Re: Example question

[Shark8 <OneWingedShark@gmail.com>]

On 26-Oct-14 07:27, compguy45@gmail.com wrote:
> body Spreadsheet_Task is
>      begin
>          loop
>              select
>                  accept Recalculate;
>                  Do_Recalculation;
>              or
>                  accept Shutdown;
>                  exit;
>              end select;
>          end loop;
>      end Spreadsheet_Task;
>
> Tutorial says "If calls to both entries are already pending,
> one will be accepted non-deterministically." what does that
> mean? If calls are pending on bith entries it might happend
> that Shutdown is accepted and exits in which case thats not
> good solution at all
>

It means that if it enters the SELECT and there are already tasks 
waiting at the rendezvous for both entry-points then one will be chosen 
"at random". (Though I heard that some compilers /did/ have a 
deterministic behavior here.)

Perhaps you would need to add a guard to the Shutdown entry, something 
like the following: When Recalculate'Count = 0.
(I haven't really used tasking w/ guards, but I /think/ that'll work.)