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From: Sebastian Hanigk <hanigk@in.tum.de>
Newsgroups: comp.lang.ada
Subject: Re: [Ravenscar] run tasks on events
Date: Fri, 30 May 2008 13:17:42 +0200
Organization: [posted via] Leibniz-Rechenzentrum, Muenchen (Germany)
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Date: 2008-05-30T13:17:42+02:00
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Niklas Holsti <niklas.holsti@tidorum.invalid> writes:

Hello!

> Since the Ravenscar profile contains the restriction
> No_Task_Termination, by LRM D.7.15(1/2) it is implementation defined
> what happens when a Ravenscar task terminates due to an unhandled
> exception or for other reasons. It may be reported or signalled in
> some way, or not.

I'm using GNAT 4.0.2 on Solaris 10 (AMD); it seems that my second test
task has silently died.

> [suspension objects per task]
>
> The "elegance" of this solution is subjective, of course, but I don't
> find it very ugly to have a different object for each task; it even
> makes it easier to select the subset of tasks that should become
> active.

I have to confess that I was rather enthralled with the simplicity of
the signal/scheduler method ;-)

The difference most likely is only the shift in responsibility: in HAL/S
the programmer simply specifies when to activate tasks, in Ada I have to
do the bookkeeping myself (but I do gain more flexibility).


Thanks for your advice!

Sebastian