Screen saver support

[Laurent Birtz <birtz dmi usherb ca>]

Greetings,

I've written yet another cycle-scavenging application that behaves
like a screen saver (similar to seti home). I need to start the screen 
saver when the machine is idle (no user logged in). On UNIX, I am
hoping that GDM can help with that.

I noticed the BackgroundProgram option in gdm.conf. It almost does
what I want, but not exactly so. Firstly, it starts the program right
away, without some delay for the user to log back. Secondly, once the
program exits, it is not restarted after awhile. My application detects
mouse movements and keystrokes, and respond by quitting ASAP, to stop
interfering with what the user is doing.

If there was an option to (re)start the program after some configurable
delay, it would be a perfect environment for a screen saver.

The other avenues I am considering is setting up timed auto-login to
start the screen saver, and using a cron job to regularly check if
GDM is waiting for a user to login and if so, spawn the screen saver on
the console used by GDM (by stealing its cookie file). I'm reluctant
to engage in this because ideally it should be simple to install my 
application.

Can you guys suggest the best course of action to me?

Thanks a lot for your time,
Laurent Birtz