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<!-- manual page source format generated by PolyglotMan v3.2, -->
<!-- available at http://polyglotman.sourceforge.net/ -->
<html>
<head>
<title>PCRE(3) manual page</title>
</head>
<body bgcolor='white'>
<a href='#toc'>Table of Contents</a><p>
<h2><a name='sect0' href='#toc0'>Name</a></h2>
PCRE - Perl-compatible regular expressions
<h2><a name='sect1' href='#toc1'>Pcre Sample Program</a></h2>
<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. <p>
The program 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 system, you should be able to compile the demonstration
program using this command: <p>
gcc -o pcredemo pcredemo.c -lpcre<br>
<p>
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: <p>
gcc -o pcredemo -I/usr/local/include pcredemo.c \<br>
-L/usr/local/lib -lpcre<br>
<p>
Once you have compiled the demonstration program, you can run simple tests
like this: <p>
./pcredemo ’cat|dog’ ’the cat sat on the mat’<br>
./pcredemo -g ’cat|dog’ ’the dog sat on the cat’<br>
<p>
Note that there is a much more comprehensive test program, called <b>pcretest</b>,
which supports many more facilities for testing regular expressions and
the PCRE library. The <b>pcredemo</b> program is provided as a simple coding example.
<p>
On some operating systems (e.g. Solaris), when PCRE is not installed in the
standard library directory, you may get an error like this when you try
to run <b>pcredemo</b>: <p>
ld.so.1: a.out: fatal: libpcre.so.0: open failed: No such
file or directory<br>
<p>
This is caused by the way shared library support works on those systems.
You need to add <p>
-R/usr/local/lib<br>
<p>
(for example) to the compile command to get round this problem. <p>
Last updated:
09 September 2004 <br>
Copyright (c) 1997-2004 University of Cambridge. <p>
<hr><p>
<a name='toc'><b>Table of Contents</b></a><p>
<ul>
<li><a name='toc0' href='#sect0'>Name</a></li>
<li><a name='toc1' href='#sect1'>Pcre Sample Program</a></li>
</ul>
</body>
</html>
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