VS2010 多线程编程

1、多线程测试实例：

　　此时在多核CPU下，主线程和子线程可同时运行；时间片是怎么分配的呢？感觉好乱呢？

#include <windows.h>
#include <iostream>
#include <stdlib.h>
using namespace std;

DWORD WINAPI MyThreadProc1(LPVOID lpParameter);
DWORD WINAPI MyThreadProc2(LPVOID lpParameter);
int index = 0;
int i = 0 , y = 0;
int main()
{
    HANDLE handle1,handle2;
    handle1 = CreateThread(NULL,0,MyThreadProc1,NULL,0,NULL);
    handle2 = CreateThread(NULL,0,MyThreadProc2,NULL,0,NULL);

    if(NULL == handle1)
    {
        cout<<"Create Thread failed !"<<endl;
        return -1;
    }
    if(NULL == handle2)
    {
        cout<<"Create Thread failed !"<<endl;
        return -1;
    }

    CloseHandle(handle1);
    CloseHandle(handle2);

    cout<<"The Main Thread is Running !"<<endl;

    system("PAUSE");
    return 0;
}
DWORD WINAPI MyThreadProc1(LPVOID lpParameter)
{

    cout<<"The MyThreadProc1 is Running !"<<endl;

    return 0;
}
DWORD WINAPI MyThreadProc2(LPVOID lpParameter)
{
    
    cout<<"The MyThreadProc2 is Running ! "<<endl;
    return 0;
}

 

2、线程同步：

 使用互斥对象实现线程同步，主要用到的函数：

　　CreateMutex();  其第二个参数若设为TRUE，则主线程拥有一个CPU内核；创建带名字的互斥对象，根据第三个参数可判断互斥对象已存在；

　　ReleaseMutex();  若线程运行完成后，会自动释放互斥对象；

　　WaitForSingleObject();

（1）没有同步的实例：

#include <windows.h>
#include <iostream>
#include <stdlib.h>
using namespace std;


DWORD WINAPI MyThreadProc1(LPVOID lpParameter);
DWORD WINAPI MyThreadProc2(LPVOID lpParameter);
int index = 100;

int main()
{
	HANDLE handle1,handle2;
	handle1 = CreateThread(NULL,0,MyThreadProc1,NULL,0,NULL);
	handle2 = CreateThread(NULL,0,MyThreadProc2,NULL,0,NULL);

	if(NULL == handle1)
	{
		cout<<"Create Thread failed !"<<endl;
		return -1;
	}
	if(NULL == handle2)
	{
		cout<<"Create Thread failed !"<<endl;
		return -1;
	}

	CloseHandle(handle1);
	CloseHandle(handle2);

	Sleep(2000);
	system("PAUSE");
	return 0;
}
DWORD WINAPI MyThreadProc1(LPVOID lpParameter)
{
	while(true)
	{
		if(index > 0)
		{
			Sleep(1);
			cout<<"The Index1 Number is : "<<index--<<endl;
		}
		else 
			break;
	}
	return 0;
}
DWORD WINAPI MyThreadProc2(LPVOID lpParameter)
{
	while(true)
	{
		if(index > 0)
		{
			Sleep(1);
			cout<<"The Index2 Number is : "<<index--<<endl;
		}
		else 
			break;
	}
	return 0;
}

　（2）互斥对象实现多线程同步：根据个人电脑CPU而异，此代码中main()占有一个CPU内核；且没有使用ReleaseMutex()释放所占CPU；

#include <windows.h>
#include <iostream>
#include <stdlib.h>
using namespace std;


DWORD WINAPI MyThreadProc1(LPVOID lpParameter);
DWORD WINAPI MyThreadProc2(LPVOID lpParameter);
DWORD WINAPI MyThreadProc3(LPVOID lpParameter);

int index = 100;
HANDLE hMutex;

int main()
{
	HANDLE handle1,handle2,handle3;
	handle1 = CreateThread(NULL,0,MyThreadProc1,NULL,0,NULL);
	handle2 = CreateThread(NULL,0,MyThreadProc2,NULL,0,NULL);
	handle3 = CreateThread(NULL,0,MyThreadProc3,NULL,0,NULL);

	if(NULL == handle1)
	{
		cout<<"Create Thread failed !"<<endl;
		return -1;
	}
	if(NULL == handle2)
	{
		cout<<"Create Thread failed !"<<endl;
		return -1;
	}
	if(NULL == handle3)
	{
		cout<<"Create Thread failed !"<<endl;
		return -1;
	}

	CloseHandle(handle1);
	CloseHandle(handle2);
	CloseHandle(handle3);

	hMutex = CreateMutex(NULL,TRUE,NULL);

	Sleep(2000);
	system("PAUSE");
	return 0;
}
DWORD WINAPI MyThreadProc1(LPVOID lpParameter)
{
	while(true)
	{
		WaitForSingleObject(hMutex,INFINITE);
		if(index > 0)
		{
			Sleep(1);
			cout<<"The Index1 Number is : "<<index--<<endl;
		}
		else 
			break;
	}
	return 0;
}
DWORD WINAPI MyThreadProc2(LPVOID lpParameter)
{
	while(true)
	{
		WaitForSingleObject(hMutex,INFINITE);
		if(index > 0)
		{
			Sleep(1);
			cout<<"The Index2 Number is : "<<index--<<endl;
		}
		else 
			break;
	}
	return 0;
}

DWORD WINAPI MyThreadProc3(LPVOID lpParameter)
{
	while(true)
	{
		WaitForSingleObject(hMutex,INFINITE);
		if(index > 0)
		{
			Sleep(1);
			cout<<"The Index3 Number is : "<<index--<<endl;
		}
		else 
			break;
	}
	return 0;
}