INADDR_ALLRTRS_GROUP
htonl(INADDR_ALLRTRS_GROUP),
m.imr_multiaddr.s_addr = htonl(INADDR_ALLRTRS_GROUP);
m.imr_multiaddr.s_addr = htonl(INADDR_ALLRTRS_GROUP);
(htonl(INADDR_ALLRTRS_GROUP)));
(INADDR_ALLRTRS_GROUP - INADDR_UNSPEC_GROUP));