-#if __STDC__
-# undef __P
-# define __P(args) args
-#else
-# define __P(args) ()
-#endif
+#if ! defined PATH_CONCAT_H_
+# define PATH_CONCAT_H_
+
+# ifndef PARAMS
+# if defined PROTOTYPES || (defined __STDC__ && __STDC__)
+# define PARAMS(Args) Args
+# else
+# define PARAMS(Args) ()
+# endif
+# endif
char *
-path_concat _P ((const char *dir, const char *base, char **base_in_result));
+path_concat PARAMS ((const char *dir, const char *base, char **base_in_result));
+
+#endif