XChangeKeyboardMapping(XS) 6 January 1993 XChangeKeyboardMapping(XS)
X Version 11 (Release 5)
Name
XChangeKeyboardMapping - manipulate keyboard encoding and keyboard
encoding structure
Syntax
XChangeKeyboardMapping(display, first_keycode, keysyms_per_keycode, keysyms,
num_codes)
Display *display;
int first_keycode;
int keysyms_per_keycode;
KeySym *keysyms;
int num_codes;
KeySym *XGetKeyboardMapping(display, first_keycode, keycode_count,
keysyms_per_keycode_return)
Display *display;
KeyCode first_keycode;
int keycode_count;
int *keysyms_per_keycode_return;
XDisplayKeycodes(display, min_keycodes_return, max_keycodes_return)
Display *display;
int *min_keycodes_return, *max_keycodes_return;
int XSetModifierMapping(display, modmap)
Display *display;
XModifierKeymap *modmap;
XModifierKeymap *XGetModifierMapping(display)
Display *display;
XModifierKeymap *XNewModifiermap(max_keys_per_mod)
int max_keys_per_mod;
XModifierKeymap *XInsertModifiermapEntry(modmap, keycode_entry, modifier)
XModifierKeymap *modmap;
KeyCode keycode_entry;
int modifier;
XModifierKeymap *XDeleteModifiermapEntry(modmap, keycode_entry, modifier)
XModifierKeymap *modmap;
KeyCode keycode_entry;
int modifier;
XFreeModifiermap(modmap)
XModifierKeymap *modmap;
Arguments
display Specifies the connection to the X server.
firstkeycode Specifies the first KeyCode that is to be changed or
returned.
keycodecount Specifies the number of KeyCodes that are to be returned.
keycodeentry Specifies the KeyCode.
keysyms Specifies an array of KeySyms.
keysymsperkeycode
Specifies the number of KeySyms per KeyCode.
keysymsperkeycodereturn
Returns the number of KeySyms per KeyCode.
maxkeyspermod
Specifies the number of KeyCode entries preallocated to
the modifiers in the map.
maxkeycodesreturn
Returns the maximum number of KeyCodes.
minkeycodesreturn
Returns the minimum number of KeyCodes.
modifier Specifies the modifier.
modmap Specifies the XModifierKeymap structure.
numcodes Specifies the number of KeyCodes that are to be changed.
Description
The XChangeKeyboardMapping function defines the symbols for the specified
number of KeyCodes starting with firstkeycode. The symbols for KeyCodes
outside this range remain unchanged. The number of elements in keysyms
must be:
num_codes * keysyms_per_keycode
The specified firstkeycode must be greater than or equal to minkeycode
returned by XDisplayKeycodes, or a ``BadValue'' error results. In addi-
tion, the following expression must be less than or equal to maxkeycode
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
index in keysyms, counting from zero:
(K - first_keycode) * keysyms_per_keycode + N
The specified keysymsperkeycode 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 Key-
Codes. It is legal for NoSymbol to appear in nontrailing positions of
the effective list for a KeyCode. XChangeKeyboardMapping generates 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 firstkeycode. The value specified in
firstkeycode must be greater than or equal to minkeycode as returned by
XDisplayKeycodes, or a ``BadValue'' error results. In addition, the fol-
lowing expression must be less than or equal to maxkeycode as returned
by XDisplayKeycodes:
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 keysymsperkeycodereturn 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
returned 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 gen-
erates a MappingNotify event, and XSetModifierMapping returns MappingSuc-
cess. X permits at most eight modifier keys. If more than eight are
specified in the XModifierKeymap structure, a ``BadLength'' error
results.
The modifiermap member of the XModifierKeymap structure contains eight
sets of maxkeypermod 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 minkeycode
and maxkeycode in the Display structure, or a ``BadValue'' error
results.
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 status
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 logically 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 modifiers.
The structure should be freed after use by calling XFreeModifiermap. 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 XModi-
fierKeymap 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 accepted. Any argument defined as a
set of alternatives can generate this error.
See also
XFree(XS), XSetPointerMapping(XS)
Xlib - C Language X Interface