I have a problem with using UPD under NET framwork.
The problem consist if any client disconnect under UDP protocol
from server ( code below ) it raise exeption 10054 -
It shouldn't be under UDP protocol - becouse this protocol is
connectionless and does not have any notification about closing.
Exeption 10054 is:
An existing connection was forcibly closed by the remote host.
Thanks,
Volodia.
UDP server code (by the way - client done in unmanaged C++) :
Sub ThreadProc()
_ReceivingSocket = New Socket(AddressFamily.InterNetwork, _
SocketType.Dgram, ProtocolType.Udp)
_ReceivingSocket.SetSocketOption(SocketOptionLevel.Socket, _
SocketOptionName.ReuseAddress, 1)
Dim listenEndPoint As IPEndPoint = New IPEndPoint(IPAddress.Any, _Port)
_ReceivingSocket.Bind(listenEndPoint)
Dim state As New StateObject
Dim nodecallback As New AsyncCallback(AddressOf RecieveCallback)
Dim nodeIP As IPEndPoint = New IPEndPoint(IPAddress.Any, 0)
Dim nodeEP As EndPoint = DirectCast(nodeIP, EndPoint)
While NodeListenerRun > 0
ReadDone.Reset()
Try
_ReceivingSocket.BeginReceiveFrom(state.buffer, 0, _
state.BufferSize, SocketFlags.None, nodeEP,
nodecallback, state)
ReadDone.WaitOne()
Catch sex As SocketException
If (sex.ErrorCode = 10040) Then
state.IncreaseBuffer()
Else
SwitchSocketOff()
End If
Catch exp As Exception
CloseListening()
End Try
End While
End sub
Private Shared Sub RecieveCallback(ByVal ar As IAsyncResult)
Try
'
' Get state object
'
Dim state As StateObject = CType(ar.AsyncState, StateObject)
'
' Creates a temporary EndPoint to pass to EndReceiveFrom.
'
Dim sender As New IPEndPoint(IPAddress.Any, 0)
Dim fromEP As EndPoint = CType(sender, EndPoint)
'
' Get number of bytes.
'
Dim bytesRead As Integer = state.workSocket.EndReceiveFrom(ar,
fromEP)
Dim str As String
If bytesRead > 0 Then
str = Encoding.ASCII.GetChars(state.buffer, 0, bytesRead)
'
' Process data
'
ClientResponce(state, fromEP, str)
End If
Catch sex As SocketException
If (sex.ErrorCode = 10054) Then
SwitchSocketOff()
Tracing("Listener RecieveCallback : " & sex.Message)
End If
Catch ex As Exception
Tracing("Listener RecieveCallback error: " & ex.ToString)
End Try
'
' All data was get, so reset event.
'
ReadDone.Set()
End Sub