Tribblix: manual page: XkbGetMap.3

XkbGetMap(3) XKB FUNCTIONS XkbGetMap(3)

NAME

XkbGetMap - Allocate an XkbDescRec structure and populate it with the
server's keyboard client map and server map

SYNOPSIS

XkbDescPtr XkbGetMap (Display *display, unsigned int which, unsigned
int device_spec);

ARGUMENTS

display
connection to X server

which mask selecting subcomponents to populate

device_spec
device_id, or XkbUseCoreKbd

DESCRIPTION

Xkb provides two functions to obtain the keyboard mapping components
from the server. The first function, XkbGetMap, allocates an
XkbDescRec structure, retrieves mapping components from the server,
and stores them in the XkbDescRec structure it just allocated. The
second function, XkbGetUpdatedMap, retrieves mapping components from
the server and stores them in an XkbDescRec structure that has
previously been allocated.

To allocate an XkbDescRec structure and populate it with the server's
keyboard client map and server map, use XkbGetMap. XkbGetMap is
similar to XkbGetKeyboard, but is used only for obtaining the address
of an XkbDescRec structure that is populated with keyboard mapping
components. It allows finer control over which substructures of the
keyboard mapping components are to be populated. XkbGetKeyboard
always returns fully populated components, while XkbGetMap can be
instructed to return a partially populated component.

The which mask is a bitwise inclusive OR of the masks defined in
Table 14.1. Only those portions of the keyboard server map and the
keyboard client maps that are specified in which are allocated and
populated.

In addition to allocating and obtaining the server map and the client
map, XkbGetMap also sets the device_spec, the min_key_code, and
max_key_code fields of the keyboard description.

XkbGetMap is synchronous; it queries the server for the desired
information, waits for a reply, and then returns. If successful,
XkbGetMap returns a pointer to the XkbDescRec structure it allocated.
If unsuccessful, XkbGetMap returns NULL. When unsuccessful, one of
the following protocol errors is also generated: BadAlloc (unable to
allocate the XkbDescRec structure), BadValue (some mask bits in which
are undefined), or BadImplementation (a compatible version of the Xkb
extension is not available in the server). To free the returned data,
use XkbFreeKeyboard.

Xkb also provides convenience functions to get partial component
definitions from the server. These functions are specified in the
"convenience functions" column in Table 1. Refer to the sections
listed in the table for more information on these functions.

Table 1 Xkb Mapping Component Masks
and Convenience Functions
------------------------------------------------------------------------------------------------
Mask Value Map Fields Convenience
Functions
------------------------------------------------------------------------------------------------
XkbKeyTypesMask (1<<0) client types XkbGetKeyTypes
size_types XkbResizeKeyType
num_types XkbCopyKeyType XkbCopyKeyTypes
XkbKeySymsMask (1<<1) client syms XkbGetKeySyms XkbResizeKeySyms
size_syms XkbChangeTypesOfKey
num_syms
key_sym_map
XkbModifierMapMask (1<<2) client modmap XkbGetKeyModifierMap
XkbExplicitComponentsMask (1<<3) server explicit XkbGetKeyExplicitComponents
XkbKeyActionsMask (1<<4) server key_acts XkbGetKeyActions
acts XkbResizeKeyActions
num_acts
size_acts
XkbKeyBehaviorsMask (1<<5) server behaviors XkbGetKeyBehaviors
XkbVirtualModsMask (1<<6) server vmods XkbGetVirtualMods
XkbVirtualModMapMask (1<<7) server vmodmap XkbGetVirtualModMap

Xkb defines combinations of these masks for convenience:

#define XkbResizableInfoMask (XkbKeyTypesMask)
#define XkbAllClientInfoMask (XkbKeyTypesMask | XkbKeySymsMask |
XkbModifierMapMask)
#define XkbAllServerInfoMask (XkbExplicitComponentsMask |
XkbKeyActionsMask |
XkbKeyBehaviorsMask |
XkbVirtualModsMask |
XkbVirtualModMapMask)
#define XkbAllMapComponentsMask XkbAllClientInfoMask |
XkbAllServerInfoMask)

Key types, symbol maps, and actions are all interrelated: changes in
one require changes in the others. The convenience functions make it
easier to edit these components and handle the interdependencies.

STRUCTURES

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 Bit XkbDescRec Field Value
--------------------------------------------------
XkbControlsMask ctrls (1L<<0)
XkbServerMapMask server (1L<<1)
XkbIClientMapMask map (1L<<2)
XkbIndicatorMapMask indicators (1L<<3)
XkbNamesMask names (1L<<4)
XkbCompatMapMask compat (1L<<5)
XkbGeometryMask geom (1L<<6)
XkbAllComponentsMask All Fields (0x7f)

NAME

SYNOPSIS

ARGUMENTS

DESCRIPTION

STRUCTURES

SEE ALSO