I'm not sure that I fully understand your question, but would point out that the pcre (Perl Compatible Regular Expressions) C library is used as part of PHP for preg_match(), preg_replace(). (PHP aping it's betters again ;-))

pcre's are also used in applications such as the Postfix mail system. Part of my own anti-spam solution for my Postfix mail servers uses pcre's for message header and body checks. For reference, here are my current bodychecks and headerchecks files. (For anyone thinking that my regex syntax is weird, I've done them like this so that I can read them easily.)

In reply to Re: Perl regex in real life by smiffy
in thread Perl regex in real life by RezaRob

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