Re: GRUB patch for 'lilo -R' functionality

[Robert Millan]

[ Chaging CC from bug-hurd to bug-grub. Sorry, my mistake. ]

On Tue, Nov 11, 2003 at 08:54:39PM +0000, Keir Fraser wrote:
> > > I only changed the behaviour of savedefault when executed within the
> > > GRUB-util shell (ie. not GRUB menu mode). I can't think of a scenario
> > > where the '--once' semantics would be useful to access from the GRUB
> > > menu, so I'm reluctant to 'fix' this behaviour.
> > 
> > I think there's a missunderstanding here. savedefault itself is only
> > meaningful in the context of the menu. The problem I noticed is that while
> > "savedefault --default=X" affects the GRUB menu, the "--once" argument has
> > no effect. I.e: once you run savedefault it won't be restored to 0 after the
> > next GRUB run.
> 
> Yes, clearly there is a misunderstanding!
> 
> Without my patch it is indeed the case that savedefault has no meaning
> outside the GRUB menu script. It's only use in that context is to
> cause GRUB to default to "what you last picked".

I know that. But I was referring to your modified "savedefault --default=X"
command.

> My patch makes savedefault useful in the context of the GRUB
> shell. Specifying --once to savedefault in the GRUB shell will cause
> teh following behavior:
>  1. The specified default will be used on next boot.

Yes (with your patch, that is)

>  2. Any specified timeout will be ignored on next boot (i.e. the menu
>     won't even be displayed).

That happens with later revisions of your patch, where you added that
feature. However, as previously discussed, it's preferrable not to do this.

>  3. After next boot, the above behaviour will be disabled until next
>     use of savedefault --once from GRUB shell.

But that doesn't work with your patch. Presumably, _SAVED_ENTRYNO is not
reset to 0, either because _ONCEONLY_ENTRY is not set in the GRUB shell, or
because it is not honored by GRUB when booting.

Could you have a look at that?

> Maybe I should have created a new command name instead of confusingly
> overloading savedefault in this way. :-(  In fact, I think adding a
> new command, useable only from GRUB shell, would be quite easy.

Uhm.. no. IIRC we discussed this previously and Okuji said it's preferrable
to make it into the same command.

-- 
Robert Millan

"[..] but the delight and pride of Aule is in the deed of making, and in the
thing made, and neither in possession nor in his own mastery; wherefore he
gives and hoards not, and is free from care, passing ever on to some new work."

 -- J.R.R.T, Ainulindale (Silmarillion)