File list on Windows and Debian

[Anders Wirzenius <anders@no.email.thanks.invalid>]

I am trying to process files in a directory. They have to be processed
in alphabetical order. With following code I get a nice sorted list on
Windows XP but not sorted at all on Linux Debian. Have I missed
something that switches the sorting on on Debian (Sarge)?

with Gnat.Directory_Operations;


with Ada.Command_Line;
with Ada.Exceptions;
with Ada.Text_IO;
with POSIX;
with POSIX_Files;
with Ada.Strings.Fixed;
procedure Ordning is

   use Ada;
   use Ada.Command_Line;
   use Ada.Text_IO;
   use POSIX;
   use POSIX_Files;

   procedure Display (Dirent : in     Directory_Entry;
                      Quit   : in out Boolean) is
      File_Name : String := To_String (Filename_Of (Dirent));
   begin
      Put_Line (File_Name);
   end Display;

   procedure Display_Directory is
      new For_Every_Directory_Entry (Action => Display);

begin
   declare
      use Gnat.Directory_Operations;
      This_Dir : Dir_Type;
      This_File: Dir_Name_Str (1..50);
      Last     : Natural;
   begin

      --
      --  First using Gnat.Directory_Operations
      --
      Put_Line ("First using Gnat.Directory_Operations");
      Put_Line ("-------------------------------------");
      Open (This_Dir, Get_Current_Dir);
      loop
         Read (This_Dir, This_File, Last);
         exit when Last=0;
         Put_Line (This_File (1..Last));
      end loop;
      Close (This_Dir);
      Put_Line ("-------------------------------------");
   end;
      --
      --  next using POSIX
      --
      Put_Line ("next using POSIX");
      Put_Line ("-------------------------------------");
   Display_Directory (To_POSIX_String ("."));
exception
   when E : others =>
      Put_Line (Exceptions.Exception_Name (E) & " - " &
                Exceptions.Exception_Message (E) & " : " &
                POSIX.Image (POSIX.Get_Error_Code));
end Ordning;


TIA
-- 
Anders