Others have commented on your code. I just wanted to mention something about the comments in your code.

It's much better to make a block comment before a section to describe what the section is doing, and leave out all the single-line comments that are obvious from the code. For instance, "#Path to perl interpreter" and "#Open the file links.txt for appending" are obvious from the code and should be eliminated. They only clutter up the code itself, and make it more difficult to follow the flow of the program.

The Practice of Programming by Kernigan & Pike has a chapter that goes over basic coding style, and is an excellent guide for good commenting.