Net_SSH2::startSubsystem PHP Method

    function startSubsystem($subsystem)
    {
        $this->window_size_server_to_client[NET_SSH2_CHANNEL_SUBSYSTEM] = $this->window_size;
        $packet = pack('CNa*N3', NET_SSH2_MSG_CHANNEL_OPEN, strlen('session'), 'session', NET_SSH2_CHANNEL_SUBSYSTEM, $this->window_size, 0x4000);
        if (!$this->_send_binary_packet($packet)) {
            return false;
        }
        $this->channel_status[NET_SSH2_CHANNEL_SUBSYSTEM] = NET_SSH2_MSG_CHANNEL_OPEN;
        $response = $this->_get_channel_packet(NET_SSH2_CHANNEL_SUBSYSTEM);
        if ($response === false) {
            return false;
        }
        $packet = pack('CNNa*CNa*', NET_SSH2_MSG_CHANNEL_REQUEST, $this->server_channels[NET_SSH2_CHANNEL_SUBSYSTEM], strlen('subsystem'), 'subsystem', 1, strlen($subsystem), $subsystem);
        if (!$this->_send_binary_packet($packet)) {
            return false;
        }
        $this->channel_status[NET_SSH2_CHANNEL_SUBSYSTEM] = NET_SSH2_MSG_CHANNEL_REQUEST;
        $response = $this->_get_channel_packet(NET_SSH2_CHANNEL_SUBSYSTEM);
        if ($response === false) {
            return false;
        }
        $this->channel_status[NET_SSH2_CHANNEL_SUBSYSTEM] = NET_SSH2_MSG_CHANNEL_DATA;
        $this->bitmap |= NET_SSH2_MASK_SHELL;
        $this->in_subsystem = true;
        return true;
    }