How to use/obtain output from system commands (in an Ada program) ?

[reinkor <reinkor@gmail.com>]

Hi,

I am looking for a simple way to obtain output from "xmessage"
(or dialog/kdialog) in my Ada program. Any good hints?

A trivial way is to output to a file like in this test procedure:

with Interfaces.C;
with Interfaces.C.Strings;
with Ada.Text_IO, Text_IO;

procedure Test7 is
   package C renames Interfaces.C;
   use type C.char_array;
   procedure system (Source : in  C.char_array);
   pragma Import(C, system, "system");
   use Ada.Text_IO, Text_IO;
   file1 : File_Type;
begin
     system("xmessage -center Box1  -buttons label1:X,label2:y -print > choice_file1");
     Open(file1,In_File,"choice_file1");
     declare
      A : String := Get_Line(file1);
     begin
      Put(" Choice: " & A);
     end;
     Close(file1);
end Test7;

Are there more direct/better ways?

** By the way: when I run this program on Raspberry Pi 
(lastest Raspbian jessie) i get, as expected, created the file "choice_file1".
Under OpenSuse Leap 42.1, gnat-5, i get produced a file named:
"choice_file1choice_file1test7.adb". Strange?

reinert