Regex

Regex is an abbreviation of regular expression.

Regex is a C regular expression library written by Henry Spencer. Later versions support
the POSIX standardized regular expressions.

Regex is now found in various places:

Bundled with application such as Apache.
:Default regular expression implementation in BSD Unix.
:ftp://ftp.zoo.toronto.edu/pub/regex.shar - a shar archive, released by Henry Spencer in 1999.
:http://arglist.com/regex/ -- a repackaged version for Unix systems.
:Other sites around the Internet have ports or compiled code for other systems such as Microsoft Windows.
:Picnix is an example of a Microsoft Windows implementation that uses Henry Spencers Regex library
:Tcl includes a rewritten regular expression library by Henry Spencer.
:PHP can use RegEx with the preg_replace and preg_match functions.

The GNU project has in the past published a package named Regex: this code may now be in the GNU C Library.