anchor.diff:      {State#state{current_pos=NextF(Tab, Key), limit=counter_dec(Limit, RecN)}, RecL, RecN};
   %% disk_log
   prep_fold(#state{status=spec_disk_log, limit=0} = State) ->
  -    finish_fold(State);
  +    {State, done};
   prep_fold(#state{status=spec_disk_log, current_pos=Cont0, limit=Limit} = State) ->
       case disk_log:chunk(dlog, Cont0) of
           eof ->
  
positive.code:            fold_fun=FoldFun, limit=Limit, current_pos=FirstF(Tab),
             spec=ds:new()};
  %% Initialize a fold through a disk_log file. Useful for Mnesia .DCD and .DCL
  init(Filename, FieldSpec0, Limit) ->
      ds_records:init(),
      {ok, dlog} = disk_log:open([ {name, dlog}
                                 , {file, Filename}
  
negative.code:             end;
          {done, AccRecN} ->
              ?debug("master: got 'done', AccRecN=~p", [AccRecN]),
              NextPid ! get_result,
              State = finish_fold(State0),
              Progress = ds_progress:update(Progress0, Spec0, AccRecN),
              procs_master_loop(State#state{progress=Progress});
          {result,_Pid, SlaveSpec} ->
              ?debug("master: result from ~p, n_procs: ~p", [_Pid, NProcs]),
              Spec = ds:join(Spec0, SlaveSpec),
  