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

       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(3), XkbGetMap(3), XSetPointerMapping(3)
       Xlib - C Language X Interface