#!/usr/bin/perl
# file cidr.pl
$m=pack B32,pop=~'/'x$';printf"$` network %vd broadcast %vd netmask %vd\n",($z=eval$`)&$m,$z|~$m,$m

##</code><code>##

shmem [qwurx] ~ > cidr.pl 172.16.242.150/27
172.16.242.150 network 172.16.242.128 broadcast 172.16.242.159 netmask 255.255.255.224