Imports System.Net
Imports System.Net.Sockets
Imports System.Threading
Imports System.IO

Public Class FTPServer

  Public Shared Sub Main()
    Dim serverSocket As System.Net.Sockets.Socket

    Try
      Dim hostName As String = Dns.GetHostName()
      Dim serverIP As IPAddress = Dns.Resolve(hostName).AddressList(0)

      ' FTP Server Port = 21
      Dim Port As String = "21"
      Dim serverHost As New IPEndPoint(serverIP, Int32.Parse(Port))

      serverSocket = New Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp)

      serverSocket.Bind(serverHost)

      ' Backlog = 100
      serverSocket.Listen(100)

      Console.WriteLine("FTP server started at: " & serverHost.Address.ToString() & ":" & Port)

      Dim FTPSession As New FTPSession(serverSocket)

      Dim serverThread As New Thread(New ThreadStart(AddressOf FTPSession.ProcessThread))

      serverThread.Start()

    Catch ex As Exception
      Console.WriteLine(ex.StackTrace.ToString())
    End Try
  End Sub
End Class