Accept new `always' value for option `buffer-offer-save'

Also revert ee512e9a82

* lisp/files.el (buffer-offer-save): In addition to nil and t, now
  allows a third symbol value, `always'. A buffer where this option is
  set to `always' will always be offered for save by
  `save-some-buffers'.
  (save-some-buffers): Check the exact value of this buffer-local
  variable. No longer check the buffer name, or the value of
  `write-contents-functions'.
* doc/lispref/buffers.texi (Killing Buffers): Note change in manual.
* doc/lispref/files.texi (Saving Buffers): Remove note about buffer
  names.
* etc/NEWS: Mention in NEWS.

2 files changed, 10 insertions, 8 deletions

diff --git a/doc/lispref/buffers.texi b/doc/lispref/buffers.texi
index cf24a730ba6..0d02cb3d3e9 100644
--- a/doc/lispref/buffers.texi
+++ b/doc/lispref/buffers.texi
@@ -1089,12 +1089,15 @@ is not cleared by changing major modes.
 
 @defopt buffer-offer-save
 This variable, if non-@code{nil} in a particular buffer, tells
-@code{save-buffers-kill-emacs} and @code{save-some-buffers} (if the
-second optional argument to that function is @code{t}) to offer to
-save that buffer, just as they offer to save file-visiting buffers.
-@xref{Definition of save-some-buffers}.  The variable
-@code{buffer-offer-save} automatically becomes buffer-local when set
-for any reason.  @xref{Buffer-Local Variables}.
+@code{save-buffers-kill-emacs} to offer to save that buffer, just as
+it offers to save file-visiting buffers.  If @code{save-some-buffers}
+is called with the second optional argument set to @code{t}, it will
+also offer to save the buffer.  Lastly, if this variable is set to the
+symbol @code{always}, both @code{save-buffers-kill-emacs} and
+@code{save-some-buffers} will always offer to save.  @xref{Definition
+of save-some-buffers}.  The variable @code{buffer-offer-save}
+automatically becomes buffer-local when set for any reason.
+@xref{Buffer-Local Variables}.
 @end defopt
 
 @defvar buffer-save-without-query
diff --git a/doc/lispref/files.texi b/doc/lispref/files.texi
index b1b858a6b4b..f49b02de97c 100644
--- a/doc/lispref/files.texi
+++ b/doc/lispref/files.texi
@@ -368,8 +368,7 @@ With an argument of 0, unconditionally do @emph{not} make any backup file.
 This command saves some modified file-visiting buffers.  Normally it
 asks the user about each buffer.  But if @var{save-silently-p} is
 non-@code{nil}, it saves all the file-visiting buffers without
-querying the user.  Additionally, buffers whose name begins with a
-space (``internal'' buffers) will not be offered for save.
+querying the user.
 
 @vindex save-some-buffers-default-predicate
 The optional @var{pred} argument provides a predicate that controls