Nothing immediately jumps out at me. Beware of carriage returns some web browsers send in textareas. You might run a transliteration on the value of the "filecontents" field:

$INPUT{filecontents} =~ tr/\r//d;

Otherwise, perhaps the best you can do is to add an else clause: 

if ($INPUT{account} eq $account_line) {
    # print ban message and such
} else {
    warn "($INPUT{account}) didn't match <$account_line>\n";
}

[download]
Wrapping delimiters around variables lets you see if any whitespace has sneaked through.

(Side note: I'd use a tied hash instead of a flat file. It's much more efficient.)

In reply to Re: Need help reading and writing to a file. by chromatic
in thread Need help reading and writing to a file. by PhantomStar

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