[Bug-tar] option --portability not recognized

[Bruno Haible]

Hi,

With tar-1.23, "tar --help" says in particular:

      --old-archive, --portability
                             same as --format=v7

But these options are not recognized:

  $ tar cf - -C /mnt --old-archive . > /dev/null 
  tar: --old-archive: (PROGRAM ERROR) Option should have been recognized!?
  Try `tar --help' or `tar --usage' for more information.

  $ tar cf - -C /mnt --portability . > /dev/null 
  tar: --old-archive: (PROGRAM ERROR) Option should have been recognized!?
  Try `tar --help' or `tar --usage' for more information.

Bruno