Re: [PATCH v3 4/4] qemu-img: Deprecate use of -b without -F

[Kashyap Chamarthy <kchamart@redhat.com>]

On Tue, Mar 10, 2020 at 07:15:29AM -0500, Eric Blake wrote:
> On 3/10/20 4:47 AM, Kashyap Chamarthy wrote:
 
[...]

> > <digression>
> > 
> > Ah, didn't realize the inconsistency of 'convert' lacking the '-F'
> > shorthand ... which reminds me, there are at least _three_ ways that I
> > know of, to specify backing file format with 'create':
> > 
> >      $ qemu-img create -f qcow2 -o 'backing_file=./base.raw,backing_fmt=raw' ./overlay1.qcow2
> >      $ qemu-img create -f qcow2 -b ./base.raw -o backing_fmt=raw overlay1.qcow2
> >      $ qemu-img create -f qcow2 -b ./base.raw -F raw ./overlay1.qcow2
> > 
> > I'm wondering about the consistency of having all the above three
> > supported for other operations too.  Now I at least know 'convert' lacks
> > the "-F".
> 
> The -o forms (backing_file= and backing_fmt=) always work.  Various commands
> then have additional shorthand: -b/-F for create, -B for convert.  You're
> right that we aren't very consistent, but I'm reluctant to change the
> inconsistencies in this patch 

Oh, I wasn't implying to tackle the inconsistency as part of this
patch, or series.  Hence the 'digression' :-)  Was just wondering out
loud.

> (at one point in the past, we tried to get rid
> of the shorthand and force all users to go through -o, but that broke too
> many clients that were depending on the undocumented shorthand, so we
> documented the existing shorthand instead).

Fair enough; let's not touch these things for now.

-- 
/kashyap