bool fn_exists (const struct file_handle *);
-FILE *fn_open (const struct file_handle *fn, const char *mode);
-int fn_close (const struct file_handle *fn, FILE *file);
+FILE *fn_fopen (const struct file_handle *, const char *mode);
+int fn_close (const struct file_handle *, FILE *file);
+
+int fn_open (const struct file_handle *, int flags, mode_t mode);
const char * default_output_path (void);