Re: Viewing HTML-mails with external browsers - proposed code

[Katsumi Yamaoka <yamaoka@jpl.org>]

>>>>> In <b4m3bimer4f.fsf@jpl.org> Katsumi Yamaoka wrote:

> I'll add the Emacs 22 version of make-temp-file.

I've added it to the trunk and made it work with XEmacs as well.
However, it is a bit unsafe with XEmacs.  It is thought that a
sly attacker can make a temp file (which can be read by him) of
the same name just before a user makes it.  Therefore, XEmacs
users had better set a secure temp directory which only you can
access.

#v+
`temp-directory' is a built-in function
(temp-directory)

Documentation:
Return the pathname to the directory to use for temporary files.
On MS Windows, this is obtained from the TEMP or TMP environment
variables, defaulting to / if they are both undefined.
On Unix it is obtained from TMPDIR, with /tmp as the default.
#v-

The former one was rather unsafe if a user doesn't use a secure
temp directory, though.  In addition, the way that
`mm-display-external' used (i.e., `rename-file' after
`mm-make-temp-file') was also a bit unsafe for the same reason.

The function can be modified so that it may work also with Emacs
20, but it will be a bit unsafe as well as XEmacs.

P.S.  APEL provides a pretty good version of `make-temp-file'.
If you load `poe' before `mm-util', `mm-make-temp-file' will be
an alias to it.  I think the one defined in mm-util.el is
sufficient, though.