Function ConnectSock(ByVal Host$, ByVal Port&, ByVal HWndToMsg&, ByVal Async%) _
  As Long
    Dim s&, SelectOps&, Dummy&
    Dim RCVTIMEO As Long
    Dim sockin As sockaddr
    Dim ret As Long
 
    'sockin = saZero 'Dummy
    sockin.sin_family = AF_INET
    sockin.sin_port = htons(Port) ' Diese Funktion konvertiert eine 
    ' Integer-Zahl in einen Netzwerk Byte-Reihenfolge.
 
    If sockin.sin_port = INVALID_SOCKET Then
        ConnectSock = INVALID_SOCKET
        MsgBox "INVALID_SOCKET"
        Exit Function
    End If
 
    sockin.sin_addr = GetHostByNameAlias(Host$)
 
    If sockin.sin_addr = INADDR_NONE Then
        ConnectSock = INVALID_SOCKET
        MsgBox "INVALID_SOCKET"
        Exit Function
    End If
 
 
    s = socket(AF_INET, SOCK_RAW, IPPROTO_IP) 'erstellt ein Winsock-Socket
    ' Erwartet eine der "af" konstanten die beschreiben welcher art der 
    ' Adresstyp des Protokolls ist.
    ' Erwartet eine der "prototype"-Konstanten die beschreiben welcher Typ des 
    ' Protokolls benutzt werden soll.
    ' Erwartet das Protokoll der Verbindung, für das Internet kann hier der 
    ' wert "0" übergegeben werden.
 
    If s < 0 Then
        ConnectSock = INVALID_SOCKET
        MsgBox "INVALID_SOCKET"
        Exit Function
    End If
 
 
RCVTIMEO = 5000
 
ret = setsockopt(s, SOL_SOCKET, SO_RCVTIMEO, (RCVTIMEO), 4) 'The setsockopt 
' function sets a socket option.
'Level at which the option is defined. Example: SOL_SOCKET.
'SO_RCVTIMEO     int     Receives time-out in milliseconds (available in the 
' Microsoft implementation of Windows Sockets 2).
'When using the recv function, if no data arrives during the period specified 
' in SO_RCVTIMEO, the recv function completes. In
'Windows versions prior to Windows 2000, any data received subsequently fails 
' with WSAETIMEDOUT. In Windows 2000 and later,
'if no data arrives within the period specified in SO_RCVTIMEO the recv 
' function returns WSAETIMEDOUT, and if data is received, recv returns SUCCESS.
If ret <> 0 Then
    MsgBox "setsockopt failed"
    If s > 0 Then Dummy = closesocket(s)
    Exit Function
End If
 
'we could check if setsockopt did ok...
'Dim v As Long
'ret = getsockopt(s, SOL_SOCKET, &H1006, v, 4)
'Debug.Print v
 
ret = bind(s, sockin, Len(sockin)) ' The bind function associates a local 
' address with a socket.
 
If ret <> 0 Then
     If s > 0 Then Dummy = closesocket(s)
     MsgBox "bind failed"
     Exit Function
End If
 
 
Dim lngInBuffer As Long
Dim lngBytesReturned As Long
Dim lngOutBuffer As Long
 
lngInBuffer = 1
ret = WSAIoctl(s, SIO_RCVALL, lngInBuffer, Len(lngInBuffer), lngOutBuffer, Len( _
  lngOutBuffer), lngBytesReturned, ByVal 0, ByVal 0) ' The WSAIoctl function 
' controls the mode of a socket.
'Enables a socket to receive all IP packets on the network. The socket handle 
' passed to the WSAIoctl function must be of AF_INET address family,
'SOCK_RAW socket type, and IPPROTO_IP protocol. The socket also must be bound 
' to an explicit local interface, which means that you cannot bind toINADDR_ANY.
'Once the socket is bound and the ioctl set, calls to the WSARecv or recv 
' functions return IP datagrams passing through the given interface. Note that 
' you
'must supply a sufficiently large buffer. Setting this ioctl requires 
' Administrator privilege on the local computer. SIO_RCVALL is available in 
' Windows 2000 and later versions of Windows.
 
If ret <> 0 Then
    If s > 0 Then Dummy = closesocket(s)
    MsgBox "WSAIoctl failed"
    Exit Function
End If
 
SelectOps = FD_READ 'Or FD_WRITE Or FD_CONNECT Or FD_CLOSE
ret = WSAAsyncSelect(s, HWndToMsg, WINSOCKMSG, ByVal SelectOps) ' The 
' WSAAsyncSelect function requests Windows message-based notification of 
' network events for a socket.
If ret <> 0 Then
    If s > 0 Then Dummy = closesocket(s)
    ConnectSock = INVALID_SOCKET
    MsgBox "INVALID_SOCKET"
    Exit Function
End If
 
ConnectSock = s
End Function