anchor.diff:  fmt(Fmt, Args,  D=#data{writer=Write,acc=Acc}) ->
       D#data{acc = Write(io_lib:format(Fmt, Args), Acc)}.
   
  +ts({_,_,Usec}=Now) ->
  +    {_Date,{HH,MM,SS}} = calendar:now_to_local_time(Now),
  +    io_lib:format("~.2.0w:~.2.0w:~.2.0w.~.6.0w",[HH,MM,SS,Usec]);
  +ts(_) ->
  +    "-".
   %%%----------------------------------------------------------------
   setup_tracer(Write, MangleArg) ->
       Handler = fun(Arg, D) ->
  
positive.code:     ok.
  
  %%%----------------------------------------------------------------
  shrink_bin(B) when is_binary(B), size(B)>100 -> {'*** SHRINKED BIN',
  						 size(B),
  						 element(1,split_binary(B,20)),
  						 '...',
  						 element(2,split_binary(B,size(B)-20))
  						};
  shrink_bin(L) when is_list(L) -> lists:map(fun shrink_bin/1, L);
  shrink_bin(T) when is_tuple(T) -> list_to_tuple(shrink_bin(tuple_to_list(T)));
  
negative.code: 				is_function(MangleArg,1) ->
      catch dbg:start(),
      setup_tracer(Write, MangleArg),
      dbg:p(new,[c,timestamp]),
      dbg_ssh_messages().
  
  dbg_ssh_messages() ->
      dbg:tp(ssh_message,encode,1, x),
      dbg:tp(ssh_message,decode,1, x),
      dbg:tpl(ssh_transport,select_algorithm,3, x),
      dbg:tp(ssh_transport,hello_version_msg,1, x),
      dbg:tp(ssh_transport,handle_hello_version,1, x).
     
  %%%----------------------------------------------------------------
  stop() ->
      dbg:stop().
  
  %%%================================================================
  msg_formater({trace_ts,Pid,call,{ssh_message,encode,[Msg]},TS}, D) ->
      fmt("~n~s SEND ~p ~s~n", [ts(TS),Pid,wr_record(shrink_bin(Msg))], D);
  msg_formater({trace_ts,_Pid,return_from,{ssh_message,encode,1},_Res,_TS}, D) -> 
      D;
  	
  msg_formater({trace_ts,_Pid,call,{ssh_message,decode,_},_TS}, D) ->
      D;
  msg_formater({trace_ts,Pid,return_from,{ssh_message,decode,1},Msg,TS}, D) -> 
      fmt("~n~s ~p RECV ~s~n", [ts(TS),Pid,wr_record(shrink_bin(Msg))], D);
  	
  msg_formater({trace_ts,_Pid,call,{ssh_transport,select_algorithm,_},_TS}, D) ->
      D;
  msg_formater({trace_ts,Pid,return_from,{ssh_transport,select_algorithm,3},{ok,Alg},TS}, D) ->
      fmt("~n~s ~p ALGORITHMS~n~s~n", [ts(TS),Pid, wr_record(Alg)], D);
  
  msg_formater({trace_ts,_Pid,call,{ssh_transport,hello_version_msg,_},_TS}, D) ->
      D;
  msg_formater({trace_ts,Pid,return_from,{ssh_transport,hello_version_msg,1},Hello,TS}, D) -> 
      fmt("~n~s ~p TCP SEND HELLO~n  ~p~n", [ts(TS),Pid,lists:flatten(Hello)], D);
  
  msg_formater({trace_ts,Pid,call,{ssh_transport,handle_hello_version,[Hello]},TS}, D) ->
      fmt("~n~s ~p RECV HELLO~n  ~p~n", [ts(TS),Pid,lists:flatten(Hello)], D);
  msg_formater({trace_ts,_Pid,return_from,{ssh_transport,handle_hello_version,1},_,_TS}, D) -> 
      D;
  
  msg_formater({trace_ts,Pid,send,{tcp,Sock,Bytes},Pid,TS}, D) ->
      fmt("~n~s ~p TCP SEND on ~p~n ~p~n", [ts(TS),Pid,Sock, shrink_bin(Bytes)], D);
  
  msg_formater({trace_ts,Pid,send,{tcp,Sock,Bytes},Dest,TS}, D) ->
      fmt("~n~s ~p TCP SEND from ~p TO ~p~n ~p~n", [ts(TS),Pid,Sock,Dest, shrink_bin(Bytes)], D);
  
  msg_formater({trace_ts,Pid,send,ErlangMsg,Dest,TS}, D) ->
      fmt("~n~s ~p ERL MSG SEND TO ~p~n ~p~n", [ts(TS),Pid,Dest, shrink_bin(ErlangMsg)], D);
  
  
  msg_formater({trace_ts,Pid,'receive',{tcp,Sock,Bytes},TS}, D) ->
      fmt("~n~s ~p TCP RECEIVE on ~p~n ~p~n", [ts(TS),Pid,Sock,shrink_bin(Bytes)], D);
  
  msg_formater({trace_ts,Pid,'receive',ErlangMsg,TS}, D) ->
      fmt("~n~s ~p ERL MSG RECEIVE~n ~p~n", [ts(TS),Pid,shrink_bin(ErlangMsg)], D);
  
  
  msg_formater(M, D) ->
  