anchor.diff:  
   %% report tracing events from other modules
   -export([log_send/4]).
  --export([log_info/3]).
  +-export([log_info/2, log_info/3]).
   -export([log_recv/4]).
   -export([epidemic_reply_msg/4]).
   
  
positive.code:     end,
      epidemic_reply_msg(PState, From, To, Msg).
  
  -spec log_info(passed_state(), anypid(), term()) -> ok.
  log_info(PState, FromPid, Info) ->
      From = normalize_pidinfo(FromPid),
  
negative.code: %% sample call sequence to get a tx trace:
  %% tex traces have to be relatively short, so paste all at once to the
  %% erlang shell.
  %% api_tx:write("b", 1). trace_mpath:start(). api_tx:write("a", 1). trace_mpath:stop(). T = trace_mpath:get_trace(). trace_mpath:to_texfile(T, "trace2.tex").
  
  -spec to_texfile(trace(), file:name()) -> ok | {error, file:posix() | badarg | terminated}.
  to_texfile(Trace, Filename) ->
  