XCirculateEvent - CirculateNotify event structure
The structure for CirculateNotify events contains:
typedef struct {
int type; CirculateNotify
unsigned long serial; # of last request processed by server
Bool send_event; true if this came from a SendEvent request
Display *display; Display the event was read from
Window event;
Window window;
int place; PlaceOnTop, PlaceOnBottom
} XCirculateEvent;