In message <199610220914.JAA29938@whydos.lkg.dec.com> you write:
>The following internet draft contains a slightly different way of doing
>that for IPv6.  Add a correspond mode for Ipv4 should be trivial.

The reason I am using a sockaddr instead of just 2 bytes to store the
ifindex is because I expect to create a SunOS version of this, and
SunOS doesn't have ifindexes so I was going to pass the address of
the interface.

>(get both destination address and the interface index (no sockaddr_dl)
>in one ancillary data message).

Well, BSD 4.4 already has IP_RECVDSTADDR, which I don't want to change, so
adding another way to get the destination address seems redundant.  Plus,
when using raw sockets, you get a copy of the IP header anyway, so getting
the destination address there is just extraneous.

  Bill