From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 50658 invoked by alias); 21 Oct 2015 11:07:38 -0000 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 Received: (qmail 50646 invoked by uid 89); 21 Oct 2015 11:07:37 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-5.4 required=5.0 tests=AWL,BAYES_00,KAM_LAZY_DOMAIN_SECURITY autolearn=no version=3.3.2 X-HELO: calimero.vinschen.de Received: from aquarius.hirmke.de (HELO calimero.vinschen.de) (217.91.18.234) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Wed, 21 Oct 2015 11:07:36 +0000 Received: by calimero.vinschen.de (Postfix, from userid 500) id 13F8CA807CB; Wed, 21 Oct 2015 13:07:34 +0200 (CEST) Date: Wed, 21 Oct 2015 11:07:00 -0000 From: Corinna Vinschen To: cygwin@cygwin.com Subject: Re: fstat st_size on open files on Parallels filesystem is wrong Message-ID: <20151021110734.GO5319@calimero.vinschen.de> Reply-To: cygwin@cygwin.com Mail-Followup-To: cygwin@cygwin.com References: <21333.25325.11106.958642@compute01.cs.columbia.edu> <227151856.20140421223417@yandex.ru> <21333.26515.393838.380071@compute01.cs.columbia.edu> <20140422081628.GC2339@calimero.vinschen.de> <21334.55207.784319.488271@compute01.cs.columbia.edu> <20140423084056.GJ2339@calimero.vinschen.de> <21335.61113.963950.516021@compute01.cs.columbia.edu> <20140423172413.GQ2339@calimero.vinschen.de> <22038.38637.802707.846218@compute03.cs.columbia.edu> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="rFUhhEVnhEf/dYhU" Content-Disposition: inline In-Reply-To: <22038.38637.802707.846218@compute03.cs.columbia.edu> User-Agent: Mutt/1.5.23 (2014-03-12) X-SW-Source: 2015-10/txt/msg00336.txt.bz2 --rFUhhEVnhEf/dYhU Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Content-length: 2578 On Oct 8 12:16, Jonathan Lennox wrote: > Hi, following up on this issue from last year. The message I'm replying = to > is at . >=20 > The problem is weird behavior in Parallels Desktop-hosted Windows VMs, wh= en > accessing the host's native Mac OS X filesystem. See the thread for the > details. >=20 > On Wednesday, April 23 2014, "Corinna Vinschen" wrote to "cygwin@cygwin.c= om" saying: >=20 > > > At this point this is looking pretty clearly like a Parallels Tools b= ug. > > > I'll report it to them. > >=20 > > Yes, that sounds good. Given that, I'm wondering if we should try to > > workaround this problem at all or rather wait to see if the vendor will > > fix the issue. >=20 > No such luck, despite two major version revisions of Parallels Desktop (I= 'm > now on version 11.0.2) and moving to Windows 10 as the guest OS -- the bug > perists, unchanged. So it looks like Cygwin will need to add a workaround > for this filesystem to fix the problem. Ok, we could do that. Can you compile and run the testcase from https://cygwin.com/ml/cygwin/2014-04/msg00523.html again? Does it still show 0 vs. 12 bytes? Dumb extra test: Does the output change if you reorder the calls, requesting FileStandardInformation first, FileNetworkOpenInformation second? > The output of /usr/lib/csih/getVolInfo seems to be unchanged from the out= put > I reported last year. >=20 > > Thanks. This looks pretty much like a filesystem pretending to be > > FAT-like. There may be another problem lurking, which is, are the inode > > numbers (called "FileId" or "IndexNumber" in Windows) persistant? With > > FAT this is not the case, and given the above, it might be a problem... > >=20 > > ...or not. I just realize that Cygwin doesn't even try to use the > > FileId as inode number on filesystems with FILE_PERSISTENT_ACLS=3D=3DFA= LSE > > so, never mind. > >=20 > > OTOH, does it support hardlinks? If so, two hardlinks to the > > same file would have different inode numbers on Cygwin. >=20 > How would I figure these points out? Just create a hardlink on that drive using native means: $ touch foo $ cmd /c mklink /h bar foo Error at this point? No hardlinks. Otherwise: $ ls -li foo bar Are the inode numbers identical? Congrats, hardlinks work. But given the general FAT-iness of the getVolInfo output, I guess it doesn't maintain hardlinks. Corinna --=20 Corinna Vinschen Please, send mails regarding Cygwin to Cygwin Maintainer cygwin AT cygwin DOT com Red Hat --rFUhhEVnhEf/dYhU Content-Type: application/pgp-signature Content-length: 819 -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQIcBAEBCAAGBQJWJ3H1AAoJEPU2Bp2uRE+gUaIP/3GSfFlFw2N7AFjuFS6vtIFZ bZXl7na4TE8gsQ5apNjq3TWvr10kUdgjEd/4W9RPq5gwQ9m+8YZ5MmflR1HXCE0w KXXjO5B4Go3tPYXcXHOyU2vXGCnLtK0FmvDUhZBPuvuMHPZK7sYQZZ9wIizhTgU7 Q1DnxyKk88Oj52DLcGSaAho0/0+nziexxNyyl2qO3qh+ja1iFunKy2RPAVNDDeHo lv3WOzxPK2nmjNehy5mTmkFrc+/B9k85Et9I+vOZgKSb4Omjy82EJA2El8PO/Ibk Z99t8oIK2CC8UypeAvEhnn14FHXPJ1DlbUWHKDiZ5H0imPJrG+10LaK2eSIbwhfS 8EnEedZfsu8vEte6KUiohw7IdS/AGijurKbiWhjOUbp3EgHlEa6YIdML/oa6UcR8 H7TiWM7lgP++GBQTF6Vx483J+2f8oo8Yt/gMphGdTmgoJQESkVfvDRNNb7PMz35C DuWiAJ+vbSUhLTLLz/JvIH/vAvdMb+RG5+dMyJDVGvoW9SSCvYReMRsePelI4ANU AkRuzBt+2jBwWcOBbzVFxCir6Gn2Zr/FWr67qj5MuhcZF+X3YxdNovkrFINPCuA2 Fs9nNiapAo5dj4q589bZ5q5rJeHh5BC4s418Lx/iwB9UlCtVisKmWJWzBcx2iUDW xLI5j3Su0bPLwoIwKrEf =+hx+ -----END PGP SIGNATURE----- --rFUhhEVnhEf/dYhU--