From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cuda.sgi.com (cuda1.sgi.com [192.48.157.11]) by oss.sgi.com (8.14.3/8.14.3/SuSE Linux 0.8) with ESMTP id nBNJMsnW259165 for ; Wed, 23 Dec 2009 13:22:55 -0600 Received: from mail.parknet.co.jp (localhost [127.0.0.1]) by cuda.sgi.com (Spam Firewall) with ESMTP id D8A79134ECDA for ; Wed, 23 Dec 2009 11:23:36 -0800 (PST) Received: from mail.parknet.co.jp (mail.parknet.co.jp [210.171.160.6]) by cuda.sgi.com with ESMTP id isymQeHirBgVerji for ; Wed, 23 Dec 2009 11:23:36 -0800 (PST) From: OGAWA Hirofumi Subject: Re: [fuse-devel] utimensat fails to update ctime References: <4B2B156D.9040604@byu.net> <87aaxclr4q.fsf@devron.myhome.or.jp> <4B2F7421.10005@byu.net> <4B2F7A95.3010708@byu.net> <87hbrkjrk8.fsf@devron.myhome.or.jp> <4B304D04.6040501@byu.net> <87d427jscr.fsf@devron.myhome.or.jp> <4B3097C4.3060803@wanadoo.fr> <874onjjnln.fsf@devron.myhome.or.jp> <4B30B67A.7080703@wanadoo.fr> <87ljgvi1an.fsf@devron.myhome.or.jp> <4B30F0C9.2020702@wanadoo.fr> <87my1aevro.fsf@devron.myhome.or.jp> <4B3212ED.4090208@byu.net> Date: Thu, 24 Dec 2009 04:23:28 +0900 In-Reply-To: <4B3212ED.4090208@byu.net> (Eric Blake's message of "Wed, 23 Dec 2009 05:54:05 -0700") Message-ID: <87vdfxmr4f.fsf@devron.myhome.or.jp> MIME-Version: 1.0 List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: xfs-bounces@oss.sgi.com Errors-To: xfs-bounces@oss.sgi.com To: Eric Blake Cc: Miklos Szeredi , fuse-devel@lists.sourceforge.net, bug-coreutils , Linux Kernel Mailing List , xfs@oss.sgi.com, ctrn3e8 , Jean-Pierre =?iso-8859-1?Q?Andr=E9?= , Christoph Hellwig Eric Blake writes: > By the way, is there any reliable way, other than uname() and checking for > a minimum kernel version, to tell if all file systems will properly > support UTIME_OMIT? Um... sorry, I don't know. And it might be hard to detect efficiently if the workaround is enough efficient like one fstat() syscall (Pass fd to kernel. I.e. just read from cached inode). > For coreutils 8.3, we will be inserting a workaround where instead of > using UTIME_OMIT, we call fstatat() in advance of utimensat() and pass > the original timestamp down. But it would be nice to avoid the > penalty of the extra stat if there were a reliable way to ensure that, > regardless of file system, the use of UTIME_OMIT will be honored. > After all, coreutils wants touch(1) to work regardless of how old the > user's kernel and file system drivers are. Or it would depend on coreutils policy though, personally I think it's ok that it ignores the bug as known fs bug, otherwise coreutils would need to collect workarounds on several filesystems of several OSes. Thanks. -- OGAWA Hirofumi _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs