火车票线程同步（一）互斥体实现

*注:（此代码必背）

##

#include <windows.h>
#include <iostream>

int tickets = 100;
HANDLE hMutex;

DWORD WINAPI FunProc1(LPVOID param)
{
    while (TRUE)
    {
        WaitForSingleObject(hMutex, INFINITE);
        if (tickets > 0)
        {
            std::cout << "thread1 sell ticket:" << tickets-- << std::endl;
        }
        else
            break;
        ReleaseMutex(hMutex);
    }
    return 0;
}
DWORD WINAPI FunProc2(LPVOID param)
{
    while (TRUE)
    {
        WaitForSingleObject(hMutex, INFINITE);
        if (tickets > 0)
        {
            std::cout << "thread2 sell ticket:" << tickets-- << std::endl;
        }
        else
            break;
        ReleaseMutex(hMutex);
    }
    return 0;
}

int main()
{
    HANDLE hThread1, hThread2;
    hMutex = CreateMutex(NULL, FALSE, NULL);//创建互斥体的线程（也就是此主线程）不拥有
    //互斥对象，操作系统会将计数置为0，设为有信号状态。
    hThread1 = CreateThread(NULL, 0, FunProc1, NULL, 0, NULL);
    hThread2 = CreateThread(NULL, 0, FunProc2, NULL, 0, NULL);
    CloseHandle(hThread1);
    CloseHandle(hThread2);
    Sleep(4000);
}

注释：

在创建互斥对象时，第二个参数为FALSE值，表明当前没有线程拥有这个互斥对象，于是操作系统就会将该互斥对象设置为有信号状态。