Does this fit the bill?

use strict;
use warnings;
use Net::Netmask;

while (<>) {
  chomp;
  s/;/:/;
  my $block = new Net::Netmask($_);
  if (not $block) {
    warn "Bad CIDR specification";
    next;
  }
  my @ip    = $block->enumerate();

  # Remove the network and gateway addresses.
  shift(@ip);
  shift(@ip);

  # Remove the broadcast address.
  pop(@ip);

  for my $ip (@ip) {
    print $ip, "\n";
  }
}
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--jwest

-><- -><- -><- -><- -><-
All things are Perfect
    To every last Flaw
    And bound in accord
         With Eris's Law
 - HBT; The Book of Advice, 1:7