$ diff -ruN tmp.empty tmp.full
diff -ruN tmp.empty/1 tmp.full/1
--- tmp.empty/1 1969-12-31 16:00:00.000000000 -0800
+++ tmp.full/1  2011-06-23 02:46:59.875000000 -0700
@@ -0,0 +1 @@
+ECHO is on.
diff -ruN tmp.empty/2 tmp.full/2
--- tmp.empty/2 1969-12-31 16:00:00.000000000 -0800
+++ tmp.full/2  2011-06-23 02:47:01.312500000 -0700
@@ -0,0 +1 @@
+ECHO is on.