Multihomed UDP server

[Bjoern A. Zeeb]

On Mon, 19 Jan 2004, Poul-Henning Kamp wrote:

> In message <200401192002.i0JK2SJZ058752 at khavrinen.lcs.mit.edu>, Garrett Wollman
>  writes:
> ><<On Mon, 19 Jan 2004 12:58:00 +0100, "Poul-Henning Kamp" <phk at phk.freebsd.dk> said:
> >
> >> I'm considering ways to make sendmsg(2)/recvmsg(2) DTRT, and my
> >> current candidate is give them a flag bit which says "msg_name has
> >> both addresses".
> >
> >Um, they already do the right thing.  That's what the IP_RECVDESTADDR

actually it is IP_RECVDSTADDR (no E).

> >option (and its dual whose name I forget right now) is all about.
>
> Yeah, I found that out.  Now, where on the earth is that documented ?

You mean for FreeBSD or in ISBN 0-13-490012-X ?

For FreeBSD it is man 4 ip:

--- cite ---
     If the IP_RECVDSTADDR option is enabled on a SOCK_DGRAM socket, the
     recvmsg(2) call will return the destination IP address for a UDP data-
     gram.  The msg_control field in the msghdr structure points to a buffer
     that contains a cmsghdr structure followed by the IP address.  The
     cmsghdr fields have the following values:
--- cite ---

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Bjoern A. Zeeb				bzeeb at Zabbadoz dot NeT
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