在使用pthread_create创建的线程之间读写管道时，是否需要关闭fds？

Question

There is a client server application I am working on. Below is the code from client side.

pipe_input , pipe_output are shared variables.

        int fds[2];
            if (pipe(fds)) {
                        printf("pipe creation failed");
                    }  else {
                        pipe_input = fds[0];
                        pipe_output = fds[1];
                        reader_thread_created = true;
                        r = pthread_create(&reader_thread_id,0,reader_thread,this);
                        }


 void* reader_thread(void *input)
    {
    unsigned char id;
        int n;
        while (1) {

            n = read(pipe_input , &id, 1);
            if (1 == n) {
                //process
            }if ((n < 0) ) {
                printf("ERROR: read from pipe failed");
                break;
            }
        }
        printf("reader thread stop");
        return 0;
    }

There is a writer thread also which writes data on event change from server.

void notify_client_on_event_change(char id)
{
    int n;
    n= write(pipe_output, &id, 1);
    printf("message written to pipe done ");
}

My question is do I need to close the write end in reader thread and read end in case of writer thread. In the destructor, I am waiting for reader thread to exit but sometimes it doesn't exit from reader thread.

Answer 1

[...] do i need to close the write end in reader thread and read end in case of writer thread[?]

As those fds " are shared ", closing them in one thread would close them for all threads. That is not what you want, I suspect.