A Multi-Thread example using C++ 11 thread which meets such case as bgm playing.

multithread.cpp

#include<iostream>
#include<string>
#include<thread>

int timer = 0;
bool timing = false;
std::thread gsub;

void SubTimer()
{
	while (timing)
	{
		_sleep(1000);
		timer++;
		printf("\r%2d", timer);
	}
}

void TimerStart()
{
	timing = true;
	gsub = std::thread(SubTimer);
}

void TimerStop()
{
	timing = false;
	if (gsub.joinable())gsub.join();
}

void TimerReset()
{
	timer = 0;
}

int main()
{
	std::string uinput;
	do {
		std::cout << "1=开始 2=暂停 3=重置 q=退出：";
		std::cin >> uinput;
		if (uinput == "1")TimerStart();
		if (uinput == "2")TimerStop();
		if (uinput == "3")TimerReset();
	} while (uinput != "q");
	TimerStop();
	return 0;
}