-size_t nstrftime (char *, size_t, char const *, struct tm const *, int, int);
+/* Just like strftime, but with two more arguments:
+ POSIX requires that strftime use the local timezone information.
+ When __UTC is nonzero and tm->tm_zone is NULL or the empty string,
+ use UTC instead. Use __NS as the number of nanoseconds in the
+ %N directive. */
+size_t nstrftime (char *, size_t, char const *, struct tm const *,
+ int __utc, int __ns);