plucky (3) XDisplayMotionBufferSize.3.gz

Provided by: libx11-doc_1.8.10-2_all bug

NAME

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

SYNTAX

       Status XSendEvent(Display *display, Window w, Bool propagate, long event_mask, XEvent *event_send);

       unsigned long XDisplayMotionBufferSize(Display *display);

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

ARGUMENTS

       display   Specifies the connection to the X server.

       event_mask
                 Specifies the event mask.

       event_send
                 Specifies the event that is to be sent.

       nevents_return
                 Returns the number of events from the motion history buffer.

       propagate Specifies a Boolean value.

       start
       stop      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.

       w         Specifies the window the window the event is to be sent to.

DESCRIPTION

       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:

       •    If w is PointerWindow, the destination window is the window that contains the pointer.

       •    If w is InputFocus and if the focus window contains the  pointer,  the  destination  window  is  the
            window that contains the pointer; otherwise, the destination window is the focus window.

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

       •    If event_mask is the empty set, the event is sent to the client that created the destination window.
            If that client no longer exists, no event is sent.

       •    If  propagate  is False, the event is sent to every client selecting on destination any of the event
            types in the event_mask argument.

       •    If propagate is True and no clients have selected on destination any of the event  types  in  event-
            mask, the destination is replaced with the closest ancestor of destination for which some client has
            selected a type in event-mask and for which no intervening window  has  that  type  in  its  do-not-
            propagate-mask.   If  no  such window exists or if the window is an ancestor of the focus window and
            InputFocus was originally specified as the destination, the  event  is  not  sent  to  any  clients.
            Otherwise, the event is reported to every client selecting on the final destination any of the types
            specified in event_mask.

       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.

STRUCTURES

       The XTimeCoord structure contains:

       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.

DIAGNOSTICS

       BadValue  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.

       BadWindow A value for a Window argument does not name a defined Window.

SEE ALSO

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