From: Michael Albinus <michael.albinus@gmx.de>
Date: Tue, 25 Aug 2009 08:45:41 +0000 (+0000)
Subject: * simple.el (process-file-side-effects): New defvar.
X-Git-Tag: emacs-pretest-23.1.90~1697
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=2c4f2562bbb383a64b6f703cc280ea6a29ed0d23;p=emacs.git

* simple.el (process-file-side-effects): New defvar.
---

diff --git a/lisp/simple.el b/lisp/simple.el
index c8e537cdf50..7349f4d0617 100644
--- a/lisp/simple.el
+++ b/lisp/simple.el
@@ -2513,6 +2513,17 @@ value passed."
       (when stderr-file (delete-file stderr-file))
       (when lc (delete-file lc)))))
 
+(defvar process-file-side-effects t
+  "Whether a call of `process-file' changes remote files.
+
+Per default, this variable is always set to `t', meaning that a
+call of `process-file' could potentially change any file on a
+remote host.  When set to `nil', a file handler could optimize
+its behaviour with respect to remote file attributes caching.
+
+This variable should never be changed by `setq'.  Instead of, it
+shall be set only by let-binding.")
+
 (defun start-file-process (name buffer program &rest program-args)
   "Start a program in a subprocess.  Return the process object for it.