Re: etags name collision.

[Ulrich Mueller <ulm@gentoo.org>]

>>>>> On Mon, 11 Apr 2022, Eli Zaretskii wrote:

>> Rather than "install vs not-install" the test could decide "install as
>> `ctags` vs install as `somethingelse`", which is closer to having our
>> cake and eating it too since the user can then have both installed at
>> the same time.

> No, the intent is exactly to let users have the program they want
> under the name "ctags".  Everything else, including renaming, is left
> to the users themsleves, because we have no way of second-guessing
> their habits.  And as someone else pointed out, we already support
> installing under a different name, if the user knows what is that
> name.

+1

There already are autoconf's --program-prefix, --program-suffix and
--program-transform-name options which can do everything that is needed.

For example, Gentoo uses these configure options to install Emacs' ctags
as (e.g.) "ctags-emacs-28". Exuberant/universal ctags is installed as
"exuberant-ctags". "ctags" is a symlink to one of them and can be
updated by the user.

>> Still, an install-time test has the downside that it won't adapt if
>> `ctags` is installed after Emacs is built/installed, as is probably the
>> case for most users nowadays (who don't build Emacs themselves but
>> install from a distro or from our prebuilt tarballs).

I tend to agree. From a distro point of view, testing for an installed
ctags binary (with the purpose to avoid file name collisions) is not
helpful. The set of files in the installed image should not depend on
random factors like package installation order.

> I don't think we need to make too much out of it.  the problem is
> easily solved manually, so we just make it a tad easier in one simple
> use case.