1@node tzset 2@section @code{tzset} 3@findex tzset 4 5POSIX specification:@* @url{https://pubs.opengroup.org/onlinepubs/9699919799/functions/tzset.html} 6 7Gnulib module: tzset 8 9Portability problems fixed by Gnulib: 10@itemize 11@item 12On native Windows platforms (mingw, MSVC), this function works incorrectly 13when the environment variable @code{TZ} has been set by Cygwin. 14@end itemize 15 16Portability problems not fixed by Gnulib: 17@itemize 18@item 19Native Windows platforms (mingw, MSVC) support only a subset of 20POSIX-specified values for the @env{TZ} environment variable, 21consisting of a time zone abbreviation containing exactly three ASCII 22letters with no daylight saving time or angle brackets, and with no 23support for @code{tz} database settings like 24@code{TZ='America/New_York'}. Even this subset does not work on 25applications built via the Universal Windows Platform, as it does not 26make environment variables like @env{TZ} available to applications. 27@item 28Older POSIX platforms do not support angle brackets in @env{TZ} values, 29as this feature was added in IEEE Std 1003.1-2001. 30@end itemize 31