Manpages - XChangePointerDevice.3

XChangePointerDevice - change which device is the X pointer

  #include <X11/extensions/XInput.h>

  Status XChangePointerDevice( Display *display,
                               XDevice *device,
                               int xaxis,
                               int yaxis);

  display
         Specifies the connection to the X server.

  device
         Specifies the device to be used as the X pointer.

  xaxis
         Specifies the axis of the device to be used as the X
         pointer x-axis.

  yaxis
         Specifies the axis of the device to be used as the X
         pointer y-axis.

    The XChangePointerDevice request causes the server to use the
    specified device as the X pointer. The device must have been
    opened by the client via XOpenDevice or a BadDevice error will
    result. The device must support input class Valuators or a
    BadMatch error will result. If the implementation does not
    support use of the specified device as the X pointer, a
    BadDevice error will result.

    If the specified device is grabbed by another client,
    AlreadyGrabbed is returned. If the specified device is frozen
    by a grab on another device, GrabFrozen is returned. If the
    request is successful, Success is returned.

    If the request succeeds, a ChangeDeviceNotify event is sent to
    all clients that have selected that event. A MappingNotify
    event with request = MappingPointer is sent to all clients. The
    specified device becomes the X pointer, and the old X pointer
    becomes accessible through the input extension protocol
    requests.

    XChangePointerDevice can generate a BadDevice or a BadMatch
    error.

    BadDevice
           An invalid device was specified. The specified device
           does not exist, has not been opened by this client via
           XOpenInputDevice, or is already one of the core X input
           devices (pointer or keyboard). This error may also occur
           if the server implementation does not support using the
           specified device as the X pointer.

    BadMatch
           This error may occur if an XChangePointerDevice request
           was made specifying a device that has less than two
           valuators, or specifying a valuator index beyond the
           range supported by the device.

    XChangeKeyboardDevice(3)