In this program, the HGL window only updates when I mouseover it. Can someone tell me why this is / how I should avoid it? Thanks! Rodrigo module Main where import Graphics.HGL import Control.Concurrent import Control.Concurrent.MVar import Control.Monad main = do stringMVar <- newEmptyMVar forkIO . runGraphics $ do w <- openWindowEx "HGLTest" Nothing (300, 100) DoubleBuffered Nothing forever $ do string <- takeMVar stringMVar setGraphic w $ text (0, 0) string forever $ do string <- getLine putMVar stringMVar string