.\" </a>
+generic character types
+.\"
+in the
+.\" HREF
+\fBpcrepattern\fP
+.\"
+documentation.
+.P
+7. Similarly, characters that match the POSIX named character classes are all
+low-valued characters, unless the PCRE_UCP option is set.
+.P
+8. However, the horizontal and vertical white space matching escapes (\eh, \eH,
+\ev, and \eV) do match all the appropriate Unicode characters, whether or not
+PCRE_UCP is set.
+.P
+9. Case-insensitive matching applies only to characters whose values are less
+than 128, unless PCRE is built with Unicode property support. A few Unicode
+characters such as Greek sigma have more than two codepoints that are
+case-equivalent. Up to and including PCRE release 8.31, only one-to-one case
+mappings were supported, but later releases (with Unicode property support) do
+treat as case-equivalent all versions of characters such as Greek sigma.
+.
+.
+.SH AUTHOR
+.rs
+.sp
+.nf
+Philip Hazel
+University Computing Service
+Cambridge CB2 3QH, England.
+.fi
+.
+.
+.SH REVISION
+.rs
+.sp
+.nf
+Last updated: 27 February 2013
+Copyright (c) 1997-2013 University of Cambridge.
+.fi
diff --git a/libs/Pcre16/docs/doc/perltest.txt b/libs/Pcre16/docs/doc/perltest.txt
new file mode 100644
index 0000000000..bb1a52a48e
--- /dev/null
+++ b/libs/Pcre16/docs/doc/perltest.txt
@@ -0,0 +1,42 @@
+The perltest program
+--------------------
+
+The perltest.pl script tests Perl's regular expressions; it has the same
+specification as pcretest, and so can be given identical input, except that
+input patterns can be followed only by Perl's lower case modifiers and certain
+other pcretest modifiers that are either handled or ignored:
+
+  /+   recognized and handled by perltest
+  /++  the second + is ignored
+  /8   recognized and handled by perltest
+  /J   ignored
+  /K   ignored
+  /W   ignored
+  /S   ignored
+  /SS  ignored
+  /Y   ignored
+
+The pcretest \Y escape in data lines is removed before matching. The data lines
+are processed as Perl double-quoted strings, so if they contain " $ or @
+characters, these have to be escaped. For this reason, all such characters in
+the Perl-compatible testinput1 file are escaped so that they can be used for
+perltest as well as for pcretest. The special upper case pattern modifiers such
+as /A that pcretest recognizes, and its special data line escapes, are not used
+in the Perl-compatible test file. The output should be identical, apart from
+the initial identifying banner.
+
+The perltest.pl script can also test UTF-8 features. It recognizes the special
+modifier /8 that pcretest uses to invoke UTF-8 functionality. The testinput4
+and testinput6 files can be fed to perltest to run compatible UTF-8 tests.
+However, it is necessary to add "use utf8; require Encode" to the script to
+make this work correctly. I have not managed to find a way to handle this
+automatically.
+
+The other testinput files are not suitable for feeding to perltest.pl, since
+they make use of the special upper case modifiers and escapes that pcretest
+uses to test certain features of PCRE. Some of these files also contain
+malformed regular expressions, in order to check that PCRE diagnoses them
+correctly.
+
+Philip Hazel
+January 2012