X-Recipient: archive-cygwin AT delorie DOT com X-SWARE-Spam-Status: No, hits=-1.8 required=5.0 tests=AWL,BAYES_00,UNPARSEABLE_RELAY X-Spam-Check-By: sourceware.org X-Yahoo-SMTP: jenXL62swBAWhMTL3wnej93oaS0ClBQOAKs8jbEbx_o- Date: Mon, 7 Mar 2011 10:54:39 -0500 From: Christopher Faylor To: cygwin AT cygwin DOT com Subject: Re: tar --atime-preserve with an empty file triggers a warning Message-ID: <20110307155439.GB2538@ednor.casa.cgf.cx> Reply-To: cygwin AT cygwin DOT com Mail-Followup-To: cygwin AT cygwin DOT com References: <20110307152005 DOT 17292u50da242vth AT messagerie DOT si DOT c-s DOT fr> <4D74EC98 DOT 7090803 AT redhat DOT com> <20110307144349 DOT GE18640 AT calimero DOT vinschen DOT de> <4D74F4A8 DOT 2080505 AT redhat DOT com> <20110307154330 DOT GA12899 AT calimero DOT vinschen DOT de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20110307154330.GA12899@calimero.vinschen.de> User-Agent: Mutt/1.5.20 (2009-06-14) Mailing-List: contact cygwin-help AT cygwin DOT com; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: cygwin-owner AT cygwin DOT com Mail-Followup-To: cygwin AT cygwin DOT com Delivered-To: mailing list cygwin AT cygwin DOT com On Mon, Mar 07, 2011 at 04:43:30PM +0100, Corinna Vinschen wrote: >On Mar 7 08:07, Eric Blake wrote: >> [adding bug-tar] >> >> On 03/07/2011 07:43 AM, Corinna Vinschen wrote: >> > THis looks like a tar bug, per the strace. For some reason, if the >> > file is empty, tar calls futimens on file descriptor 0 (which is >> > connected to /dev/tty1 in my case), while it call futimens on >> > file descriptor 4 (connected to the file empty) if the file empty >> > is... well, not empty. >> >> This is indeed multiple bug reports for the price of 1 :) >> [...] >> Finally, cygwin is failing with EINVAL for futimens on a pty fd. >> However, I don't know if that's something that we can change, since >> cygwin doesn't really maintain a notion of changeable times on ptys at >> the moment. > >Please take this as granted for now. Ptys/ttys are implemented using >other Windows objects (events, pipes, etc) and none of them supports >setting a file time. I don't know if faking the ability to set the >filetime is really feasible. > >Maybe we should just return EPERM? Someday we really should implement something like devfs. cgf -- 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