When I do this, I get s length of 24 for $atr: 
$str = 'abcde';
$str .= "\0" x (24 - length $str);
print length $str;
print "\n";

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How are you using the string? Printing something with null bytes might not do what you expect and probably won't do what you want.

In reply to Re: perl null padding by mr_mischief
in thread perl null padding by m.y

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