task_priority/task_priority.adb


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--
--  Demonstrate Task Priority
--
--
--High:  17
--HighNative: ID=0x0B010004
-- 238
--Low:  16
--LowNative: ID=0x0B010003
-- 239


with Text_IO; use Text_IO;
with Ada.Dynamic_Priorities; use Ada.Dynamic_Priorities;
with System;
with Interfaces.C;

procedure Task_Priority is

   procedure Put_Priority is
     function getPriority return Interfaces.C.int;
     pragma Import (C, getPriority, "getPriority");
   begin
     Put_Line (Interfaces.C.int'Image (getPriority));
   end Put_Priority;

   -- I think 16 > 17 to Ada
   task Low_Task is
     pragma Priority(16);
   end Low_Task;

   task High_Task is
     pragma Priority(17);
   end High_Task;

   task body High_Task is
   begin
     Put_Line ( "High: " & System.Any_Priority'Image (Get_Priority));
     Put ( "HighNative: " );
     Put_Priority;
     loop
       delay 1.0;
       Put_Line ("High - Waking up");
     end loop;
   end High_Task;

   task body Low_Task is
     procedure empty;
     pragma Import (C, empty, "empty");
   begin
     Put_Line ( "Low: " & System.Any_Priority'Image (Get_Priority));
     Put ( "LowNative: " );
     Put_Priority;
     delay 0.1;
     loop
       empty;
     end loop;
   end Low_Task;

begin
   NULL;
end Task_Priority;