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From: Godmar Back <godmar@gmail.com>
Date: Wed, 26 Jan 2022 19:35:41 -0500
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Subject: why does `LANG` not influence the locale in GNU/Linux
To: William Tambe via Libc-help <libc-help@sourceware.org>
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If I am writing code that uses fgetwc to read from standard input, I
need to call setlocale(LC_CTYPE, "en_US.utf8"); to ensure that fgetwc
will treat stdin as a UTF-8 encoded stream.  This property appears to
hold (on Ubuntu 20, with default GNU libc), independent of the setting
of LANG.  LANG is set to en_US.utf8.

By contrast, Python 3 changes its behavior with regard to the encoding
it assumes sys.stdin to be in based on the LANG variable - if set to
en_US.utf8, it'll decode as UTF-8, if set to C or unset, it'll treat
the input as 8-bit ASCII encoding (I believe).

My question is why GNU libc (chose?) to not use LANG and what
standards, if any, apply here.
Is my characterization of the behavior correct?

 - Godmar