void fuse_do_write(fd)
{
    fflush(stdout);
    puts("-----------------------");
    puts("[+] start do_write");

    // splice read requset from pipe
    puts("[+] create pipe");
    int pfd[2], ret;
    ret = pipe(pfd);
    if (ret < 0)
        fatal("pipe");
    size_t bufsize = getpagesize() + 0x1000;
    ret = splice(fd, NULL, pfd[1], NULL, bufsize, 0);
    if (ret < 0)
        fatal("splice");

    // 通过splice读取头部；
    struct fuse_in_header in;
    ret = read(pfd[0], &in, sizeof(struct fuse_in_header));
    if (ret < 0)
        fatal("read head");
    fuse_show_req_head(&in);

    puts("[+] send reply finish write");//回复write请求
    struct fuse_write_out outarg;
    outarg.size = 1;
    outarg.padding = 0;
    printf("unique: %d\n", in.unique);
    fuse_send_reply(fd, &outarg, sizeof(outarg), 0, in.unique);

    // 阻塞等待子进程write结束
    int t = 0;
    do
    {
        fflush(stdout);
        puts("[+] input 1 to contine, other to block");
        scanf("%d", &t);
        puts("[+] ...");

    } while (t != 1);

    struct fuse_write_in inarg;
    struct fuse_bufvec bufv;
    ret = read(pfd[0], &inarg, sizeof(struct fuse_write_in));
    if (ret < 0)
        fatal("read write in");

    printf("[+] write in:\n");
    printf("\tfh:\t%lld\n", inarg.fh);
    printf("\toffset:\t%lld\n", inarg.offset);
    printf("\tsize:\t%d\n", inarg.size);
    printf("\twrite_flags:\t%d\n", inarg.write_flags);
    printf("\tlock_owner:\t%llx\n", inarg.lock_owner);
    printf("\tflags:\t%d\n", inarg.flags);
    printf("\tpadding:\t%d\n", inarg.padding);

    ret = read(pfd[0], &bufv, sizeof(bufv)); //客户端write结束以后再读取page
    printf("bufv:\t%s\n", (char *)&bufv);

    puts("[+] end do_write");
    close(pfd[0]);
    close(pfd[1]);
}