36 lines
1.0 KiB
C++
36 lines
1.0 KiB
C++
/*************************************************************************
|
||
> File Name : demo1.cpp
|
||
> Author : TL Song
|
||
> EMail : songtianlun@frytea.com
|
||
> Created Time : Mon Feb 8 08:45:37 2021
|
||
************************************************************************/
|
||
|
||
#include <iostream>
|
||
#include <thread>
|
||
#include <vector>
|
||
#include <mutex>
|
||
#include <chrono>
|
||
#include <stdexcept>
|
||
|
||
int counter = 0;
|
||
void increase(int time) {
|
||
for (int i = 0; i < time; i++) {
|
||
// 当前线程休眠1毫秒
|
||
std::this_thread::sleep_for(std::chrono::milliseconds(1));
|
||
counter++;
|
||
}
|
||
}
|
||
|
||
/*
|
||
* 自增操作"counter++"不是原子操作,而是由多条汇编指令完成的。多个线程对同一个变量进行读写操作就会出现不可预期的操作。
|
||
* 来源:https://zhuanlan.zhihu.com/p/91062516
|
||
*/
|
||
int main(int argc, char** argv) {
|
||
std::thread t1(increase, 10000);
|
||
std::thread t2(increase, 10000);
|
||
t1.join();
|
||
t2.join();
|
||
std::cout << "counter:" << counter << std::endl;
|
||
return 0;
|
||
}
|