About '-readconfig' [Was: Re: [PULL 27/29] vl: deprecate -writeconfig]

[Kashyap Chamarthy]

On Fri, Feb 26, 2021 at 09:05:24AM +0100, Paolo Bonzini wrote:
> The functionality of -writeconfig is limited and the code
> does not even try to detect cases where it prints incorrect
> syntax (for example if values have a quote in them, since
> qemu_config_parse does not support any kind of escaping)
> so remove it.
> 
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> ---
>  docs/system/deprecated.rst | 7 +++++++
>  qemu-options.hx            | 7 +------
>  softmmu/vl.c               | 1 +
>  3 files changed, 9 insertions(+), 6 deletions(-)

[...]

Hi,

Sorry, I'm coming very late[1] to the discussion.  Will there be a
replacement for '-readconfig'?

I agree with Gerd's comment[2] in the last year's thread (I missed to
notice at that time) about '-readconfig' being useful.  I'm familiar
with least one hosting provider who uses[3] '-readconfig'.  And I've
also used it for small snippets myself.  I understand, these simple
use-cases doesn't make it right to keep it. :-)

I'm not saying "don't deprecate '-readconfig'", but just noting its
usefulness, even in its current form.  So I'm just curious if there's
be a suggested replacement.  Even if it means: "use libvirt; or use your
own bespoke scripts".

[1] https://lists.nongnu.org/archive/html/qemu-devel/2020-05/msg03681.html
    "proposal: deprecate -readconfig/-writeconfig"
[2] https://lists.nongnu.org/archive/html/qemu-devel/2020-05/msg03681.html
[3] 
https://github.com/flyingcircusio/fc.qemu/blob/f789e57f605969a0/src/fc/qemu/agent.py#L1153

-- 
/kashyap