--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libgo/mvifdiff.sh	Fri Oct 27 22:46:09 2017 +0900
@@ -0,0 +1,15 @@
+#!/bin/sh
+
+# Copyright 2014 The Go Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style
+# license that can be found in the LICENSE file.
+
+# The mvifdiff.sh script works like the mv(1) command, except
+# that it does not touch the destination file if its contents
+# are the same as the source file.
+
+if cmp -s "$1" "$2" ; then
+  rm "$1"
+else
+  mv "$1" "$2"
+fi