gnu emacs backup files Ryan Barrett <snarfed at ryanb dot org> 2003-01-01T05:00:00Z en text/html Copyright 2002-2009 Ryan Barrett

/space/gnu.jpg

I use GNU Emacs, and I love it. However, one annoyance is that it scatters autosave files (#foo#) and backup files (foo~) all over the filesystem.

So, I finally got fed up with this, and figured out how to keep them all in one place. Here's the elisp (GNU Emacs only) that I put in my .emacs:

;; Put autosave files (ie #foo#) in one place, *not*
;; scattered all over the file system!
(defvar autosave-dir
 (concat "/tmp/emacs_autosaves/" (user-login-name) "/"))

(make-directory autosave-dir t)

(defun auto-save-file-name-p (filename)
  (string-match "^#.*#$" (file-name-nondirectory filename)))

(defun make-auto-save-file-name ()
  (concat autosave-dir
   (if buffer-file-name
      (concat "#" (file-name-nondirectory buffer-file-name) "#")
    (expand-file-name
     (concat "#%" (buffer-name) "#")))))

;; Put backup files (ie foo~) in one place too. (The backup-directory-alist
;; list contains regexp=>directory mappings; filenames matching a regexp are
;; backed up in the corresponding directory. Emacs will mkdir it if necessary.)
(defvar backup-dir (concat "/tmp/emacs_backups/" (user-login-name) "/"))
(setq backup-directory-alist (list (cons "." backup-dir)))


...and, courtesy of Amit Patel, here's the elisp for XEmacs.

;;; Auto-save
;;; Load the auto-save.el package, which lets you put all of your autosave
;;; files in one place, instead of scattering them around the file system.
;;; M-x recover-all-files or M-x recover-file to get them back
(defvar temp-directory (concat "/tmp/" (user-login-name)))
(make-directory temp-directory t)

; One of the main issues for me is that my home directory is
; NFS mounted.  By setting all the autosave directories in /tmp,
; things run much quicker
(setq auto-save-directory (concat temp-directory "/autosave")
      auto-save-hash-directory (concat temp-directory "/autosave-hash")
      auto-save-directory-fallback "/tmp/"
      auto-save-list-file-prefix (concat temp-directory "/autosave-")
      auto-save-hash-p nil
      auto-save-timeout 100
      auto-save-interval 300)
(make-directory auto-save-directory t)
(require 'auto-save)

;;; Put backups in another directory.  With the directory-info
;;; variable, you can control which files get backed up where.
(require 'backup-dir)
(setq bkup-backup-directory-info
      `(
        (t ,(concat temp-directory "/backups") ok-create full-path)
        ))
(setq make-backup-files t)
(setq backup-by-copying t)
(setq backup-by-copying-when-mismatch t)
(setq backup-by-copying-when-linked t)
(setq version-control t)
(setq-default delete-old-versions t)


http://snarfed.org/ gnu emacs backup files-1 Guest cmt_pubDate text/html Thanks a ton! that sure is helpful!

- Sandeep http://snarfed.org/ gnu emacs backup files traneHead cmt_pubDate text/html Thank you!! http://snarfed.org/ gnu emacs backup files Christian Betz cmt_pubDate text/html You rule! http://snarfed.org/ gnu emacs backup files Jacob cmt_pubDate text/html Finally, a script that makes this simple.

Thank you. http://snarfed.org/ gnu emacs backup files Justin cmt_pubDate text/html That's awesome... saves me a lot of hassle http://snarfed.org/ gnu emacs backup files Redtoade cmt_pubDate text/html Thanks a ton!
Nuisance gone.

What's the reason behind different scripts for XEmacs and GNU Emacs?  I knew that the two don't play nice, but I'm surprised that the .el files are tailored for one or the other.

Can't wait to see how they work on EmacsW32! http://snarfed.org/ gnu emacs backup files Ryan cmt_pubDate text/html good point! they're different because i only wrote the gnu emacs elisp. i provided amit's xemacs elisp for completeness and convenience only.

having said that, the gnu emacs code evaluates happily in xemacs, so it just might work. amit's code, on the other hand, uses auto-save.el, which comes with xemacs but not gnu emacs. it might be a better solution, but it's xemacs-specific. http://snarfed.org/ gnu emacs backup files Redtoade cmt_pubDate text/html It's amazing how such a simple piece of code eliminates such a pain in the butt problem.  Thanks again.

I have been thinking though.  (No good deed and what not...)

I use individual .emacs files per user.  Each user adds your snippet.  Therefore, without any alterations, each user gets a (user-login-name) added to both the /tmp/emacs_backups and /tmp/emacs_autosaves.

For me, these files are made with the default mask in bash, I guess.  So they get permissions of 755.  No matter what the original file was.  Since /tmp is a public directory, now anyone can read the backups.
This might be a security risk.

I'm no bash expert.  So I'm no help.  Sorry.

Thanks again. http://snarfed.org/ gnu emacs backup files Arthur cmt_pubDate text/html I had a problem where emacs would try and auto-save files to /tmp/emacs_autosaves/arthur//home/arthur/scratch or similar directories. Emacs could not open the file because the directories did not exist. I fixed it by changing make-auto-save-file-name to not add paths to non-file buffers. I'm not where why that was there in the first place.

(defun make-auto-save-file-name ()
  (concat autosave-dir
  (if buffer-file-name
  (concat "#" (file-name-nondirectory buffer-file-name) "#")
  (concat "#%" (buffer-name) "#"))))


Thanks for the script. http://snarfed.org/ gnu emacs backup files Amir cmt_pubDate text/html Thanks a lot for the script. http://snarfed.org/ gnu emacs backup files Mike cmt_pubDate text/html It seems that putting them in a central directory puts bangs (!)'s in the file name.  How can you restore a backup in this case, given that ! is a control character in *nix? http://snarfed.org/ gnu emacs backup files ryan cmt_pubDate text/html hmm, i don't understand what you mean by "control character in *nix." do you mean it's a control character in your shell? just quote the filename - cat "/tmp/bang!file" - or escape the ! - cat /tmp/bang\!file. http://snarfed.org/ gnu emacs backup files Noam cmt_pubDate text/html I used this code for a while, it works but causes error message in mail buffers. After some investigation I think that this code does the Wrong Thing. The default implementation of make-auto-save-file-name is much more sophisticated, and it uses the variable auto-save-file-name-transforms which allows the user to change the outcome without redefining functions.

(setq auto-save-file-name-transforms `(("\\(?:[^/]*/\\)*\\(.*\\)" ,(concat autosave-dir "\\1") t)))

Acheives the same goal as the defuns, without breaking autosaves for gnus or tramp. http://snarfed.org/ gnu emacs backup files sam17 cmt_pubDate text/html Thanks for this little tool.

It helped me at work where non emacs users colleagues complains about all these little files... http://snarfed.org/ gnu emacs backup files Tushar cmt_pubDate text/html Thanks dude ! This is really helpful ! All those crap files are gone ! :-) http://snarfed.org/ gnu emacs backup files 164747 cmt_pubDate text/html Thank you!
This has been haunting me for years. If one wants to save other users on the system from this plague, you can copy the above code to /etc/emacs/site-start.el instead of into to ~/.emacs file. http://snarfed.org/ gnu emacs backup files G. Georgiev cmt_pubDate text/html Thanks!
For years I did just live with that nuisance - in reality small one considering all the functionality that Emacs offers! - but it is better now. - George. http://snarfed.org/ gnu emacs backup files David McCracken cmt_pubDate text/html setq auto-save-file-name-transforms only works for the auto-save (#) files. The default make-backup-file-name function, defined in files.el, invokes make-backup-file-name-1, which embeds the !path! file name synthesis so there is no way to change these long names for backup (~) files without completely replacing make-backup-file-name function. To shrink auto-save names, the last element of auto-save-file-name-transforms should be nil instead of t. Also, note that the RE is for DOS. For LINUX I use:
(setq auto-save-file-name-transforms `(("\\([^/]*/\\)*\\(.*\\)", "~/bak/\\2" nil))) making auto-saves userhome\bak\#filename#. http://snarfed.org/ gnu emacs backup files Tubo cmt_pubDate text/html Thanks a lot!
Wonderful work! http://snarfed.org/ gnu emacs backup files Vikraman cmt_pubDate text/html Thanks! http://snarfed.org/ gnu emacs backup files Memnon cmt_pubDate text/html I don't get it.
So many people seem to have 'just lived' with it.
Everyone: The /info/ is right there, it is even
in the FAQ. 'C-h i' at your service:
,----[ (info "(efaq)Disabling backups") ]
|  Beginning with Emacs 21.1, you can control where Emacs puts backup
| files by customizing the variable `backup-directory-alist'.  This
| variable's value specifies that files whose names match specific patters
| should have their backups put in certain directories.  A typical use is
| to add the element `("." . DIR)' to force Emacs to put all backup
| files in the directory `dir'.
`---- http://snarfed.org/ gnu emacs backup files ryan cmt_pubDate text/html uh, did you read the post? that's what it does. the big extra chunk of elisp at the beginning is for autosave files, not backups.