int real_munmap(void *addr, size_t length);
int real_read(int fd, void *buf, size_t count);
int real_ioctl(int fd, int request, void *argp);
int real_munmap(void *addr, size_t length);
int real_read(int fd, void *buf, size_t count);
int real_ioctl(int fd, int request, void *argp);