Re: GuixSD bootable ISO-9669 image

[Danny Milosavljevic]

> (define (iso9660-superblock-uuid sblock)
>   "Return the Volume ID of a iso9660 superblock SBLOCK as a 4-byte 
> bytevector."
>   ;; Note: The field is the volume creation time.
>   ;; FIXME Use only certain parts (See grub).

Grub drops the timezone.  So do blkid and /dev/disk/by-uuid .

>   ;; FIXME treat "all 0" as invalid.

The creation timestamp is actually optional in ISO-9660 (in case it's not given 
it's supposed to be 0) so it could be that the uuids on the system are not all 
that unique.  I think this case should be caught in the generic uuid matcher 
too.