missing API for locale_t in <locale.h>

[Bruno Haible]

Roland McGrath wrote:
> > In short, I'm asking for __current_locale_name to be made public. Or for
> > nl_langinfo_l to be extended to support _NL_ADDRESS_NAME, _NL_CTYPE_NAME,
> > _NL_MESSAGES_NAME, etc.
>
> I'm inclined to add to nl_langinfo for this rather than adding a new entry
> point.  Perhaps:
>
> #define _NL_LOCALE(category)		_NL_ITEM (category, 0xffff)

Yes, this would be OK.

Since macro names starting with an underscore are always understood as
"private" and "you shouldn't use", how about defining it as a macro called
NL_LOCALE or NL_LOCALE_NAME? As I understand from
  http://www.opengroup.org/onlinepubs/009695399/functions/xsh_chap02_02.html
<langinfo.h> is not allowed to define such a macro by default, but it would
be sufficient to define it if _GNU_SOURCE was specified.

> so you use nl_langinfo (_NL_LOCALE (LC_MESSAGES)).

I would then use nl_langinfo_l (_NL_LOCALE (LC_MESSAGES)), yes.

Bruno