Don't touch subdirs.el if it is unchanged.

2 files changed, 8 insertions, 0 deletions

diff --git a/ChangeLog b/ChangeLog
index 0a12b3d4e5b..50bfa20065a 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+2008-05-28  Stefan Monnier  <monnier@iro.umontreal.ca>
+
+        * update-subdirs: Don't touch subdirs.el if it is unchanged.
+
 2008-05-14  Kenichi Handa  <handa@m17n.org>
 
         * configure: Regenerate.
diff --git a/update-subdirs b/update-subdirs
index d7e7012dadc..b4df2cea045 100755
--- a/update-subdirs
+++ b/update-subdirs
@@ -45,7 +45,11 @@ else
 ;; version-control: never
 ;; no-byte-compile: t
 ;; End:" > subdirs.el~
+  if cmp "subdirs.el" "subdirs.el~" >/dev/null 2>&1; then
+    :; # echo "subdirs.el unchanged";
+  else
   mv subdirs.el~ subdirs.el
+  fi
 fi
 
 # arch-tag: 56ebcf1b-5c30-4934-b0b4-72d374064704