Question

我正在试图弄清楚两个相关进程之间的管道通信是如何工作的，所以我写了这个简单的C程序。

#define  READ   0
#define  WRITE  1

char*  phrase = "This is a message!!!";
char*  phrase2 = "This is a second message!!!";

char buffer[100];

void sigpipe_h(int sig0){       //SIGPIPE handler
    printf("Ricevuto SIGPIPE\n");
    signal(SIGPIPE, sigpipe_h);
}

int main()
{
int fd[2], bytesRead, bytesRead2;
signal(SIGPIPE, sigpipe_h);

pipe(fd);

pid_t pid = fork();

if(pid == 0){   //child
    write(fd[WRITE], phrase, strlen(phrase)+1);     //write
    sleep(2);
    write(fd[WRITE], phrase2, strlen(phrase2)+1);//i'm writing for the second time

    sleep(2);
    close(fd[WRITE]);   //write side closed
}
else {          //parent
    bytesRead = read(fd[READ], buffer, 100); //receive message
    printf("The process %d has received %d bytes: %s \n", getpid(), bytesRead, buffer );
    close(fd[READ]);   //read side closed

    sleep(4);

}

return 0;


}

我创建了一个管道，孩子在上面写了一些东西，父母读取了消息并关闭了读取侧管道。到目前为止它工作得很好，但是当我尝试发送第二条消息时，管道在读取端关闭，它应该引发由我的sigpipe_h函数处理的SIGPIPE信号，不是吗？为什么不发生？我哪里错了？

感谢您的帮助。

SIGPIPE信号处理

0 个答案: