NAME | PCRE SAMPLE PROGRAM | AUTHOR | REVISION | COLOPHON

PCRESAMPLE(3)             Library Functions Manual             PCRESAMPLE(3)

NAME         top

       PCRE - Perl-compatible regular expressions

PCRE SAMPLE PROGRAM         top


       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
       possibility 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
       demonstration 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_malloc() 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
       systems. You need to add

         -R/usr/local/lib

       (for example) to the compile command to get round this problem.

AUTHOR         top


       Philip Hazel
       University Computing Service
       Cambridge CB2 3QH, England.

REVISION         top


       Last updated: 10 January 2012
       Copyright (c) 1997-2012 University of Cambridge.

COLOPHON         top

       This page is part of the PCRE (Perl Compatible Regular Expressions)
       project.  Information about the project can be found at 
       ⟨http://www.pcre.org/⟩.  If you have a bug report for this manual
       page, see ⟨http://bugs.exim.org/enter_bug.cgi?product=PCRE⟩.  This
       page was obtained from the tarball pcre-8.41.tar.gz fetched from 
       ⟨ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre/⟩ on
       2017-09-15.  If you discover any rendering problems in this HTML ver‐
       sion of the page, or you believe there is a better or more up-to-date
       source for the page, or you have corrections or improvements to the
       information in this COLOPHON (which is not part of the original man‐
       ual page), send a mail to man-pages@man7.org

PCRE 8.30                      10 January 2012                 PCRESAMPLE(3)

Pages that refer to this page: pcreapi(3)