devctl (alike?) for devfs

[M. Warner Losh]

In message: <480EE53C.40800 at icyb.net.ua>
            Andriy Gapon <avg at icyb.net.ua> writes:
: on 23/04/2008 00:06 Jille said the following:
: > Andriy Gapon wrote:
: >> Maybe this is a crazy idea or maybe we already have something like this.
: >> Is it possible to get notifications about changes in devfs - appearance
: >> and disappearance of devices (in devfs sense of the word)?
: >> devctl currently notifies about real (hardware) devices handled by
: >> device drivers and some notifications about hardware/driver events.
: >> But what if I want to automatically run some action if
: >> /dev/ufs/magic-label appears?
: >> Or if I want to monitor appearance and disappearance of ad* and da*
: >> devices (without having to monitor low level drivers like umass)?
: >>
: > 
: > I don't know whether it is what you are looking for, but take a look at 
: > devd(8).
: 
: devd reads devctl

The device events from devctl(4) don't necessarily correspond to /dev
entries that devfs deals with.

Warner