Projects / PCRE


The PCRE library is a set of functions that implement regular expression pattern matching using the same syntax and semantics as Perl 5, with just a few differences. PCRE is used by many programs, including Exim, Postfix, and PHP.

Operating Systems

Recent releases

  •  04 Apr 2014 13:51

    Release Notes: There have been performance improvements for classes containing non-ASCII characters, and the "auto-possessification" feature has been extended. Other minor improvements have been implemented, and bugs fixed. There is a new callout feature to enable applications to do detailed stack checks at compile time, to avoid running out of stack for deeply-nested parentheses. The JIT compiler has been extended with experimental support for ARM-64, MIPS-64, and PPC-LE.

    •  15 Dec 2013 17:19

      Release Notes: Performance has been improved by extending the "auto-possessification" feature. Backreferences to named subpatterns now check all with the same name; this and other changes improve compatibility with Perl. A number of bugs have been mended.

      •  28 May 2013 09:27

        Release Notes: The Just-In-Time compiler (JIT) now supports all pattern features, including callouts and the backtracking verbs. In addition, some bugs are fixed and there are minor performance enhancements.

        •  30 Nov 2012 11:17

          Release Notes: Support for 32-bit characters strings and UTF-32 has been added. Unicode compatibility has been improved for \X (it now matches extended grapheme clusters) and for characters such as Greek sigma that have more than one "other case". The Unicode tables are updated to 6.2.0. Matching using the JIT compiler has been sped up in some cases. There are some extensions to pcregrep and, as always, bugs have been fixed.

          •  06 Jul 2012 10:18

            Release Notes: The changes for this release are mainly bugfixes, though there are one or two small additional features.

            Recent comments

            11 Jan 2005 04:52 mr700

            what about the recursion bug affecting php (probably all apps using pcre)

            Are bugs like RH bug #133891 (, PHP bug #24460 (, PHP bug #26171 ( and PHP bug #27070 ( going to be addressed?

            In short: with some match patterns and data from 1000 bytes pcre causes php (and probably others) to crash. The problem seems to be that "PCRE uses recursion to handle subpatterns and indefinite repetition" (from PHP bug #24460 (

            16 Sep 2004 10:51 aldem

            WOW! Partial macthing rulez :)
            Finally... You did it.. It took some time, though... :)

            Many thanks :)


            Project Spotlight


            A Fluent OpenStack client API for Java.


            Project Spotlight

            TurnKey TWiki Appliance

            A TWiki appliance that is easy to use and lightweight.