Revisiting UDP support (for trunk)

[Issac Goldstand]

Hi all,
 I've been quietly hacking away at getting UDP support working with 
trunk (prefork/unix only, for starters).  While I had a decent amount of 
success, I eventually got stuck: my original naive  plan had been to 
poll, recvfrom (to get peer address), dup the socket, connect the dup-ed 
socket and close the dup-ed socket after processing a single request (as 
defined by the connection/protocol handlers).  The hope was that since 
we never connected the original socket, it would still do something 
useful.  To make a long story short, I found that it wasn't doing 
anything of the sort.

Before I launch into a new tactic, I wanted to see if someone has a 
better idea than me - the only thing that pops into my mind is moving 
some sort of pointers to the UDP listeners into the scoreboard (or some 
other R/W shared area) and simply letting the children/workers lock used 
sockets (so other children/workers don't poll it), and completely 
replace them after they're used.  There are a lot of disadvantages to 
doing that, I think, but I can't dream up a smarter solution.  Anyone 
have any ideas?

 Issac