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From: Jamie Landeg-Jones <jamie@catflap.org>
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Date: Tue, 03 Sep 2024 01:05:59 +0100
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Subject: Re: mount -u removes "noatime"
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Konstantin Belousov <kostikbel@gmail.com> wrote:

> This is how mount update works.  How otherwise would you remove noatime
> from the options?  It seems to be true for other 'flag' options as well.
>
> Really nonoatime should work with nmount, but it probably does not.

mount -u -o atime works.

Thanks for the clarification. It seems counterintuitive to me though.

As it stands, how do we preserve atime status without scripting around it? Maybe at least the manual page should make this clearer?

> Indeed, we ensure immutability of snapshots by directly checking the fact
> that the file accessed for write cannot be snapshot.  The paragraph perhaps
> should be reformulated to state that instead.

Yeah. That would be clearer, because adding/removing schg manually makes no difference, due tobthe reasons you cite.

i'll knock up a PR for the manpages if that helps, 

Thanks, Jamie.