On Sun, Nov 02, 2008 at 09:15:25PM +0100, Marc Weber wrote:
On Mon, Nov 03, 2008 at 01:02:12AM +1100, Rafal Kolanski wrote:
Rafal Kolanski. -- Pass text to md5sum and drop the final " -" when returning hashMD5 text = do (inp,out,err,pid) <- runInteractiveProcess "md5sum" [] Nothing Nothing forkIO $ do hPutStrLn inp text hClose inp exit <- waitForProcess pid case exit of ExitFailure _ -> error "md5sum fail" _ -> return () [...]
Why do you use forkIO here? It's not necessary. The process will run in background on its own. ?
It looks to me like this code requires a forkIO, not in the writing to inp, but rather in the reading of out and err. Otherwise, those buffers may fill up and your process will hang... -- David Roundy http://www.darcs.net