GDK_INPUT_OUTPUT windows are the standard kind of window you might expect.
Such windows receive events and are also displayed on screen.
GDK_INPUT_ONLY windows are invisible; they are usually placed above other
windows in order to trap or filter the events. You can't draw on
GDK_INPUT_ONLY windows.
GDK_INPUT_OUTPUT
window for graphics and events
GDK_INPUT_ONLY
window for events only
GDK_INPUT_OUTPUT windows are the standard kind of window you might expect. Such windows receive events and are also displayed on screen. GDK_INPUT_ONLY windows are invisible; they are usually placed above other windows in order to trap or filter the events. You can't draw on GDK_INPUT_ONLY windows. GDK_INPUT_OUTPUT window for graphics and events GDK_INPUT_ONLY window for events only