Server socket problem.. client sees connection close before all data received

From: CHRISM (chris_at_sorry.no.spam.com)
Date: 11/12/04 

Date: Thu, 11 Nov 2004 20:23:01 -0500

Hiya,

Been trying to figure this one out. I've written a very simple server
in VB.NET that listens for client connections, then spits out a bunch
of text and then closes the connection. Much like an HTTP server
might do when you request a web page.

The server socket listens for connections using BeginAccept(); and
here's the simple handler function that gets called when a client
connects.

The Problem: I use TELNET from another machine to connect to the
server. I should see the numbers "1 2 3 4 ..." all the way up to
9000. But I usually get to only 5200 or sometimes into the 7000's
before telnet says "Connection to host lost."

I added a LingerOption, for 30 seconds, but that seems to have no
effect. I also tried enabling the "NoDelay" option and that seemed to
make no difference either.

Does anyone know what's going on and how to fix it?

Thanks,
// CHRIS

///////////////////////////////////////////////////////////////////

Public Sub SRV_SOCK_ACCEPT(ByVal ar As System.IAsyncResult)

        'Get Server Socket
        Dim theServerSocket As Socket = CType(ar.AsyncState, Socket)
        'Accept Connection
        Dim theClientSock As Socket = theServerSocket.EndAccept(ar)
        'Set Linger Option
        Dim lingerOptionValue As New LingerOption(True, 30)
        theClientSock.SetSocketOption(SocketOptionLevel.Socket, _
          SocketOptionName.Linger, lingerOptionValue)

        
        Dim n As Integer 'Counter
        Dim theBytes() As Byte 'Byte array for encoding text

        For n = 1 To 9000
          theBytes = Encoding.ASCII.GetBytes(String.Format("{0} ", n))
          theClientSock.Send(theBytes)
        Next

        theClientSock.Close()

End Sub

///////////////////////////////////////////////////////////////////

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