quoth Viktor Dukhovni
Or better yet, "unset LC_ALL", no point it having an empty setting. On a Fedora 31 system, locale(7) states:
If the second argument to setlocale(3) is an empty string, "", for the default locale, it is determined using the following steps:
1. If there is a non-null environment variable LC_ALL, the value of LC_ALL is used.
2. If an environment variable with the same name as one of the categories above exists and is non-null, its value is used for that category.
3. If there is a non-null environment variable LANG, the value of LANG is used.
Where by "non-null", the author must have meant non-empty, since the value of an environment variable (that has a value) cannot be NULL, but it can be empty.
Yes, that's what null means in this context - zero length. I would think the main question is whether other applications are going to be affected by a change to LC_ALL. If that's in doubt, it may be more convenient to apply this as he has done in his examples, on the command line. Donn