I had a need to test multicast between different points on our network, so I wrote some Perl. The server runs on a stable box (a server, go figure) and the client runs on a laptop I can move around. There is also a thin Windows client.

NOTE: On Linux/UNIX if you're not using your default interface for multicast, you'll need to do route add -net 224.0.0.0 netmask 240.0.0.0 dev eth1. Doing ping -t 1 -c 2 224.0.0.1 should return a list of multicasting clients on the network.

Contents 1 Server 2 Client 2.1 Perl 2.2 Windows

Server

The IO::Socket::Multicast module isn't standard, so you'll need to cpan it. Also, this requires IO::Interface if you want to use the mcast_if function.

#!/usr/bin/perl 

use IO::Socket::Multicast;
use strict;

$|=1;

my $MTESTADDRESS = "226.1.2.3";
my $MTESTPORT = "2010";

my $msock=IO::Socket::Multicast->new(Proto=>'udp',PeerAddr=>"$MTESTADDRESS:$MTESTPORT",ReuseAddr=>1);
$msock->mcast_if("eth0");

while(1) {
	my $time=localtime(time);
	$msock->mcast_send($time,"$MTESTADDRESS:$MTESTPORT") || die "$!\n";
	print ".";
	sleep(10);
} 

Client

Perl

#!/usr/bin/perl 

use IO::Socket::Multicast;
use strict;

my $MTESTADDRESS = "226.1.2.3";
my $MTESTPORT = "2010";

my $msock=IO::Socket::Multicast->new(Proto=>'udp',LocalPort=>"$MTESTPORT",ReuseAddr=>1);
$msock->mcast_add($MTESTADDRESS,"eth0") || die "Could not join $MTESTADDRESS on $MTESTPORT\n";

while(1) {
	my $buf;
	$msock->recv($buf,1024);
	print ".$buf\n";
}

Windows

Unfortunately, there's a non-standard DLL and a few OCXs that are needed to make the Windows version work.

Grab the binary here.