public POP3connection(TcpClient cli)
{
c = cli;
lastLine = new byte[10240];
buffer = new byte[10240];
c.Client.BeginReceive(buffer, 0, buffer.Length, SocketFlags.None, new AsyncCallback(dataRec), null);
t = new Thread(new ThreadStart(check));
t.IsBackground = true;
t.Start();
}