Lo, I have a snippet of fixed code, ie I can't change it. All that I have control over is the regex that is passed to it.. 
    open FH, "< $file";
    while (<FH>) {
        # for each regex
        for my $re ( keys %{ $compiled->{'rx'} } ) {
            $compiled->{'rx'}{$re}++ if /$re/;
        }
    }
    close FH;

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I have some DOS (ie each line ends in \r\n) files that are look like (this is run on linux) 
foo
bar
"99","END"

[download]
or 
"99","END"

[download]

ie all files contain "99","END" but some contain other lines before it.

My problem is that I need to positively match the files containing _only_ the "99","END"

ie in the example files above, I have a regex that would match "foo", this would find the first file, however, what regex would find the second file? One of END wouldn't work because that would find the foo file.

The only idea I have is to embed perl in a regex and somehow test that if we have END and are on the first iteration of the while, it matches.

Any other ideas appreciated...

John

In reply to using a regex to determine if a string is the start of the FILE by ftumsh

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