+Note that you should only use this option on source files that are quiescent.
+If you are using this to move files that show up in a particular directory over
+to another host, make sure that the finished files get renamed into the source
+directory, not directly written into it, so that rsync can't possibly transfer
+a file that is not yet fully written. If you can't first write the files into
+a different directory, you should use a naming idiom that lets rsync avoid
+transferring files that are not yet finished (e.g. name the file "foo.new" when
+it is written, rename it to "foo" when it is done, and then use the option
+bf(--exclude='*.new') for the rsync transfer).
+
+Starting with 3.1.0, rsync will skip the sender-side removal (and output an
+error) if the file's size or modify time has not stayed unchanged.
+