1.future线程通信

#include <future>
#include<iostream>
#include <thread>
#include <thread>
#include <string>
using namespace std;

//全局通信变量
promise<string> val;

void main()
{
    auto fun1 = []() 
    {
        //一直等待,获取全局变量的值
        future<string> fu = val.get_future();
        cout << "Waitting" << endl;
        cout <<"获取线程消息" << fu.get() << endl;
    };

    auto fun2 = []()
    {
        system("pause");
        //val.set_value("hello");
        string str1;
        cin >> str1;
        val.set_value(str1);
        system("pause");
    };

    thread t1(fun1);
    thread t2(fun2);
    
    t1.join();
    t2.join();
    system("pause");
}