I have written an async UDP client to talk to a server at my company. When I run on my developer machine all is well. When I deploy to another machine I get a socket exception on EndReceive the first time I send data over the socket. My dev box is Win7 and I have deployed to both an XP SP3 machine and a Server 2003 R2 machine. Below is the receive code:
Private Sub ReceiveCallback(ByVal ar As IAsyncResult)
Try
' Retrieve the state object and the client socket
from the asynchronous state object.'
Dim state As StateObj = CType(ar.AsyncState, StateObj)
Dim client As Socket = state.sockArg
' Read data from the remote device.'
Dim bytesRead As Integer
receiveDone.WaitOne(Timeout.Infinite)
bytesRead = client.EndReceive(ar)
If bytesRead > 0 Then
Dim s As String = Encoding.ASCII.GetString(state.buffer, 0, bytesRead)
parsedata(s)
End If
Catch SockEx As SocketException
mlog.Error(String.Format("ID={1} {0} SocketError={2}", SockEx.Message, ID.ToString, SockEx.SocketErrorCode.ToString), SockEx)
Catch ox As System.ObjectDisposedException
mlog.Warn(String.Format("Object Disposed ID={0}", ID.ToString))
Catch ex As Exception
mlog.Error(String.Format("{1} ID={0}", 开发者_StackOverflow社区ID.ToString, ex.Message), ex)
End Try
End Sub 'ReceiveCallback
The exception I get is:
System.Net.Sockets.SocketException: The I/O operation has been aborted because of either a thread exit or an application request at System.Net.Sockets.Socket.EndReceive(IAsyncResult asyncResult) at RTSPc.Connection.ReceiveCallback(IAsyncResult ar)
The SocketException is OperationAborted
It's likely that the reason that it doesn't fail on your dev box is that the underlying behaviour of the I/O system was changed in Vista so that overlapped I/O that was issued by a thread is no longer cancelled when the thread exits.
See this posting on my blog about this: http://www.lenholgate.com/blog/2008/02/major-vista-overlapped-io-change.html
Now, why you're getting the problem on XP is the real question and to answer that we'd probably need to know a little more about how you're issuing your overlapped I/O requests and from where. Are you running any threads of your own? Do they issue any I/O requests?
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