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Section: XKB FUNCTIONS (3) Updated: libX11 1.4.2
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XkbFreeClientMap - Free memory used by the client map member of an XkbDescRec structure  


void XkbFreeClientMap (XkbDescPtr xkb, unsigned int which, Bool free_all);


- xkb
keyboard description containing client map to free
- which
mask identifying components of map to free
- free_all
True => free all client components and map itself


XkbFreeClientMap frees the components of client map specified by which in the XkbDescRec structure specified by the xkb parameter and sets the corresponding structure component values to NULL. The which parameter specifies a combination of the client map masks shown in Table 1.

If free_all is True, which is ignored; XkbFreeClientMap frees every non-NULL structure component in the client map, frees the XkbClientMapRec structure referenced by the map member of the xkb parameter, and sets the map member to NULL.

Table 1 XkbAllocClientMap Masks


XkbKeyTypesMask The type_count field specifies the number of entries to preallocate for the types field of the client map. If the type_count field is less than XkbNumRequiredTypes returns BadValue.
XkbKeySymsMask The min_key_code and max_key_code fields of the xkb parameter are used to allocate the syms and key_sym_map fields of the client map. The fields are allocated to contain the maximum number of entries necessary for max_key_code - min_key_code + 1 keys.
XkbModifierMapMask The min_key_code and max_key_code fields of the xkb parameter are used to allocate the modmap field of the client map. The field is allocated to contain the maximum number of entries necessary for max_key_code - min_key_code + 1 keys.

NOTE: The min_key_code and max_key_code fields of the xkb parameter must be legal values if the XkbKeySymsMask or XkbModifierMapMask masks are set in the which parameter. If they are not valid, XkbAllocClientMap returns BadValue.  


The complete description of an Xkb keyboard is given by an XkbDescRec. The component structures in the XkbDescRec represent the major Xkb components.

typedef struct {
   struct _XDisplay * display;      /* connection to X server */
   unsigned short     flags;        /* private to Xkb, do not modify */
   unsigned short     device_spec;  /* device of interest */
   KeyCode            min_key_code; /* minimum keycode for device */
   KeyCode            max_key_code; /* maximum keycode for device */
   XkbControlsPtr     ctrls;        /* controls */
   XkbServerMapPtr    server;       /* server keymap */
   XkbClientMapPtr    map;          /* client keymap */
   XkbIndicatorPtr    indicators;   /* indicator map */
   XkbNamesPtr        names;        /* names for all components */
   XkbCompatMapPtr    compat;       /* compatibility map */
   XkbGeometryPtr     geom;         /* physical geometry of keyboard */
} XkbDescRec, *XkbDescPtr;

The display field points to an X display structure. The flags field is private to the library: modifying flags may yield unpredictable results. The device_spec field specifies the device identifier of the keyboard input device, or XkbUseCoreKeyboard, which specifies the core keyboard device. The min_key_code and max_key_code fields specify the least and greatest keycode that can be returned by the keyboard.

Each structure component has a corresponding mask bit that is used in function calls to indicate that the structure should be manipulated in some manner, such as allocating it or freeing it. These masks and their relationships to the fields in the XkbDescRec are shown in Table 2.

Table 2 Mask Bits for XkbDescRec

Mask BitXkbDescRec FieldValue

XkbAllComponentsMaskAll Fields(0x7f)

The map field of the complete Xkb keyboard description is a pointer to the Xkb client map, which is of type XkbClientMapRec:

   typedef struct {                   /* Client Map */
      unsigned char     size_types;   /* # occupied entries in types */
      unsigned char     num_types;    /* # entries in types */
      XkbKeyTypePtr     types;        /* vector of key types used by this keymap */
      unsigned short    size_syms;    /* length of the syms array */
      unsigned short    num_syms;     /* # entries in syms */
      KeySym *          syms;         /* linear 2d tables of keysyms, 1 per key */
      XkbSymMapPtr      key_sym_map;  /* 1 per keycode, maps keycode to syms */
      unsigned char *   modmap;       /* 1 per keycode, real mods bound to key */
} XkbClientMapRec, *XkbClientMapPtr;



An argument is out of range






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Time: 21:58:42 GMT, April 16, 2011