In fairness to the OP, the code posted does run without strictures and warnings; the undefined variable is irrelevant to the problem, and when warnings aren't enabled, the "print" will just silently concatenate that undefined variable into the output.

Now it's entirely possible that without strictures and warnings, the OP has misspelled a variable, and that since the misspelling isn't being caught by 'strict', either the target string or the 'pattern' variable doesn't contain what he expects.

But the code he demonstrated is pretty clearly part of something larger (probably a wanted() routine passed into File::Find). So we don't know that strict and warnings aren't being used in the script.

And now in fairness to you (Loops): The OP's code snippet doesn't demonstrate the problem, and consequently is next to useless in helping us to help him to diagnose his problem. It would be far more useful to us in our quest to help him had he provided a self-contained compilable code snippet that actually runs and actually demonstrates the problem. I have a feeling, though, that if he took the time to boil this down to a test case that he could demonstrate to us, he himself would discover the source of the problem along the way, and we wouldn't have anything to answer. ;)