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Date: Wed, 27 Jun 2001 02:31:28 -0400
From: Christopher Faylor <cgf AT redhat DOT com>
To: cygwin AT cygwin DOT com
Subject: Re: pthreads works, sorta
Message-ID: <20010627023128.R19058@redhat.com>
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References: <EA18B9FA0FE4194AA2B4CDB91F73C0EF7A0C AT itdomain002 DOT itdomain DOT net DOT au> <030b01c0fed5$afbfddd0$c9823bd5 AT dima>
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In-Reply-To: <030b01c0fed5$afbfddd0$c9823bd5@dima>; from dmitry@baikal.ru on Wed, Jun 27, 2001 at 02:51:13PM +0800

On Wed, Jun 27, 2001 at 02:51:13PM +0800, Dmitry Timoshkov wrote:
>"Robert Collins" <robert DOT collins AT itdomain DOT com DOT au> wrote:
>
>[skipped]
>
>> What does all this mean? We need to catch invalid memroy access, and
>> ValidQuery was supplied by Chris as a tool to do that.
>
>In a multithreaded environment VirtualQuery, IsBad* and similar approaches
>are wrong. It can't be guaranteed that after a successful test that memory
>will be still accessable.

They are not necessarily wrong if they are controlled by appropriate mutexes.
The file handling code should be protected this way.   I don't know about
the thread code, though.

cgf

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