I've just bastardized a version of the dhclient in the NetBSD-1.5_ALPHA2
tree to handle dynamic interface insertion and deletion.

I did that by listening to the kernel routing socket for IFANNOUNCE
messages, then gutting the "dispatch.c" module to permit adding
interfaces one-by-one, rather than the existing static scan.

Some change to the "protocol" eventloop mechanism and timer
callbacks were also needed, to allow removal of interfaces.

I've had this running on a laptop for several hours, popping and
inserting a WaveLan card over 50 times, to make sure there's no
fd leakage.

The patches still need significant cleanup, but I'm wondering if
there's anyone who would like to (a) test them, (b) review them, or
(c) help with reworking them to incorporate into the main ISC branch
(i.e., dhcpd-3.x rather than 2.x)?


Its way too late to get these into the NetBSD-1.5 release, but with
luck, something similar should appear in the 1.5.1 release.