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Manage vins6 VB6: close the connection and connect to another server

I am working on an old VB6 application. The application uses the RAS API to establish a modem connection, and then uses the winsock control to connect to the IP address and port.

Now I am adding a failover function for this application, where if it cannot connect to the server, it tries to connect to the next one in the list.

Let's say I have two servers: server application A and server application B. (During my tests, I exchanged them to make sure both servers are accessible and there is no routing / firewall problem.)

If I stop server application A, then something rather strange will happen when the application tries to connect to server application A, and then to server application B:

mySocket.close
mySocket.Connect serverA, portA
  • mySocket.state = 6 sckConnecting
  • The connect socket event is called
  • mySocket.state = 7 sckConnected
  • mySocket.state = 8 sckClosing

(which seems a little odd: I'm not sure why it seems to connect for a few moments.)

The socket remains in sckClosing state. After a few hundred milliseconds, I will move on to trying to connect to server B:

mySocket.close
  • mySocket.state = 0 sckClosed

.

mySocket.Connect serverB, portB
  • mySocket.state = 6 sckConnecting Socket Error Event
  • called with error 10060 (WSAETIMIMOUTOUT)
  • mySocket.state = 9 sckError

At this point, if I run server application A, do RAShangup and RASdial and try to connect to server A, everything works fine.

socket.connect ip, port
socket.close
socket.connect newIP, newPort

, RAShangup RASdial. WSAETIMEDOUT.

-, ?

. , , :

Private Sub closeSocket(ByRef w As Winsock)
  w.Close
  Do While (w.State <> sckClosed)
    DoEvents
  Loop
End Sub
+3
1

, LocalPort winsock . winsock.

, .

: VB6 , .

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