I used the same trick to modify how X11 server sends keyboard messages. There's a boolean flag that denotes whether or not a key event is "real" or generated ar

I used the same trick to modify how X11 server sends keyboard messages. There's a boolean flag that denotes whether or not a key event is "real" or generated artificially. For some !@$!@'d up reason, 99% of apps actually discard all synthetic keyboard events. So doing something as innocent as mapping joystick to keyboard commands fails. It also took HOURS to find out why my keyboard generating test code wouldn't work until I piped it to an Ubuntu postit note program and hazzah... it worked with no code changes. Every other app was just blocking the events.