I'd like to help, but that doesn't even compile. Is that the problem you're asking about, or do you have some code that does compile, but that doesn't do what you want it to do?

From what I can decipher from the code posted, I really think you're working too hard at this. If the file is not "huge", just use Tie::File so you don't have to keep worrying about seeking through the file manually. And if the file is huge, use DBI with DBD:SQLite

Tie::File is part of the core Perl distribution, so you should have it available, and while its performance isn't excellent, it is well debugged, and saves you from having to implement your own flat-file-database solution.