Hello
Is there away to detect in linux if the keyboard is in use, or mouse is moved, just need to determine if either is being used.
If neither is being is being used say after an hour, initiate a system shutdown.
Thanks Glenn

Depends on the definition of "used".

That is what the screen lock function does when it locks the display.

The problem is that if the system is being used (watching a video), then neither the keyboard or mouse will be used - and that could cause the system to shutdown.

If the system is being used to compute some long running job (gene mapping/splicing/finite element analysis/animation generation...) then again neither the keyboard and mouse will be used.

Then there is the issue when multiple keyboards and mice are used...

Which desktop enviroment are you running? I beleive both KDE and Gnome have a way built in.

A more generic way (should work for any X windows based system) would be to use xautolock.

running the command when you start your session should do it:
This has all the problems above it is only based on keyboared/mouse activity. So it may cut out if you watching TV or doing somthing that takes more than an hour. Check out the man pages for xautolock for more details. Alternative would be to hibernate or suspend (pm-hibernate or pm-suspend instead of poweroff) it will still break the flow but at least you will be able to resume and not lose work.

You could also just meassage users if this would be an issue, xautolock supports this to.
Warning: I can not test this now (I am just reading man pages, so take with a pinch of salt. and please test before actually using it).

Maybe hack into your screensaver and put a hook in there to initiate a shutdown script? I don't know the answer to this - but are screensavers that you choose from the GUI configuration actual executables? If so, replace one with your own shutdown executable.

Something with /proc/interrupts?