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From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Thu, 22 Jul 2010 08:14:42 -0700
Message-ID: <AANLkTikBCXK6uEwWq4f0LvpdoKCPs3jvyFa4Zw4e2J_7@mail.gmail.com>
Subject: Re: [PATCH 02/18] xstat: Add a pair of system calls to make extended
	file stats available [ver #6]
To: Volker.Lendecke@sernet.de
Cc: David Howells <dhowells@redhat.com>, Jan Engelhardt <jengelh@medozas.de>,
        linux-cifs@vger.kernel.org, linux-nfs@vger.kernel.org,
        samba-technical@lists.samba.org, linux-kernel@vger.kernel.org,
        viro@zeniv.linux.org.uk, linux-fsdevel@vger.kernel.org,
        linux-ext4@vger.kernel.org
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Sender: linux-nfs-owner@vger.kernel.org
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On Thu, Jul 22, 2010 at 5:17 AM, Volker Lendecke
<Volker.Lendecke@sernet.de> wrote:
> On Thu, Jul 22, 2010 at 01:14:47PM +0100, David Howells wrote:
>> Jan Engelhardt <jengelh@medozas.de> wrote:
>>
>> > Linux already has a creation time field, it's called otime (there is no "b"
>> > in "creation"), and you will find scattered fragments of that all over the
>> > kernel (foremost, fs/jfs/, now btrfs, and I also notice sysvipc having
>> > something with that name).
>>
>> It is? ?It's called crtime in Ext4. ?st_btime, however, would be compatible
>> with BSD's stat, and Samba would just use it by way of autoconf magic if it
>> appeared.
>
> Samba has the following check:
>
> # recent FreeBSD, NetBSD have creation timestamps called birthtime:
> AC_CHECK_MEMBERS([struct stat.st_birthtimespec.tv_nsec])
> AC_CHECK_MEMBERS([struct stat.st_birthtime], AC_CHECK_MEMBERS([struct stat.st_birthtimensec]))
>
> and the supporting code around that. "birth" might also be
> where the "b" comes from :-)

Oh wow. And all of this just convinces me that we should _not_ do any
of this, since clearly it's all totally useless and people can't even
agree on a name.

Let's wait five years and see if there is actually any consensus on it
being needed and used at all, rather than rush into something just
because "we can".

                       Linus