[PyQt] testing if another instance of a script is already running

[Strato]

Hi folks,

I want to write some kind of test to check at startup if another 
instance of my application is already running.

I don't want to handle this by writing a PID file to the disk because it 
is too Unix/Linux specific way to do this, and I need to keep the code 
to be cross-platform.

I think the better way to achieve this is to use some process control, 
but I'm a neebie and I don't see how to do this in a safe and clean way.

Maybe PyQt have a class or a method that handle this ?

Any idea ?

Best regards,
Strato