device activity checking for powersaver on a linux laptop

[Fabian Lienert]

Dear pythonists,

I am new to python and want to write a program, that saves battery power on
a linux laptop. For example it should power off the display, when there is no
keyboard or mouse activity for a minute.

My first problem is: I cannot found a /dev device for the keyboard. And raw_input doesn't make sense,
because it is like a prompt, its impossible to check for keyboard activity.

So i focused first on the mouse. Here I know the linux device is /dev/psaux. I can "cat /dev/psaux" on
a shell and see that there is some input if i use the mouse. So i wrote a quick test script like this:
--
import string,re,time,sys

class Idle:
    def __init__(self):
    	import sys,time
        mouse_dev = open('/dev/psaux','r')
        while mouse_dev:
            if mouse_dev == '':
                time.sleep(60)
                open('/dev/psaux','r')          
		print "Idle"
                continue
            else:
                print mouse_dev
                continue
--

It does not work, as you see, because mouse_dev is an existing object, it is not == ''
Also with mouse_dev.read(): doesn't work.

How can I check if the mouse_dev is "empty" in the meaning that there is no 
activity?

And how can I check for keyboard activity? 


Thanks in advance for help!
Fabian
-- 
Fabian Lienert | mitLinks AG | Limmatstrasse 291 | 8005 Zürich
lienert at mitlinks.ch | ++41 1 444 10 44 | http://www.mitlinks.ch
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