Listing Multicast group memberships

In Windows XP:

C:\>netsh interface ip show joins


Interface Addr   Multicast Group
---------------  ---------------
172.17.17.223    224.0.0.1
172.17.17.223    239.255.255.250

In Solaris and other UNIXes:


$ netstat -gn
IPv6/IPv4 Group Memberships
Interface       RefCnt Group
--------------- ------ ---------------------
lo              1      224.0.0.1
eth0            1      224.0.0.1
lo              1      ff02::1
eth0            1      ff02::1:ff09:ac30
eth0            1      ff02::1