XGetDeviceKeyMapping

XGetDeviceKeyMapping(3X11)	 X FUNCTIONS	   XGetDeviceKeyMapping(3X11)



NAME
       XGetDeviceKeyMapping, XChangeDeviceKeyMapping - query or change device
       key mappings

SYNTAX
	int XChangeDeviceKeyMapping(Display *display,  XDevice	*device,  int
       first_keycode,  int  keysyms_per_keycode,  KeySym  *keysyms,  int key-
       code_count);

       KeySym *XGetDeviceKeyMapping(Display *display, XDevice  *device,	 Key-
	      Code  first_keycode,  int	 keycode_count, int *keysyms_per_key-
	      code_return);


ARGUMENTS
       display	   Specifies the connection to the X server.

       device	   Specifies the device whose key mapping is to be queried or
		   modified.

       first_keycode
		   Specifies the first KeyCode to be returned.

       keycode_count
		   Specifies  the  number of KeyCodes to be returned or modi-
		   fied.

       keysyms_per_keycode
		   Specifies the number of KeySyms per KeyCode.

       keysyms_per_keycode_return
		   Specifies the address of a variable into which the  number
		   of KeySyms per KeyCode will be returned.

       keysyms	   Specifies the address of an array of KeySyms.

DESCRIPTION
       For the specified device, the XGetDeviceKeyMapping request returns the
       symbols for the specified number of KeyCodes starting with  first_key-
       code.   The  value  specified in first_keycode must be greater than or
       equal to min_keycode as returned by XListInputDevices, or  a  BadValue
       error  results.	 In  addition,	the following expression must be less
       than or equal to max_keycode as returned by XListInputDevices:

       first_keycode + keycode_count - 1

       If this is not the case, a BadValue error results.  The number of ele-
       ments in the KeySyms list is:

       keycode_count * keysyms_per_keycode_return

       KeySym  number  N, counting from zero, for KeyCode K has the following
       index  in  the  list,  counting	from  zero:  (K	  -   first_code)   *
       keysyms_per_code_return + N

       The  X server arbitrarily chooses the keysyms_per_keycode_return value
       to be large enough to report all requested symbols.  A special  KeySym
       value  of  NoSymbol  is used to fill in unused elements for individual
       KeyCodes.  To free the storage returned by  XGetDeviceKeyMapping,  use
       XFree.

       If  the specified device does not support input class keys, a BadMatch
       error will result.

       XGetDeviceKeyMapping can generate a BadDevice, BadMatch,	 or  BadValue
       error.

       For  the specified device, the XChangeDeviceKeyMapping request defines
       the symbols  for	 the  specified	 number	 of  KeyCodes  starting	 with
       first_keycode.	The  symbols  for  KeyCodes outside this range remain
       unchanged.  The number of elements in keysyms must be:

       num_codes * keysyms_per_keycode

       The specified first_keycode must be greater than or equal to  min_key-
       code  returned  by XListInputDevices, or a BadValue error results.  In
       addition, the following expression must	be  less  than	or  equal  to
       max_keycode  as	returned  by  XListInputDevices,  or a BadValue error
       results:

       first_keycode + num_codes - 1

       KeySym number N, counting from zero, for KeyCode K has  the  following
       index in keysyms, counting from zero:

       (K - first_keycode) * keysyms_per_keycode + N

       The  specified  keysyms_per_keycode  can	 be chosen arbitrarily by the
       client to be large enough to hold  all  desired	symbols.   A  special
       KeySym value of NoSymbol should be used to fill in unused elements for
       individual KeyCodes.  It is legal for NoSymbol to appear in  nontrail-
       ing  positions  of  the	effective  list	 for  a	 KeyCode.  XChangeDe-
       viceKeyMapping generates a DeviceMappingNotify event that is  sent  to
       all clients that have selected that type of event.

       There  is no requirement that the X server interpret this mapping.  It
       is merely stored for reading and writing by clients.

       If the specified device does not support input class keys, a  BadMatch
       error results.

       XChangeDeviceKeyMapping	can generate a BadDevice, BadMatch, BadAlloc,
       or BadValue  error.


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 speci-
		   fied device is the X keyboard or X pointer device.

       BadMatch	   This	  error	 may  occur  if	 an  XGetDeviceKeyMapping  or
		   XChangeDeviceKeyMapping  request  was  made	specifying  a
		   device that has no keys.

       BadValue	   Some	 numeric  value	 falls	outside	 the  range of values
		   accepted by the request.  Unless a specific range is spec-
		   ified for an argument, the full range defined by the argu-
		   ment’s type is accepted.  Any argument defined as a set of
		   alternatives can generate this error.

       BadAlloc	   The	server	failed	to allocate the requested resource or
		   server memory.

SEE ALSO
       XSetDeviceButtonMapping(3X11)
       XSetDeviceModifierMapping(3X11)
       Programming with Xlib



						   XGetDeviceKeyMapping(3X11)