+# define VALID_BACKUP_TYPE(Type) \
+ ((unsigned int) (Type) <= numbered_backups)
+
+extern char const *simple_backup_suffix;
+
+char *find_backup_file_name (char const *, enum backup_type);
+enum backup_type get_version (char const *context, char const *arg);
+enum backup_type xget_version (char const *context, char const *arg);
+void addext (char *, char const *, int);
+
+
+# ifdef __cplusplus
+}
+# endif