Perl

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.

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Perl

use chilkat();

$success = 0;

#  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.

$ssh = chilkat::CkSsh->new();

$sshPort = 22;
$success = $ssh->Connect("ssh.example.com",$sshPort);
if ($success == 0) {
    print $ssh->lastErrorText() . "\r\n";
    exit;
}

#  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.
$password = "mySshPassword";

$success = $ssh->AuthenticatePw("mySshLogin",$password);
if ($success == 0) {
    print $ssh->lastErrorText() . "\r\n";
    exit;
}

#  Open a session channel.  A negative return value indicates failure.
$channelNum = $ssh->OpenSessionChannel();
if ($channelNum < 0) {
    print $ssh->lastErrorText() . "\r\n";
    exit;
}

#  Request that the allocated terminal not echo input.
$success = $ssh->SetTtyMode("ECHO",0);
if ($success == 0) {
    print $ssh->lastErrorText() . "\r\n";
    exit;
}

#  The modes set above are included in the PTY request.
$success = $ssh->SendReqPty($channelNum,"xterm",80,24,0,0);
if ($success == 0) {
    print $ssh->lastErrorText() . "\r\n";
    exit;
}

$success = $ssh->SendReqShell($channelNum);
if ($success == 0) {
    print $ssh->lastErrorText() . "\r\n";
    exit;
}

$ssh->Disconnect();