re -- SooSet

fast lexical analyzer generator

BSD- lexical- parser- regular expression- re

The PCRE library is a set of functions that implement regular expression pattern matching using the same syntax and semantics as Perl 5

BSD - More version- regular expression- re

sed 4.2

Sed (streams editor) isn't really a true text editor or text processor. Instead, it is used to filter text, i.e., it takes text input and performs some operation (or set of operations) on it and outputs the modified text.

GPL- text- editor- regular expression- re