Benjamin Edwards <
edwards.benj@gmail.com> wrote:
> I am looking to make a simple program that polls an interface once a
> second or so. I thought I could use threadDelay for this, so knocked
> up the following toy program to test my idea.
>
> module TD
> where
>
> import Control.Concurrent
> import Control.Concurrent.MVar
>
> main :: IO ()
> main = do mv <- newEmptyMVar
> forkIO $ loop mv 0 "Hai"
> takeMVar mv
> return ()
> where loop mv n msg = do putStrLn msg
> threadDelay 10000
> if n < 10 then loop mv (n+1) msg
> else putMVar mv ()
>
> It doesn't work, in as much as I see all the messages printed
> seemingly as fast as Std out will print them. What am I doing wrong?