anchor.diff:  	StartStep = MaxFiles div 2,
   	start_binary_tree(Log, Start, MaxFiles, start, 0, StartStep, StartStep).
   %% @hidden
  -start_binary_tree(_Log, _Start, NumFiles,
  +start_binary_tree(Log, Start, NumFiles,
   		LastCont, _LastStep, _StepSize, NumFiles) ->
  +%	LastCont;
  +	{1, [Event]} = last(Log, 1),
  +	TimeStamp = element(1, Event),
  +	case TimeStamp >= Start of
  +		true ->
  +			LastCont;
  +		false ->
  +			eof
  +	end;
  +start_binary_tree(_Log, _Start, _NumFiles,
  +		LastCont, _LastStep, _StepSize, -1) ->
  +%	eof;
   	LastCont;
  -start_binary_tree(_Log, _Start, _NumFiles,
  -		_LastCont, _LastStep, _StepSize, -1) ->
  -	eof;
   start_binary_tree(Log, Start, NumFiles, LastCont, LastStep, StepSize, Step) ->
  -%	case disk_log:chunk_step(Log, start, Step - 1) of
   	case disk_log:chunk_step(Log, start, Step) of
   		{ok, NewCont} ->
   			start_binary_tree(Log, Start, NumFiles, LastCont, LastStep,
   					StepSize, Step, NewCont, disk_log:chunk(Log, NewCont, 1));
   		{error, end_of_log} ->
  -erlang:display({?MODULE, ?LINE, LastCont}),
  +%			eof;
   			LastCont;
   		{error, Reason} ->
   			{error, Reason}
  
positive.code: start_binary_tree(_Log, Start, _NumFiles, _LastCont, LastStep, 1,
  		Step, NewCont, {_, [R]}) when element(1, R) < Start,
  		LastStep == (Step + 1) ->
  erlang:display({?MODULE, ?LINE, element(1, R), Start, LastStep, Step}),
  	NewCont;
  start_binary_tree(Log, Start, NumFiles, _LastCont, _LastStep, 1,
  		Step, NewCont, {_, [R]}) when element(1, R) < Start ->
  erlang:display({?MODULE, ?LINE, element(1, R), Start}),
  	start_binary_tree(Log, Start, NumFiles, NewCont, Step, 1, Step + 1);
  start_binary_tree(Log, Start, NumFiles, _LastCont, _LastStep, StepSize,
  		Step, NewCont, {_, [R]}) when element(1, R) < Start ->
  	NewStepSize = StepSize div 2,
  erlang:display({?MODULE, ?LINE, element(1, R), Start, StepSize, NewStepSize}),
  	start_binary_tree(Log, Start, NumFiles, NewCont, Step,
  			NewStepSize, Step + NewStepSize);
  start_binary_tree(_Log, Start, _NumFiles, LastCont, LastStep, 1,
  		Step, _NewCont, {_, [R]}) when element(1, R) >= Start,
  		LastStep == (Step - 1) ->
  erlang:display({?MODULE, ?LINE, element(1, R), Start, LastStep, Step}),
  	LastCont;
  start_binary_tree(Log, Start, NumFiles, _LastCont, _LastStep, 1,
  		Step, NewCont, {_, [R]}) when element(1, R) >= Start ->
  erlang:display({?MODULE, ?LINE, element(1, R), Start}),
  	start_binary_tree(Log, Start, NumFiles, NewCont, Step, 1, Step - 1);
  start_binary_tree(Log, Start, NumFiles, _LastCont, _LastStep, StepSize,
  		Step, NewCont, {_, [R]}) when element(1, R) >= Start ->
  	NewStepSize = StepSize div 2,
  erlang:display({?MODULE, ?LINE, element(1, R), Start, StepSize, NewStepSize, Step}),
  	start_binary_tree(Log, Start, NumFiles, NewCont, Step,
  			NewStepSize, Step - NewStepSize);
  start_binary_tree(_, _, _, _, _, _, _, _, {error, Reason}) ->
  
negative.code: %%
  acct_query(Continuation, Start, End, Protocol, Types, MatchSpec) ->
  	MFA = {?MODULE, acct_query, [Protocol, Types, MatchSpec]},
  	query_log(Continuation, Start, End, log_name(acct_log_name), MFA).
  
  -spec auth_open() -> Result
  