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XSendEvent, XDisplayMotionBufferSize, XGetMotionEvents, XTimeCoord - send events and pointer motion history structure


Status XSendEvent(display, w, propagate, event_mask, event_send)
Display *display;

Window w;

Bool propagate;

long event_mask;

XEvent *event_send;

unsigned long XDisplayMotionBufferSize(display)
Display *display;

XTimeCoord *XGetMotionEvents(display, w, start, stop, nevents_return)
Display *display;

Window w;

Time start, stop;    

int *nevents_return;


Specifies the connection to the X server.
Specifies the event mask.
Specifies the event that is to be sent.
Returns the number of events from the motion history buffer.
Specifies a Boolean value.

Specify the time interval in which the events are returned from the motion history buffer. You can pass a timestamp or CurrentTime. PointerWindow, or InputFocus.
Specifies the window the window the event is to be sent to,.


The XSendEvent function identifies the destination window, determines which clients should receive the specified events, and ignores any active grabs. This function requires you to pass an event mask. For a discussion of the valid event mask names, see section 10.3. This function uses the w argument to identify the destination window as follows:

To determine which clients should receive the specified events, XSendEvent uses the propagate argument as follows:

The event in the XEvent structure must be one of the core events or one of the events defined by an extension (or a BadValue error results) so that the X server can correctly byte-swap the contents as necessary. The contents of the event are otherwise unaltered and unchecked by the X server except to force send_event to True in the forwarded event and to set the serial number in the event correctly; therefore these fields and the display field are ignored by XSendEvent.

XSendEvent returns zero if the conversion to wire protocol format failed and returns nonzero otherwise. XSendEvent can generate BadValue and BadWindow errors.

The server may retain the recent history of the pointer motion and do so to a finer granularity than is reported by MotionNotify events. The XGetMotionEvents function makes this history available.

The XGetMotionEvents function returns all events in the motion history buffer that fall between the specified start and stop times, inclusive, and that have coordinates that lie within the specified window (including its borders) at its present placement. If the server does not support motion history, if the start time is later than the stop time, or if the start time is in the future, no events are returned; XGetMotionEvents returns NULL. If the stop time is in the future, it is equivalent to specifying CurrentTime. XGetMotionEvents can generate a BadWindow error.


The XTimeCoord structure contains:

0>=40 .vs 0u
0<=39 .vs 0p
typedef struct {
    Time time;
    short x, y;
} XTimeCoord;

The time member is set to the time, in milliseconds. The x and y members are set to the coordinates of the pointer and are reported relative to the origin of the specified window.


Some numeric value falls outside the range of values accepted by the request. Unless a specific range is specified for an argument, the full range defined by the argument's type is accepted. Any argument defined as a set of alternatives can generate this error.
A value for a Window argument does not name a defined Window.

See Also

XAnyEvent(3X11) , XIfEvent(3X11) , XNextEvent(3X11) , XPutBackEvent(3X11)
Xlib - C Language X Interface

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