-extern void *os_open_dir(char *dir, int *err_out);
-extern int os_seek_dir(void *stream, unsigned long long pos);
-extern int os_read_dir(void *stream, unsigned long long *ino_out,
- char **name_out);
-extern int os_tell_dir(void *stream);
-extern int os_close_dir(void *stream);
-extern int os_remove_file(const char *file);
-extern int os_move_file(const char *from, const char *to);
-extern int os_truncate_file(const char *file, unsigned long long len);
-extern int os_truncate_fd(int fd, unsigned long long len);