@node localtime @section @code{localtime} @findex localtime POSIX specification:@* @url{https://pubs.opengroup.org/onlinepubs/9699919799/functions/localtime.html} Gnulib module: localtime Portability problems fixed by Gnulib: @itemize @item On native Windows platforms (mingw, MSVC), this function works incorrectly when the environment variable @code{TZ} has been set by Cygwin. @end itemize Portability problems not fixed by Gnulib: @itemize @item On some platforms, this function loops forever for values near extrema (such as the year @math{-2**31}): Mac OS X 10.6. You can use the @code{time_rz} module to work around the problem. @item On some platforms, this function returns nonsense values for unsupported arguments (like @math{2^56}), rather than failing: FreeBSD 10. @item On some platforms, this function yields incorrect values for timestamps before the year 1: MacOS X 10.5, Solaris 11.3. @item Native Windows platforms (mingw, MSVC) support only a subset of time zones supported by GNU or specified by POSIX@. @xref{tzset}. @end itemize