phpseclib\Net\SSH2::_get_interactive_channel PHP Method

    function _get_interactive_channel()
    {
        switch (true) {
            case $this->in_subsystem:
                return self::CHANNEL_SUBSYSTEM;
            case $this->in_request_pty_exec:
                return self::CHANNEL_EXEC;
            default:
                return self::CHANNEL_SHELL;
        }
    }