DPMS event notification

[Taylor Braun-Jones]

I'm trying to hook into DPMS events so that I can run my own actions
when DPMS enters on/standby/suspend/off modes (actually, for my
purposes all I care about is "On" and "Not on"). I've been searching
around and discovered that the XDPMS extension supposedly got some
sort of event notification a couple years ago, but I don't see any
evidence of that in X11/extensions/dpms*.h. In fact, dpmsproto.h seems
to indicate that it's definitely not there:

#define DPMSNumberEvents 0

fwiw - my need for this to work around broken DPMS support in my TV
which I'm driving via HDMI output. The DPMS signal doesn't actually
power off the back light so I'd like to use the TV's RS-232 command
interface to achieve that (which is already working nicely for
startup/shutdown/suspend/wakeup events).

I'm on an Ubuntu 11.10 box with the default xserver-xorg-core package
(currently 2:1.10.4-1ubuntu4.2)

Thanks for the help,
Taylor