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From: Robert A Duff <bobduff@shell01.TheWorld.com>
Newsgroups: comp.lang.ada
Subject: Re: right compilation unit for C as main?
Date: Tue, 18 Dec 2012 12:13:40 -0500
Organization: The World Public Access UNIX, Brookline, MA
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Date: 2012-12-18T12:13:40-05:00
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Brian Drummond <brian@shapes.demon.co.uk> writes:

> adainit() should not block! It should set the environment up for Ada and
> return to your C main program. Which will then call an ...ahhh, Ada
> procedure which WILL block because the tasks it creates cannot outlive
> it...

That's true only if it declares objects containing tasks.
If it allocates objects containing tasks via "new",
with the access type declared at library level, then the
tasks can outlive their creator.

Tasks can also be created during library-package elaboration,
which is called from adainit.

> So this Ada procedure must create your Ada tasks, and then execute a C 
> function from its procedure body - your actual C code lives here.
>
> But given this structure I don't see why you don't just use an Ada main.

Using an Ada main is usually easier, but using a C main is
also possible, and sometimes necessary for reasons outside
the Ada world.

- Bob