code: func (l *lockServer) Expired(args *dsync.LockArgs, reply *bool) error {
  	l.mutex.Lock()
  	defer l.mutex.Unlock()
  	if lri, ok := l.lockMap[args.Resource]; ok {
  		// Check whether uid is still active for this name
  		for _, entry := range lri {
  			if entry.uid == args.UID {
  				*reply = false // When uid found, lock is still active so return not expired
  				return nil
  			}
  		}
  	}
  	// When we get here, lock is no longer active due to either args.Resource being absent from map
  	// or uid not found for given args.Resource
  	*reply = true
  	return nil
  }
docs: // Expired - rpc handler for expired lock status.