how does an app know that the system wants to go to sleep?

[Christopher Lang]

Hi,

is there a possibility that an application gets notified when a system wants 
to got to suspend?

I was reading through the chapter 4 "Locking" in the HAL specs, and an 
application may hold a lock, which may disable the suspend function, until 
the app releases the lock.

When holding the lock, how would an application find out that the system wants 
to go to sleep, and then possibly finish off some stuff, then release the 
lock and the system then may go to sleep?

many thaks
Chris

http://www.acurana.de/