[gini] getting multicast listener to work on UMLs

[Alexis Malozemoff]

Here's a message from last year's mailing list which you may find
useful to avoid the "setsockopt: no such device" error when running
listener.c:

please do

route -n

on the UML from where you were running the listener. you might notice that
it
does not have any routes to handle the class D address that is being opened
by the
listener.c program.

run the following command to add a default route pointing to the default
gateway
for that particular machine.

route add default gw nearest_router's_IP_address

run the
route -n
command and make sure that you have a default route installed.
listener should work now.
also, as handout pointed out.. please change the IGMP version as well.