#!/usr/bin/perl -w
# written by Schuyler Erle <schuyler@iconocla.st>

use IO::Socket;
use strict;

$ENV{PATH} = "$ENV{PATH}:/sbin:/usr/sbin";

my $ifconfig  = qx{ifconfig};
my @nets      = ($ifconfig =~ /\bBcast:\s*(\S+)/ios);
warn "found networks: @nets\n";

my $bcast = "";
$bcast = "-b" unless system("ping -c1 -b 127.0.0.0 2>&1 >/dev/null");
my $scan = qx{ping -c2 $bcast @nets 2>&1};
my @hosts = ($scan =~ /((?:\d{1,3}\.){3}\d{1,3})/gos);

warn "found ", scalar(@hosts), " hosts. scanning...\n"; 
for my $host (keys %{{@hosts}}) {
    my $sock = IO::Socket::INET->new(
	PeerAddr => $host,
	PeerPort => 9100,
        Timeout => 2,
	Proto => "tcp"
    );
    print "$host\n" if $sock;
}