This manual page is for Mac OS X version 10.6.3

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XQueryDeviceState(3)                             X FUNCTIONS                            XQueryDeviceState(3)



NAME
       XQueryDeviceState - query the state of an extension input device.

SYNTAX
       int XQueryDeviceState(Display *display, XDevice *device);

ARGUMENTS
       display     Specifies the connection to the X server.

       device      Specifies the device whose state is to be queried.

DESCRIPTION
       The  XQueryDeviceState  request  queries the state of an input device.  The current state of keys and
       buttons (up or down), and valuators (current value) on the device is reported by this request.   Each
       key  or  button is represented by a bit in the XDeviceState structure that is returned.  Valuators on
       the device report 0 if they are reporting relative information, and the current  value  if  they  are
       reporting absolute information.

       XQueryDeviceState can generate a BadDevice error.

STRUCTURES
       The XDeviceState structure contains:

       typedef struct {
            XID device_id;
            int num_classes;
            XInputClass *data;
       } XDeviceState;

       The XValuatorState structure contains:

       typedef struct {
            unsigned char class;
            unsigned char length;
            unsigned char num_valuators;
            unsigned char mode;
            int *valuators;
       } XValuatorState;

       The XKeyState structure contains:

       typedef struct {
            unsigned char class;
            unsigned char length;
            short         num_keys;
            char keys[32];
       } XKeyState;

       The XButtonState structure contains:

       typedef struct {
            unsigned char class;
            unsigned char length;
            short         num_buttons;
            char buttons[32];
       } XButtonState;

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  some  other
                   client  has  caused the specified device to become the X keyboard or X pointer device via
                   the XChangeKeyboardDevice or XChangePointerDevice requests.

SEE ALSO
       Programming with Xlib



X Version 11                                     libXi 1.2.1                            XQueryDeviceState(3)