-#ifdef emacs
-# define my_strftime emacs_strftimeu
-# define ut_argument , ut
-# define ut_argument_spec int ut;
-# define ut_argument_spec_iso , int ut
+/* When compiling this file, GNU applications can #define my_strftime
+ to a symbol (typically nstrftime) to get an extended strftime with
+ extra arguments UT and NS. Emacs is a special case for now, but
+ this Emacs-specific code can be removed once Emacs's config.h
+ defines my_strftime. */
+#if defined emacs && !defined my_strftime
+# define my_strftime nstrftime
+#endif
+
+#ifdef my_strftime
+# define extra_args , ut, ns
+# define extra_args_spec int ut; int ns;
+# define extra_args_spec_iso , int ut, int ns