c ++多线程问题

Question

所以我一直在尝试将多线程实现到我的程序中（对于macOS）但是我遇到了一些问题，第一个是当我尝试退出主线程赢得的线程时。继续运行，我的第二个问题是我创建的每个线程我的CPU使用率上升了~100％，这是我降低CPU使用率的最佳方式吗？
干杯

void *KeepListening(void *commandid) {

    long tid = (long)commandid;

    if(tid != 1)
        return 0;

    for(int i = 0; killthread == false ; i++) {

        if(i % WhenToSleep == 1)
            sleep(10);



        if(i % waittime == 1) {

            abc = con->post(listento, "request=abc");
            xyz = con->post(listento, "request=xyz");
            sleep(1);

            if(abc == "true") {
                threadscreated = false;
            } else if(abc == "false") {
                killthread = true;
            }
        }



    }

    cout << "Killing thread\n";
    shouldcreate = true;
    pthread_exit(NULL);

}


void Listen() {

    pthread_t threads[1];
    int rc;

    for(int i = 0;  ;i++) {

        if(i % WhenToSleep == 1)
            sleep(10);

        if(i % waittime == 1) {

            abc = con->post(listento, "request=abc");
            xyz = con->post(listento, "request=xyz");
            sleep(1);

            if(abc == "true") {
                threadscreated = false;
            } else if(abc == "false") {
                killthread = true;
            }

        }



        if(!threadscreated && shouldcreate) {

            rc = pthread_create(&threads[0], NULL, HandleCommands, (void *)1);
            sleep(1);

            threadscreated  = true;
            shouldcreate    = false;

            cout << "Threads Created\n";

            sleep(5);

        }

    }


    pthread_exit(NULL);

}