socket error 10093 when trying to reconnect client

Posted on 2005-04-22
Medium Priority
Last Modified: 2013-11-20
I have a socket connection going when my application starts up. Then the user can click on a button to change the port number that the application is connected to. When the button is clicked, I close the socket (CAsynSocket btw), and tried the following in trying to reconnect it, but keep getting error 10093 each time:

Ex: I have a socket:

CAsyncSocket *mySocket;

1) call connect() again  // got 10093 error

2) call create()  
   then call connect()  // same 10093 error

3) mySocket = new CAsyncSocket();
   mySocket->connect()  // same 10093 error

My question: what happens after I close a socket? Do I need to do a complete clean up with WSACleanup() then call WSAStartup again? Does error 10093 mean WSAStartup is not being called?
Question by:jade03
  • 3
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LVL 86

Expert Comment

ID: 13845685
>>Does error 10093 mean WSAStartup is not being called?

The error is


which indeed means that you forgot to

AfxSocketInit ();


WORD wVersionRequested;
WSADATA wsaData;
int err;
wVersionRequested = MAKEWORD( 2, 2 );
err = WSAStartup( wVersionRequested, &wsaData );
if ( err != 0 ) {
    /* Tell the user that we could not find a usable */
    /* WinSock DLL.                                  */

Author Comment

ID: 13846201
yes, I realized that was probably the error...but my question is, I had called that once already on the first connection, should I call it AGAIN after I close the socket in order to reconnect?
LVL 86

Expert Comment

ID: 13846233
>>should I call it AGAIN after I close the socket in order to reconnect?

You don't need to call 'AfxSocketInit ()'/'WSAStartup()' unless you called 'WSACleanup()'
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Author Comment

ID: 13846267
right...that's the thing...I didn't call WSACleanup() after I call close(), but still it won't let me do another connect()...so I'm trying to figure out why...

Accepted Solution

nabehs earned 150 total points
ID: 13849021
I am not sure, but it seems that when you close the socket the socket state data is freed and on the destructor of the state data it calls AfxSocketTerm which class WSACleanup

      if (m_pfnSockTerm != NULL)
 where m_pfnSockTerm points to AfxSocketTerm. This is my guess. so you need to re-call WSAStartup or AfxSocketInit again


Author Comment

ID: 13850717
yes, after fidgiting around with it for a while, it seems to work after I recall WSAStartup and then create() then connect(). Thank you!

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