XGETDEVICEKEYMAPPING(3) libXi XGETDEVICEKEYMAPPING(3)NAME
XGetDeviceKeyMapping, XChangeDeviceKeyMapping - query or change device
key mappings
SYNTAX
#include <X11/extensions/XInput.h>
KeySym *XGetDeviceKeyMapping(Display *display, XDevice *device,
KeyCode first_keycode, int keycode_count,
int *keysyms_per_keycode_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 modified.
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 KeyCodewill 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_keycode. 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
elements 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_keycode 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 nontrailing
positions of the effective list for a KeyCode.XChangeDeviceKeyMapping
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 specified 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 specified for an argument, the
full range defined by the argument'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 ALSOXSetDeviceButtonMapping(3), XSetDeviceModifierMapping(3)
03/04/2009 XGETDEVICEKEYMAPPING(3)