c++11多线程学习笔记之二 mutex使用

// 1111111.cpp : 定义控制台应用程序的入口点。
//

#include "stdafx.h"
#include <iostream>
#include <thread>
#include <mutex>         

int gcounter = 0;
std::mutex gmtx;    
std::mutex gmtxOutput;

void Increases() {
	for (int i = 0; i<10000; ++i) {
		if (gmtx.try_lock()) {   // only increase if currently not locked:
			++gcounter;
			gmtx.unlock();
		}
		else{
			gmtxOutput.lock();
			std::cout << "try lock failed" << std::endl;
			gmtxOutput.unlock();
		}
	}
}

int _tmain(int argc, _TCHAR* argv[]) {
	std::thread threads[10];
	for (int i = 0; i<10; ++i)
		threads[i] = std::thread(Increases);

	for (auto& th : threads) 
		th.join();
	std::cout << "counter is " << gcounter << std::endl;

	return 0;
}