bug#44353: [PATCH version-1.2.0 v2] guix: system: Add a new '--non-volatile' option for disk-image.

[Ludovic Courtès]

Hi Maxim,

Maxim Cournoyer <maxim.cournoyer@gmail.com> skribis:

> * guix/scripts/system.scm (%options)[volatile-root?]: New boolean option.
> (%default-options): Set its default value to #f.
> (show-help): Add help doc.
> * guix/scripts/system.scm (perform-action): Propagate option...
> (system-derivation-for-action): ...here.  Use it to set the volatile-root?
> field of the image object passed to SYSTEM-IMAGE.
> * doc/guix.texi (Invoking guix system): Document it.

Due notably to the “string freeze”, I think we shouldn’t apply it to
‘version-1.2.0’.

Some comments:

> +@code{disk-image}.  By default, the root file system of a disk image is
> +mounted volatile; the @option{--non-volatile} option can be used to make

That’s not generally the case, though in (gnu system image), only two
image types have it set to false.

Before the new image API though, ‘disk-image’ did not produce a volatile
root, IIRC.  I’m tempted to think that we should set (volatile-root?
#f) on image types where it makes sense, which is maybe all of them
except ISO.  (Then we need to make sure ‘guix system vm’ still gets a
volatile root.)

WDYT, Mathieu?

So apart from the sentence above, the patch LGTM for ‘master’!

Thanks,
Ludo’.