qwurx [shmem] ~/tmp/diff> diff -ur test1 test2
diff -ur test1/common/common.txt test2/common/common.txt
--- test1/common/common.txt	2017-03-09 12:28:15.215474776 +0100
+++ test2/common/common.txt	2017-03-09 12:28:38.639837796 +0100
@@ -1 +1 @@
-This is a common line
+This is a common line.
Only in test2/common: common.txt~
Only in test1: different1
Only in test2: different2