[C++知识库]c++ builder windows 线程之事件(event)

//本文描述的事件，是线程语境的事件(event)

//本文在c++ buider 10.3 调试通过。

#include<windows.h>
#include<stdio.h>
int product_buffer = 3;
int product_num = 2;

//定义事件句柄，由于在多个线程中使用，需定义为全局变量
HANDLE hde_Producer,hde_Consumer;

DWORD WINAPI Producer(LPVOID lpParameter)
{? ?while(1)
?? ?{? ?//等待生产者线程的事件信号
?? ??? ?WaitForSingleObject(hde_Producer,INFINITE);

?? ??? ?product_num++;
?? ??? ?printf("producer: produce 1, %d in buffer\n", product_num);

?? ??? ?Sleep(1000);

?? ??? ?//将消费者进程的事件置为Signaled
?? ??? ?SetEvent(hde_Consumer);
?? ?}
?? ?return 0;
}

DWORD WINAPI Consumer(LPVOID lpParameter)
{? ?while(1)
?? ?{? ?//等待事件信号
?? ??? ?WaitForSingleObject(hde_Consumer,INFINITE);
?? ??? ?product_num--;
?? ??? ?if (product_num <= 1){
?? ??? ??? ?printf("consumer: consume 1, only %d left in buffer, alert!\n",product_num);
?? ??? ?}else{
?? ??? ??? ?printf("consumer: consume 1, %d left in buffer\n",product_num);
?? ??? ?}
?? ??? ?Sleep(1000);
?? ??? ?//将生产者进程的事件置为Signaled
?? ??? ?SetEvent(hde_Producer);
?? ?}

?? ?return 0;
}

int main()

{? ? HANDLE ThreadHandles[2];

?? ?//创建两个事件，分别用于触发生产者进程和消费者进程。
?? ?//生产者进程的事件的初始状态设置为有信号，消费者为无信号。两个事件都自动复位
?? ?hde_Producer = CreateEvent(NULL,FALSE,TRUE,NULL);
?? ?hde_Consumer = CreateEvent(NULL,FALSE,FALSE,NULL);

?? ?ThreadHandles[0] = CreateThread(
?? ??? ?NULL,
?? ??? ?0,
?? ??? ?Producer,
?? ??? ?NULL,
?? ??? ?0,
?? ??? ?NULL
?? ?);

?? ?ThreadHandles[1] = CreateThread(
?? ??? ?NULL,
?? ??? ?0,
?? ??? ?Consumer,
?? ??? ?NULL,
?? ??? ?0,
?? ??? ?NULL
?? ?);

?? ?WaitForMultipleObjects(2,ThreadHandles,TRUE,INFINITE);
?? ?return 0;
}