@c -*-texinfo-*-
@c This is part of the GNU Emacs Lisp Reference Manual.
-@c Copyright (C) 1990, 1991, 1992, 1993, 1994, 1995, 1999, 2001, 2002, 2003,
-@c 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Free Software Foundation, Inc.
+@c Copyright (C) 1990-1995, 1999, 2001-2012 Free Software Foundation, Inc.
@c See the file elisp.texi for copying conditions.
-@setfilename ../../info/backups
-@node Backups and Auto-Saving, Buffers, Files, Top
+@node Backups and Auto-Saving
@chapter Backups and Auto-Saving
@cindex backups and auto-saving
saving the buffer the first time.
If a backup was made by renaming, the return value is a cons cell of
-the form (@var{modes} . @var{backupname}), where @var{modes} are the
-mode bits of the original file, as returned by @code{file-modes}
-(@pxref{File Attributes,, Other Information about Files}), and
-@var{backupname} is the name of the backup. In all other cases, that
-is, if a backup was made by copying or if no backup was made, this
-function returns @code{nil}.
+the form (@var{modes} @var{context} @var{backupname}), where
+@var{modes} are the mode bits of the original file, as returned by
+@code{file-modes} (@pxref{File Attributes,, Other Information about
+Files}), @var{context} is a list describing the original file's
+SELinux context (@pxref{File Attributes}), and @var{backupname} is the
+name of the backup. In all other cases, that is, if a backup was made
+by copying or if no backup was made, this function returns @code{nil}.
@end defun
@defvar buffer-backed-up
should contain a single element pairing @samp{"."} with the appropriate
directory name.
-If this variable is @code{nil}, or it fails to match a filename, the
-backup is made in the original file's directory.
+If this variable is @code{nil} (the default), or it fails to match a
+filename, the backup is made in the original file's directory.
On MS-DOS filesystems without long names this variable is always
ignored.
@defopt backup-by-copying
If this variable is non-@code{nil}, Emacs always makes backup files by
-copying.
+copying. The default is @code{nil}.
@end defopt
The following three variables, when non-@code{nil}, cause the second
@defopt backup-by-copying-when-linked
If this variable is non-@code{nil}, Emacs makes backups by copying for
-files with multiple names (hard links).
+files with multiple names (hard links). The default is @code{nil}.
This variable is significant only if @code{backup-by-copying} is
@code{nil}, since copying is always used when that variable is
@end defopt
@defopt backup-by-copying-when-mismatch
-If this variable is non-@code{nil}, Emacs makes backups by copying in cases
-where renaming would change either the owner or the group of the file.
+If this variable is non-@code{nil} (the default), Emacs makes backups
+by copying in cases where renaming would change either the owner or
+the group of the file.
The value has no effect when renaming would not alter the owner or
group of the file; that is, for files which are owned by the user and
@deffn Command auto-save-mode arg
When used interactively without an argument, this command is a toggle
-switch: it turns on auto-saving of the current buffer if it is off, and
-vice versa. With an argument @var{arg}, the command turns auto-saving
-on if the value of @var{arg} is @code{t}, a nonempty list, or a positive
-integer. Otherwise, it turns auto-saving off.
+switch: it turns on auto-saving of the current buffer if it is off,
+and vice versa. When called from Lisp with no argument, it turns
+auto-saving on. With an argument @var{arg}, it turns auto-saving on
+if the value of @var{arg} is @code{t}, a nonempty list, or a positive
+integer; otherwise, it turns auto-saving off.
@end deffn
@defun auto-save-file-name-p filename
the buffer. Preserving any additional markers would be problematical.
@end deffn
+@defvar revert-buffer-in-progress-p
+@code{revert-buffer} binds this variable to a non-@code{nil} value
+while it is working.
+@end defvar
+
You can customize how @code{revert-buffer} does its work by setting
the variables described in the rest of this section.
the modified contents---but only if @code{revert-buffer-function} is
@code{nil}.
@end defvar
+
+@c FIXME? Move this section from arevert-xtra to here?
+@defvar buffer-stale-function
+The value of this variable, if non-@code{nil}, specifies a function
+to call to check whether a non-file buffer needs reverting
+@iftex
+(@pxref{Supporting additional buffers,,, emacs-xtra, Specialized Emacs Features}).
+@end iftex
+@ifnottex
+(@pxref{Supporting additional buffers,,, emacs}).
+@end ifnottex
+@end defvar
+