private void SendCommand(string command)
{
Byte[] cmd = Encoding.ASCII.GetBytes((command + "\r\n").ToCharArray());
#if (FTP_DEBUG)
if (command.Length > 3 && command.Substring(0, 4) == "PASS")
Console.WriteLine("\rPASS xxx");
else
Console.WriteLine("\r" + command);
#endif
main_sock.Send(cmd, cmd.Length, 0);
}