log.error(e);
System.err.println(e);
    static void senderLoop(DatagramSocket sock) {	DataInputStream in;	String          line;	DatagramPacket  packet;	InetAddress     dst;	int             dst_port;	StringTokenizer tok;	StringBuffer    sb;	String          tmp, buf;	byte[]          bbuf;	AckReceiver     ack_receiver=new AckReceiver(sock);	ack_receiver.start();	in=new DataInputStream(System.in);	while(true) {	    try {		System.out.print("> ");		line=in.readLine();		if(line.startsWith("quit") || line.startsWith("exit"))		    break;		tok=new StringTokenizer(line);		try {		    dst=InetAddress.getByName(tok.nextToken());		    dst_port=Integer.parseInt(tok.nextToken());		}		catch(Exception e) {		    log.error(e);		    continue;		}		sb=new StringBuffer();		while(tok.hasMoreTokens()) {		    tmp=tok.nextToken();		    sb.append(tmp + ' ');		}		buf=sb.toString();		System.out.println("sending " + buf);		bbuf=buf.getBytes();		packet=new DatagramPacket(bbuf, bbuf.length, dst, dst_port);		sock.send(packet);	    }	    catch(Exception e) {		log.error(e);		break;	    }	}	ack_receiver.stop();    }