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Since your title focuses on regular expressions, I'll assume that's where your issue lies. If we assume all lines of interest consist of 'pass' followed by whitespace, a colon and your desired value which will be an integer, then the following code should be a useful template: 

use strict;
use warnings;

while (my $line = <DATA>) {
    if ($line =~ /^pass\s*\:(\d+)/) {
        print "$1\n";
    }
}

__DATA__
abcd
pass    :10
adlksfkldf
kkjfkdf  :112

[download]

See Extracting matches for more information on extracting information. If this code is unclear, I'd be happy to provide additional clarification.

In reply to Re: Regex doubts by kennethk
in thread Regex doubts by Anonymous Monk

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