C++線程同步之事件（生產者與消費者問題）

#include <windows.h>
#include <stdio.h>

HANDLE g_hSet = NULL;
HANDLE g_hClear = NULL;
HANDLE hThread[2] = { NULL };
int g_Max = 10;
int g_Number = 0;

// 生產者線程
DWORD WINAPI ThreadProc1(LPVOID lpParameter)
{
    for (int i = 0; i < g_Max; i++)
    {
        WaitForSingleObject(g_hSet, INFINITE);
        g_Number = 1;
        DWORD id = GetCurrentThreadId();
        printf("生產者%d將數據%d放入緩衝區！\n", id, g_Number);
        SetEvent(g_hClear);
    }
    return 0;
}

// 消費者線程
DWORD WINAPI ThreadProc2(LPVOID lpParameter)
{
    for (int i = 0; i < g_Max; i++)
    {
        WaitForSingleObject(g_hClear, INFINITE);
        g_Number = 0;
        DWORD id = GetCurrentThreadId();
        printf("---消費者%d將數據%d放入緩衝區！\n", id, g_Number);
        SetEvent(g_hSet);
    }
    return 0;
}

int main()
{
    g_hSet = ::CreateEvent(NULL, FALSE, TRUE, NULL);
    g_hClear = ::CreateEvent(NULL, FALSE, FALSE, NULL);
    hThread[0] = CreateThread(0, 0, ThreadProc1, 0, 0, 0);
    hThread[1] = CreateThread(0, 0, ThreadProc2, 0, 0, 0);
    WaitForMultipleObjects(2, hThread, TRUE, -1);
    CloseHandle(hThread[0]);
    CloseHandle(hThread[1]);
    CloseHandle(g_hClear);
    CloseHandle(g_hSet);
    getchar();
    return 0;
}

臨界區與互斥體是不能解決線程同步問題的，只能解決互斥問題，可是事件既能夠解決互斥問題，又能夠解決線程同步問題。