couldn't kill node through rosnode kill with moditied (rosnode kill)XMLRPC callback

edit

trying to copy the code from here

https://answers.ros.org/question/2765...

here is my code,ctrl + c just work fine:

sig_atomic_t volatile g_request_shutdown = 0;
// Replacement SIGINT handler
void mySigIntHandler(int sig) {
    ROS_WARN("Shutdown request received. Reason: SIGINT");
    g_request_shutdown = 1;
    ros::shutdown();
}

// Replacement "shutdown" XMLRPC callback
void shutdownCallback(XmlRpc::XmlRpcValue& params,
                      XmlRpc::XmlRpcValue& result) {
    int num_params = 0;
    if (params.getType() == XmlRpc::XmlRpcValue::TypeArray)
        num_params = params.size();
    if (num_params > 1) {
        std::string reason = params[1];
        ROS_WARN("Shutdown request received. Reason: [%s]", reason.c_str());
        ros::shutdown();
        g_request_shutdown = 1;  // Set flag
    }

    result = ros::xmlrpc::responseInt(1, "", 0);
}

int main(int argc, char** argv) {
    ros::init(argc, argv, "robot_decision_node",
          ros::init_options::NoSigintHandler);

    signal(SIGINT, mySigIntHandler);
    // Override XMLRPC shutdown
    ros::XMLRPCManager::instance()->unbind("shutdown");
    ros::XMLRPCManager::instance()->bind("shutdown", shutdownCallback);
    Decision d;
    d.Init();
    ros::Rate loopRate(10);
    while (!g_request_shutdown) {
        ros::spinOnce();
    }
    ROS_INFO("after spin");
    ros::shutdown();
    return 0;
}

then i got another try, changing from spinOnce() to ros::spin(), but still, ctrl + c works fine ,but rosnode kill failed.here is the new code

sig_atomic_t volatile g_request_shutdown = 0;
// Replacement SIGINT handler
void mySigIntHandler(int sig) {
    ROS_WARN("Shutdown request received. Reason: SIGINT");
    g_request_shutdown = 1;
    ros::shutdown();
}

// Replacement "shutdown" XMLRPC callback
void shutdownCallback(XmlRpc::XmlRpcValue& params,
                      XmlRpc::XmlRpcValue& result) {
    int num_params = 0;
    if (params.getType() == XmlRpc::XmlRpcValue::TypeArray)
        num_params = params.size();
    if (num_params > 1) {
        std::string reason = params[1];
        ROS_WARN("Shutdown request received. Reason: [%s]", reason.c_str());
        ros::shutdown();
        g_request_shutdown = 1;  // Set flag
    }

    result = ros::xmlrpc::responseInt(1, "", 0);
}

int main(int argc, char** argv) {
    ros::init(argc, argv, "robot_decision_node",
          ros::init_options::NoSigintHandler);

    signal(SIGINT, mySigIntHandler);
    // Override XMLRPC shutdown
    ros::XMLRPCManager::instance()->unbind("shutdown");
    ros::XMLRPCManager::instance()->bind("shutdown", shutdownCallback);
    Decision d;
    d.Init();
    ros::spin(); // ***change here!!!!***
    ROS_INFO("after spin");
    ros::shutdown();
    return 0;
}

now with commenting the ros::shutdown() in call back ,it's worked fine, but why????

sig_atomic_t volatile g_request_shutdown = 0;
// Replacement SIGINT handler
void mySigIntHandler(int sig) {
    ROS_WARN("Shutdown request received. Reason: SIGINT");
    g_request_shutdown = 1;
    // ros::shutdown();  // change here!!!!!
}

// Replacement "shutdown" XMLRPC callback
void shutdownCallback(XmlRpc::XmlRpcValue& params,
                      XmlRpc::XmlRpcValue& result) {
    int num_params = 0;
    if (params.getType() == XmlRpc::XmlRpcValue::TypeArray)
        num_params = params.size();
    if (num_params > 1) {
        std::string reason = params[1];
        ROS_WARN("Shutdown request received. Reason: [%s]", reason.c_str());
        // ros::shutdown();  // change here!!!!!
        g_request_shutdown = 1;  // Set flag
    }

    result = ros::xmlrpc::responseInt(1, "", 0);
}

int main(int argc, char** argv) {
    ros::init(argc, argv, "robot_decision_node",
          ros::init_options::NoSigintHandler);

    signal(SIGINT, mySigIntHandler);
    // Override XMLRPC shutdown
    ros::XMLRPCManager::instance()->unbind("shutdown");
    ros::XMLRPCManager::instance()->bind("shutdown", shutdownCallback);
    Decision d;
    d.Init();
    ros::Rate loopRate(10);
    while (!g_request_shutdown) {
        ros::spinOnce();
    }
    ROS_INFO("after spin");
    ros::shutdown();
    return 0;
}