pausch@uvacs.cs.Virginia.EDU (Randy Pausch) (01/19/89)
Is there any way to change the way GNUemacs names backup files? File
name completion in the ksh makes it a real pain to have the backup of
'foo' be in 'foo~'; optimally, I'd like GNUemacs to make a directory
that contains backup files, but I'd settle for backing up 'foo' in
'BAK.foo' or the like. Any ideas?
thanks,
pausch@virginia.edumike@arizona.edu (Mike Coffin) (01/19/89)
From article <2926@uvacs.cs.Virginia.EDU>, by pausch@uvacs.cs.Virginia.EDU (Randy Pausch):
> Is there any way to change the way GNUemacs names backup files?
Yes. Change the function find-backup-file-name to do whatever you
want. I prefer to prepend a "." on the front so that ls doesn't show
backups, so the following is in my .emacs file:
------------------------------------------------------------------------
;;; changed from original to put `.' before name of backup version
(defun find-backup-file-name (fn)
"Find a file name for a backup file, and suggestions for deletions.
Value is a list whose car is the name for the backup file
and whose cdr is a list of old versions to consider deleting now."
(if (eq version-control 'never)
(list (concat fn "~"))
(let* ((base-versions (concat "." (file-name-nondirectory fn) ".~"))
(bv-length (length base-versions))
(possibilities (file-name-all-completions
base-versions
(file-name-directory fn)))
(versions (sort (mapcar 'backup-extract-version possibilities)
'<))
(high-water-mark (apply 'max (cons 0 versions)))
(deserve-versions-p
(or version-control
(> high-water-mark 0)))
(number-to-delete (- (length versions)
kept-old-versions kept-new-versions -1)))
(if (not deserve-versions-p)
(list (concat fn "~"))
(cons
(concat (file-name-directory fn)
"."
(file-name-nondirectory fn)
".~"
(int-to-string (1+ high-water-mark)) "~")
(if (> number-to-delete 0)
(mapcar
(function (lambda (n)
(concat
(file-name-directory fn)
"."
(file-name-nondirectory fn)
".~" (int-to-string n) "~")))
(let ((v (nthcdr kept-old-versions versions)))
(rplacd (nthcdr (1- number-to-delete) v) ())
v))))))))
--
Mike Coffin mike@arizona.edu
Univ. of Ariz. Dept. of Comp. Sci. {allegra,cmcl2}!arizona!mike
Tucson, AZ 85721 (602)621-2858Ram-Ashwin@cs.yale.edu (Ashwin Ram) (01/20/89)
In article <8776@megaron.arizona.edu>, mike@arizona.edu (Mike Coffin) writes: > From article <2926@uvacs.cs.Virginia.EDU>, by pausch@uvacs.cs.Virginia.EDU (Randy Pausch): > > Is there any way to change the way GNUemacs names backup files? > > Yes. Change the function find-backup-file-name to do whatever you > want. Hmmm... an 'apropos' on 'backup' reveals: find-backup-file-name: Find a file name for a backup file, and suggestions for deletions. Value is a list whose car is the name for the backup file and whose cdr is a list of old versions to consider deleting now. and: make-backup-file-name: Create the non-numeric backup file name for FILE. This is a separate function so you can redefine it for customization. Why are there two functions? Does one call the other? Which is the right one to redefine for customization? -- Ashwin.
jr@bbn.com (John Robinson) (01/20/89)
In article <47991@yale-celray.yale.UUCP>, Ram-Ashwin@cs (Ashwin Ram) writes: >Hmmm... an 'apropos' on 'backup' reveals: > > find-backup-file-name: > >and: > > make-backup-file-name: > >Why are there two functions? Does one call the other? Which is the right >one to redefine for customization? A find-emacs-tag on one of these gets you to files.el, which has: (defun make-backup-file-name (file) "Create the non-numeric backup file name for FILE. This is a separate function so you can redefine it for customization." (concat file "~")) ;[... other defun deleted] (defun find-backup-file-name (fn) "Find a file name for a backup file, and suggestions for deletions. Value is a list whose car is the name for the backup file and whose cdr is a list of old versions to consider deleting now." (if (eq version-control 'never) (list (make-backup-file-name fn)) (let* ((base-versions (concat (file-name-nondirectory fn) ".~")) (bv-length (length base-versions)) ;... So the former (of Ashwin's list) calls the latter. Redefining the former is sufficient, unless you want to change the way version-controlled backups look. Version-control creates file versions using backups of the form foo.~1~, foo.~2~, etc. foo~ is linked to the most recent backup. More in the manual. I think version-control will someday be part of GNU (the operating system), so changing the form of these files if you use them may be a little more serious departure from common practice. -- /jr jr@bbn.com or bbn!jr
mike@arizona.edu (Mike Coffin) (01/20/89)
From article <47991@yale-celray.yale.UUCP> by Ram-Ashwin@cs.yale.edu: > Hmmm... an 'apropos' on 'backup' reveals: > find-backup-file-name: [...] > and: > make-backup-file-name: [...] > Why are there two functions? Does one call the other? Which is the right > one to redefine for customization? A quick look at the source reveals that find-backup-file-name calls make-backup-file-name. The latter is the one to change; I should have looked before I shot my mouth off. In my defense, I did the modifications to find-backup-file-name quite a while ago; at that time it did the file-name creation in-line. Since it kept working, I never noticed that there's now an easier way to do it. The right way to do things now is to just fix make-backup-file-name. -- Mike Coffin mike@arizona.edu Univ. of Ariz. Dept. of Comp. Sci. {allegra,cmcl2}!arizona!mike Tucson, AZ 85721 (602)621-2858