Uso RAII espera para que el hilo se completa

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

struct func
{
	int iNum;
	func(int &i):iNum(i)
	{

	}

	void operator()()
	{
		for (int i = 0; i < 1000; i++)
		{
			cout << "线程执行..." << this_thread::get_id() << "    i=" << i << endl;
		}
	}

};

class thread_guard
{
private:
	std::thread& t;
public:
	explicit thread_guard(std::thread& th):t(th){}

	~thread_guard()
	{
		if (t.joinable())
		{
			t.join();
		}
	}

	thread_guard(const thread_guard&) = delete;
	thread_guard& operator=(const thread_guard&) = delete;
};

int main()
{

	int local_num = 0;
	func my_func(local_num);  //局部变量给线程,特别需要注意，非常危险，只有保证局部变量有效时线程执行完毕
	std::thread t(my_func);
	
	thread_guard g(t);	// 当此main函数退出时，自动调用thread_guard析构函数，将使线程t执行完毕

	return 0;
}