(ediff-test-patch-utility): Catch error and return nil.

diff --git a/lisp/ediff-ptch.el b/lisp/ediff-ptch.el
index 0b6bc49e2903eef9070f40ae46292a2cf6f90081..29174ff8e97e7744845ac21cda25e9c997a1a9ac 100644 (file)
--- a/lisp/ediff-ptch.el
+++ b/lisp/ediff-ptch.el
@@ -85,12 +85,14 @@ See also `ediff-backup-specs'."
   :group 'ediff-ptch)
 
 (defun ediff-test-patch-utility ()
-  (cond ((zerop (call-process ediff-patch-program nil nil nil "-z." "-b"))
-        ;; GNU `patch' v. >= 2.2
-        'gnu)
-       ((zerop (call-process ediff-patch-program nil nil nil "-b"))
-        'posix)
-       (t 'traditional)))
+  (condition-case nil
+      (cond ((zerop (call-process ediff-patch-program nil nil nil "-z." "-b"))
+            ;; GNU `patch' v. >= 2.2
+            'gnu)
+           ((zerop (call-process ediff-patch-program nil nil nil "-b"))
+            'posix)
+           (t 'traditional))
+    (file-error nil)))
 
 (defcustom ediff-backup-specs 
   (let ((type (ediff-test-patch-utility)))