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XGETDEVICEMOTIONEVEN(3)				       XGETDEVICEMOTIONEVEN(3)

NAME
       XGetDeviceMotionEvents, XDeviceTimeCoord	- get device motion history

SYNOPSIS
       #include	<X11/extensions/XInput.h>

       XDeviceTimeCoord	*XGetDeviceMotionEvents( Display *display,
						 XDevice *device,
						 Time start,
						 Time stop,
						 int *nevents_return,
						 int *mode_return,
						 int *axis_count_return);

       display
	      Specifies	the connection to the X	server.

       device
	      Specifies	the device whose motion	history	is to be
	      queried.

       start, stop
	      Specify the time interval	in which the events are
	      returned from the	motionhistory buffer.You can pass a
	      timestamp	or CurrentTime.

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

       mode_return
	      Returns the mode of the device (Absolute or Relative).

       axis_count_return
	      Returns the count	of axes	being reported.

DESCRIPTION
	   The server may retain the recent history of the device motion
	   and do so to	a finer	granularity than is reported by
	   DeviceMotionNotify events. The XGetDeviceMotionEvents request
	   makes this history available.

	   The XGetDeviceMotionEvents request returns all events in the
	   motion history buffer that fall between the specified start and
	   stop	times, inclusive. If the start time is later than the stop
	   time	or if the start	time is	in the future, no events are
	   returned. If	the stop time is in the	future,	it is equivalent
	   to specifying CurrentTime.

	   The mode indicates whether the device is reporting absolute
	   positional data (mode = Absolute ) or relative motion data
	   (mode = Relative ). Some devices allow their	mode to	be changed
	   via the XSetDeviceMode request. These constants are defined in
	   the file XI.h. The axis_count returns the number of axes or
	   valuators being reported by the device.

	   XGetDeviceMotionEvents can generate a BadDevice, or BadMatch
	   error.

       Structures

	   The XDeviceTimeCoord	structure contains:

	   typedef struct {
	       Time time;
	       int *data;
	   } XDeviceTimeCoord;

	   The time member is set to the time, in milliseconds.	The data
	   member is a pointer to an array of integers.	These integers are
	   set to the values of	each valuator or axis reported by the
	   device. There is one	element	in the array per axis of motion
	   reported by the device. The value of	the array elements depends
	   on the mode of the device. If the mode is Absolute, the values
	   are the raw values generated	by the device. These may be scaled
	   by client programs using the	maximum	values that the	device can
	   generate. The maximum value for each	axis of	the device is
	   reported in the max_val field of the	XAxisInfo returned by the
	   XListInputDevices request. If the mode is Relative, the data
	   values are the relative values generated by the device.

	   You should use XFreeDeviceMotionEvents to free the data
	   returned by this request.

	   Errors returned by this request: BadDevice, BadMatch.

DIAGNOSTICS
	   BadDevice
		  An invalid device was	specified. The specified device
		  does not exist or has	not been opened	by this	client via
		  XOpenInputDevice. This error may also	occur if the
		  specified device is the X keyboard or	X pointer device.

	   BadMatch
		  This error may occur if an XGetDeviceMotionEvents
		  request is made specifying a device that has no
		  valuators and	reports	no axes	of motion.

				  03/09/2013	       XGETDEVICEMOTIONEVEN(3)

NAME | SYNOPSIS | DESCRIPTION | DIAGNOSTICS

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