Re: Activating a configuration file within a submenu or a menuentry

[Arbiel Perlacremaz]

Oh, yes, the example menuentry you gave me works perfectly, and I thank 
you for that. I've been able to have grub executing each selected 
grub.cfg file.

The trouble arises from the fact that these grub.cfg files each use 
their specific ${prefix} variable. And these variables are used in 
particular to "source" the ${prefix}/custom.cfg file if it exists.

So, to get the menu as if the PC had been booted by the grub's instance 
which refers to one of the other_cfg files, I have to set prefix = 
${2}/boot/grub, the directory which I have Grub read the grub.cfg file, 
and export it to have it available in that subsequent configfiled 
grub.cfg file.

Obviously, difficulties may arise, as you have stated, when all Grub 
instances of a given configuration are not at the same level, which is 
presently not the case in my configuration.

However, this shows a design pitfall : Grub uses a single variable for 
two different purposes : accessing its own modules and accessing user 
defined files. It should use two variables.

However, the use of two variables may not be enough to clear the issue. 
Wouldn't we face inconsistencies if the grub version current when a user 
runs grub-mkconfig is not the same as the one which was current when he 
previously ran the grub-install procedure ?


What do you think ?

Le 09/04/2012 20:40, Jordan Uggla a écrit :
> On Mon, Apr 9, 2012 at 6:20 AM, Arbiel Perlacremaz
> <address@hidden>  wrote:
> > Thank you Jordan
> >
> > It works perfectly after I have added
> >
> > set prefix=${2}/boot/grub
> > export prefix
>
> $prefix is where grub looks for its modules, you should never be
> changing it yourself in scripts because if you change $prefix to point
> to an older (or newer) grub's /boot/grub/ directory the modules in
> that directory will likely be incompatible. The example menu entry I
> gave should have worked, did it not work?