winsock connect function is working only on high speed connection - vba

Question

I'm using winsock in my VB6 application, this is my code:
Private Sub Form_Load()
With Winsock1
.Close
.RemoteHost = Hostip
.RemotePort = port number
.Connect
End With
End Sub
My problem is when I'm using a high speed connection (4G) the connection works fine but using other connections like (3G,wise...) it returns the following message:
the attempt to connect timed out
How do I remedy this?

Answer 1

It sounds like you need to set a longer connection timeout. There is no way to do this directly with the control. Below is a modified sample from a retired KB article. The orignal code does not include the SO_SNDTIMEO, or SO_RCVTIMEO options.
Option Explicit
' Error returned by Winsock API.
Const SOCKET_ERROR = -1
' Level number for (get/set)sockopt() to apply to socket itself.
Const SOL_SOCKET = 65535 ' Options for socket level.
Const IPPROTO_TCP = 6 ' Protocol constant for TCP.
' option flags per socket
Const SO_DEBUG = &H1& ' Turn on debugging info recording
Const SO_ACCEPTCONN = &H2& ' Socket has had listen() - READ-ONLY.
Const SO_REUSEADDR = &H4& ' Allow local address reuse.
Const SO_KEEPALIVE = &H8& ' Keep connections alive.
Const SO_DONTROUTE = &H10& ' Just use interface addresses.
Const SO_BROADCAST = &H20& ' Permit sending of broadcast msgs.
Const SO_USELOOPBACK = &H40& ' Bypass hardware when possible.
Const SO_LINGER = &H80& ' Linger on close if data present.
Const SO_OOBINLINE = &H100& ' Leave received OOB data in line.
Const SO_DONTLINGER = Not SO_LINGER
Const SO_EXCLUSIVEADDRUSE = Not SO_REUSEADDR ' Disallow local address reuse.
' Additional options.
Const SO_SNDBUF = &H1001& ' Send buffer size.
Const SO_RCVBUF = &H1002& ' Receive buffer size.
Const SO_ERROR = &H1007& ' Get error status and clear.
Const SO_TYPE = &H1008& ' Get socket type - READ-ONLY.
' TCP Options
Const TCP_NODELAY = &H1& ' Turn off Nagel Algorithm.
' linger structure
Private Type LINGER_STRUCT
l_onoff As Integer ' Is linger on or off?
l_linger As Integer ' Linger timeout in seconds.
End Type
'timeout structure
Private Type TIMEOUT_STRUCT
tv_sec As Long 'seconds
tv_usec As Long 'milliseconds
End Type
'Timeout options
Const SO_SNDTIMEO = &H1005& 'send timeout
Const SO_RCVTIMEO = &H1006& 'receive timeout
' Winsock API declares
Private Declare Function setsockopt Lib "wsock32.dll" (ByVal s As Long, ByVal level As Long, ByVal optname As Long, optval As Any, ByVal optlen As Long) As Long
Private Declare Function getsockopt Lib "wsock32.dll" (ByVal s As Long, ByVal level As Long, ByVal optname As Long, optval As Any, optlen As Long) As Long
Private Sub Command1_Click()
' Read all the options and present in a message box.
Dim socket As Long
socket = Winsock1.SocketHandle
If socket = 0 Then
MsgBox "No Socket"
Else
MsgBox "Socket Options:" & vbCrLf & _
" SO_DEBUG: " & CStr(GetSocketOption(socket, SOL_SOCKET, SO_DEBUG)) & vbCrLf & _
" SO_ACCEPTCONN: " & CStr(GetSocketOption(socket, SOL_SOCKET, SO_ACCEPTCONN)) & vbCrLf & _
" SO_REUSEADDR: " & CStr(GetSocketOption(socket, SOL_SOCKET, SO_REUSEADDR)) & vbCrLf & _
" SO_KEEPALIVE: " & CStr(GetSocketOption(socket, SOL_SOCKET, SO_KEEPALIVE)) & vbCrLf & _
" SO_DONTROUTE: " & CStr(GetSocketOption(socket, SOL_SOCKET, SO_DONTROUTE)) & vbCrLf & _
" SO_BROADCAST: " & CStr(GetSocketOption(socket, SOL_SOCKET, SO_BROADCAST)) & vbCrLf & _
" SO_USELOOPBACK: " & CStr(GetSocketOption(socket, SOL_SOCKET, SO_USELOOPBACK)) & vbCrLf & _
" SO_LINGER: " & CStr(GetSocketOption(socket, SOL_SOCKET, SO_LINGER)) & vbCrLf & _
" SO_OOBINLINE: " & CStr(GetSocketOption(socket, SOL_SOCKET, SO_OOBINLINE)) & vbCrLf & _
" SO_DONTLINGER: " & CStr(GetSocketOption(socket, SOL_SOCKET, SO_DONTLINGER)) & vbCrLf & _
" SO_EXCLUSIVEADDRUSE: " & CStr(GetSocketOption(socket, SOL_SOCKET, SO_EXCLUSIVEADDRUSE)) & vbCrLf & _
" SO_SNDBUF: " & CStr(GetSocketOption(socket, SOL_SOCKET, SO_SNDBUF)) & vbCrLf & _
" SO_RCVBUF: " & CStr(GetSocketOption(socket, SOL_SOCKET, SO_RCVBUF)) & vbCrLf & _
" SO_ERROR: " & CStr(GetSocketOption(socket, SOL_SOCKET, SO_ERROR)) & vbCrLf & _
" SO_TYPE: " & CStr(GetSocketOption(socket, SOL_SOCKET, SO_TYPE)) & vbCrLf & vbCrLf & _
"TCP Options:" & vbCrLf & _
" TCP_NODELAY: " & CStr(GetSocketOption(socket, IPPROTO_TCP, TCP_NODELAY))
End If
End Sub
Private Sub Command2_Click()
Dim lResult As Long ' Results of 1st option.
Dim tout As TIMEOUT_STRUCT
If (Winsock1.Protocol = sckTCPProtocol) Then
tout.tv_sec = 10
tout.tv_usec = 0
lResult = setsockopt(Winsock1.SocketHandle, SOL_SOCKET, SO_SNDTIMEO, tout, LenB(tout))
If (lResult = SOCKET_ERROR) Then
MsgBox "Error setting SO_SNDTIMEO option: " & Translate_DLL_Error(Err.LastDllError)
Else
MsgBox "SO_SNDTIMEO option set."
End If
End If
End Sub
Public Function GetSocketOption(lSocket As Long, lLevel As Long, lOption As Long) As Long
Dim lResult As Long ' Result of API call.
Dim lBuffer As Long ' Buffer to get value into.
Dim lBufferLen As Long ' len of buffer.
Dim linger As LINGER_STRUCT
' Linger requires a structure so we will get that option differently.
If (lOption <> SO_LINGER) And (lOption <> SO_DONTLINGER) Then
lBufferLen = LenB(lBuffer)
lResult = getsockopt(lSocket, lLevel, lOption, lBuffer, lBufferLen)
Else
lBufferLen = LenB(linger)
lResult = getsockopt(lSocket, lLevel, lOption, linger, lBufferLen)
lBuffer = linger.l_onoff
End If
If (lResult = SOCKET_ERROR) Then
GetSocketOption = Err.LastDllError
Else
GetSocketOption = lBuffer
End If
End Function
Private Sub Form_Load()
Winsock1.Bind 8377 ' Set up socket enough to get nonzero socket. handle
End Sub
You can find the original article at https://support.microsoft.com/en-us/kb/237688