phpseclib\Net\SSH2::_get_open_channel PHP Method

    function _get_open_channel()
    {
        $channel = self::CHANNEL_EXEC;
        do {
            if (isset($this->channel_status[$channel]) && $this->channel_status[$channel] == NET_SSH2_MSG_CHANNEL_OPEN) {
                return $channel;
            }
        } while ($channel++ < self::CHANNEL_SUBSYSTEM);
        return false;
    }