The Parse::FixedLength module facilitates the process of breaking a
string into its fixed-length components. Sure, it's a glorified (and in
some ways more limited) substitute for the perl functions pack and
unpack, but it's the author's belief that this module helps in the
maintainability of working with fixed length formats as the number of
fields in a format grows.

WWW: http://search.cpan.org/dist/Parse-FixedLength/