C# TCP Async EndReceive() throws InvalidOperationException ONLY on Windows XP 32-bit

Posted by James Farmer on Stack Overflow See other posts from Stack Overflow or by James Farmer
Published on 2013-11-07T21:43:27Z Indexed on 2013/11/07 21:54 UTC
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I have a simple C# Async Client using a .NET socket that waits for timed messages from a local Java server used for automating commands. The messages come in asynchronously and is written to a ring buffer. This implementation seems to work fine on Windows Vista/7/8 and OSX, but will randomly throw this exception while it's receiving a message from the local Java server:

Unhandled Exception: System.InvalidOperationException: EndReceive can only be called once for each asynchronous operation.
    at System.Net.Sockets.Socket.EndReceive(IAsyncResult asyncResult, SocketError& errorCode)
    at System.Net.Sockets.Socket.EndReceive(IAsyncResult asyncResult)
    at SocketTest.Controller.RecvAsyncCallback(IAsyncResult ar)
    at System.Net.LazyAsyncResult.Complete(IntPtr userToken)
    ...

I've looked online for this error, but have found nothing really helpful. This is the code where it seems to break:

/// <summary>
/// Callback to receive socket data
/// </summary>
/// <param name="ar">AsyncResult to pass to End</param>
private void RecvAsyncCallback(IAsyncResult ar)
{
    // The exception will randomly happen on this call
    int bytes = _socket.EndReceive(_recvAsyncResult);

    // check for connection closed
    if (bytes == 0)
    {
        return;
    }

    _ringBuffer.Write(_buffer, 0, bytes);

    // Checks buffer
    CheckBuffer();

    _recvAsyncResult = _sock.BeginReceive(_buffer, 0, _buffer.Length, SocketFlags.None, RecvAsyncCallback, null);
}

The error doesn't happen on any particular moment except in the middle of receiving a message. The message itself can be any length for this to happen, and the exception can happen right away, or sometimes even up to a minute of perfect communication.

I'm pretty new with sockets and network communication, and I feel I might be missing something here. I've tested on at least 8 different computers, and the only similarity with the computers that throw this exception is that their OS is Windows XP 32-bit.

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