Author: tg
Revision Date: 2021-02-07 02:02:26 UTC

early-locale-tracking: fix unsetting LANG and LC_*

if all were unset, null ("") was passed to setlocale as the locale to set;
setlocale would take this to look at the environment, and we don’t update
the shell’s own environment at all, so it would use the locale variables
that were set at startup; now it hardcodes "C" instead in those cases

Note: this also is not quite right:
• in POSIX, o̲n̲l̲y̲ the environment, not the string search, should influence
  the locale
• setting the "" locale *is* possible, but only via the environment, and
  means “the implementation-specified default locale”, which there is talk
  already about considering setting it to C.UTF-8 in… Debian? glibc? (note
  that without a call to setlocale "POSIX" is still mandated to be the one
  set at main() start)

Full locale tracking therefore must
• not set UTFMODE = isuc(ccp) before checking the POSIX locale
• update the environment variables (at least LANG, LC_CTYPE, LC_ALL) of
  the shell process itself (ugh, but doable…) and revert this ternary

Author: tg
Revision Date: 2017-07-26 23:02:23 UTC

make readonly idempotent; spotted by selk from Dragora