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Every-time I have to install a new Debian Linux system I encounter the same troubles with locales -- I do precisely want English system language with standards set to the country where I live, i.e. Germany.
debian installer, and probably others, is asking at installation time for your "preferred" language. And every time I choose English. But then, I cannot add the standard locales of my country, because only English speaking countries are shown for the previously chosen language.
It's clear. After installation with enough manual fiddling it's achievable. And there is also a workaround (at least for European-ish users) by using
en_DK.UTF-8 described here. However, this doesn't answer the question: Why it is so difficult to combine the preferred English system language with specific locales? I want to understand the reason/s and if there are any risks.
(Why do I want this? Because I can't see any advantage in (partially) traduced messages and software. Even more, it is much harder to find help when researching with English-foreign errors and messages got for the encountered issues.)
My actual configuration, AFAIK it works fine:
$ locale LANG=en_US.UTF-8 LANGUAGE= LC_CTYPE="en_US.UTF-8" LC_NUMERIC="en_US.UTF-8" LC_TIME="en_US.UTF-8" LC_COLLATE="en_US.UTF-8" LC_MONETARY=de_DE.UTF-8 LC_MESSAGES="en_US.UTF-8" LC_PAPER=de_DE.UTF-8 LC_NAME=de_DE.UTF-8 LC_ADDRESS=de_DE.UTF-8 LC_TELEPHONE=de_DE.UTF-8 LC_MEASUREMENT=de_DE.UTF-8 LC_IDENTIFICATION=de_DE.UTF-8 LC_ALL=