Wait until a requested event is finished in X11

Question

I want to resize some window with

XResizeWindow(display, xid, width, height) 

which was created by another application and waits until it is really resized.

I tried the following:

XSync(display, 0) 

but it does not work.

Any suggestions?

Answer 1

XSync just ensures the request has been delivered to the Xserver, and doesn't wait for the other application and/or window manager to deal with the request.

Have you tried registering for ConfigureNotify events on that window?