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From: Robert A Duff <bobduff@shell01.TheWorld.com>
Newsgroups: comp.lang.ada
Subject: Re: Class with task destructor
Date: Wed, 30 Nov 2011 11:32:40 -0500
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Date: 2011-11-30T11:32:40-05:00
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Adam Beneschan <adam@irvine.com> writes:

> On Nov 30, 12:35�am, Simon Wright <si...@pushface.org> wrote:
>> "Rego, P." <pvr...@gmail.com> writes:
>> � �while not T_Ptr.Primary'Terminated loop
>> � � � delay 0.001;
>> � �end loop;
>
> Is it just me, or are there others who think that resorting to code
> like this is ... well, icky?

It's not just you.  ;-)

Ada should provide a way to wait for an arbitrary task, or a group of tasks,
to terminate.  Without polling.  It's quite tricky to implement, though.

Part of the problem with polling is that the delay is almost certainly
too long, or too short -- probably both!

I recently fixed an efficiency bug in a program that did something like
the above polling.  There were about 2000 tasks.  The program did its
job in a few seconds, and then at the end started waiting for all those
tasks to terminate, and that took HALF AN HOUR.

- Bob