bug#8047: 23.2.94; Auto image mode breaks C-x C-w

[Eli Zaretskii]

 emacs -Q
 C-x C-f FOO.png RET  (or any other image file)
 C-x C-w BAR.png RET

   => save-buffer: Text is read-only

This happens because image-file.el makes the whole buffer displaying
the image read-only.

I think this nuisance should be fixed before Emacs 23.3 is released.


In GNU Emacs 23.2.94.1 (i386-mingw-nt5.1.2600)
 of 2011-02-15 on HOME-C4E4A596F7
Windowing system distributor `Microsoft Corp.', version 5.1.2600
configured using `configure --with-gcc (3.4)'

Important settings:
  value of $LC_ALL: nil
  value of $LC_COLLATE: nil
  value of $LC_CTYPE: nil
  value of $LC_MESSAGES: nil
  value of $LC_MONETARY: nil
  value of $LC_NUMERIC: nil
  value of $LC_TIME: nil
  value of $LANG: ENU
  value of $XMODIFIERS: nil
  locale-coding-system: cp1255
  default enable-multibyte-characters: t

Major mode: RMAIL

Minor modes in effect:
  diff-auto-refine-mode: t
  desktop-save-mode: t
  show-paren-mode: t
  display-time-mode: t
  tooltip-mode: t
  mouse-wheel-mode: t
  tool-bar-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  blink-cursor-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  temp-buffer-resize-mode: t
  line-number-mode: t

Recent input:
C-x b I N B <tab> - <tab> <return> <C-next> <C-next> 
<C-next> <C-next> <C-next> <C-next> <C-next> <C-next> 
<M-end> C-x 5 b * i <tab> 1 > <return> <help-echo> 
<switch-frame> C-x 5 b x d <tab> <return> <switch-frame> 
C-x b <return> C-x C-f i m a g e - f i <tab> <return> 
<next> <next> <next> <next> C-z C-z C-z C-z C-z C-z 
C-z C-z C-z C-z C-z C-z C-z C-z C-z C-z C-z C-z C-z 
C-z C-z C-z C-z C-z C-z C-z C-z C-z C-z C-z C-z C-z 
C-z C-z C-z C-z C-z C-z C-z C-z C-z C-z C-z C-z C-z 
C-z C-z C-z C-z C-z C-z C-z C-z C-z C-z C-z C-z C-z 
C-z C-z C-z C-z C-z C-z C-z C-z C-z C-z C-z C-z C-z 
C-z C-z C-z C-z C-z C-z C-z C-z C-z C-z C-z C-z C-z 
C-z C-z C-z C-z C-z C-z <prior> <prior> <prior> <prior> 
<prior> <prior> <prior> <next> <next> <next> <next> 
<next> <up> <prior> <next> <next> <next> <prior> <prior> 
C-x b I N B <tab> <return> C-x C-f <M-backspace> d 
a t a / e m a c s - m e n <tab> <return> C-x C-w x 
x . p n g <return> C-x k <return> y e s <return> M-x 
r e p o r t - e m <tab> <return>

Recent messages:
Indentation setup for shell type sh
Setting up indent for shell type sh
setting up indent stuff
Indentation variables are now local.
Indentation setup for shell type sh
Note: file is write protected [3 times]
Wrote d:/usr/eli/.emacs.desktop.lock
Desktop: 260 buffers restored.
Type C-c C-c to view the image as text.
Saving file d:/usr/eli/data/xx.png...
save-buffer: Text is read-only

Load-path shadows:
None found.

Features:
(shadow mailalias sendmail emacsbug image-mode ld-script sh-script
executable dired-x dired-aux dired tcl nxml-uchnm rng-xsd xsd-regexp
rng-cmpct rng-nxml rng-valid rng-loc rng-uri rng-parse nxml-parse
rng-match rng-dt rng-util rng-pttrn nxml-ns nxml-mode nxml-outln
nxml-rap nxml-util nxml-glyph nxml-enc xmltok sgml-mode arc-mode
archive-mode parse-time conf-mode newcomment tar-mode add-log generic
vc-cvs diff-mode jka-compr texinfo org-wl org-w3m org-vm org-rmail
org-mhe org-mew org-irc org-jsinfo org-infojs org-html org-exp
org-exp-blocks org-agenda org-info org-gnus org-bibtex org-bbdb org
byte-opt warnings bytecomp byte-compile advice help-fns advice-preload
org-footnote org-src org-list org-faces org-compat org-macs make-mode
gud comint ring flyspell ispell noutline outline easy-mmode autorevert
info vc-bzr cc-mode cc-fonts cc-menus cc-cmds cc-styles cc-align
cc-engine cc-vars cc-defs regexp-opt rmailsum rmailmm message
ecomplete rfc822 mml easymenu mml-sec password-cache mm-decode
mm-bodies mm-encode mailcap mailabbrev nnheader gnus-util netrc
gmm-utils wid-edit mailheader canlock sha1 hex-util hashcash
mail-parse rfc2231 rmail rfc2047 rfc2045 ietf-drums time-date qp
mm-util mail-prsvr mail-utils desktop server filecache saveplace
generic-x paren battery time tooltip ediff-hook vc-hooks
lisp-float-type mwheel dos-w32 disp-table ls-lisp w32-win w32-vars
tool-bar dnd fontset image fringe lisp-mode register page menu-bar
rfn-eshadow timer select scroll-bar mldrag mouse jit-lock font-lock
syntax facemenu font-core frame cham georgian utf-8-lang misc-lang
vietnamese tibetan thai tai-viet lao korean japanese hebrew greek
romanian slovak czech european ethiopic indian cyrillic chinese
case-table epa-hook jka-cmpr-hook help simple abbrev loaddefs button
minibuffer faces cus-face files text-properties overlay md5 base64
format env code-pages mule custom widget hashtable-print-readable
backquote make-network-process multi-tty emacs)