I had a similar problem in the past with variables such as: $n = $filenameB if ($n = $filenameA);

No wonder you are having problems with this, two errors in the same line :). First of all you are doing an assignment in the if-condition so this should be '==' instead of '='. And second '==' only works for numbers which is probably not what you want ($filename !!). You should use 'eq' instead. $n = $filenameB if ($n eq $filenameA);

-- Hofmator