VS2015 多线程同步 Event

在《VC++深入详解》多线程源码上做了修订，因为若在VS2015上跑原书代码，效果并不明显，可能很多人从而对书本产生质疑。

CPU从以前的伪多线程进入真正的多线程时代，这些是书本作者“”孙鑫”没考虑到的。

上代码，原书开了2个线程，效果远远不如4个线程明显

SetEvent:  让事件有信号，这样WaitForSingleObject就不会阻塞线程

ResetEvent;让事件无信号，WaitForSingleObject会阻塞线程

CreateEvent:

第一个参数:安全属性，不用管设为NULL

第二个参数:是否手动Reset   如果是TRUE  那么WaitForSingleObject后事件保持原有受信状态， 如果是FALSE那么WaitForSingleObject后事件变成无信号状态

第三个参数:初始化事件状态，TRUE就能受信，FALSE就无信号

第四个参数：事件名称，可选，可以设为NULL

#include "stdafx.h"
#include 
#include 

static HANDLE s_hEvent;
static int s_tickets = 100;

DWORD WINAPI  ThreadFun1(LPVOID lpParam)
{
	while (true)
	{
		WaitForSingleObject(s_hEvent, INFINITE); //获得事件控制权
		if (s_tickets > 0)
		{
			Sleep(1);
			std::cout << "--1 sell ticket : " << s_tickets-- << std::endl;
			SetEvent(s_hEvent); //这里让事件受信，让其它线程可以销售ticket
		}
		else
			break;
	}
	return 0;
}

DWORD WINAPI  ThreadFun2(LPVOID lpParam)
{
	while (true)
	{
		WaitForSingleObject(s_hEvent, INFINITE);
		if (s_tickets > 0)
		{
			Sleep(1);
			std::cout << "--2 sell ticket : " << s_tickets-- << std::endl;
			SetEvent(s_hEvent);
		}
		else
			break;
	}
	return 0;
}

DWORD WINAPI  ThreadFun3(LPVOID lpParam)
{
	while (true)
	{
		WaitForSingleObject(s_hEvent, INFINITE);
		if (s_tickets > 0)
		{
			Sleep(1);
			std::cout << "--3 sell ticket : " << s_tickets-- << std::endl;
			SetEvent(s_hEvent);
		}
		else
			break;
	}
	return 0;
}

DWORD WINAPI  ThreadFun4(LPVOID lpParam)
{
	while (true)
	{
		WaitForSingleObject(s_hEvent, INFINITE);
		if (s_tickets > 0)
		{
			Sleep(1);
			std::cout << "--4 sell ticket : " << s_tickets-- << std::endl;
			SetEvent(s_hEvent);
		}
		else
			break;
	}
	return 0;
}

int main()
{
	HANDLE hThread1;
	HANDLE hThread2;
	HANDLE hThread3;
	HANDLE hThread4;

							   
	s_hEvent = CreateEvent(NULL, FALSE, TRUE, _T("EventTest"))

	hThread1 = CreateThread(NULL, 0, ThreadFun1, NULL, 0, NULL);
	hThread2 = CreateThread(NULL, 0, ThreadFun2, NULL, 0, NULL);
	hThread3 = CreateThread(NULL, 0, ThreadFun3, NULL, 0, NULL);
	hThread4 = CreateThread(NULL, 0, ThreadFun4, NULL, 0, NULL);
	CloseHandle(hThread1); //这里不用对线程操作，所以可以先把句柄关闭，不然会产生内存泄漏，句柄的实质是结构体指针。
	CloseHandle(hThread2);
	CloseHandle(hThread3);
	CloseHandle(hThread4);

	Sleep(4000);
	CloseHandle(s_hEvent);

	system("pause");
	return 0;
}