Set default coding system = UTF-8

Question

Windows 10 (64 bit), Emacs 25.1

I want when I save any file to save them (by default) with coding system = UTF-8.

So In my init.el I has :

(prefer-coding-system 'utf-8)
(set-default-coding-systems 'utf-8)
(set-language-environment 'utf-8)
(set-selection-coding-system 'utf-8)

But it not help. When I try to save file (C-x C-s) Emacs prompt me: "Select coding system"

Answer 1

This does it for me:

(set-language-environment "UTF-8")

See here.

Answer 2

I do not know if this can be of help, but I will mention it anyway. When working (mainly in source LaTeX files) with my colleagues who use a different coding system, nothing I did could persuade Emacs to always read (or save) with the desired encoding. I found that the only safe way was to add as a first line something like:

% -*- coding: iso-8859-15 -*-

starting in column 1. You can set the encoding you prefer there, and Emacs will save (or read) with the prescribed encoding.

Answer 3

You could try M-x customize then Environment > Keyboard > Keyboard Coding System The docs say "This is set at startup based on locale." which may also point you in the direction of what variable to set.