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)