Emacs: Auto Backup~ (tilde postfix)
disable emacs automatic backup~ file
Emacs by default automatically creates backup files in the same dir, and with filename ending in TILDE ~.
To turn it off, put this in your Emacs Init File:
(setq make-backup-files nil) ;; default is t
Multi Backup (Whenever File is Saved)?
Emacs only make one backup, when file is changed for first time, not every save.
There is no simple config to make emacs do a backup whenever file is saved.
You have to add a
Hook
to
save-buffer.
[see Emacs: Backup Current File 📜]
backup into one folder
Put this in your Emacs Init File:
;; backup into one flat dir (setq backup-directory-alist '(("." . "~/.emacs.d/backup/"))) ;; example ;; file ;; /A/B/C/ff.txt ;; backup root dir ;; ~/.emacs.d/backup ;; backup at ;; ~/.emacs.d/backup/A!B!C!ff.txt~
stop emacs backup changing the file's creation date of the original file
Put this in your Emacs Init File:
(setq backup-by-copying t)
Explanation: when emacs does a backup, by default it renames the original file into the backup file name, then create a new file and insert new file content into it. This effectively destroys the creation date of your file. (If a file is created in 2001, and you modified it today, the file's creation date will become today.
Note: unixes (including Linux and BSD) do not record file creation date, so this doesn't matter. (ctime is not creation date.) Microsoft Windows and Mac OS X do record file creation date.).
All Configurations for Backup
Here are all configurations for backup.
(setq make-backup-files t) ;; make backup name incremental by number, ending in ~1~ ~2~ etc ;; note: only one backup is made when file is changed for first time, not every save (setq version-control nil) ;; make sure hard link and creation date, owner, etc is preserved (setq backup-by-copying t) ;; make backup even in git controlled dir (setq vc-make-backup-files t) ;; silently delete old backup (setq delete-old-versions t) ;; (setq kept-old-versions 2) ; default 2 ;; (setq kept-new-versions 2) ; default 2 ;; function that decide a file should be backed up ;; (setq backup-enable-predicate 'normal-backup-enable-predicate ) ;; a alist (regex . dir) to decide where to place backup ;; (setq backup-directory-alist '(("." . "~/.emacs.d/backup")))