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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Chilkat2 Perl

use strict;
use warnings;
use Chilkat2;

# 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.

my $ssh = Chilkat2::Ssh->new;

my $sshPort = 22;
my $success = $ssh->Connect('ssh.example.com', $sshPort);
if (!$success) {
    print $ssh->LastErrorText, "\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.
my $password = 'mySshPassword';

$success = $ssh->AuthenticatePw('mySshLogin', $password);
if (!$success) {
    print $ssh->LastErrorText, "\n";
    exit;
}

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

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

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

$success = $ssh->SendReqShell($channelNum);
if (!$success) {
    print $ssh->LastErrorText, "\n";
    exit;
}

$ssh->Disconnect();