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From: robert_dewar@my-dejanews.com
Subject: Re: Stream venting (long)
Date: 1998/12/29
Message-ID: <769g3r$moq$1@nnrp1.dejanews.com>#1/1
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Date: 1998-12-29T00:00:00+00:00
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In article <768sng$6r9$1@nnrp1.dejanews.com>,
  dennison@telepath.com wrote:
>   1. Stream 'Writes and 'Reads are inherently task
>      unsafe. Possible solution 1a: You can of course try
>      to implement your stream in a
>      task safe manner. But as a stream implementor all
>      you will see is a series of
>      Write calls. A single 'Write from the client will
>      cause an indeterminate number of these. There's no
>      way to tell if a Write or Read call is the first
>      or last in a series. If you need to make the enitre
>      composite type's 'Write or 'Read atomic, you're SOL.

I find this complaint bizarre, I must not understand it
properly.

First, the idea of different tasks writing asynchronously
to a common stream seems an entirely bizarre program
organization.

Second, if you really *do* want such an organization, it
seems quite easy to program stream functions so that they
are properly atomic. I see no difficulty in doing this.
You just need a single lock, with a test that avoids
messing with it if it is already set.


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