I'll raise you one and reveal the wonderful $.: 
while (<>) {
    printf("line %2d: %s", $., $_);
    $res = $1 if /^Referer: (.*)$/;
}

[download]
You can get rid of the open if you want to open the file specified as the first argument. $. keeps track of the current line number. (You ought to check your open call for success, too.)

In reply to RE: Re: Parsing a file one line at a time by chromatic
in thread Parsing a file one line at a time by cburns

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