Start a Remote Shell with QuickShell

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Demonstrates the Chilkat Ssh.QuickShell method, which starts a remote shell using the simplified sequence OpenSessionChannel → SendReqPty → SendReqShell. It takes no arguments and returns the shell channel number, or -1 on failure. The default PTY size is 80 columns by 24 rows.

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.QuickShell method, which starts a remote shell using the simplified
    //  sequence OpenSessionChannel, SendReqPty, and SendReqShell.  It takes no arguments and returns
    //  the shell channel number, or -1 on failure.  The default PTY size is 80 columns by 24 rows.

    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;
        }

    //  Start the shell.  Note that QuickShell allocates a PTY, so the remote shell runs
    //  interactively: it prints a command prompt and echoes the commands that are sent to it.
    int channelNum = ssh.QuickShell();
    if (channelNum < 0) {
        System.out.println(ssh.lastErrorText());
        return;
        }

    //  QuickShell returns as soon as the shell request is accepted -- it does not wait for or
    //  consume the initial login text or prompt.
    success = ssh.ChannelSendString(channelNum,"uname -a; echo DONE_MARKER\n","utf-8");
    if (success == false) {
        System.out.println(ssh.lastErrorText());
        return;
        }

    //  IMPORTANT: Set a read timeout before receiving until a match.  ReadTimeoutMs defaults to 0,
    //  which means no limit -- without it, this call waits forever if the received data never
    //  contains a match.
    ssh.put_ReadTimeoutMs(15000);

    boolean caseSensitive = false;
    success = ssh.ChannelReceiveUntilMatch(channelNum,"DONE_MARKER","utf-8",caseSensitive);
    if (success == false) {
        System.out.println(ssh.lastErrorText());
        return;
        }

    String output = ssh.getReceivedText(channelNum,"utf-8");
    if (ssh.get_LastMethodSuccess() == false) {
        System.out.println(ssh.lastErrorText());
        return;
        }

    System.out.println(output);

    ssh.Disconnect();
  }
}