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Message-ID: <1089925820.40f6f2bcf1d88@imp3-q.free.fr>
Date: Thu, 15 Jul 2004 23:10:20 +0200
From: Xavier Joubert <xavier DOT joubert AT free DOT fr>
To: cygwin AT cygwin DOT com
Subject: Re: [BUG] mprotect() on Windows NT 5+
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Hello Corinna,


Selon Corinna Vinschen <corinna-cygwin AT cygwin DOT com>:
> The cause is a limitation in newer Windows NT versions, which make sense.
> Well, sort of.  The protection modes PAGE_READWRITE and PAGE_WRITECOPY are
> mutually exlusive, which is enforced in calls to VirtualProtect since W2K.
>
> Since your example uses MAP_PRIVATE, which Cygwin maps to PAGE_WRITECOPY,
> trying to protect with MAP_WRITE, which internally maps to PAGE_READWRTE,
> fails on W2K and later.  I've checked in a fix, so that mprotect tests for
> the original protection mode of the first page in the area, and uses
> READWRITE or WRITECOPY, whichever matches the original protection.

Whow! That's amazing! I didn't expect to get a reply today. Even less a fix
commited to CVS. If all bugs last only 51 minutes in Cygwin, this software will
quickly become perfect!

Thanks _a lot_ Corinna !

I'll try Cygwin snapshot tomorrow and let you know how it goes with the real
stuff.


Xavier

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