Re: [PATCH] Explicitly pass grub to install, install-grub*, install-grub, initialize-hard-disk and qemu-image.

[Danny Milosavljevic]

Hi Ludo,

> I prefer that setting PATH to point to the right GRUB, rather than
> having to carry the directory name of GRUB in 10 different places.

I much prefer not having a magical non-Guile variable influence which 
bootloader (!) is installed. Of all things this is the most sensitive part of 
the installation process - if the bootloader doesn't work you can't even 
emergency-boot - and it depends on PATH being set correctly at some remote 
place.

I think it's much better not to have spooky action at a distance.

> This is the approach taken in several places, such as (gnu system vm):
> we set PATH, and then we can happily call functions that in turn expect
> commands in $PATH.
> 
> Danny, what led you to this patch?  :-)

When I read the source I couldn't find which grub-install executable it invokes 
(and how that even works) and neither could anyone on the list for months (I 
asked). I think for maintenance it's much better not to use PATH but rather be 
explicit about which package it is. 

This is part of the u-boot and grub-efi effort. Of course it's optional to do 
it - grub, u-boot and grub-efi can work with PATH as well. But should they?

However if we aren't explicit about it then the next person will have to search 
around just like I did. 

Also it would keep being a Damocles' sword over our heads - if someone modifies 
PATH (in the Guix source code, by accident) it will just pick up a random grub 
(maybe Debian's if it's installed on a foreign distro - who knows?).