UDP prototype » History » Revision 8
Revision 7 (Greg Burri, 07/01/2009 01:48 PM) → Revision 8/9 (Greg Burri, 07/01/2009 10:44 PM)
h1. UDP prototype h2. Goals * Make a program which will listen for multicast message. * It must be work between sub-networks (vlan). * It should be also able to send. User can type a message and all other peers will print it when it is sent. * Test it with some computers. h2. Qt and UDP multicast There is no support to UDP multicast in QT4.5 according this bug issue : http://www.qtsoftware.com/developer/task-tracker/index_html?method=entry&id=57952. Maybe it can be possible to use "setsockopt()":http://linux.die.net/man/2/setsockopt with _QAbstractSocket::socketDescriptor()_. See http://linux.die.net/man/7/ip and options for multicast like _IP_ADD_MEMBERSHIP_. h2. Broadcast An alternative is to use a broadcast address with _QHostAddress::Broadcast_. It will only work with IPv4. It's possible to use UDP multicast only with the low-level API. This solution is OS dependent and will not be accepted. For the moment the broadcast alternative will be used. h2. References * http://en.wikipedia.org/wiki/Multicast * http://tldp.org/HOWTO/Multicast-HOWTO-6.html (fr) http://www.ibiblio.org/pub/Linux/docs/HOWTO/translations/fr/html-1page/Multicast-HOWTO.html