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)