events when (de)associating or when cable is (un)plugged

[Dirk-Willem van Gulik]

Looking for suggestions on a 'clean' and generic way to allow for
notifications when a 802.11 association is made or lost, or when
a ethernet cable is (un)plugged. I.e.akin to the events 'usbd(8) get
when you sit on /dev/usb. This is for 5.2.1 or beyond.

Any infrastructure which is already used I can leverage ?  (Right
now I do a dirty hack by letting the net80211 code twiddle
the INET address - which then causes a routing msg on a
socket(PF_ROUTE,  SOCK_RAW, AF_UNSPEC) socket. But
that is far from ideal - as often it is nicer to have the IP address
linger around a bit longer.)

Thanks,

Dw