Re: grub shell: unkown commands alwasy exit with zero code

[Vladimir 'phcoder' Serbinenko]

On Tue, Jan 16, 2024 at 11:34 AM Michael Chang via Grub-devel
<grub-devel@gnu.org> wrote:
>
> On Fri, Jan 12, 2024 at 05:58:02PM +0100, Itxaka serrano wrote:
> > Hey all,
> >
> > I opened a bug because this behaviour doesnt seem correct to me:
> >
> > https://savannah.gnu.org/bugs/?65154
> >
> >
> > Example:
> >
> > grub> hello
> > error: ../../grub-core/script/function.c:119:can't find command `hello'.
> > grub> echo $?
> > 0
> >
> >
> > Kind of weird because on the code it seems like its returning a
> > GRUB_ERR_UNKNOWN_COMMAND which should not be zero. I had a quick look and
> > maybe its becuase on line 1018 of grub-core/script/execute.c we print the
> > error but always return 0
> > https://git.savannah.gnu.org/cgit/grub.git/tree/grub-core/script/execute.c#n1018
> >
> > Is this expected behaviour or is it a mistake and we should not only print
> > the error but return the actual error?
>
> The behavior is expected:
>
> https://git.savannah.gnu.org/cgit/grub.git/commit/?id=bc028f2f86.
>
$? is set before clearing error so it should be set to unknown
command. So looks like there is more to it.

> Given the limited context, it remains unclear if the rationale behind
> this change can be easily retraced today.
>
> My take is that this modification may have been implemented to support
> the continued functionality of older `grub.cfg` files, even after
> certain commands have been removed. This ensures compatibility with the
> latest version of GRUB. Alternatively, it seems reasonable to halt
> execution when encountering a missing command, considering the potential
> consequence of such situations.
We can have an equivalent of "shopt -e" for those cases. Current
default matches default sh use.