For Debian this article is either outdated, or incorrect. (It might be true for Ubuntu; I haven’t tested that.)
View/set global locale for all users on a Debian or Ubuntu Linux
To see which locales are supported on Debian/Ubuntu, enter:
$ locale -a|more
To set the locales for all users, enter:
$ sudo locale-gen en_IN $ sudo locale-gen en_IN.UTF-8
On Debian, at least for Stretch, this isn’t how local-gen works. It does not take locales as arguments. Rather it opens /etc/local.gen and reads it to get the list of locales it should make.
I’m new to NixCraft, and can’t see how to directly comment on this article, so am posting here, in hopes that this web page will be updated.
Debian Stretch 9.6 (x86-64), Linux kernel 4.9.0-8-amd64