Perl

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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Perl

use chilkat();

$success = 0;

#  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".

$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;
}

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

#  Enumerate the active channels and report each one's number and type.
$n = $ssh->get_NumOpenChannels();

for ($i = 0; $i <= $n - 1; $i++) {
    $chNum = $ssh->GetChannelNumber($i);
    $chType = $ssh->getChannelType($i);
    if ($ssh->get_LastMethodSuccess() == 0) {
        print $ssh->lastErrorText() . "\r\n";
        exit;
    }

    print "Channel " . $chNum . " is of type " . $chType . "\r\n";
}

$ssh->Disconnect();