36 lines
1.0 KiB
C++
36 lines
1.0 KiB
C++
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/*************************************************************************
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> File Name : demo1.cpp
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> Author : TL Song
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> EMail : songtianlun@frytea.com
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> Created Time : Mon Feb 8 08:45:37 2021
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************************************************************************/
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#include <iostream>
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#include <thread>
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#include <vector>
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#include <mutex>
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#include <chrono>
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#include <stdexcept>
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int counter = 0;
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void increase(int time) {
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for (int i = 0; i < time; i++) {
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// 当前线程休眠1毫秒
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std::this_thread::sleep_for(std::chrono::milliseconds(1));
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counter++;
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}
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}
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/*
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* 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。
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* 来源：https://zhuanlan.zhihu.com/p/91062516
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*/
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int main(int argc, char** argv) {
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std::thread t1(increase, 10000);
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std::thread t2(increase, 10000);
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t1.join();
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t2.join();
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std::cout << "counter:" << counter << std::endl;
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return 0;
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}
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