If I have two files, a.txt containing:
meow ✓ bar
and b.txt containing:
meow ⨯ bar
Why can’t the GNU Coreutils command comm tell the difference between the two when $LANG is set to a UTF-8 encoding?
$ LANG=C comm a.txt b.txt
meow ✓ bar
meow ⨯ bar
$ LANG=en_US comm a.txt b.txt
meow ✓ bar
meow ⨯ bar
$ LANG=en_US.UTF-8 comm a.txt b.txt
meow ⨯ bar
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