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Message-ID:	<41FD7A5F.2040407@x-ray.at>
Date:	Mon, 31 Jan 2005 01:22:55 +0100
From:	Reini Urban <rurban AT x-ray DOT at>
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To:	cygwin AT cygwin DOT com
Subject:	Re: Why does cygwin1.dll use NtCreateFile() instead of CreateFile()
References:	<20050130233747 DOT 5199 DOT qmail AT web80101 DOT mail DOT yahoo DOT com>
In-Reply-To:	<20050130233747.5199.qmail@web80101.mail.yahoo.com>
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Dan Ch schrieb:
> Thank you for providing some information.  But I do not understand
> what types of objects require read permission in order to successfully
> open with SYNCHRONIZE access.  On Windows XP Professional SP2, using
> CreateFile(...,GENERIC_WRITE | SYNCHRONIZE, ...) to open an ordinary
> file on a local drive that has write-only permissions does not seem
> to be a problem.  I am primarily interested in the "buggy behavior"
> that a user would experience if CreateFile() was used instead
> of NtCreateFile().

Special filenames in subdirs like con,prn,aux,nul,lpt1 et al do not work 
with CreateFile(), but do work as plain files with NtCreateFile().

See attached test.
-- 
Reini Urban
http://xarch.tu-graz.ac.at/home/rurban/

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