Before you present your code check that it at least runs, or ensure that you have copied and pasted (not retyped) the code that you want us to check. Your current code has obvious syntax errors that you would have been told about if you tried to run it such as the missing ')' in the chomp line and the fact that you use $filename before declaring it or giving it a value.

Syntax errors aside, what do you expect the code to do and how does it achieve that? If you can't explain what you expect your code to do there's a pretty good chance the Perl interpreter is going to have a hard time of it too!

Tell us what input is expected (give a little sample) and what output you expect (give a little sample) and show us what you actually get. If you can avoid needing to hand feed the script while it's running that helps too. See I know what I mean. Why don't you?.