Synchronizing _NET_WM_STATE writes and reads

[Peter Hutterer]

Matthias Käppler wrote:
> What if the client triggers a state change and some other client wants to
> retrieve information about that window shortly thereafter? I need pull
> semantics where clients are able to retrieve the currently active states
> instead of pub/sub semantics.

the problem is not unfamiliar to the synchronisation issues in 
multithreaded environments.

you're basically calling for making the action and setting of the 
property an atomar operation. this is hard enough for simple operations 
like incrementing a variable, making something complex like changing a 
window's properties a window and then setting an atom on the X server 
indivisible doesn't make it easier.

so no - I don't think there's a way to get around it.

Cheers,
   Peter