Re: Bug#793067: Bug#792328: info: can no longer find the Emacs manual

[Gavin Smith]

On 4 August 2015 at 14:35, Eli Zaretskii <address@hidden> wrote:
>> Then there would only be one "foo.info" manual reachable for
>> each element in PATH (those other than the first can be accessed with
>> "info --all foo"). This means that "info foo" can only give the manual
>> for a particular version of foo if there is an executable called "foo"
>> somewhere in the PATH (assuming a sensible setup). Otherwise you'd
>> have to do "info foo-12.34" instead. This relegates that manual to a
>> second-class status, but that isn't too bad, because the corresponding
>> executable is also second-class when it comes to the shell finding it.
>
> This would make many "second-class" manuals, because there are
> actually many manuals that don't correspond to any executable.  To
> name just a few, there are no executables named 'texinfo' or 'elisp'
> or 'coreutils' or 'gccint'.  So adopting this path will just confuse
> users, because "info emacs" will magically work, while "info elisp"
> won't.

That's not exactly what I meant.

Suppose there are two emacs installations, one as /usr/bin/emacs,
which is Emacs 23, and the other /usr/local/bin/emacs, which is Emacs
24. Then there'd be /usr/share/info/{elisp.info,emacs.info},
describing Emacs 23, and
/usr/local/share/info/{elisp.info,emacs.info}, describing Emacs 24. If
INFOPATH=PATH and /usr/bin is first in the PATH, then "info emacs" and
"info elisp" would both give the Emacs 23 versions. To get the Emacs
24 versions, you'd have to either do "info --all emacs" and "info
--all elisp" and select the right option from the menu, or do "info
/usr/local/share/info/emacs.info". With the feature to prefer the
current Info directory (not implemented yet), jumping back and forth
via cross-references between the emacs and elisp manuals for the same
versions of emacs would work.

What would not work would be if there were many emacs versions all
installed in the same hierarchy:
/usr/bin/{emacs-20,emacs-21,emacs-22}. The corresponding Info files,
if they were installed the way I suggested, would be called
/usr/share/info{emacs-20.info,emacs-21.info,emacs-22.info} and would
not be identifiable to the Info browser as being the manual called
"emacs", or "elisp". That's why I said those manuals would have a
second-class status. But they would still be accessible with, e.g.
"info elisp-22".