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From: Natasha Kerensikova <lithiumcat@instinctive.eu>
Newsgroups: comp.lang.ada
Subject: Re: Termination of tasks waiting on a protected queue
Date: Mon, 19 May 2014 07:28:02 +0000 (UTC)
Organization: A noiseless patient Spider
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Date: 2014-05-19T07:28:02+00:00
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Hello,

On 2014-05-18, Brad Moore <brad.moore@shaw.ca> wrote:
> I was faced with a similar problem in the non-Ravenscar task pools in 
> Paraffin.
>
> I did not want the programmer to have to call some protected subprogram 
> to trigger the task pool to terminate. I also did not want to have to 
> wait for a timeout to expire before the application could exit. I wanted 
> it to be immediate.

That looks indeed very similar to what I had in mind.

> So in your example, it might look something like;

Your example is exactly what I was looking for when posting here.
Thanks a lot!

However I'm considering merging the functionalities of Worker_Idle,
Is_Empty and Get_Next into a single protected procedure. Something like

      procedure Get_Next
        (Job : out Job_Description;
         Idle : out Boolean) is
      begin
         if List.Is_Empty then
            Idle := True;
            Queue.Idle := True;
         else
            Job := List.First_Element;
            List.Delete_First;
         end if;
     end Get_Next;

But then the solution is a bit more difficult to scale to multiple
worker tasks. Maybe with an array of Boolean for Idle. Fortunately I
don't have to deal with that for now.


Thanks again for the solution,
Natasha