How to configure GNU Emacs to write UNIX or DOS formatted files by default?

Question

I\'ve had these functions in my .emacs.el file for years:

(defun dos2unix ()
  \"Convert a DOS formatted text buffer to UNIX format\"
  (interac         


        

Answer 1

I've got a bunch of these in my .emacs:

(setq-default buffer-file-coding-system 'utf-8-unix)
(setq-default default-buffer-file-coding-system 'utf-8-unix)
(set-default-coding-systems 'utf-8-unix)
(prefer-coding-system 'utf-8-unix)

I don't know which is right, I am just superstitious.

Answer 2

I up-voted question and answer, but spent a couple minutes possibly improving on the info, so I'll add it.

First, I checked documentation on each variable and function in user181548's answer, by (first cutting and pasting into Emacs, then) putting cursor over each, and typing C-h v RET and C-h f RET respectively.

This suggested that I might only need

(prefer-coding-system 'utf-8-unix) 

Experimenting with the other lines didn't seem to change pre-existing buffer encodings (typing C-h C RET RET to check (describe-coding-system) and g each time to refresh), so I omitted the other lines and made a key-binding to quickly change any old files that were still DOS, that is,

(defun set-bfr-to-8-unx ()
  (interactive)
  (set-buffer-file-coding-system
   'utf-8-unix)
  )
(global-set-key (kbd "C-c u") 
        'set-bfr-to-8-unx
        )

For the curious, to discover the 3rd and 4th line of above function, (set-buffer-file-coding-system 'utf-8-unix), I used C-x RET f RET to manually change the current buffer's encoding, then M-x command-history RET to see how those keys translate to code.

Now maybe my git commit's will stop whining about CRs.