Hello soulbleach, and welcome to the Monastery!

Note that the regex in this line:

my @strings = $line =~ m/(RC[0-9][0-9][0-9][0-9])/;
[download]

contains only a single capture, so if the match succeeds @strings will contain only one element. Did you intend more than one capture per $line? If so, you need to add a /g modifier to the regex:

my @strings = $line =~ m/(RC[0-9]{4})/g;
[download]

Update: See “Global matching” in perlretut. (Also shortened regex: see “Quantifiers” in Regular Expressions.)

But without sample input data and desired output, it’s hard to know what you’re trying to do.

Anyway, hope that helps,