XGetDeviceKeyMapping(3X11)XGetDeviceKeyMapping(3X11)NAME
XGetDeviceKeyMapping, XChangeDeviceKeyMapping - query or change device
key mappings
SYNOPSIS
XChangeDeviceKeyMapping(display, device, first_keycode,
keysyms_per_keycode, keysyms, keycode_count)
Display *display;
XDevice *device;
int first_keycode;
int keysyms_per_keycode;
KeySym *keysyms;
int keycode_count;
KeySym *XGetDeviceKeyMapping(display, device, first_keycode, key‐
code_count, keysyms_per_keycode_return)
Display *display;
XDevice *device;
KeyCode first_keycode;
int keycode_count;
int *keysyms_per_keycode_return;
ARGUMENTS
Specifies the connection to the X server. Specifies the device whose
key mapping is to be queried or modified. Specifies the first KeyCode
to be returned. Specifies the number of KeyCodes to be returned or
modified. Specifies the number of KeySyms per KeyCode. Specifies the
address of a variable into which the number of KeySyms per KeyCode will
be returned. 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 indi‐
vidual 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
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. This error may occur if an XGetDeviceKeyMapping or XChangeDe‐
viceKeyMapping request was made specifying a device that has no keys.
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. The server failed to
allocate the requested resource or server memory.
SEE ALSOXSetDeviceButtonMapping(3X11), XSetDeviceModifierMapping(3X11)
Programming with Xlib
XGetDeviceKeyMapping(3X11)
