Haskell向socket客户端发送All消息的结果是。`Exception: Network.Socket.sendBuf: invalid argument (Transport endpoint is not connected)`。

Question

我遇到的错误是 *** Exception: Network.Socket.sendBuf: invalid argument (Transport endpoint is not connected) 呼叫 Network.Socket.ByteString.sendAll (黑客文档 - sendall)从套接字服务器发送至套接字客户端。

我不知道为什么会出现这个错误？似乎我只能以一种方式发送数据？

当使用netcat而不是Haskell客户端时，我也遇到了同样的错误。

echo 'test' | nc  -N -U /tmp2/test2.soc

---

客户端输出：

*Server Main> main
Hello, Haskell!2
"sent ping....."

来自服务器的输出：

*Server> serv
"begin"
"Running daemon"
"begin2"
<socket: 13>

"Got message:"
"ping"
"Sending pong...."
*** Exception: Network.Socket.sendBuf: invalid argument (Transport endpoint is not connected)

---

完成项目。https:/github.comchrissoundUnixSocketPingPongHaskellTest。

完整的源码。

客户端：

{-# Language OverloadedStrings #-}
module Main where

import Network.Socket hiding (send)
import Network.Socket.ByteString as NBS
import Control.Concurrent
import Control.Monad

main :: IO ()
main = do
  putStrLn "Hello, Haskell!2"
  withSocketsDo $ do
    soc <- socket AF_UNIX Stream 0
    connect (soc) (SockAddrUnix "/tmp2/test2.soc")
    forever $ do
      send soc ("ping")
      threadDelay $ 1 * 10^6
      print "sent ping....."
      threadDelay $ 1 * 10^6
      msg <- NBS.recv soc 400000
      print msg
      print "got reply to ping...."
    close soc

服务器：

{-# Language OverloadedStrings #-}
module Server where

import Network.Socket hiding (send)
import Network.Socket.ByteString as NBS
import Control.Concurrent
import Control.Monad

serv :: IO ()
serv = do
  print "begin"
  print "Running daemon"
  soc <- socket AF_UNIX Stream 0
  bind soc . SockAddrUnix $ "/tmp2/test2.soc"
  listen soc maxListenQueue
  accept soc >>= (\(x,y)-> do
    print "begin2"
    print x
    print y
    forever $ do
      msg <- NBS.recv x 400000
      print "Sending pong...."
      NBS.sendAll soc "ppong"
      print "alll done"

      threadDelay $ 3 * 10^6
      )

Answer 1

你是在监听套接字上发送的；你可能想在接受的套接字上发送。

  listen soc maxListenQueue
  accept soc >>= (\(x,y)-> do
    ...
    NBS.sendAll soc "ppong"  -- should be   sendAll x "ppong"