Create 2.md

Author: davidfowl

2.md

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+## Asynchronous Socket Server
+
+Below is a modern asynchronous server using modern .NET APIs:
+- Task based APIs for asynchronous accept/read/write
+- Range syntax for slicing the buffer
+
+```C#
+public static async Task AsynchronousEchoServer()
+{
+    using var listenSocket = new Socket(SocketType.Stream, ProtocolType.Tcp);
+    listenSocket.Bind(new IPEndPoint(IPAddress.Loopback, 8080));
+
+    Console.WriteLine($"Listening on {listenSocket.LocalEndPoint}");
+
+    listenSocket.Listen();
+
+    while (true)
+    {
+        // Wait for a new connection to arrive
+        var connection = await listenSocket.AcceptAsync();
+
+        // We got a new connection spawn a task to so that we can echo the contents of the connection
+        _ = Task.Run(async () =>
+        {
+            var buffer = new byte[4096];
+            try
+            {
+                while (true)
+                {
+                    int read = await connection.ReceiveAsync(buffer, SocketFlags.None);
+                    if (read == 0)
+                    {
+                        break;
+                    }
+                    await connection.SendAsync(buffer[..read], SocketFlags.None);
+                }
+            }
+            finally
+            {
+                connection.Dispose();
+            }
+        });
+    }
+}
+```