Shared access to Mac OS X: how to manage wakeonlan and sleep

[Jean-Michel Pouré]

Dear Friends,

I just bought a G4 PowerMac (PPC) installed with Mac OS X 10.5 . This
was a rather good bargain as it works quite well and compiles fine. And
rather quickly.

We share this computer over Internet for Kdenlive project. I am making
this post on MacPorts devel because several projects may be interested
in the solution.

The Mac goes to sleep automatically after 3 hours of inactivity.

My questions :

* How can I manage sleep so that it is triggered after an SSH
disconnection and let's say 30 minutes of inactivity.

* When using screen, I would like to be sure that the Mac does not go to
sleep.

* Is sleep state safe?

I would like to know if some of you have innovating solutions. This is
only a compilation platform. We also have VNC access to view the result
and verify that Kdenlive runs smoothly.

Kind regards,
Jean-Michel