Tribblix: manual page: XChangeKeyboardMapping.3

XChangeKeyboardMapping(3) XLIB FUNCTIONS XChangeKeyboardMapping(3)

NAME

XChangeKeyboardMapping, XGetKeyboardMapping, XDisplayKeycodes,
XSetModifierMapping, XGetModifierMapping, XNewModifiermap,
XInsertModifiermapEntry, XDeleteModifiermapEntry, XFreeModifiermap,
XModifierKeymap - manipulate 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,
KeyCode keycode_entry, int modifier);

XModifierKeymap *XDeleteModifiermapEntry(XModifierKeymap *modmap,
KeyCode 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
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 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
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.
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 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 following 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
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 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 generates a MappingNotify event, and XSetModifierMapping
returns MappingSuccess. 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_keycode and max_keycode 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
structure for later use.

The XInsertModifiermapEntry function adds the specified KeyCode to
the set that controls the specified modifier and returns the
resulting XModifierKeymap 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
structure.

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