Re: [Qemu-devel] Re: [PATCH] add a command line option to specify the interface to send multicast packets on

[Mike Ryan]

On Tue, Nov 16, 2010 at 07:54:58PM +0200, Michael S. Tsirkin wrote:
>
> <snip>
>
> Let's let the user pass in the IP address? That would solve the
> portability issue. Further, we could be doing IPv6, right?
> So you'd need IPV6_MULTICAST_IF?
> Also - you might also want to control
> IP_MULTICAST_LOOP/IPV6_MULTICAST_LOOP?

IP address seems like a good alternative and does indeed get rid of the
messy platform-specific bits.

The multicast code all assumes IPv4. For instance, it uses v4-only
parse_host_port to get the multicast destination address. Given that,
I'm not going to bother shoehorning in IPV6_MULTICAST_IF.