Re: [Haskell-cafe] getChar + System.Cmd.system + threads causes hangups

Here is a version that works fine: myRawSystem cmd args = do (inP, outP, errP, pid) <- runInteractiveProcess cmd args Nothing Nothing hClose inP os <- pGetContents outP es <- pGetContents errP ec <- waitForProcess pid case ec of ExitSuccess -> return () ExitFailure e -> do hPutStrLn stderr ("Running process "++unwords (cmd:args)++" FAILED ("++show e++")") hPutStrLn stderr os hPutStrLn stderr es hPutStrLn stderr ("Raising error...") fail "Running external command failed" pGetContents h = do mv <- newEmptyMVar let put [] = putMVar mv [] put xs = last xs `seq` putMVar mv xs forkIO (hGetContents h >>= put) takeMVar mv