# clear separators to obtain a hex string
    $mac =~ s/://g;
  # convert hex string into a dec number
    my $dec = hex($mac);
  # revert into a hex string 
    $mac = sprintf("%012x", $dec+$add);
[download]

I don't see error here. I think it's used by context...

  # convert hex string into a dec number
    my $dec = hex($mac);
  # revert into a hex string 
    $mac = sprintf("%012x", $dec+$add);
[download]

My argument is with the word "dec" there. It's not decimal. It's just a number. In fact, it's more binary than it is decimal. {grin}

The "hex" operator interprets a hex string or an octal string, converting them to a number. A number is an abstraction, without a numeric base, until it gets converted to a string again.

Thus, you never really have a "decimal" number there. Just a number. Because you never printed it out.

-- Randal L. Schwartz, Perl hacker
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