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diff --git a/XMonad/Util/StringProp.hs b/XMonad/Util/StringProp.hs
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+-----------------------------------------------------------------------------
+-- |
+-- Module      :  XMonad.Util.StringProp
+-- Copyright   :  (c) Nicolas Pouillard 2009
+-- License     :  BSD-style (see LICENSE)
+--
+-- Maintainer  :  Nicolas Pouillard <nicolas.pouillard@gmail.com>
+-- Stability   :  unstable
+-- Portability :  unportable
+--
+-- Internal utility functions for storing Strings with the root window.
+--
+-- Used for global state like IORefs with string keys, but more latency,
+-- persistent between xmonad restarts.
+
+module XMonad.Util.StringProp (
+    StringProp,
+    getStringProp, setStringProp,
+    getStringListProp, setStringListProp,
+    ) where
+
+import XMonad
+import Control.Monad(liftM)
+import Control.Applicative((<$>))
+import Foreign.C.String (castCCharToChar,castCharToCChar)
+
+type StringProp = String
+
+withStringProp :: (MonadIO m) => StringProp -> Display -> (Window -> Atom -> m b) -> m b
+withStringProp prop dpy f = do
+    rootw <- io $ rootWindow dpy $ defaultScreen dpy
+    a     <- io $ internAtom dpy prop False
+    f rootw a
+
+-- | Set the value of a string property.
+setStringProp :: (MonadIO m) => Display -> StringProp -> [Char] -> m ()
+setStringProp dpy prop string =
+  withStringProp prop dpy $ \rootw a ->
+    io $ changeProperty8 dpy rootw a a propModeReplace $ map castCharToCChar string
+
+-- | Get the name of a string property and returns it as a 'Maybe'.
+getStringProp :: (MonadIO m) => Display -> StringProp -> m (Maybe [Char])
+getStringProp dpy prop =
+  withStringProp prop dpy $ \rootw a -> do
+    p <- io $ getWindowProperty8 dpy a rootw
+    return $ map castCCharToChar <$> p
+
+-- | Given a property name, returns its contents as a list. It uses the empty
+-- list as default value.
+getStringListProp :: (MonadIO m) => Display -> StringProp -> m [String]
+getStringListProp dpy prop = maybe [] words `liftM` getStringProp dpy prop
+
+-- | Given a property name and a list, sets the value of this property with
+-- the list given as argument.
+setStringListProp :: (MonadIO m) => Display -> StringProp -> [String] -> m ()
+setStringListProp dpy prop str = setStringProp dpy prop (unwords str)