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From: Mats Weber <Mats.Weber@elca-matrix.ch>
Subject: Re: Tasks and C/C++ code.
Date: 1998/11/23
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Date: 1998-11-23T00:00:00+00:00
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Samuel Tardieu wrote:

> Mats> Why not ? If the C function is potentially blocking _and_
> Mats> non-reentrant (as is gethostbyname for example, which can take
> Mats> some time), then it's the only option.
> 
> 9.5.1 (8) During a protected action, it is a bounded error to invoke
>           an operation that is potentially blocking.
> 
> I think that the spirit of protected operations is to be really short.

OK, but the definition of "potentially blocking" does not include
imported subprograms (RM 9.5.1(8-18)). So I guess this is undefined. But
given the spirit of the definition, I agree that it would be better to
put the call in a task body instead of in a protected body, in order not
to be too close to the boundaries of the standard.

Anyway I have seen gethostbyname protected by a protected object (I
think it is in GLADE). So it does work.