Re: GNAT.Serial_Communication and Streams

["Jeffrey R. Carter" <spam.jrcarter.not@spam.not.acm.org>]

On 11/22/2015 02:40 PM, rrr.eee.27@gmail.com wrote:
>    procedure Send_Command (Cmd : String)
>    is
>       Output_Max_Length : constant Ada.Streams.Stream_Element_Offset := 50;
>       Output : Ada.Streams.Stream_Element_Array (1 .. Output_Max_Length);
>    begin
>       for I in 1 .. Cmd'Length loop
>          Output (Ada.Streams.Stream_Element_Offset(I)) := Character'Pos(Cmd (Cmd'First + I - 1));
>       end loop;
>       Output (Cmd'Length+1) := Character'Pos(ASCII.LF);

What happens when Cmd'Length > 49?

>       GNAT.Serial_Communication.Write (P, Output(1..Cmd'Length+1));
>    end Send_Command;
> 
> 
> That works but feels completely strange to me. I'm sure that I'm missing something here. There must be an easier way to fill the output buffer with a standard string.

What about

procedure Send (Cmd : in String) is
   Local  : constant String := Cmd & Ada.Characters.Latin_1.LF;
   Output : constant Ada.Streams.Stream_Element_Array (1 .. Local'Length);
   pragma Import (Ada, Output);
   for Output'Address use Local'Address;
begin -- Send
   GNAT.Serial_Communication.Write (P, Output)?
end Send;

?

-- 
Jeff Carter
"When danger reared its ugly head, he bravely
turned his tail and fled."
Monty Python and the Holy Grail
60