Re: guix system init co-existing with other distros

[Jan Nieuwenhuizen]

Ludovic Courtès writes:

> Jan Nieuwenhuizen <address@hidden> skribis:
>>    (grub-configuration
>>     (device "/dev/sda")
>>      (list (menu-entry
>>             (label "debian")
>>             (linux "(hd0,msdos3)/boot/latest")

> Did you run “guix system init config.scm /”?

Fear not.  Debian lives on /dev/sda3, guix on /sda1.  From Debian
I dit guix system init config.scm /guix

> Good question!  I’m not sure I fully understand your hack but I’d like
> to read more about it.  :-)

So what I need is for Guix's Grub to create an extra menu entry
for Debian, with this text

    menuentry 'Debian GNU/Linux' {
        linux   /boot/vmlinuz-3.16.0-4-amd64 root=/dev/sda3 ro
        initrd  /boot/initrd.img-3.16.0-4-amd64
    }

When you specify extra an extra menu-entry

       (list (menu-entry
             (label "debian")
             (linux "<file-name>")
             (initrd "<file-name>))

then grub.scm:(grub-configuration-file) appends "/" "bzImage" to the
kernel's file-name

    (define linux-image-name
        (if (string-prefix? "mips" system)
            "vmlinuz"
            "bzImage"))

So, I setup some symlinks on the Debian side so that I can provide Guix's
Grub wih a kernel file name that can have "/bzImage" appended.

    23:42:13 address@hidden:~/src/guix
    $ ls -l /debian/boot/latest/
    totaal 0
    lrwxrwxrwx 1 root root 28  6 feb 21:17 bzImage -> 
/boot/vmlinuz-3.16.0-4-amd64
    lrwxrwxrwx 1 root root 31  6 feb 21:17 initrd -> 
/boot/initrd.img-3.16.0-4-amd64

Possibly we'd want to add another keyword

         (linux-image "(hd0,msdos3)/boot/vmlinuz-3.16.0-4-amd64")

that gets used literally?

Greetings, Jan

-- 
Jan Nieuwenhuizen <address@hidden> | GNU LilyPond http://lilypond.org
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