Re: installing emacs and X11 on OS X

[Hugo Wolf <hwolf@deutsches.lieder.net>]

In article <mailman.1035784882.23705.help-gnu-emacs@gnu.org>, Eli
Zaretskii wrote: 
> If there's a difference between these two configurations, there should be 
> a way to distinguish between them.  

There are actually three runtime gui environments in osx.
Distinguishing them is very easy -- window-system does it in a clean,
reliable and consistent way, and as an added bonus works in both
xemacs and gnuemacs.


> Doesn't system-configuration fit the 
> bill? or maybe system-configuration-options?

system-configuration has the same value for any emacs running in osx,
so it obviously can't be used to make any distinctions at
all. system-configuration-options can currently distinguish in a very
ugly way between an emacs that was _built_ with mac-windowing support
and one that wasn't but of course says nothing at all about whether or
not it's actually _running_ in that window system at any given time.

By definition, build-time options can't work as a way to discover
runtime distinctions. This or that individual runtime feature doesn't
work either. To think about it that way is to misunderstand the nature
of a gui environment.  What we're talking about here is not at the
level of "do I have color available".  It's at the level of "do I want
to follow Mac l&f".

You're obviously a very knowledgeable emacs guy and even you don't
seem to be able to find anything other than window-system that works
for this.  Doesn't that tell you something?