Something like the following ought to do it: 
my @ids;

while (<LOG>) {
    if (/id\+(\d+)/) {
        push @ids, $1;
    }
}

[download]
That's not substantially different from what you have, so you should probably post the code you're using so we might have more detail.

In reply to Re: Logfile parsing (Moved from Q&A) by chromatic
in thread Logfile parsing (Moved from Q&A) by Russ

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