Variable: ediff-backup-specs

ediff-backup-specs is a customizable variable defined in ediff-ptch.el.gz.

Value

"-z.orig -b"

Documentation

Backup directives to pass to the patch program.

Ediff requires that the old version of the file (before applying the patch) be saved in a file named the-patch-file.extension. Usually extension is
.orig, but this can be changed by the user and may depend on the system.
Therefore, Ediff needs to know the backup extension used by the patch program.

Some versions of the patch program let you specify -b backup-extension. Other versions only permit -b, which assumes the extension .orig
(in which case ediff-backup-extension MUST be also .orig). The latest
versions of GNU patch require -b -z backup-extension.

Note that both ediff-backup-extension and ediff-backup-specs must be set properly. If your patch program takes the option -b, but not -b extension, the variable ediff-backup-extension must still be set so Ediff will know which extension to use.

Ediff tries to guess the appropriate value for this variables. It is believed to be working for traditional patch, all versions of GNU patch, and for POSIX patch. So, don't change these variables, unless the default doesn't work.

Source Code

;; Defined in /usr/src/emacs/lisp/vc/ediff-ptch.el.gz
(defcustom ediff-backup-specs
  (let ((type (ediff-test-patch-utility)))
    (cond ((eq type 'gnu)
	   ;; GNU `patch' v. >= 2.2
	   (format "-z%s -b" ediff-backup-extension))
	  ((eq type 'posix)
	   ;; POSIX `patch' -- ediff-backup-extension must be ".orig"
	   (setq ediff-backup-extension ediff-default-backup-extension)
	   "-b")
	  (t
	   ;; traditional `patch'
	   (format "-b %s" ediff-backup-extension))))
  "Backup directives to pass to the patch program.
Ediff requires that the old version of the file \(before applying the patch)
be saved in a file named `the-patch-file.extension'.  Usually `extension' is
`.orig', but this can be changed by the user and may depend on the system.
Therefore, Ediff needs to know the backup extension used by the patch program.

Some versions of the patch program let you specify `-b backup-extension'.
Other versions only permit `-b', which assumes the extension `.orig'
\(in which case ediff-backup-extension MUST be also `.orig').  The latest
versions of GNU patch require `-b -z backup-extension'.

Note that both `ediff-backup-extension' and `ediff-backup-specs'
must be set properly.  If your patch program takes the option `-b',
but not `-b extension', the variable `ediff-backup-extension' must
still be set so Ediff will know which extension to use.

Ediff tries to guess the appropriate value for this variables.  It is believed
to be working for `traditional' patch, all versions of GNU patch, and for POSIX
patch.  So, don't change these variables, unless the default doesn't work."
  :type 'string)