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Subject: Re: [PATCH v2 08/92] fs: new helper: simple_rename_timestamp
From:   Jeff Layton <jlayton@kernel.org>
To:     Al Viro <viro@zeniv.linux.org.uk>
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Date:   Tue, 29 Aug 2023 20:48:48 -0400
In-Reply-To: <20230830001917.GC461907@ZenIV>
References: <20230705185812.579118-1-jlayton@kernel.org>
         <20230705185812.579118-3-jlayton@kernel.org>
         <20230830001917.GC461907@ZenIV>
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On Wed, 2023-08-30 at 01:19 +0100, Al Viro wrote:
> On Wed, Jul 05, 2023 at 02:58:11PM -0400, Jeff Layton wrote:
>=20
> > + * POSIX mandates that the old and new parent directories have their c=
time and
> > + * mtime updated, and that inodes of @old_dentry and @new_dentry (if a=
ny), have
> > + * their ctime updated.
>=20
> APPLICATION USAGE
> Some implementations mark for update the last file status change timestam=
p
> of renamed files and some do not. Applications which make use of the
> last file status change timestamp may behave differently with respect
> to renamed files unless they are designed to allow for either behavior.
>
> So for children POSIX permits rather than mandates.  Doesn't really matte=
r;
> Linux behaviour had been to touch ctime on children since way back, if
> not since the very beginning.

Mea culpa. You're quite correct. I'll plan to roll a small patch to
update the comment over this function.

Thanks!
--=20
Jeff Layton <jlayton@kernel.org>