coroutines — avoid the busy wait

[Mildred <ml.mildred593@...>]

Hi,

I'm creating a program to handle infrared events from my remote control
and perform several different actions. Basically, I just wait in a loop
for IR events, and perform the actions I want. But now, sometimes I
want to draw a menu on the screen. So I set up an X11 window and draw
text on it. The problem is that it is never refreshed. So if another
window goes in front of it, the drawing is lost.

So I thought about using coroutines and the problem is that nothing may
happen for a long time. So my scheduler would just go from a thread to
another just to check there is nothing to do ... a busy wait.

I don't know how I could solve that. I can't use the method described
in the PiL (that calling a function that will sleep until a socket
receive data) since the threads are triggered by different kind of
events.

Also, i don't like to add a sleep in the scheduler because it would
force my CPU to resume (and so, consume power) even if it has nothing
to do.

Can you help me ?

Thanks.
Mildred

-- 
Mildred Ki'lya
E-Mail:	mildred593(at)online.fr

Site:	<http://mildred632.free.fr/>
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