Call this member function to request event notification for a socket.
BOOL AsyncSelect( long lEvent = FD_READ | FD_WRITE | FD_OOB | FD_ACCEPT | FD_CONNECT | FD_CLOSE );
Nonzero if the function is successful; otherwise 0, and a specific error code can be retrieved by calling GetLastError. The following errors apply to this member function:
WSANOTINITIALISED A successful AfxSocketInit must occur before using this API.
WSAENETDOWN The Windows Sockets implementation detected that the network subsystem failed.
WSAEINVAL Indicates that one of the specified parameters was invalid.
WSAEINPROGRESS A blocking Windows Sockets operation is in progress.
This function is used to specify which MFC callback notification functions will be called for the socket. AsyncSelect automatically sets this socket to nonblocking mode. For more information, see the article Windows Sockets: Socket Notifications.