flex-old

Old version of the fast lexical analyzer generator
flex is a tool for generating scanners: programs which recognize lexical
patterns in text. This is the old 2.5.4a version, which is no longer
being developed. You should normally choose flex, unless you have
legacy lexer files that do not work with a modern flex.
.
This product includes software developed by the University of California,
Berkeley and its contributors. The upstream source code can be found at
http://flex.sourceforge.net/