| Name | Last modified | Size | Description | |
|---|---|---|---|---|
| Parent Directory | - | |||
| __bug_table | 2026-10-23 15:20 | 19 | ||
| __dyndbg | 2026-10-23 15:20 | 19 | ||
| __jump_table | 2026-10-23 15:20 | 19 | ||
| __mcount_loc | 2026-10-23 15:20 | 19 | ||
| __patchable_function..> | 2026-10-23 15:20 | 19 | ||
Return to the PCRE2 index page.
This page is part of the PCRE2 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.
PCRE2 SAMPLE PROGRAM
A simple, complete demonstration program to get you started with using PCRE2 is supplied in the file pcre2demo.c in the src directory in the PCRE2 distribution. A listing of this program is given in the pcre2demo documentation. If you do not have a copy of the PCRE2 distribution, you can save this listing to re-create the contents of pcre2demo.c.
The demonstration program compiles the regular expression that is its first argument, and matches it against the subject string in its second argument. No PCRE2 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.
The code in pcre2demo.c is an 8-bit program that uses the PCRE2 8-bit library. It handles strings and characters that are stored in 8-bit code units. By default, one character corresponds to one code unit, but if the pattern starts with "(*UTF)", both it and the subject are treated as UTF-8 strings, where characters may occupy multiple code units.
If PCRE2 is installed in the standard include and library directories for your operating system, you should be able to compile the demonstration program using a command like this:
cc -o pcre2demo pcre2demo.c -lpcre2-8I