Well, $octet is uninitialized because: 
$octet ||= $_ if /($hacklist =~ m~((\d{1,3}\.){3}\d{1,3})~)/;

[download]
never matches anything.

It doesn't match anything since $hacklist is set to "hack.txt" early on in your script: 

my $hacklist = "hack.txt";

[download]
Perhaps you meant $_=~ rather than $hacklist =~ ?

In reply to Re: Octet Regex by kschwab
in thread Octet Regex by amearse

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