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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Chilkat2 Perl

use strict;
use warnings;
use Chilkat2;

# 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".

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;
}

my $channelNum = $ssh->OpenSessionChannel();
if ($channelNum < 0) {
    print $ssh->LastErrorText, "\n";
    exit;
}

# Enumerate the active channels and report each one's number and type.
my $n = $ssh->NumOpenChannels;
for my $i (0 .. $n - 1) {
    my $chNum = $ssh->GetChannelNumber($i);
    my $chType = $ssh->GetChannelType($i);
    if (!$ssh->LastMethodSuccess) {
        print $ssh->LastErrorText, "\n";
        exit;
    }

    print 'Channel ', $chNum, ' is of type ', $chType, "\n";
}

$ssh->Disconnect();