I say unto you the words of Stein The Wise:

($a,$b,$c,$d)      = split /\./, '18.157.0.125';
$packed_ip_address = pack 'C4', $a, $b, $c, $d;

($a,$b,$c,$d)      = unpack 'C4',$packed_ip_address;
$dotted_ip_address = join '.', $a,$b,$c,$d;
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Transcribed reverently from page 69 of Network Programming with Perl, a very worthy tome.