"Pirabhu Raman" <pirabhur@ufl.edu> writes:
> mreq.imr_multiaddr.s_addr = sock_addr.sin_addr.s_addr;
> mreq.imr_address.s_addr = htonl(INADDR_ANY);

Set imr_address to something other than zero. You need to specify the
address of the interface on which you want to join this multicast
group -- using the local address for broadcast-type interfaces, and
the remote address for point-to-point interfaces.

--
James Carlson, IP Systems Group <james.d.carlson@sun.com>
Sun Microsystems / 1 Network Drive 71.234W Vox +1 781 442 2084
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