anchor.diff:      %% SLF TODO: How does caller know if worker proc has crashed?
       %%     TODO: If filter fun or other crashes, linked server
       %%           also crashes.
  -    Self = self(),
  -    spawn_link(fun() ->
  +    StreamPid = spawn_link(fun() ->
                          F = fun(Results) ->
                                      WrappedFilter = fun({Value, Props}) -> 
                                                              FilterFun(Value, Props) == true
  
positive.code:         next_id  = NextID,
          scheduled_compaction = false,
          is_compacting = false,
          buffer_converter = Converter
      },
  
      %% Return.
  
negative.code:                                    end
                             end,
                         range(Index, Field, StartTerm, EndTerm, Size, F, Buffers, Segments),
                         Pid ! {result, '$end_of_table', Ref}
                 end),
  
      NewPids = [ #stream_range{pid=RangePid,
                                caller=Pid,
                                ref=Ref,
                                buffers=Buffers,
                                segments=Segments}
                  | State#state.stream_range_pids ],
      {reply, ok, State#state { locks=NewLocks1,
                                stream_range_pids=NewPids }};
      
  handle_call({fold, FoldFun, Acc}, _From, State) ->
      #state { buffers=Buffers, segments=Segments } = State,
  
  