anchor.diff:  
   %% See 'Example usage' section of ../README.md
   
  -%% NOTE: PidSpec = pid() | [pid()] | existing | new | all
  +
  +%% NOTE: Mode::pidspec() = custom_trace_flags() |
  +%%                         pid() | [pid()] | existing | new | all
  +%%  custom_trace_flags() = [custom_trace_flag()]
  +%%   custom_trace_flag() = 'global_calls_only'.
   
   write_trace(Mode, IntermediateFile, PidSpec, M, F, A) ->
       write_trace2(normal, Mode, IntermediateFile, PidSpec, M, F, A).
  
positive.code:     start_trace2(_Tracer, PidSpec, Mode, MatchSpec).
  
  start_trace2(_Tracer, PidSpec, Mode, MatchSpec) ->
      _X2b = dbg:tpl('_', '_', MatchSpec),
      io:format("X2b ~p\n", [_X2b]),
      if is_list(PidSpec) ->
              [dbg:p(PS, trace_flags(Mode)) || PS <- PidSpec];
  
negative.code: 
  trace_flags(not_running) ->
      [call, arity, return_to, timestamp];
  trace_flags(normal) ->
      [call, arity, return_to, timestamp, running];
  trace_flags(normal_with_children) ->
      [call, arity, return_to, timestamp, running, set_on_spawn];
  trace_flags(like_fprof) ->
      [call, arity, return_to, timestamp, running, set_on_spawn, garbage_collection];
  trace_flags(List) when is_list(List) ->
      io:format(user, "\nWARNING: we assume that you know what you're doing "
                "when\nspecifying trace_flags(~w)\n", [List]),
      List -- custom_trace_flags().
  
  custom_trace_flags() ->
      [global_calls_only].
  
  entry_to_iolist({M, F, A}) ->
      [atom_to_binary(M, utf8), <<":">>, atom_to_binary(F, utf8), <<"/">>, integer_to_list(A)];
  