Mailing-List: contact cygwin-help AT cygwin DOT com; run by ezmlm
List-Subscribe: <mailto:cygwin-subscribe AT cygwin DOT com>
List-Archive: <http://sourceware.org/ml/cygwin/>
List-Post: <mailto:cygwin AT cygwin DOT com>
List-Help: <mailto:cygwin-help AT cygwin DOT com>, <http://sourceware.org/ml/#faqs>
Sender: cygwin-owner AT cygwin DOT com
Mail-Followup-To: cygwin AT cygwin DOT com
Delivered-To: mailing list cygwin AT cygwin DOT com
Date: Fri, 11 Feb 2005 15:25:42 +0100
From: Corinna Vinschen <corinna-cygwin AT cygwin DOT com>
To: cygwin AT cygwin DOT com
Subject: Re: more ctime bugs
Message-ID: <20050211142542.GE2597@cygbert.vinschen.de>
Reply-To: cygwin AT cygwin DOT com
Mail-Followup-To: cygwin AT cygwin DOT com
References: <020920052127 DOT 27398 DOT 420A803A0009BD7500006B0622007507440A050E040D0C079D0A AT comcast DOT net> <20050211093508 DOT GB27256 AT cygbert DOT vinschen DOT de> <420CBCE6 DOT 60603 AT byu DOT net>
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <420CBCE6.60603@byu.net>
User-Agent: Mutt/1.4.2i

On Feb 11 07:10, Eric Blake wrote:
> According to Corinna Vinschen on 2/11/2005 2:35 AM:
> > No problem with open and link, but I'm a bit reluctant to do this in
> > write.  Setting the file time on each WriteFile looks like a pretty
> > time consuming operation, so I'm a bit in doubt if every write operation
> > should be slowed down by this, POSIX compatibility or not.  Wouldn't
> > it help in most cases, if the close after write sets the ctime?
> 
> That idea is close to what I had in mind.  Note that POSIX wording in 4.7
> for updating file times,
> http://www.opengroup.org/onlinepubs/009695399/basedefs/xbd_chap04.html:
> 
> "An implementation may update fields that are marked for update
> immediately, or it may update such fields periodically. At an update point
> in time, any marked fields shall be set to the current time and the update
> marks shall be cleared. All fields that are marked for update shall be
> updated when the file ceases to be open by any process, or when a stat(),
> fstat(), or lstat() is performed on the file. Other times at which updates
> are done are unspecified. Marks for update, and updates themselves, are
> not done for files on read-only file systems; see Read-Only File System."
> 
> There is no minimum time specified for the periodic updates, [...]

Thanks to you and Dave, especially for quoting the above Open Group
chapter.  I'll update Cygwin to set ctime in close and link.  Link
is special since it doesn't involve using any explicit file descriptors,
so it's a bit unclear where to set the flags inside Cygwin to get that
right.  Using close() seems a good way to have ctime set for write()
as well as open(O_TRUNC).


Corinna

-- 
Corinna Vinschen                  Please, send mails regarding Cygwin to
Cygwin Project Co-Leader          mailto:cygwin AT cygwin DOT com
Red Hat, Inc.

--
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple
Problem reports:       http://cygwin.com/problems.html
Documentation:         http://cygwin.com/docs.html
FAQ:                   http://cygwin.com/faq/