Windows XP
To see multicast group memberships in Windows XP, you can use netsh :
U:>netsh interface ip show joins Interface Addr Multicast Group --------------- --------------- 192.168.139.1 224.0.0.1 192.168.137.1 224.0.0.1 192.168.136.1 224.0.0.1
Solaris (and probably other Unixen as well)
In Solaris, the netstat command can be used :
$ netstat -g Group Memberships: IPv4 Interface Group RefCnt --------- -------------------- ------ lo0 224.0.0.1 1 eri0 224.0.0.1 1 $