anchor.diff:      {{response_header, string:to_lower(lists:reverse(Var))}, Col+2, Rest};
   parse_accesslog_var([$r,$e,$a,$l,$},$a|Rest], Col, []) ->
       {real_remote_ip, Col+6, Rest};
  +parse_accesslog_var([$r,$e,$a,$l,$},$h|Rest], Col, []) ->
  +    {real_remote_host, Col+6, Rest};
   parse_accesslog_var([C|Rest], Col, Var) ->
       parse_accesslog_var(Rest, Col+1, [C|Var]).
   
  
positive.code:                  {Ip,_,_,OutH,_}=Data, Msg) ->
      Msg1 = case check_cond(Cond, OutH#outh.status) of
                 true  -> [format_host(Ip)|Msg];
                 false -> [$-|Msg]
             end,
      format_accesslog(Rest, ServerName, RevPx, Data, Msg1);
  
negative.code:     try
          Ip = yaws_logger_netutils:parse_ip(HostName),
          format_real_ip(Ip, InH, RevPx)
      catch
          _:_ ->
              HostName
      end.
  
  format_real_host(Ip, InH, RevPx) when is_tuple(Ip) ->
      case is_whitelisted_revproxy(Ip, RevPx) of
          true ->
              case yaws:split_sep(InH#headers.x_forwarded_for, $,) of
                  [FirstIp|_Proxies] -> format_host(FirstIp);
                  []                 -> format_host(Ip)
              end;
          false ->
              format_host(Ip)
      end;
  format_real_host(unknown, _InH, _RevPx) ->
      "unknown";
  format_real_host(undefined, _InH, _RevPx) ->
      "unknown";
  format_real_host(HostName, InH, RevPx) ->
      try
          Ip = yaws_logger_netutils:parse_ip(HostName),
          format_real_host(Ip, InH, RevPx)
      catch
          _:_ ->
              HostName
  