From: Jan Engelhardt Subject: Re: [PATCH 02/18] xstat: Add a pair of system calls to make extended file stats available [ver #6] Date: Thu, 22 Jul 2010 12:52:36 +0200 (CEST) Message-ID: References: <20100715021709.5544.64506.stgit@warthog.procyon.org.uk> <20100715021712.5544.44845.stgit@warthog.procyon.org.uk> <20100718084824.GA27794@infradead.org> Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Cc: David Howells , viro@ZenIV.linux.org.uk, linux-fsdevel@vger.kernel.org, linux-nfs@vger.kernel.org, linux-cifs@vger.kernel.org, linux-kernel@vger.kernel.org, samba-technical@lists.samba.org, linux-ext4@vger.kernel.org, drepper@redhat.com, torvalds@linux-foundation.org To: Christoph Hellwig Return-path: Received: from borg.medozas.de ([188.40.89.202]:51809 "EHLO borg.medozas.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755177Ab0GVKwh (ORCPT ); Thu, 22 Jul 2010 06:52:37 -0400 In-Reply-To: <20100718084824.GA27794@infradead.org> Sender: linux-ext4-owner@vger.kernel.org List-ID: On Sunday 2010-07-18 10:48, Christoph Hellwig wrote: >Adding Uli to the Cc list to make sure this system call is useful >for glibc / can be exported by it. Otherwise it's rather pointless >to add it. > >> (6) BSD stat compatibility: Including more fields from the BSD stat such as >> creation time (st_btime) and inode generation number (st_gen) [Jeremy >> Allison, Bernd Schubert] > >How is this different from (1) and (4)? (4), the inode generation number, need not be related to time. >> (8) Allow the filesystem to indicate what it can/cannot provide: A filesystem >> can now say it doesn't support a standard stat feature if that isn't >> available. > >What for? Given xstat.otime=0, how would you determine whether the file is really tagged with a date of 1970, or whether it's just the fs which didnot store this kind of information.