Incompatible struct in_pktinfo (kern/48166)

[Tom Ivar Helbekkmo <tih%hamartun.priv.no@localhost>]

I decided to see exactly what changes it would take to get the latest
PowerDNS suite to compile under NetBSD-current, which turns out to be
"not a lot".  One of the problems, though, is at our end, and concerns
more than just PowerDNS.  It has to do with how a UDP service on a
multi-homed machine gets its responses properly sent out *from* the
correct address using the IP_PKTINFO socket option.  This was addressed
in PR#48166, which is more than four years old, but still open.

Before I create a ticket for the PowerDNS folks with the set of patches
I'd like them to apply to their code, to make it build and run on NetBSD
"out of the box", I thought I'd see if maybe this one could be handled
at our end, as it seems to me it ought to be.

There's a nice summary of how it's used in the top answer here:
https://stackoverflow.com/questions/3062205/setting-the-source-ip-for-a-udp-socket

-tih
-- 
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