XkbGetVirtualMods
Section: XKB FUNCTIONS (3)
Updated: libX11 1.6.4
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NAME
XkbGetVirtualMods - Obtain a subset of the virtual modifier bindings (the vmods
array) in a keyboard description
SYNOPSIS
-
Status XkbGetVirtualMods
(Display *dpy,
unsigned int which,
XkbDescPtr xkb);
ARGUMENTS
- - dpy
-
- connection to server
- - which
-
mask indicating virtual modifier bindings to get
- - xkb
-
Xkb description where results will be placed
DESCRIPTION
XkbGetVirtualMods
sends a request to the server to obtain the
vmods
entries for the virtual modifiers specified in the mask,
which,
and waits for a reply.
Virtual modifiers are named by converting their string name to an X Atom and storing the Atom in the
names.vmods
array in an XkbDescRec structure. The position of a name Atom in the
names.vmods
array defines the bit position used to represent the virtual modifier and also the index used when
accessing virtual modifier information in arrays: the name in the i-th (0 relative) entry of
names.vmods
is the i-th virtual modifier, represented by the mask (1<<i). Throughout Xkb, various functions have
a parameter that is a mask representing virtual modifier choices. In each case, the i-th bit (0
relative) of the mask represents the i-th virtual modifier.
To set the name of a virtual modifier, use
XkbSetNames,
using XkbVirtualModNamesMask in
which
and the name in the
xkb
argument; to retrieve indicator names, use
XkbGetNames.
For each bit set in
which, XkbGetVirtualMods
updates the corresponding virtual modifier definition in the
server->vmods
array of
xkb.
The
xkb
parameter must be a pointer to a valid Xkb keyboard description. If successful,
XkbGetVirtualMods
returns Success.
Virtual Modifier Names and Masks
Virtual modifiers are named by converting their string name to an X Atom and
storing the Atom in the
names.vmods
array in an XkbDescRec structure. The position of a name Atom in the
names.vmods
array defines the bit position used to represent the virtual modifier and also
the index used when accessing virtual modifier information in arrays: the name
in the i-th (0 relative) entry of
names.vmods
is the i-th virtual modifier, represented by the mask (1<<i). Throughout Xkb,
various functions have a parameter that is a mask representing virtual modifier
choices. In each case, the i-th bit (0 relative) of the mask represents the i-th
virtual modifier.
To set the name of a virtual modifier, use
XkbSetNames,
using XkbVirtualModNamesMask in
which
and the name in the
xkb
argument; to retrieve indicator names, use
XkbGetNames.
If the
server
map has not been allocated in the
xkb
parameter,
XkbGetVirtualMods
allocates and initializes it before obtaining the virtual modifier bindings.
If the server does not have a compatible version of Xkb, or the Xkb extension
has not been properly initialized,
XkbGetVirtualMods
returns BadMatch. Any errors in allocation cause
XkbGetVirtualMods
to return BadAlloc.
RETURN VALUES
- Success
-
The
XkbGetVirtualMods
function returns Success when it successfully updates the corresponding virtual modifier definition
in the
server->vmods
array of
xkb.
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 1.
Table 1 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)
|
DIAGNOSTICS
- BadAlloc
-
Unable to allocate storage
- BadMatch
-
A compatible version of Xkb was not available in the server or an argument has
correct type and range, but is otherwise invalid
SEE ALSO
XkbGetNames(3),
XkbSetNames(3)
Index
- NAME
-
- SYNOPSIS
-
- ARGUMENTS
-
- DESCRIPTION
-
- RETURN VALUES
-
- STRUCTURES
-
- DIAGNOSTICS
-
- SEE ALSO
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