Re: Why aren't char bits portable?

[Daniel L. Weinreb <DLW@QUABBIN.SCRC.Symbolics.COM>]

I agree with everything you say in your message, except that I would
modify the conclusion somewhat.  I believe that the intent of including
"bits" in the standard is to allow for the fact that some of the "bits"
are gaining some amount of currency as ad hoc standards.  In particular,
there are now several terminals on the market that have a "Meta" key,
which is used by many Emacs-family editors.  (The Ann Arbor Ambassador
and the Teleray something (2000?) come to mind.)

A program that wants to be universally portable, of course, cannot
depend on the presence of such key on the user's keyboard.  However, it
is not hard to imagine a program that wants to be portable, but also
wants to allow any user who has a Meta key to take advantage of it.
(Indeed, many Emacs-family editors have this property.)

I believe the intention of the "bits" feature was to help out such
programs.  While I'm not sure that all the details of the "bits" feature
in the standard are ideal, nevertheless I wanted to point out that the
entire feature is not necessarily bankrupt.