| # PCRE2 - Perl-Compatible Regular Expressions |
| |
| The PCRE2 library is a set of C functions that implement regular expression |
| pattern matching using the same syntax and semantics as Perl 5. PCRE2 has its |
| own native API, as well as a set of wrapper functions that correspond to the |
| POSIX regular expression API. The PCRE2 library is free, even for building |
| proprietary software. It comes in three forms, for processing 8-bit, 16-bit, |
| or 32-bit code units, in either literal or UTF encoding. |
| |
| PCRE2 was first released in 2015 to replace the API in the original PCRE |
| library, which is now obsolete and no longer maintained. As well as a more |
| flexible API, the code of PCRE2 has been much improved since the fork. |
| |
| ## Download |
| |
| As well as downloading from the |
| [GitHub site](https://github.com/PCRE2Project/pcre2), you can download PCRE2 |
| or the older, unmaintained PCRE1 library from an |
| [*unofficial* mirror](https://sourceforge.net/projects/pcre/files/) at SourceForge. |
| |
| You can check out the PCRE2 source code via Git or Subversion: |
| |
| git clone https://github.com/PCRE2Project/pcre2.git |
| svn co https://github.com/PCRE2Project/pcre2.git |
| |
| ## Contributed Ports |
| |
| If you just need the command-line PCRE2 tools on Windows, precompiled binary |
| versions are available at this |
| [Rexegg page](http://www.rexegg.com/pcregrep-pcretest.html). |
| |
| A PCRE2 port for z/OS, a mainframe operating system which uses EBCDIC as its |
| default character encoding, can be found at |
| [http://www.cbttape.org](http://www.cbttape.org/) (File 939). |
| |
| ## Documentation |
| |
| You can read the PCRE2 documentation |
| [here](https://PCRE2Project.github.io/pcre2/doc/html/index.html). |
| |
| Comparisons to Perl's regular expression semantics can be found in the |
| community authored Wikipedia entry for PCRE. |
| |
| There is a curated summary of changes for each PCRE release, copies of |
| documentation from older releases, and other useful information from the third |
| party authored |
| [RexEgg PCRE Documentation and Change Log page](http://www.rexegg.com/pcre-documentation.html). |
| |
| ## Contact |
| |
| To report a problem with the PCRE2 library, or to make a feature request, please |
| use the PCRE2 GitHub issues tracker. There is a mailing list for discussion of |
| PCRE2 issues and development at [email protected], which is where any |
| announcements will be made. You can browse the |
| [list archives](https://groups.google.com/g/pcre2-dev). |
| |
