XkbGetIndicatorState - Obtains the current state of the keyboard indicators

display
              connection to the X server

       device_spec
              device ID, or XkbUseCoreKbd

       state_return
              backfilled with a mask of the indicator state

       Xkb  allows  applications  to  obtain information about indicators using two different methods. The first
       method, which is similar to the core X implementation, uses a mask to specify the indicators. The  second
       method,  which  is  more suitable for applications concerned with interoperability, uses indicator names.
       The correspondence between the indicator name and the bit position in masks is as  follows:  one  of  the
       parameters  returned  from  XkbGetNamedIndicators  is  an  index  that  is the bit position to use in any
       function call that requires a mask of  indicator  bits,  as  well  as  the  indicator's  index  into  the
       XkbIndicatorRec array of indicator maps.

       XkbGetIndicatorState  queries  the display for the state of the indicators on the device specified by the
       device_spec.  For each indicator that is "turned on"  on  the  device,  the  associated  bit  is  set  in
       state_return.   If  a  compatible  version  of  the  Xkb  extension  is  not  available  in  the  server,
       XkbGetIndicatorState returns a BadMatch error. Otherwise, it sends the request to the  X  server,  places
       the  state  of  the  indicators  into  state_return,  and  returns  Success.  Thus  the value reported by
       XkbGetIndicatorState is identical to the value reported by the core protocol.

BadMatch       A compatible version of Xkb was not available in the server or  an  argument  has  correct
                      type and range, but is otherwise invalid

       XkbGetIndicatorState - Obtains the current state of the keyboard indicators

XkbGetNamedIndicators(3)

X Version 11                                      libX11 1.8.12                          XkbGetIndicatorState(3)

StatusXkbGetIndicatorState(Display*display,unsignedintdevice_spec,unsignedintstate_return);