XChangeKeyboardMapping(3) XLIB FUNCTIONS XChangeKeyboardMapping(3)
NAME
XChangeKeyboardMapping, XGetKeyboardMapping, XDisplayKeycodes, XSetModi-
fierMapping, XGetModifierMapping, XNewModifiermap, XInsertModifiermapEn-
try, XDeleteModifiermapEntry, XFreeModifiermap, XModifierKeymap - manip-
ulate keyboard encoding and keyboard encoding structure
SYNTAX
int XChangeKeyboardMapping(Display *display, int first_keycode, int
keysyms_per_keycode, KeySym *keysyms, int num_codes);
KeySym *XGetKeyboardMapping(Display *display, KeyCode first_keycode, int
keycode_count, int *keysyms_per_keycode_return);
int XDisplayKeycodes(Display *display, int *min_keycodes_return, int
*max_keycodes_return);
int XSetModifierMapping(Display *display, XModifierKeymap *modmap);
XModifierKeymap *XGetModifierMapping(Display *display);
XModifierKeymap *XNewModifiermap(int max_keys_per_mod);
XModifierKeymap *XInsertModifiermapEntry(XModifierKeymap *modmap, Key-
Code keycode_entry, int modifier);
XModifierKeymap *XDeleteModifiermapEntry(XModifierKeymap *modmap, Key-
Code keycode_entry, int modifier);
int XFreeModifiermap(XModifierKeymap *modmap);
ARGUMENTS
display Specifies the connection to the X server.
first_keycode
Specifies the first KeyCode that is to be changed or returned.
keycode_count
Specifies the number of KeyCodes that are to be returned.
keycode_entry
Specifies the KeyCode.
keysyms Specifies an array of KeySyms.
keysyms_per_keycode
Specifies the number of KeySyms per KeyCode.
keysyms_per_keycode_return
Returns the number of KeySyms per KeyCode.
max_keys_per_mod
Specifies the number of KeyCode entries preallocated to the
modifiers in the map.
max_keycodes_return
Returns the maximum number of KeyCodes.
min_keycodes_return
Returns the minimum number of KeyCodes.
modifier Specifies the modifier.
modmap Specifies the XModifierKeymap structure.
num_codes Specifies the number of KeyCodes that are to be changed.
DESCRIPTION
The XChangeKeyboardMapping function defines the symbols for the speci-
fied 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 XDisplayKeycodes, or a BadValue error results. In addition,
the following expression must be less than or equal to max_keycode as
returned by XDisplayKeycodes, or a BadValue error results:
first_keycode + num_codes - 1
KeySym number N, counting from zero, for KeyCode K has the following in-
dex 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 individ-
ual KeyCodes. It is legal for NoSymbol to appear in nontrailing posi-
tions of the effective list for a KeyCode. XChangeKeyboardMapping gen-
erates a MappingNotify event.
There is no requirement that the X server interpret this mapping. It is
merely stored for reading and writing by clients.
XChangeKeyboardMapping can generate BadAlloc and BadValue errors.
The XGetKeyboardMapping function 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 XDisplayKeycodes, or a BadValue error results. In addition, the fol-
lowing expression must be less than or equal to max_keycode as returned
by XDisplayKeycodes:
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 in-
dex 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 XGetKeyboardMapping, use XFree.
XGetKeyboardMapping can generate a BadValue error.
The XDisplayKeycodes function returns the min-keycodes and max-keycodes
supported by the specified display. The minimum number of KeyCodes re-
turned is never less than 8, and the maximum number of KeyCodes returned
is never greater than 255. Not all KeyCodes in this range are required
to have corresponding keys.
The XSetModifierMapping function specifies the KeyCodes of the keys (if
any) that are to be used as modifiers. If it succeeds, the X server
generates a MappingNotify event, and XSetModifierMapping returns Map-
pingSuccess. X permits at most 8 modifier keys. If more than 8 are
specified in the XModifierKeymap structure, a BadLength error results.
The modifiermap member of the XModifierKeymap structure contains 8 sets
of max_keypermod KeyCodes, one for each modifier in the order Shift,
Lock, Control, Mod1, Mod2, Mod3, Mod4, and Mod5. Only nonzero KeyCodes
have meaning in each set, and zero KeyCodes are ignored. In addition,
all of the nonzero KeyCodes must be in the range specified by min_key-
code and max_keycode in the Display structure, or a BadValue error re-
sults.
An X server can impose restrictions on how modifiers can be changed, for
example, if certain keys do not generate up transitions in hardware, if
auto-repeat cannot be disabled on certain keys, or if multiple modifier
keys are not supported. If some such restriction is violated, the sta-
tus reply is MappingFailed, and none of the modifiers are changed. If
the new KeyCodes specified for a modifier differ from those currently
defined and any (current or new) keys for that modifier are in the logi-
cally down state, XSetModifierMapping returns MappingBusy, and none of
the modifiers is changed.
XSetModifierMapping can generate BadAlloc and BadValue errors.
The XGetModifierMapping function returns a pointer to a newly created
XModifierKeymap structure that contains the keys being used as modi-
fiers. The structure should be freed after use by calling XFreeModi-
fiermap. If only zero values appear in the set for any modifier, that
modifier is disabled.
The XNewModifiermap function returns a pointer to XModifierKeymap struc-
ture for later use.
The XInsertModifiermapEntry function adds the specified KeyCode to the
set that controls the specified modifier and returns the resulting XMod-
ifierKeymap structure (expanded as needed).
The XDeleteModifiermapEntry function deletes the specified KeyCode from
the set that controls the specified modifier and returns a pointer to
the resulting XModifierKeymap structure.
The XFreeModifiermap function frees the specified XModifierKeymap struc-
ture.
STRUCTURES
The XModifierKeymap structure contains:
typedef struct {
int max_keypermod; /* This server's max number of keys per modifier */
KeyCode *modifiermap; /* An 8 by max_keypermod array of the modifiers */
} XModifierKeymap;
DIAGNOSTICS
BadAlloc The server failed to allocate the requested resource or server
memory.
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 ac-
cepted. Any argument defined as a set of alternatives can
generate this error.
SEE ALSO
XFree(3), XkbGetMap(3), XSetPointerMapping(3)
Xlib - C Language X Interface
X Version 11 libX11 1.8.12 XChangeKeyboardMapping(3)
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