@node gmtime_r
@subsection @code{gmtime_r}
@findex gmtime_r

POSIX specification:@* @url{https://pubs.opengroup.org/onlinepubs/9799919799/functions/gmtime_r.html}

Gnulib module: time_r
@mindex time_r

Portability problems fixed by Gnulib:
@itemize
@item
This function is missing on some platforms:
mingw, MSVC 14.
@item
This function is not declared unless @code{_REENTRANT} is defined,
on some platforms:
HP-UX 11.
@end itemize

Portability problems not fixed by Gnulib:
@itemize
@item
On some platforms, this function yields incorrect values for
timestamps before the year 1:
MacOS X 10.5, Solaris 11.3.
@item
This function sets the field @code{tm_zone} to @code{"GMT"}
instead of @code{"UTC"} on some platforms:
glibc, NetBSD, OpenBSD 7.7, Minix, Cygwin, Android.
@end itemize
