From mboxrd@z Thu Jan  1 00:00:00 1970
To: 9fans@cse.psu.edu
Subject: Re: [9fans] 9P2000 and p9p
From: "Russ Cox" <rsc@swtch.com>
Date: Tue, 10 Apr 2007 18:50:34 -0400
In-Reply-To: <461C0C31.80000@tecmav.com>
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> It depends on the time between the two read.
> If they were within a few time slices the second
> one could return 0 without Tread to to the file server.
> The data coming in between the first and second
> read is (IMO) a false problem. All would go as the new data
> were arrived just after the second (true) read to the file server.

Your argument assumes no correlation between
the reads and the writes.

Maybe a test program does

	write
	read
	write
	read

Then you will fail the second read incorrectly.

Or maybe correlations between operations on different
machines will yield the same case.

It's fine to assert that playing fast and loose works for
the one case you have in mind.  It's not find to assert
that it works in general.

Russ