3 PCRE - Perl-compatible regular expressions
4 .SH "PCRE SAMPLE PROGRAM"
7 A simple, complete demonstration program, to get you started with using PCRE,
8 is supplied in the file \fIpcredemo.c\fP in the PCRE distribution.
10 The program compiles the regular expression that is its first argument, and
11 matches it against the subject string in its second argument. No PCRE options
12 are set, and default character tables are used. If matching succeeds, the
13 program outputs the portion of the subject that matched, together with the
14 contents of any captured substrings.
16 If the -g option is given on the command line, the program then goes on to
17 check for further matches of the same regular expression in the same subject
18 string. The logic is a little bit tricky because of the possibility of matching
19 an empty string. Comments in the code explain what is going on.
21 If PCRE is installed in the standard include and library directories for your
22 system, you should be able to compile the demonstration program using this
25 gcc -o pcredemo pcredemo.c -lpcre
27 If PCRE is installed elsewhere, you may need to add additional options to the
28 command line. For example, on a Unix-like system that has PCRE installed in
29 \fI/usr/local\fP, you can compile the demonstration program using a command
33 gcc -o pcredemo -I/usr/local/include pcredemo.c \e
34 -L/usr/local/lib -lpcre
36 Once you have compiled the demonstration program, you can run simple tests like
39 ./pcredemo 'cat|dog' 'the cat sat on the mat'
40 ./pcredemo -g 'cat|dog' 'the dog sat on the cat'
42 Note that there is a much more comprehensive test program, called
46 which supports many more facilities for testing regular expressions and the
47 PCRE library. The \fBpcredemo\fP program is provided as a simple coding
50 On some operating systems (e.g. Solaris), when PCRE is not installed in the
51 standard library directory, you may get an error like this when you try to run
54 ld.so.1: a.out: fatal: libpcre.so.0: open failed: No such file or directory
56 This is caused by the way shared library support works on those systems. You
61 (for example) to the compile command to get round this problem.
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78 Last updated: 23 January 2008
79 Copyright (c) 1997-2008 University of Cambridge.
