按crtl+c之后弹出信息：[INFO] [1713769737.106169624] [rclcpp]: signal_handler(signum=2)

gravity

这是我在学习ros2通信基础的时候遇到的问题，以下是我的代码，我的代码和网上提供的代码整体逻辑应该是一致的，但是我在终端按crtl+c的时候会弹出signal_handler(signum=2)，我不清楚这是什么意思；其次我还想请问：
if (!rclcpp::ok())
{
RCLCPP_ERROR(this->get_logger(), "等待服务的过程中被打断...");
return;
}
这段代码什么时候加上呢？我发现不加上这段代码，crtl+C就无法暂停我的程序
wang2.cpp
#include "rclcpp/rclcpp.hpp"
#include "std_msgs/msg/string.hpp"
#include "std_msgs/msg/u_int32.hpp"
#include "village_interfaces/srv/sell_novel.hpp"
#include <queue>

using std::placeholders::_1;
using std::placeholders::_2;

/*
创建一个类节点，名字叫做SingleDogNode,继承自Node.
*/
class SingleDogNode : public rclcpp::Node
{

public:
// 构造函数,有一个参数为节点名称
SingleDogNode(std::string name) : Node(name)
{
// 打印一句自我介绍
RCLCPP_INFO(this->get_logger(), "大家好，我是单身狗%s.", name.c_str());
// 创建一个订阅者来订阅李四写的小说，通过名字sexy_girl
sub_novel = this->create_subscription<std_msgs::msg::String>("sexy_girl", 10, std::bind(&SingleDogNode::topic_callback, this, _1));
// 创建发布者
pub_money = this->create_publisher<std_msgs::msg::UInt32>("sexy_girl_money", 10);

    sell_novels_callback_group = this->create_callback_group(rclcpp::CallbackGroupType::MutuallyExclusive);

    sell_server = this->create_service<village_interfaces::srv::SellNovel>("sell_novel", std::bind(&SingleDogNode::sell_novel_callback, this, _1, _2),
                                                                            rmw_qos_profile_services_default, sell_novels_callback_group);
}

private:
std::queuestd::string novels_queue;
// 声明一个订阅者（成员变量）,用于订阅小说
rclcpp::Subscription<std_msgs::msg::String>::SharedPtr sub_novel;

// 声明一个发布者（成员变量）,用于给李四钱
rclcpp::Publisher<std_msgs::msg::UInt32>::SharedPtr pub_money;

rclcpp::CallbackGroup::SharedPtr sell_novels_callback_group;

rclcpp::Service<village_interfaces::srv::SellNovel>::SharedPtr sell_server;

// maishu
void sell_novel_callback(const village_interfaces::srv::SellNovel::Request::SharedPtr request,
                        const village_interfaces::srv::SellNovel::Response::SharedPtr response)
{
    RCLCPP_INFO(this->get_logger(), "shoudaole %d", request->money);
    unsigned int num = (int)request->money;

    if(num > novels_queue.size())
    {
        RCLCPP_INFO(this->get_logger(), "%ld<%d", novels_queue.size(), num);

        rclcpp::Rate rate(1);

        while (novels_queue.size() < num)
        {

            if(!rclcpp::ok())
            {
                RCLCPP_ERROR(this->get_logger(), "程序被终止了");
                return ;
            }
            RCLCPP_INFO(this->get_logger(), "%ld", num - novels_queue.size());
            rate.sleep();
        }
    }
    
    RCLCPP_INFO(this->get_logger(), "%ld > %d", novels_queue.size(), num);

    for(int i = 0; i<(int)num; i++)
    {
        response->novels.push_back(novels_queue.front());
        novels_queue.pop();
    }


    
}

// 收到话题数据的回调函数
void topic_callback(const std_msgs::msg::String::SharedPtr msg)
{
    // 新建一张人民币
    std_msgs::msg::UInt32 money;
    money.data = 10;
    // 发送人民币给李四
    pub_money->publish(money);

    novels_queue.push(msg->data);

    RCLCPP_INFO(this->get_logger(), "朕已阅：'%s'，打赏李四：%d 元的稿费", msg->data.c_str(), money.data);
};

};

int main(int argc, char argv)
{
rclcpp::init(argc, argv);
/产生一个Wang2的节点/
auto node = std::make_shared<SingleDogNode>("wang2");
rclcpp::executors::MultiThreadedExecutor executor;
executor.add_node(node);
/ 运行节点，并检测退出信号/
executor.spin();
rclcpp::shutdown();
return 0;
}

zhang3.cpp#include "rclcpp/rclcpp.hpp"
#include "village_interfaces/srv/sell_novel.hpp"

// 提前声明的占位符，留着创建客户端的时候用
using std::placeholders::_1;

/*
创建一个类节点，名字叫做PoorManNode,继承自Node.
*/
class PoorManNode : public rclcpp::Node
{

public:
/* 构造函数 */
PoorManNode(std::string name) : Node(name)
{
// 打印一句自我介绍
RCLCPP_INFO(this->get_logger(), "大家好，我是得了穷病的张三.");
novel_client = this->create_client<village_interfaces::srv::SellNovel>("sell_novel");
}

void buy_novels()
{
    while (!novel_client->wait_for_service(std::chrono::seconds(1)))
    {
        //等待时检测rclcpp的状态
        if (!rclcpp::ok())
        {
            RCLCPP_ERROR(this->get_logger(), "等待服务的过程中被打断...");
            return;
        }
        RCLCPP_INFO(this->get_logger(), "等待服务端上线中");
    }

    auto request = std::make_shared<village_interfaces::srv::SellNovel_Request>();
    request->money = 5;
    novel_client->async_send_request(request, std::bind(&PoorManNode::novels_callback, this, _1));
}

private:
rclcpp::Client<village_interfaces::srv::SellNovel>::SharedPtr novel_client;
void novels_callback(rclcpp::Client<village_interfaces::srv::SellNovel>::SharedFuture response)
{
auto result = response.get();

    RCLCPP_INFO(this->get_logger(), "ok %ld", result->novels.size());

    for(const std::string& novel:result->novels)
    {
        RCLCPP_INFO(this->get_logger(), "%s", novel.c_str());
    }

}

};

/主函数/
int main(int argc, char argv)
{
rclcpp::init(argc, argv);
/产生一个Zhang3的节点/
auto node = std::make_shared<PoorManNode>("zhang3");
node->buy_novels();
/ 运行节点，并检测rclcpp状态/
rclcpp::spin(node);
rclcpp::shutdown();
return 0;
}

小鱼

@3278537301 在按crtl+c之后弹出信息：[INFO] [1713769737.106169624] [rclcpp]: signal_handler(signum=2) 中说：

signal_handler(signum=2)

这个没什么问题，收到了退出信号