the purpose of locale.alias

[Bruno Haible <bruno@clisp.org>]

Hi,

What is the purpose of glibc's locale.alias, typically installed as
/usr/share/locale/locale.alias ? (I'm not talking about the X11 locale.alias
here.)

I would like to suggest to improve the comments in it, to clarify its
purpose.

* The comments so far say:
  "
   # Note: This file is obsolete and is kept around for the time being for
   # backward compatibility.  Nobody should rely on the names defined here.
   # Locales should always be specified by their full name.
  "
  And indeed, while nowadays most GNU/Linux users use locales with UTF-8
  encoding, all of the aliases in the current locale.alias file are for
  locales with traditional encodings; they are thus not useful today any more.

* But a valid future use of locale.alias is when a language code changes
  (like in the past: no -> nb, or iw -> he), or when a country code changes
  (like in the past with Yugoslavia or Soviet Union). Such changes can happen
  in the future, and for people who use a rolling-release distribution and
  use locale names in their .profile script, it is useful to be able to
  add a line
     ll_oldCC.UTF-8    ll_newCC.UTF-8
  to the locale.alias file.

* Then there are also people who "want to unify language codes on all
  environments" [1]. This sounds like of minor importance to me. Do you
  think this is a reasonable use-case of locale.alias or not?

Other purposes, that I have missed?

Bruno

[1] https://askubuntu.com/questions/883622/