Re: grub-mkrescue problems in argp_parse

["Thomas Schmitt" <scdbackup@gmx.net>]

Hi,

(i wonder why the original mail from Dietmar Maurer does
 not show up in grub-devel archives or my mailbox)

Dietmar Maurer wrote:
> > After reverting the following commit everything works again:
> > http://git.savannah.gnu.org/cgit/grub.git/commit/?id=cf47a2fba5852014bc59959c5e357e8313933414

Andrei Borzenkov wrote:
> It chokes on -V which is "display version and exit" in argp.

Alternative -as mkisofs option:  -volid 'PVE'

With old grub-mkrescue(.in) of 1.99, the version option was -v,
which would collide with the -as mkisofs option which has as alias
the word "-verbose".


> I still
> believe this patch was mistake; it leaves no possibility to
> disambiguate between grub and external options.

So we are back at the reasons why i proposed to introduce
a new tool  grub-mkiso.c  with clear distinction of arguments
for grub-mkiso and xorriso, and to have an artlessly implemented
but high-fidelity compatibility mode for emulating old
grub-mkrescue(.in).

My proposal of such an artless shell-to-C translation is posted as

  http://lists.gnu.org/archive/html/grub-devel/2014-10/msg00000.html

(Dietmar's command line would be for new grub-mkiso then.)


----------------------------------------------------------------
Some xorriso musings:

Dietmar Maurer wrote:
> > # grub-mkrescue -o pve-cd.iso data-gz -- -z -r -V 'PVE' -c boot/boot.cat
> > -isohybrid-gpt-basdat -partition_offset 16 -c boot/boot.ca

This seems to be mangled a bit. Especially the double
option -c. Were there more options ?

-isohybrid-gpt-basdat might collide with xorriso options
used by grub-mkrescue. (It is intended for ISOLINUX/GRUB2
BIOS/EFI hybrids. E.g. debian-7.7.0-amd64-netinst.iso.)

-partition_offset 16 is not really compliant with UEFI specs,
which prescribe a single MBR partition starting at block 1,
if GPT is present.
The whole ISOLINUX/GRUB2 isohybrid world does not care about
that prescription. But grub-mkrescue does.

To save some intermediate disk space:
The generic xorriso command
  -set_filter_r --zisofs ...paths.in.iso... --
can do the mkzftree(1) compression on the fly, if libz is
linked in.


Have a nice day :)

Thomas