29 Time library [time]

29.11 Time zones [time.zone]

29.11.2 Time zone database [time.zone.db] Class tzdb [time.zone.db.tzdb]

namespace std::chrono { struct tzdb { string version; vector<time_zone> zones; vector<time_zone_link> links; vector<leap_second> leap_seconds; const time_zone* locate_zone(string_view tz_name) const; const time_zone* current_zone() const; }; }
Each vector in a tzdb object is sorted to enable fast lookup.
const time_zone* locate_zone(string_view tz_name) const;
  • If zones contains an element tz for which tz.name() == tz_name, a pointer to tz;
  • otherwise, if links contains an element tz_l for which tz_l.name() == tz_name, then a pointer to the element tz of zones for which tz.name() == tz_l.target().
[Note 1: 
A time_zone_link specifies an alternative name for a time_zone.
— end note]
Throws: If a const time_zone* cannot be found as described in the Returns: element, throws a runtime_error.
[Note 2: 
On non-exceptional return, the return value is always a pointer to a valid time_zone.
— end note]
const time_zone* current_zone() const;
Returns: A pointer to the time zone which the computer has set as its local time zone.