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+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.