And just for variety (TIMTOWTDI, after all), I first thought of using pack: 
sub pad{
   my ($string, $length) = @_;
   return (length($string) < $length ? pack("A$length", $string) : $st
+ring);
}

[download]
... although after reading all the responses, I agree that sprintf is the best way to go.

In reply to Re: Generating standard length strings by crashtest
in thread Generating standard length strings by kage-yojimbo

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