What is the TcpListener.BeginAcceptTcpClient I/O Model in DotnetCore 1.0.x

Question

I already know the BeginXXX(AMP) or XXXAsync(TAP) use IOCP in .NetFramework , then now I want to construct httpServer build on dotnetcore . so I need to know the inner mechanism.

My pervious version in .NetworkFramework like the follow code:

private void continueAccept(TcpListener tcpListener,Action<TcpClient> processConnection)
    {

        //IOCP
        tcpListener.BeginAcceptTcpClient(ar =>
        {

            if (listening)
                continueAccept(tcpListener, processConnection);
            else
                return;

            try
            {

                TcpClient tcpClient = tcpListener.EndAcceptTcpClient(ar);

                acceptCount++;

                tcpClient.SendTimeout = 300000;
                tcpClient.ReceiveTimeout = 300000;

                ConsoleHost1.trace(System.Diagnostics.TraceEventType.Verbose, $"Client Accept { tcpClient.Client.RemoteEndPoint.ToString()}");

                ThreadPool.QueueUserWorkItem((o) => {

                    processConnection((TcpClient)o);

                }, tcpClient);

            }
            catch (Exception e)
            {
                ConsoleHost1.trace(System.Diagnostics.TraceEventType.Error, $"acceptTD:{e.Message}");
            }

        }, null);

    }

    public void startListen(Action<TcpClient> processConnection)
    {

        tcpListener = new TcpListener(IPAddress.Parse("0.0.0.0"), port1);
        tcpListener.Start(maxQueue1);
        listening = true;

        continueAccept(tcpListener, processConnection);

    }

Answer 1

I have just resolved.

In windows:

AcceptAsync use the AcceptEx+SocketAsyncEventArgs(IOCP)
BeginAccept use the AcceptEx+SafeNativeOverlapped(IOCP)

Reference from: https://github.com/dotnet/corefx/blob/release/1.0.0/src/System.Net.Sockets/src/System/Net/Sockets/Socket.Windows.cs https://github.com/dotnet/corefx/blob/release/1.0.0/src/System.Net.Sockets/src/System/Net/Sockets/SocketAsyncEventArgs.Windows.cs

In Unix-like OS:

AcceptAsync Or AcceptAsync use Interop.Sys.Accept + ThreadPool in user mode.

Reference from: https://github.com/dotnet/corefx/blob/release/1.0.0/src/System.Net.Sockets/src/System/Net/Sockets/SocketPal.Unix.cs https://github.com/dotnet/corefx/blob/release/1.0.0/src/System.Net.Sockets/src/System/Net/Sockets/SocketAsyncContext.Unix.cs