程序代码：

int main(void)
{
    srand((int)time(0));
    int n = rand() % 1000000;

    //int ret = mkdir("n", 0777);
    if(ret < 0)
    {
        printf("....");
    }

    printf("%d\n", n);
    return 0;
}

程序代码：

int main(void)
{
    srand((int)time(0));
    int n = rand() % 1000000;

    //把数字转换成字符串
    char buf[8];
    bzero(buf, 8);

    sprintf(buf, "%d", n);

    int ret = mkdir(buf, 0777);
    if(ret < 0)
    {
        printf("....");
    }

    printf("%d\n", n);
    return 0;
}