Error text-read-only in shell-command

[Tassilo Horn <tassilo@member.fsf.org>]

Hi all,

I've just dired and opened acroread using & on a pdf file to fill out
some forms.  After closing that, I wanted to open another file with an
external app using &.  But then I got an text-read-only error.

I've tracked it down to the call to `erase-buffer' in `shell-command'.
That fails, because although buffer-read-only is set to nil explicitly,
parts of the output acroread produced in *Async Shell Command Output*
has the read-only text property set to 'fence (whatever that means).
(The linebreaks have that property...)

The following patch fixes the issue.  Ok to commit?

--8<---------------cut here---------------start------------->8---
=== modified file 'lisp/simple.el'
--- lisp/simple.el	2011-01-02 20:28:40 +0000
+++ lisp/simple.el	2011-01-12 08:53:08 +0000
@@ -2341,7 +2341,10 @@
 		      (error "Shell command in progress")))
 		(with-current-buffer buffer
 		  (setq buffer-read-only nil)
-		  (erase-buffer)
+		  ;; Setting buffer-read-only to nil doesn't help for
+		  ;; characters with read-only text property.
+		  (let ((inhibit-read-only t))
+		    (erase-buffer))
 		  (display-buffer buffer)
 		  (setq default-directory directory)
 		  (setq proc (start-process "Shell" buffer shell-file-name
--8<---------------cut here---------------end--------------->8---

Bye,
Tassilo