JavaScript

Set a TTY Mode for an SSH PTY Request

Demonstrates the Chilkat Ssh.SetTtyMode method, which adds or updates one TTY mode to be included in a later SendReqPty request. The first argument is the mode name and the second is its integer value. Call it once per mode, before requesting the PTY.

Background: TTY modes are the terminal settings a PTY is created with — the same knobs stty exposes. The classic use is SetTtyMode("ECHO", 0), which stops the terminal from echoing input; that is how a password prompt keeps typed characters off the screen. Modes accumulate on the object and are sent with the next PTY request.

Note

This example is intended for running within a Chilkat.Js embedded JavaScript engine. All Chilkat JavaScript examples require Chilkat v11.4.0 or greater.

JavaScript

var success = false;

//  Demonstrates the Ssh.SetTtyMode method, which adds or updates one TTY mode to be included in
//  a later SendReqPty request.  The 1st argument is the mode name and the 2nd is its integer
//  value.  Call it once per mode, before SendReqPty.

var ssh = new CkSsh();

var sshPort = 22;
success = ssh.Connect("ssh.example.com",sshPort);
if (success == false) {
    console.log(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.
var password = "mySshPassword";

success = ssh.AuthenticatePw("mySshLogin",password);
if (success == false) {
    console.log(ssh.LastErrorText);
    return;
}

//  Open a session channel.  A negative return value indicates failure.
var channelNum = ssh.OpenSessionChannel();
if (channelNum < 0) {
    console.log(ssh.LastErrorText);
    return;
}

//  Request that the allocated terminal not echo input.
success = ssh.SetTtyMode("ECHO",0);
if (success == false) {
    console.log(ssh.LastErrorText);
    return;
}

//  The modes set above are included in the PTY request.
success = ssh.SendReqPty(channelNum,"xterm",80,24,0,0);
if (success == false) {
    console.log(ssh.LastErrorText);
    return;
}

success = ssh.SendReqShell(channelNum);
if (success == false) {
    console.log(ssh.LastErrorText);
    return;
}

ssh.Disconnect();