【linux笔记1.2】在多线程开发中尽量少用sleep的解决方案

方案1：线程挂起与恢复

代码示例[1]

#include <unistd.h>
#include <pthread.h>

static pthread_mutex_t mutex;
static pthread_cond_t cond;
static int flag = 0;

void srpthread_init()
{
    pthread_mutex_init(&mutex,NULL);
    pthread_cond_init(&cond,NULL);
}

void srpthread_suspend()
{
    pthread_mutex_lock(&mutex);
    flag--;
    pthread_mutex_unlock(&mutex);
}


void srpthread_resume()
{
    pthread_mutex_lock(&mutex);
    flag++;
    pthread_cond_signal(&cond);
    pthread_mutex_unlock(&mutex);
}

void *thread_run()
{
    while(1)
    {
        pthread_mutex_lock(&mutex);
        while(flag<=0)
        {
            pthread_cond_wait(&cond,&mutex);
        }

        pthread_mutex_unlock(&mutex);

        //actual work
        printf("i am running!\n");
    }

}

int main(int argc,char *argv[])
{
    char ch;
    pthread_t p1;
    srpthread_init();
    pthread_create(&p1,NULL,(void *)thread_run,NULL);

    while(1)
    {
        scanf("%c",&ch);
        switch(ch)
        {
            case 's':
                srpthread_suspend();
                break;
            case 'r':
                srpthread_resume();
                break;
            default:
                break;
        }
    }
#if 0
    printf("1111\n");
    srpthread_resume();
    printf("2222\n");
    sleep(3);
    printf("3333\n");
    srpthread_suspend();
    printf("4444\n");
#endif
    return 1;
}

方案2：用select让线程沉睡

代码示例[2]

void thread_sleep(unsigned long sleepSecond)
{
#if (APP_USE_SYS == APP_SYS_LINUX)
    timeval t_timeval;
    t_timeval.tv_sec = (sleepSecond / 1000);
    t_timeval.tv_usec = (sleepSecond % 1000);
    select(0, NULL, NULL, NULL, &t_timeval);
#else
    Sleep(sleepSecond);
#endif
    return;
}

参考文献

[1] https://blog.csdn.net/honghuzhilangzixin/article/details/7908236
[2] https://bbs.csdn.net/wap/topics/360129370