多线程用Event控制流程

#define N_OBJECTS 26

HANDLE hEvents[N_OBJECTS];
HANDLE hThreads[N_OBJECTS];

DWORD WINAPI PrintChar(LPVOID lpParam)
{
    int i = (int)lpParam;
    printf("current thread id = %d, ready
", i);
    Sleep(rand() % 100);
    WaitForSingleObject(hEvents[i], -1);
    printf("%c, ", i+'A');
    Sleep(rand() % 300);
    SetEvent(hEvents[i+1]);
    return 0;
}


int main()
{
    srand(time(nullptr));
    for (int i = 0; i < N_OBJECTS; i++)
    {
        hEvents[i] = CreateEvent(nullptr, false, false, nullptr);
        if (!hEvents[i])
        {
            printf("CreateEvent %d falied
", i);
            return 1;
        }
    }

    for (int i = 0; i < N_OBJECTS; i++)
    {
        hThreads[i] = CreateThread(nullptr, 0, PrintChar, (LPVOID)i, 0, nullptr);
        if (!hThreads[i])
        {
            printf("CreateThread %d falied
", i);
            return 2;
        }
    }
    SetEvent(hEvents[0]);
    
    WaitForMultipleObjects(N_OBJECTS, hThreads, true, INFINITE);

    printf("

Bye!
");
    return 0;
}

Output:

current thread id = 0, ready
current thread id = 1, ready
current thread id = 2, ready
current thread id = 3, ready
current thread id = 4, ready
current thread id = 5, ready
current thread id = 6, ready
current thread id = 7, ready
current thread id = 8, ready
current thread id = 9, ready
current thread id = 10, ready
current thread id = 11, ready
current thread id = 12, ready
current thread id = 13, ready
current thread id = 14, ready
current thread id = 15, ready
current thread id = 16, ready
current thread id = 17, ready
current thread id = 19, ready
current thread id = 18, ready
current thread id = 20, ready
current thread id = 21, ready
current thread id = 22, ready
current thread id = 23, ready
current thread id = 24, ready
current thread id = 25, ready
A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V, W, X, Y, Z,

Bye!