How to simulate Ctrl-Break as a string?

What do you mean by 'upto host'?

I set up a telenet session and break up the program on host. Normally I can use Ctrl+Break to do this if I use directly the host. Now I have to simulate this "Ctrl+Break" and send upto the host.

How are you doing the telnet bit?

It has little to do with telnet. I don't want to break up the telnet session but the program running on the host.

So you mean 'how do i stop the Java program, that i'd normally do with Ctrl-Break, programmatically?'

No. I used java Swing to program a Telnet-GUI. I use this GUI to send commans via telnet to run the program on host. Now I want to break up the program. So I have to send a command of "Ctrl+Break" via telnet to the host.

Why in that case do you say 'It has little to do with telnet'? It seems to me to have everything to do with telnet. You need to send whatever the quit command is in telnet

Of course you could just be brutal and close the stream. It would be preferable to send a 'quit' command first though

the program running on the host dosen't accept "quit" but just "Ctrl+Break".

There is no command 'quit' in telnet of course.

>>I use this GUI to send commans via telnet to run the program on host

Can you tell me exactly how the telnet bit of the above is being done?

I use the Thor Telnet Classes to do the telnet connection:
http://mrl.nyu.edu/~danielk/telnet/

My program looks like:
...
private URLConnection urlConnection;
private OutputStream out;
...
out=urlConnection.getOutputStream();
...

try{
 URL url=new URL("telnet", hostIP, port, "",
  new thor.net.URLStreamHandler());
  urlConnection=url.openConnection();
  urlConnection.connect();
  if (urlConnection instanceof TelnetURLConnection) {
      ((TelnetURLConnection)urlConnection).
      setTelnetTerminalHandler(new SimpleTelnetTerminalHandler());
  }
 out=urlConnection.getOutputStream();
...

If I send a command upto host via telnet, I call this function:
...
for(int i = 0; i< command.length(); i++)
{
  out.write(command.charAt(i));
}
...

Why not just call

out.close();
urlConnection.disconnect();

?

out.close() will close the telnet session or something similar. But I have to stop or break up the program, for example an editor, running on the host first.

Besides, if I break up the program running on the host doese't mean I will close the telnet session. I wan to do something else on the host.