Table of Contents
XSendEvent, XDisplayMotionBufferSize,
XGetMotionEvents, XTimeCoord - send events and pointer motion history structure
- 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);
- 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,.
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.
The XTimeCoord structure contains:
0
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.
- 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.
XAnyEvent(3X11)
, XIfEvent(3X11)
, XNextEvent(3X11)
, XPutBackEvent(3X11)
Xlib - C Language X Interface
Table of Contents