To create a UDP socket suitable for sending outgoing multicast messages, call new() without arguments (or with Proto=>'udp'). It takes the same arguments as IO::Socket::INET, except that the Proto argument, rather than defaulting to 'tcp', will default to 'udp', which is more appropriate for multicasting. The new() method is the constructor for the IO::Socket::Multicast class. CONSTRUCTORS $socket = IO::Socket::Multicast->new() To activate or deactivate the looping back of multicast messages (in which a copy of the transmitted messages is received by the local machine), call mcast_loopback().

To set the number of hops (routers) that outgoing multicast messages will cross, call mcast_ttl(). Mcast_set() will set a default multicast destination for messages which you then send with mcast_send(). The mcast_set() and mcast_send() methods are provided as convenience functions. To send transmissions to a multicast group, you can use the standard send() method to send messages to the multicast group and port of your choice. Subsequent calls to the standard recv() method will now receive messages incoming messages transmitted to the subscribed groups using the selected port number. You will then subscribe one or more multicast groups using the mcast_add() method. To receive transmissions from a multicast group, you will use IO::Socket::Multicast->new() to create a UDP socket and bind it to a local network port. A program tunes in to a multicast group to receive transmissions to it, and tunes out when it no longer wishes to receive the transmissions. Messages sent to these addresses will be delivered to a potentially large number of machines that have registered their interest in receiving transmissions on these groups. These addresses do not correspond to individual machines, but to multicast groups. IP addresses in the range 224.0.0.0 and 239.255.255.255 are reserved for multicasting. Multicasting is designed for streaming multimedia applications and for conferencing systems in which one transmitting machines needs to distribute data to a large number of clients. This module requires IO::Interface version 0.94 or higher.

With this module (and an operating system that supports multicasting), you will be able to receive incoming multicast transmissions and generate your own outgoing multicast packets. The IO::Socket::Multicast module subclasses IO::Socket::INET to enable you to manipulate multicast groups. $s->mcast_send('hello again!') DESCRIPTION

# Set time to live on outgoing multicast packets My $s = IO::Socket::Multicast->new(LocalPort=>1100) # create a new UDP socket ready to read datagrams on port 1100 IO::Socket::Multicast - Send and receive multicast messages SYNOPSIS use IO::Socket::Multicast

Send wlisten multicast