Re: cp: --reflink=never

[Pádraig Brady]

On 17/06/18 17:50, Adam Borowski wrote:
> Hi!
> I see requests for cp --reflink=auto as the default happening a lot on the
> mailing list.  But, assuming there is a reason to ever want a heavy-weight
> copy[1], people might want to disable reflinking.  This applies regardless
> of what's the default: aliases or wrappers can be used for personal
> preferences.
> 
> Thus, if there's alias cp='cp --reflink=auto', there's no obvious way to
> skip it.
> 
> Here's a patch that implements --reflink=never, useful to override an
> earlier argument.
> 
> 
> Meow!
> 
> [1]. As a btrfs mailing list regular and occassional kernel/-progs
> contributor, I can't even think of any; nocow files are already handled.

We are probably going to change to trying reflink by default
in a new major release of coreutils (v9). Though it's a
significant behavior change and best done in a major version bump.

As for --reflink=never, that will be needed as you say,
and useful now in the edge case of people using --reflink=auto in aliases.
I will apply this for the upcoming 8.30 release.

The attached has added a bit more --help
and a test case.

cheers,
Pádraig

cp--reflink=never.patch
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