Java

Get the Type of an Active SSH Channel

Demonstrates the Chilkat Ssh.GetChannelType method, which returns the type of the channel at a zero-based enumeration index. The only argument is the index — an enumeration position, not a channel number. Values include session, x11, forwarded-tcpip, and direct-tcpip.

Background: Paired with GetChannelNumber, this turns the channel collection into a readable inventory of what a connection is currently doing — which channels are running commands (session) versus tunneling TCP traffic (direct-tcpip). That is valuable for diagnostics and for application code that manages several channel kinds at once. An out-of-range index causes the string-returning method to report failure.

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Java

import com.chilkatsoft.*;

public class ChilkatExample {

  static {
    try {
        System.loadLibrary("chilkat");
    } catch (UnsatisfiedLinkError e) {
      System.err.println("Native code library failed to load.\n" + e);
      System.exit(1);
    }
  }

  public static void main(String argv[])
  {
    boolean success = false;

    //  Demonstrates the Ssh.GetChannelType method, which returns the type of the channel at a
    //  zero-based enumeration index.  The only argument is the index, which is an enumeration
    //  position and not a channel number.  Values include "session" and "direct-tcpip".

    CkSsh ssh = new CkSsh();

    int sshPort = 22;
    success = ssh.Connect("ssh.example.com",sshPort);
    if (success == false) {
        System.out.println(ssh.lastErrorText());
        return;
        }

    //  Normally you would not hard-code the password in source.  You should instead obtain it
    //  from an interactive prompt, environment variable, or a secrets vault.
    String password = "mySshPassword";

    success = ssh.AuthenticatePw("mySshLogin",password);
    if (success == false) {
        System.out.println(ssh.lastErrorText());
        return;
        }

    int channelNum = ssh.OpenSessionChannel();
    if (channelNum < 0) {
        System.out.println(ssh.lastErrorText());
        return;
        }

    //  Enumerate the active channels and report each one's number and type.
    int n = ssh.get_NumOpenChannels();
    int i;
    for (i = 0; i <= n - 1; i++) {
        int chNum = ssh.GetChannelNumber(i);
        String chType = ssh.getChannelType(i);
        if (ssh.get_LastMethodSuccess() == false) {
            System.out.println(ssh.lastErrorText());
            return;
            }

        System.out.println("Channel " + chNum + " is of type " + chType);
        }

    ssh.Disconnect();
  }
}