anchor.diff:  %% @spec last(erlang:iodata()) -> { ok, Response }  |  
   %%   { error, Reason } 
   %%  Reason = iolist()
  -%%  Response = iolist()
  +%%  Response = integer()
   %% @doc    Return the date of the last data sample in an RRD. Check 
   %% [http://oss.oetiker.ch/rrdtool/doc/rrdlast.en.html rrdlast]
  -last       (Args) when is_list(Args) -> do(last,       Args).
  +last       (Args) when is_list(Args) -> 
  +  case do(last,       Args) of
  +    { error, Reason } -> { error, Reason };
  +    { ok, [[Response]] } -> { ok, erlang:list_to_integer(Response) }
  +  end.
   
   %% @spec lastupdate(erlang:iodata()) -> { ok, Response }  |  
   %%   { error, Reason } 
  
positive.code:             lists:seq(1, Steps)
            )
          end,
          % make a graph!! :)
          fun() -> 
            { ok, _ } = erlrrd:graph([
  
negative.code: %% @spec first(erlang:iodata()) -> { ok, Response }  |  
  %%   { error, Reason } 
  %%  Reason = iolist()
  %%  Response = integer()
  %% @doc Return the date of the first data sample in an RRA within an
  %%       RRD. Check 
  %% [http://oss.oetiker.ch/rrdtool/doc/rrdfirst.en.html rrdfirst]
  first       (Args) when is_list(Args) -> 
    case do(first,       Args) of
      { error, Reason } -> { error, Reason };
      { ok, [[Response]] } -> { ok, erlang:list_to_integer(Response) }
    end.
  
  %% @spec info(erlang:iodata()) -> { ok, Response }  |  
  %%   { error, Reason } 
  