lib/common/user_interface.rb: add --help to the usage info

diff --git a/lib/common/user_interface.rb b/lib/common/user_interface.rb
index 1bcf67ead3f7f37101e693092ed4d049924b7632..92ed74b9937e25a146d5e1a4133d78c704bf97ca 100644 (file)
--- a/lib/common/user_interface.rb
+++ b/lib/common/user_interface.rb
@@ -12,7 +12,7 @@ class UserInterface
   #   invocation.
   #
   def self.usage(program_name)
-    return "#{program_name} [prune | rm <target> | mv <src> <dst>]"
+    return "#{program_name} [--help] [prune | rm <target> | mv <src> <dst>]"
   end