Manual Reference Pages  - XkbSetCompatMap (3)


XkbSetCompatMap - Modify the server’s compatibility map




Bool XkbSetCompatMap (Display *display, unsigned int which, XkbDescPtr xkb, Bool update_actions);    


- display
  connection to server
- which mask of compat map components to set
- xkb source for compat map components
- update_actions
  True => apply to server’s keyboard map


To modify the server’s compatibility map, first modify a local copy of the Xkb compatibility map, then call XkbSetCompatMap. You may allocate a new compatibility map for this purpose using XkbAllocCompatMap. You may also use a compatibility map from another server, although you need to adjust the device_spec field in the XkbDescRec accordingly. Note that symbol interpretations in a compatibility map ( sym_interpret, the vector of XkbSymInterpretRec structures) are also allocated using this same function.

XkbSetCompatMap copies compatibility map information from the keyboard description in xkb to the server specified in display device_spec field of xkb. Unless you have specifically modified this field, it is the default keyboard device. which specifies the compatibility map components to be set, and is an inclusive OR of the bits shown in Table 1.

Table 1 Compatibility Map Component Masks
XkbSymInterpMask(1<<0)Symbol interpretations
XkbGroupCompatMask(1<<1)Group maps
XkbAllCompatMask(0x3)All compatibility map components

After updating its compatibility map for the specified device, if update_actions is True, the server applies the new compatibility map to its entire keyboard for the device to generate a new set of key semantics, compatibility state, and a new core keyboard map. If update_actions is False, the new compatibility map is not used to generate any modifications to the current device semantics, state, or core keyboard map. One reason for not applying the compatibility map immediately would be if one server was being configured to match another on a piecemeal basis; the map should not be applied until everything is updated. To force an update at a later time, use XkbSetCompatMap specifying which as zero and update_actions as True.

XkbSetCompatMap returns True if successful and False if unsuccessful. The server may report problems it encounters when processing the request subsequently via protocol errors.


True The XkbSetCompatMap function returns True if successful.
False The XkbSetCompatMap function returns False if unsuccessful.


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 XkbSymInterpretRec structure specifies a symbol interpretation:

typedef struct { KeySym sym; /* keysym of interest or NULL */ unsigned char flags; /* XkbSI_AutoRepeat, XkbSI_LockingKey */ unsigned char match; /* specifies how mods is interpreted */ unsigned char mods; /* modifier bits, correspond to eight real modifiers */ unsigned char virtual_mod; /* 1 modifier to add to key virtual mod map */ XkbAnyAction act; /* action to bind to symbol position on key */ } XkbSymInterpretRec,*XkbSymInterpretPtr;



X Version 11 XkbSetCompatMap (3) libX11 1.5.0
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