Re: grub-mkrescue problems in argp_parse

[Thomas Schmitt]

Hi,

> We need for compatibility:
> -o
> --output

This is an intentional interference because grub-mkrescue -o
is supposed to overload mkisofs -o.
--output is not a mkisofs alias of -o, but rather -output.

So in order to keep grub-mkrescue users from circumventing
the overloading, grub-mkrescue should accept -output as alias
of -o and --output.


> -?

Yikes ! You can have that one.

> -d

Used in old mkisofs.
"Do not add trailing dot to ISO file names without dot."
An alias is available: -omit-period

> -k

Seems to be unused in traditional mkisofs and genisoimage.
I do not add single-letter options on my own.


> --rom-directory
> ...
> --verbose

Not in use yet by xorriso resp. xorriso -as mkisofs .
Some of the option names are quite unspecific, though.


> In future we can make a rule to add only options starting with --.

This will not really create clarity because i already added
options with "--" to -as mkisofs. Mainly to get out of
the way of future mkisofs extensions. The current option
set of xorriso -as mkisofs is strictly irregular.

The generic command interpreter of xorriso ignores leading '-'
completely and maps inner '-' to underscores '_'.
I.e.  set_filter_r , ----set-filter_r, --set-filter-r
are all recognized as valid command -set_filter_r.
(The interpreter can afford this because it is always aware
 when the next word is supposed to be a command.)
 

> > --modules --grub-mkimage --override-directory
> > Will they be re-introduced ? (Should they ? What did they do ?)
> They're there. If you have data suggesting otherwise, please detail it

You are right. I did not see them in
  http://git.savannah.gnu.org/cgit/grub.git/tree/util/grub-mkrescue.c
but now found them in
  http://git.savannah.gnu.org/cgit/grub.git/tree/include/grub/util/install.h
  http://git.savannah.gnu.org/cgit/grub.git/tree/util/grub-install-common.c

(Would it be ok and sufficient to call grub_install_parse ()
 from my proposed legacy parser when it encounters one of
 the three options ?)


---------------------------------------------------------

I have now made a file with the reserved option/command
names. Hopefully i remember to check it when i introduce
new names. (If not, i will have to solve collisions by
introducing aliases and deprecating my bad choices.)

Nevertheless i doubt that it is a good idea to stick for
future development with the implicit distinction between
arguments for grub-mkrescue and for xorriso.
This has potential for recurrent pain.


Have a nice day :)

Thomas