c++多线程之顺序调用类成员函数

#include <iostream>
#include <functional>
#include <future>
using namespace std;

class Foo
{
public:
    Foo();
    ~Foo();

    void first();
    void second();
    void third();

    void printFirst() {
        cout << "first"<<endl;
    }

    void printSecond() {
        cout << "second"<<endl;
    }

    void printThird() {
        cout << "third"<<endl;
    }

private:
    std::promise<void> p1;
    std::promise<void> p2;
};

Foo::Foo()
{
}

Foo::~Foo()
{
}

void Foo::first() {
     printFirst();
    p1.set_value();
}

void Foo::second() {
    p1.get_future().wait();
    printSecond();
    p2.set_value();
}

void Foo::third() {
    p2.get_future().wait();
    printThird();
}



int main()
{
    Foo *fo=new Foo();
    thread t1(&Foo::first,fo);
    thread t2(&Foo::second, fo);
    thread t3(&Foo::third, fo);
    t3.join();
    t2.join();
    t1.join();


    getchar();
    return 0;
}