Re: Retrieving the "include" directory for Emacs Modules

[Eli Zaretskii <eliz@gnu.org>]

> From: Marco Antoniotti <marcoxa@gmail.com>
> Date: Mon, 9 Dec 2024 10:58:57 +0100
> 
> On my Mac, If I install emacs as a "formula" (i.e., not a s an app) things
> seem installed as they should be.  OTOH the brew "cask" (which installs a
> .app in the Application directory) seems to create something that Apple
> likes, but that STILL may be told to have a pointer to the include
> directory as it does to the data-directory.
> 
> This is obviously something that the brew folks should deal with, but the
> notion of having a variable that tracks the include directory still has
> merit.  At least as an extra guideline to people like the brew maintainers.

As I tried to explain, if emacs-module.h is not installed in its
intended place, we cannot know where it is installed.  We only know
that from the default installation locations we have in our Makefiles,
but if some distros modify that, we cannot know.

And I still contend that the correct installation should put this file
where all the other header files are, and then the compiler will
always find it.  Users who don't want to fight the uphill battle
against brew could simply copy the file to the compiler's include
directory, and be done.