Provided by: libx11-doc_1.6.9-2ubuntu1_all bug


       XkbNoteDeviceChanges - Note device changes reported in an XkbExtensionDeviceNotify event


       void  XkbNoteDeviceChanges  (XkbDeviceChangesPtr  old, XkbExtensionDeviceNotifyEvent *new,
              unsigned int wanted);


       - old  structure tracking state changes

       - new  event indicating state changes

       - wanted
              mask indicating changes to note


       The wanted field specifies the changes that should be noted in old, and is composed of the
       bitwise  inclusive  OR  of  one or more of the masks from Table 1. The reason field of the
       event in new indicates the types of changes the event is reporting.   XkbNoteDeviceChanges
       updates  the XkbDeviceChangesRec specified by old with the changes that are both specified
       in wanted and contained in new->reason.

                                Table 1 XkbDeviceInfoRec Mask Bits
       Name                         XkbDeviceInfoRec Value     Capability If Set
                                    Fields Effected
       XkbXI_KeyboardsMask                           (1L <<0) Clients can use all
                                                              Xkb requests and events
                                                              with KeyClass devices
                                                              supported by the input
                                                              device extension.

       XkbXI_ButtonActionsMask       num_btns        (1L <<1) Clients can assign key
                                     btn_acts                 actions to buttons
                                                              non-KeyClass input
                                                              extension devices.

       XkbXI_IndicatorNamesMask      leds->names     (1L <<2) Clients can assign
                                                              names to indicators on
                                                              non-KeyClass input
                                                              extension devices.

       XkbXI_IndicatorMapsMask       leds->maps      (1L <<3) Clients can assign
                                                              indicator maps to
                                                              indicators on
                                                              non-KeyClass input
                                                              extension devices.

       XkbXI_IndicatorStateMask      leds->state     (1L <<4) Clients can request
                                                              the status of indicators
                                                              on non-KeyClass input
                                                              extension devices.

       XkbXI_IndicatorsMask          sz_leds         (0x1c)   XkbXI_IndicatorNamesMask |
                                     num_leds                 XkbXI_IndicatorMapsMask |
                                     leds->*                  XkbXI_IndicatorStateMask

       XkbXI_UnsupportedFeaturesMask unsupported     (1L <<15)

       XkbXI_AllDeviceFeaturesMask   Those selected  (0x1e)   XkbXI_IndicatorsMask |
                                     by Value Column          XkbSI_ButtonActionsMask

       XkbXI_AllFeaturesMask         Those selected  (0x1f)   XkbSI_AllDeviceFeaturesMask |
                                     by Value Column          XkbSI_KeyboardsMask

       XkbXI_AllDetailsMask          Those selected  (0x801f) XkbXI_AllFeaturesMask |
                                     by Value column          XkbXI_UnsupportedFeaturesMask

       To update a local copy of the state and configuration of an X input extension device  with
       the    changes    previously    noted    in    an   XkbDeviceChangesRec   structure,   use


       Changes to an Xkb extension device may be tracked by listening to XkbDeviceExtensionNotify
       events and accumulating the changes in an XkbDeviceChangesRec structure. The changes noted
       in the structure may then be used in subsequent  operations  to  update  either  a  server
       configuration  or  a  local  copy  of  an  Xkb extension device configuration. The changes
       structure is defined as follows:

       typedef struct _XkbDeviceChanges {
           unsigned int         changed;       /∗ bits indicating what has changed */
           unsigned short       first_btn;     /∗ number of first button which changed, if any */
           unsigned short       num_btns;      /∗ number of buttons that have changed */
           XkbDeviceLedChangesRec leds;
       } XkbDeviceChangesRec,*XkbDeviceChangesPtr;