From: Thomas Meyer <thomas@m3y3r.de>
To: Rob Landley <rob@landley.net>
Cc: "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: Copy on write hard links?
Date: Wed, 25 Sep 2013 16:28:53 +0200 [thread overview]
Message-ID: <1380119333.7453.4.camel@localhost.localdomain> (raw)
In-Reply-To: <1380117572.1974.81@driftwood>
Am Mittwoch, den 25.09.2013, 08:59 -0500 schrieb Rob Landley:
> On 09/24/2013 01:36:56 PM, Thomas Meyer wrote:
> > Hi,
> >
> > Is there such a thing?
>
> In the kernel's vfs layer?
Yes, that would be a nice feature!
> No, although some filesystems (ala btrfs) do
> things like that with snapshots.
>
> In userspace? Breaking hardlinks when updating a file is fairly normal,
> that's why they distinguish between "truncate and rewrite" (preserve
> hardlinks) and "write new file and rename over old file" (break
> hardlinks, avoiding the more obvious race conditions).
so every user space application needs to implement that for itself?
I wonder how hard it would be to implement this on vfs layer? linkat()
with a new flag as api or something like that.
>
> Rob
next prev parent reply other threads:[~2013-09-25 14:29 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-09-24 18:36 Copy on write hard links? Thomas Meyer
2013-09-25 1:40 ` Adam Borowski
2013-09-25 13:59 ` Rob Landley
2013-09-25 14:28 ` Thomas Meyer [this message]
2013-09-25 14:37 ` richard -rw- weinberger
2013-09-29 5:22 ` Pádraig Brady
2013-09-29 7:14 ` Richard Weinberger
2013-09-29 17:19 ` Pádraig Brady
2013-12-13 22:58 ` Jörn Engel
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