Hi, Is is possible to get Network.Socket.ByteString.recv to be non-blocking (i.e. return directly even if no data is available) ? I have tried ti use setSocketOption sock NoDelay 1 but then I get the following error: setSocketOption: unsupported operation (Protocol not available) Here is the code if it may help (I'm on linux btw). sock <- socket AF_INET Datagram 17 -- 17 is IPPROTO_UDP addr <- inet_addr "127.0.0.1" bindSocket sock (SockAddrInet 44004 addr) setSocketOption sock NoDelay 1 -- <-- doesn't seem to work addr <- inet_addr "127.0.0.1" forever $ do sent <- sendTo sock "hello" (SockAddrInet 44005 addr) dat <- recv sock 5 -- <-- I'd like it to be non-blocking B.putStrLn dat threadDelay 1000000 -- 1 second Thanks, Thu