Lars> Emacs has temporary-file-directory, which defaults to "/tmp/". It's a Lars> nice variable to have, since all other temp dir variables can use that Lars> variable as the default value, so I think XEmacs should have it as well. Seems reasonable. Here's the trivial untested patch: 1998-12-21 Martin Buchholz <martin(a)xemacs.org&gt; * files.el (temporary-file-directory): Add new variable, compatible with FSF Emacs 20.3 --- etc/NEWS.old +++ etc/NEWS ＠＠ -121,6 +121,11 ＠＠ An extra bonus is that checking for circularities is not just friendlier, but actually faster than checking for quit. +** The new variable temporary-file-directory specifies the directory +to use for creating temporary files. The default value is determined +in a reasonable way for your operating system; on Unix systems it is +based on the TMP and TMPDIR environment variables. +  * Changes in XEmacs 21.0 ======================== --- lisp/files.el.old +++ lisp/files.el ＠＠ -354,6 +354,14 ＠＠ (defalias 'lock-buffer 'ignore)) (or (fboundp 'unlock-buffer) (defalias 'unlock-buffer 'ignore)) + +(defvar temporary-file-directory + (file-name-as-directory + (if (memq system-type '(ms-dos windows-nt)) + (or (getenv "TEMP") (getenv "TMPDIR") (getenv "TMP") "c:/temp") + (or (getenv "TMPDIR") (getenv "TMP") (getenv "TEMP") "/tmp"))) + "The directory for writing temporary files.") +  ;;FSFmacs bastardized ange-ftp cruft ;; This hook function provides support for ange-ftp host name

You probably meant this rhetorically, but I'll answer it anyway, since it is a FAQ. Jonathan Harris writes: Because they are different programs maintained by different people with different priorities and different work schedules. We would block their work and they would block ours if we try too hard to stay in synch. Cross-compatibility is overrated anyway. In my applications, I have to use interface functions for most new things introduced in XEmacs, not just because FSF Emacs doesn't have them, but because older versions of XEmacs don't have them either. So FSF Emacs is just another clause in a conditional that has to exist anyway.