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

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Date and time library

Time point
time_point (C++11)
clock_time_conversion (C++20)
clock_cast (C++20)
Duration
duration (C++11)
Clocks
system_clock (C++11)
steady_clock (C++11)
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Time of day
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make12make24 (C++20)(C++20)
hh_mm_ss (C++20)

Calendar
day (C++20)
month (C++20)
year (C++20)
weekday (C++20)
operator/ (C++20)
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year_month_weekday (C++20)
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weekday_indexed (C++20)
weekday_last (C++20)
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last_speclast (C++20)(C++20)
`chrono` I/O
parse (C++20)

Time zone
tzdb (C++20)
tzdb_list (C++20)
get_tzdbget_tzdb_listreload_tzdbremote_version (C++20)(C++20)(C++20)(C++20)
sys_info (C++20)
local_info (C++20)
nonexistent_local_time (C++20)
ambiguous_local_time (C++20)
locate_zone (C++20)
current_zone (C++20)
time_zone (C++20)
choose (C++20)
zoned_traits (C++20)
zoned_time (C++20)
time_zone_link (C++20)
leap_second (C++20)
leap_second_info (C++20)
get_leap_second_info (C++20)
C-style date and time

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std::chrono::tzdb_list& get_tzdb_list();	(1)	(since C++20)
conststd::chrono::tzdb& get_tzdb();	(2)	(since C++20)
std::string remote_version();	(3)	(since C++20)
conststd::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 globalstd::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 initializedstd::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 firststd::chrono::tzdb object held by thetzdb_list singleton. Equivalent tostd::chrono::get_tzdb_list().front().

3) Returns a string containing the latest remote database version.

4) Ifremote_version()!= get_tzdb().version, pushes a newtzdb object representing the remote database to the front of thetzdb_list singleton referenced byget_tzdb_list(). Otherwise there are no effects. No references, pointers or iterators are invalidated. Calling this function concurrently withget_tzdb_list().front() orget_tzdb_list().erase_after() does not introduce a data race.