std::chrono:: get_tzdb_list, std::chrono:: get_tzdb, std::chrono:: remote_version, std::chrono:: reload_tzdb

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C++
Utilities library
General utilities
Relational operators (deprecated in C++20)
Date and time utilities
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Time of day
(C++20) (C++20)
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Calendar
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Time zone
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get_tzdb get_tzdb_list reload_tzdb remote_version
(C++20) (C++20) (C++20) (C++20)
(C++20)
chrono I/O
(C++20)
C-style date and time
std:: chrono :: tzdb_list & get_tzdb_list ( ) ;
(1) (since C++20)
const std:: chrono :: tzdb & get_tzdb ( ) ;
(2) (since C++20)
std:: string remote_version ( ) ;
(3) (since C++20)
const std:: chrono :: tzdb & reload_tzdb ( ) ;
(4) (since C++20)

These functions provide access to the program-wide time zone database.

1) Returns a reference to the global std::chrono::tzdb_list singleton. If this is the first access to the database, initialize the database. After the initialization, the database will hold a single initialized std::chrono::tzdb object. This function is thread-safe: concurrent calls to this function from multiple threads do not introduce a data race.
2) Returns a reference to the first std::chrono::tzdb object held by the tzdb_list singleton. Equivalent to std :: chrono :: get_tzdb_list ( ) . front ( ) .
3) Returns a string containing the latest remote database version.
4) If remote_version ( ) ! = get_tzdb ( ) . version , pushes a new tzdb object representing the remote database to the front of the tzdb_list singleton referenced by get_tzdb_list() . Otherwise there are no effects. No references, pointers or iterators are invalidated. Calling this function concurrently with get_tzdb_list ( ) . front ( ) or get_tzdb_list ( ) . erase_after ( ) does not introduce a data race.

Exceptions

1) std::runtime_error if for any reason a reference to a tzdb_list containing one or more valid tzdb cannot be returned.

Return value

1) A reference to the global std::chrono::tzdb_list singleton.
2) std :: chrono :: get_tzdb_list ( ) . front ( ) .
3) A string containing the latest remote database version.
4) std :: chrono :: get_tzdb_list ( ) . front ( ) (after any update made by this function).
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