Permissions of auto-save files (Re: permissions of dribble file)

[Carsten Bormann <cabo@Informatik.Uni-Bremen.DE>]

John Palmieri writes:
> Here is an excerpt from the gnus info files (node: Auto Save):
> 
> > The dribble file will get the same file
> > permissions as the `.newsrc' file.
> 
> Here is an excerpt from my directory:
> 
>   /bb/palmieri:
>   total 164
>   -rw-------  1 palmieri     3729 Dec 18 14:01 .newsrc
>   -rw-------  1 palmieri    18885 Mar 13 12:02 .newsrc.eld
> 
> Here is my dribble file:
> 
>   -rw-r--r--  1 palmieri       84 Mar 13 12:05 #.newsrc-dribble#

No -- that's not your dribble file, its the auto-save file of a
not-yet-existing dribble file.

Each time we install a new version of Emacs here, we apply the
following patch (oops, this patch is reversed -- the default mode is
changed from 0666 to 0600 by the patch):

cd /home/rn-src/emacs-19.34/src/
gdiff -u /home/rn-src/emacs-19.34/src/fileio.c /home/rn-src/emacs-19.34/src/fileio.c.orig
--- /home/rn-src/emacs-19.34/src/fileio.c	Mon Sep  9 18:13:36 1996
+++ /home/rn-src/emacs-19.34/src/fileio.c.orig	Sat Jul 20 09:00:27 1996
@@ -3997,7 +3997,7 @@
     /* But make sure we can overwrite it later!  */
     auto_save_mode_bits = st.st_mode | 0600;
   else
-    auto_save_mode_bits = 0600;
+    auto_save_mode_bits = 0666;
 
   return
     Fwrite_region (Qnil, Qnil,

Diff finished at Thu Mar 13 18:23:40

This gross hack is intended to make auto-save files for buffers like
*mail* more secure -- it might help with your problem.  It also causes
auto-save files that you may want to keep accessible to be unreadable
for your colleagues.  Sigh.

Of course, Gnus could save an empty dribble file at the outset, making
this hack unnecessary *just for dribble files*.  My taste buds don't
know whether this would be less gross.

The real thing would be a way to indicate, from Emacs-Lisp, the
desired privacy mode for auto-save files for each buffer in Emacs
separately -- even those that don't have files yet (that's why I put
bug-gnu-emacs into the CC).

Gruesse, Carsten