Re: GtkAda with several task (or distributed solution?)?

[Ted Dennison<dennison@telepath.com>]

In article <cevG6.3620$gX3.225371@news3.oke.nextra.no>, Frank says...
>> Any multi-word data they share may need to be protected from "tearing"
>I'm not sure I understand what you mean here;
>do you mean that if I try to pass a GUI object (the data structure of it)
>between partitions it can be destroyed when (can imagine that)?

No. "Data tearing" is the term I've heard simulation folk use for what CS people
like to call "race conditions" on data. What I'm saying is that if you have one
task updating multi-word data (eg: the xyz acceleration vector of an object),
and another accessing it from over the network, its quite possible for the
reader to see a snapshot of the object with time 1's values for z and time 2's
values for x and y. That would essentially make the overall value complete
garbage. You have to place some kind of read protection (locking, protected
object, etc.) around multi-word objects to prevent this. In many cases (I don't
know about annex E), this can also happen with 64-bit floats.

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