Re: Set a bootdrive environment variable.

[Andrei Borzenkov <arvidjaar@gmail.com>]

В Tue, 26 May 2015 12:46:07 -0400
Mathieu Trudel-Lapierre <mathieu.tl@gmail.com> пишет:

> I've been playing with fixing Ubuntu bug 1097570; trying to debug a script we
> use for the EFI images which detects where to boot from based on the location
> of a .disk/info file.
> 
> Turns out this mostly works, except for the fact that grub appears to always
> list devices in a specific order, which interferes with the detection if more
> than one device contains that file.
> 
> I think I can make this work appropriately provided we:
>   - Use hints for search --file;
>   - Have some value to pass to --hint= designating the boot drive.
> 

If you always want to use the same device GRUB was booted from why do
you need to search for anything at all?

> Included is a patch that adds a "bootdrive" variable alongside cmdpath; which
> contains just the drive designation for the boot device, to be used as such:
> 
> search --set=root --hint=$bootdrive --file .disk/info
> 
> I'd much appreciate review on that patch :)
> 

You can extract it from $cmdpath using regexp already. In retrospect
having separate variables for device and path would be more flexible;
but $drive is not appropriate name as it can refer to network as well.
Something like $grub_bootdev and $grub_bootpath.