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.
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.