Network problem with ghc on WinXP

[robin abraham]

Works like a charm now :)
Thank you for the insight.
Robin.

>Hi there,
>
>looks like a network byte-order vs host byte-order gotcha.
>Never use the PortNum constructor, but declare 'portnum'
>to have type PortNumber and simply drop the use of PortNum
>in your code alltogether. Alternatively, use intToPortNumber
>to translate between Int and PortNumber.
>
>hth
>--sigbjorn
>
>----- Original Message ----- 
>From: "robin abraham" <abraharo at cs.orst.edu>
>To: <glasgow-haskell-users at haskell.org>
>Sent: Wednesday, January 28, 2004 21:57
>Subject: Network problem with ghc on WinXP
>
>
>> Hi,
>>
>> I have ghc-6.0.1 on WinXP and Solaris. I have a simple echo server
>(server.hs
>> given below) and client (client.hs given below) and I encounter the
>following:
>> 1) server.hs compiled and running on Solaris:
>>    a) client.hs (Solaris) can connect.
>>    b) client.hs (WinXP) cannot connect.
>>    c) telnet (WinXP) can connect.
>>    d) telnet (Solaris) can connect.
>>    e) Scan of port 3000 shows server is listening.
>>
>> 2) server.hs compiled and running on WinXP:
>>    a) client.hs (Solaris) cannot connect.
>>    b) client.hs (WinXP) can connect.
>>    c) telnet (WinXP) cannot connect.
>>    d) telnet (Solaris) cannot connect.
>>    e) Scan of ports does not show server.
>>
>> Basically, when the server is running on WinXP, only the Haskell program
>> client.hs (also running on the same WinXP machine) can "converse" with it
>> through the socket connection. To verify this, I wrote a client in C# -
>from the
>> WinXP machine, it can connect to server running on my Solaris machine but
>not to
>> server on the same WinXP machine.
>>
>> Why isn't the server program on WinXP not behaving itself? Any
>help/guidance
>> would be highly appreciated.
>>
>> Thank you.
>> Robin.
>>
>> -- server.hs
>> module Main where
>>
>> import SocketPrim
>> import Concurrent
>> import System (getArgs,exitFailure)
>> import Exception(finally)
>> import MVar
>> import IO
>>
>> server_sock :: IO (Socket)
>> server_sock = do
>>     s <- socket AF_INET Stream 6
>>     setSocketOption s ReuseAddr 1
>>     bindSocket s (SockAddrInet (PortNum portnum) iNADDR_ANY)
>>     listen s 2
>>     return s
>>
>> echo_server :: Socket -> IO ()
>> echo_server s = do
>>     (s', clientAddr) <- accept s
>>     h <- socketToHandle s' ReadWriteMode
>>     proc <- read_data s' 0
>>     putStrLn ("server processed "++(show proc)++" bytes")
>>     sClose s'
>>     where
>>         read_data sock totalbytes = do
>>             str <- recv sock 18
>>             putStrLn ("Server recv: " ++ str)
>>             if ((length str) >= 18)
>>                 then do
>>                     putStrLn ("Server read: " ++ str)
>>                     writ <- send sock str
>>                     putStrLn ("Server wrote: " ++ str)
>>                     read_data sock $! (totalbytes+(length $! str))
>>                 else do
>>                     putStrLn ("server read: " ++ str)
>>                     return totalbytes
>>
>> message     = "Hello there sailor"
>> portnum     = 3000
>>
>> main = withSocketsDo $ do {
>>     ~[n] <- getArgs;
>>     ssock <- server_sock;
>>     s <- myForkIO (echo_server ssock);
>>     join s;
>>     putStrLn "join s";
>>     }
>>
>> myForkIO :: IO () -> IO (MVar ())
>> myForkIO io = do
>>     mvar <- newEmptyMVar
>>     forkIO (io `finally` putMVar mvar ())
>>     return mvar
>>
>> join :: MVar () -> IO ()
>> join mvar = readMVar mvar
>>
>> -- end of server.hs
>>
>> -- ***********************************************
>>
>> -- client.hs
>>
>> module Main where
>>
>> import SocketPrim
>> import Concurrent
>> import System (getArgs,exitFailure)
>> import Exception(finally)
>> import MVar
>> import IO
>>
>> local       = "128.193.39.108"
>> message     = "Hello there sailor"
>> portnum     = 3000
>>
>> client_sock = do
>>     s <- socket AF_INET Stream 6
>>     ia <- inet_addr local
>>     connect s (SockAddrInet (PortNum portnum) ia)
>>     return s
>>
>> echo_client n = do
>>     s <- client_sock
>>     drop <- server_echo s n
>>     sClose s
>>     where
>>         server_echo sock n = if n > 0
>>             then do
>>                 send sock message
>>                 putStrLn ("Client wrote: " ++ message)
>>                 str <- recv sock 19
>>                 if (str /= message)
>>                     then do
>>                         putStrLn ("Client read error: " ++ str)
>>                         exitFailure
>>                     else do
>>                         putStrLn ("Client read success")
>>                         server_echo sock (n-1)
>>             else do
>>                 putStrLn "Client read nil"
>>                 return []
>>
>> main = withSocketsDo $ do
>>     ~[n] <- getArgs
>>     c <- myForkIO (echo_client (read n::Int))
>>     join c
>>     putStrLn "join c"
>>
>> myForkIO :: IO () -> IO (MVar ())
>> myForkIO io = do
>>     mvar <- newEmptyMVar
>>     forkIO (io `finally` putMVar mvar ())
>>     return mvar
>>
>> join :: MVar () -> IO ()
>> join mvar = readMVar mvar
>>
>> -- end of client.hs
>>