From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 5757 invoked by alias); 25 Jul 2011 14:01:28 -0000 Received: (qmail 5672 invoked by uid 22791); 25 Jul 2011 14:01:01 -0000 X-Spam-Check-By: sourceware.org Received: from aquarius.hirmke.de (HELO calimero.vinschen.de) (217.91.18.234) by sourceware.org (qpsmtpd/0.83/v0.83-20-g38e4449) with ESMTP; Mon, 25 Jul 2011 14:00:41 +0000 Received: by calimero.vinschen.de (Postfix, from userid 500) id 5B2352CB274; Mon, 25 Jul 2011 16:00:38 +0200 (CEST) Date: Mon, 25 Jul 2011 14:01:00 -0000 From: Corinna Vinschen To: cygwin@cygwin.com Subject: Re: Device names in /proc/mounts Message-ID: <20110725140038.GA22821@calimero.vinschen.de> Reply-To: cygwin@cygwin.com Mail-Followup-To: cygwin@cygwin.com References: <9B10FEAACF062F48A095880A451FF0590380117C0C@DEMCHP99E84MSX.ww902.siemens.net> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <9B10FEAACF062F48A095880A451FF0590380117C0C@DEMCHP99E84MSX.ww902.siemens.net> User-Agent: Mutt/1.5.21 (2010-09-15) Mailing-List: contact cygwin-help@cygwin.com; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: cygwin-owner@cygwin.com Mail-Followup-To: cygwin@cygwin.com X-SW-Source: 2011-07/txt/msg00333.txt.bz2 On Jul 25 14:29, Schwarz, Konrad wrote: > There seems no way of mapping device names (resp. Win32 Device Namespace names) to mount points -- Cygwin mount pounts are not mapping disk devices to POSIX pathnames, but Win32 pathnames to POSIX pathnames. > the Cygwin User's Guide suggests using comparing the output of /proc/partitions with the output > of df(1) to match up the two. > > It then pointedly uses the registry > entry '\HKEY_LOCAL_MACHINE\SYSTEM\MountedDevices' -- which encodes the mapping > from NT device names to DOS device names -- as an example for regtool(1) > (see http://www.cygwin.com/cygwin-ug-net/using-specialnames.html#pathnames-proc-registry). > It does not explain how to decode the information there -- but neither does MSDN. Huh? This is just an example for the virtual /proc/registry access. It has nothing to do with device mapping. See http://www.cygwin.com/cygwin-ug-net/using-specialnames.html#pathnames-posixdevices instead, which shows how POSIX devices are mapped to native NT devices. > However, blk_id(8) describes volumes in terms of (Cygwin) device names (/dev/sda2), > so an easier to use mapping would be nice to have. It would also increase compatibility > between Cygwin and Linux. > > Some poking around MSDN reveals the function QueryDosDevice. This function's purpose would > seem to be to map DOS names to Win32 device names. Would it make sense to use > this to populate the first column of /proc/mounts (after mapping Win32 device > names \\.\ to Cygwin device names /dev/sdxy)? No. As I wrote above, Cygwin mount pounts are not mapping devices but Win32 pathnames to POSIX pathnames. Devices just don't make sense in this context. The mapping from NT devices to POSIX devices is used for direct device access only. Corinna -- Corinna Vinschen Please, send mails regarding Cygwin to Cygwin Project Co-Leader cygwin AT cygwin DOT com Red Hat -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple