Add directory hierarchy copying example.

usr.bin/tar/bsdtar.1

@@ -457,6 +457,13 @@ To extract all entries from the archive on
 the default tape drive:
 .Dl Nm Fl x
 .Pp
+To move file hierarchies, invoke
+.Nm
+as
+.Dl Nm Fl cf Pa - Fl C Pa srcdir\ . | Nm Fl xpBf Pa - Fl C Pa destdir
+or more traditionally
+.Dl cd srcdir \; Nm Fl cf Pa -\ . | ( cd destdir \; Nm Fl xpBf Pa - )
+.Pp
 In create mode, the list of files and directories to be archived
 can also include directory change instructions of the form
 .Cm -C Ns Pa foo/baz