Xlib owns the event queue. Use the Xlib event-handling functions. Do not
call the XCB event-handling functions.
XCB owns the event queue. Use the XCB event-handling functions. Do not call
the Xlib event-handling functions.
While a client using Xlib/XCB can issue requests and handle their replies or
errors with either Xlib or XCB, only one can own and handle the event queue.
By default, Xlib must own the event queue, for compatibility with legacy Xlib
clients. Clients can call XSetEventQueueOwner immediately after
XOpenDisplay to let XCB own the event queue instead. Clients may not
call XSetEventQueueOwner at any other time, as this will potentially