anchor.diff:                    %                              {subdir, io_lib:format("~s/Trace", [EvalDir])}]),
                     
                     reset(),
  +                  MPFile =/= null andalso MPFileWriter ! MP,
                     MP
             end),
       
  
positive.code:     % WRITE LINE
      EPFile =/= null andalso
          rr_eval_export:write_ds(EPFile, {[], [tuple_to_list(EP)]}),
      MPFile =/= null andalso
          rr_eval_export:write_ds(MPFile, {[], [tuple_to_list(Row) || Row <- MPList]}),
      
      pair_sync(Setup, Options, IncParam, IncSize, StepCount - 1, {[EP | AccEP], lists:append(MPList, AccMP), EPId + 1}).
  
  
negative.code: %    EvalDir = proplists:get_value(eval_dir, Options, "../"),
  %    {Hour, Min, Sec} = proplists:get_value(eval_time, Options, {0, 0, 0}),
      
      % spawn a separate process for writing measure points:
      Self = self(),
      MPFileWriter =
          if MPFile =/= null ->
                 erlang:spawn_link(
                   fun() ->
                           util:for_to_ex(
                             1, EvalRepeats,
                             fun(_I) ->
                                     receive MPRow ->
                                                 rr_eval_export:write_ds(
                                                   MPFile, {[], [tuple_to_list(MPRow)]})
                                     end
                             end),
                           Self ! mp_write_done
                   end);
             true -> nopid
          end,
  
      MPList =
          util:for_to_ex(
            1, EvalRepeats,
  