c++11 std::mutex

参考:

C++11多线程-mutex(1)

C++11多线程-mutex(2)

C++11 并发指南三(std::mutex 详解)

前两篇博客应该就够了,第三篇作为例子的补充

我目前只看了第一篇的内容...

 

-----------------------------------------------------------笔记---------------------------------------------------------

第一篇博客很适合快速入门,很简短,介绍了std::mutex 和 std::timed_mutex 的基本用法

测试文中的第一个例子调用 mutex.try_lock()

#include <iostream>
#include <thread>
#include <mutex>

void inc(std::mutex &mutex, int loop, int &counter) {
    for (int i = 0; i < loop; i++) {
        mutex.try_lock();
        ++counter;
        mutex.unlock();
    }
}
int main() {
    std::thread threads[5];
    std::mutex mutex;
    int counter = 0;

    for (std::thread &thr: threads) {
        thr = std::thread(inc, std::ref(mutex), 1000, std::ref(counter));
    }
    for (std::thread &thr: threads) {
        thr.join();
    }

    // 输出:5000,如果inc中调用的是try_lock,则此处可能会<5000
    std::cout << counter << std::endl;

    return 0;
}
//: g++ -std=c++11 main.cpp
View Code

第二个例子也很好(std::timed_mutex)

#include <iostream>
#include <thread>
#include <mutex>
#include <chrono>

void run500ms(std::timed_mutex &mutex) {
    auto _500ms = std::chrono::milliseconds(500);
    if (mutex.try_lock_for(_500ms)) {
        std::cout << "获得了锁" << std::endl;
    } else {
        std::cout << "未获得锁" << std::endl;
    }
}
int main() {
    std::timed_mutex mutex;

    mutex.lock();
    std::thread thread(run500ms, std::ref(mutex));
    thread.join();
    mutex.unlock();

    return 0;
}
//输出:未获得锁
View Code

 

 

参考二:

posted @ 2019-07-10 14:17  Johnny、  阅读(1627)  评论(0编辑  收藏  举报