-void fio_file_reset(struct thread_data *, struct fio_file *);
-int fio_files_done(struct thread_data *);
+extern void fio_file_reset(struct thread_data *, struct fio_file *);
+extern bool fio_files_done(struct thread_data *);
+extern bool exists_and_not_regfile(const char *);
+extern int fio_set_directio(struct thread_data *, struct fio_file *);