XSendEvent(3X11) XLIB FUNCTIONS XSendEvent(3X11)
NAME
XSendEvent, XDisplayMotionBufferSize, XGetMotionEvents,
XTimeCoord - send events and pointer motion history struc-
ture
SYNTAX
Status XSendEvent(Display *display, Window w, Bool pro-
pagate, 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 his-
tory 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 con-
tains the pointer; otherwise, the destination window is
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XSendEvent(3X11) XLIB FUNCTIONS XSendEvent(3X11)
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 win-
dow 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. Oth-
erwise, 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; there-
fore these fields and the display field are ignored by XSen-
dEvent.
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;
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XSendEvent(3X11) XLIB FUNCTIONS XSendEvent(3X11)
XGetMotionEvents returns NULL. If the stop time is in the
future, it is equivalent to specifying CurrentTime. XGetMo-
tionEvents 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 gen-
erate this error.
BadWindow 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
XFree86 Version 4.5.0 3