the edge or corner from which the drag is started
the device used for the operation
the button being used to drag, or 0 for a keyboard-initiated drag
root window X coordinate of mouse click that began the drag
root window Y coordinate of mouse click that began the drag
timestamp of mouse click that began the drag (use gdk_event_get_time())
3.4
Begins a window resize operation (for a toplevel window). You might use this function to implement a “window resize grip,” for example; in fact #GtkStatusbar uses it. The function works best with window managers that support the Extended Window Manager Hints
but has a fallback implementation for other window managers.