added second client for receiving udp messages

UdpTestApp/Program.cs

@@ -9,7 +9,7 @@ public class Program
     private static StringComparer stringComparer = StringComparer.OrdinalIgnoreCase;
     private static bool _continue;
     private static Thread readThread;
-    private static UdpClient udpClient = null;
+    private static UdpClient udpClient = null, receivingUdpClient = null;
 
     public static bool applicationQuitRequested { get; private set; }
 
@@ -52,12 +52,13 @@ public class Program
 
                     try
                     {
-                        udpClient = new UdpClient(11000);
+                        udpClient = new UdpClient();
+                        receivingUdpClient = new UdpClient(11001);
                         udpClient.Connect(hostname, port);
                     }
-                    catch (Exception)
+                    catch (Exception ex)
                     {
-                        Console.WriteLine($"Could not connect to endpoint.");
+                        Console.WriteLine($"Could not create UDP client. \n {ex}");
                         break;
                     }
 
@@ -97,6 +98,8 @@ public class Program
                     readThread.Join(TimeSpan.FromSeconds(2));
                     //readThread.Abort();
                     readThread = null;
+                    receivingUdpClient.Close();
+                    receivingUdpClient = null;
                     udpClient.Close();
                     udpClient = null;
                     Console.WriteLine("Closed connection.");
@@ -128,7 +131,7 @@ public class Program
                 IPEndPoint RemoteIpEndPoint = new IPEndPoint(IPAddress.Any, 0);
 
                 // Blocks until a message returns on this socket from a remote host.
-                Byte[] receiveBytes = udpClient.Receive(ref RemoteIpEndPoint);
+                Byte[] receiveBytes = receivingUdpClient.Receive(ref RemoteIpEndPoint);
                 string returnData = Encoding.ASCII.GetString(receiveBytes);
 
                 // Uses the IPEndPoint object to determine which of these two hosts responded.