Well, the problem is that the files are not really database files but files with an already given definition (for example, .ZIP archives, .MP3 files or in this special case, MacBinary files). I have good, working Pascal code that reads the information from these files, but I'd like to port that work to Perl to become more portable.

Perl would have the easy extensibility of a scripting language, but it has the problem of reading and parsing the record in the first place ...