std::chrono::time_zone:: to_sys

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std::chrono::time_zone
template < class Duration >

auto to_sys ( const std:: chrono :: local_time < Duration > & tp ) const

- > std:: chrono :: sys_time < std:: common_type_t < Duration, std:: chrono :: seconds >> ;
(1) (since C++20)
template < class Duration >

auto to_sys ( const std:: chrono :: local_time < Duration > & tp, std:: chrono :: choose z ) const

- > std:: chrono :: sys_time < std:: common_type_t < Duration, std:: chrono :: seconds >> ;
(2) (since C++20)

Converts the local_time tp in this time zone to the corresponding sys_time .

1) Throws an exception if the conversion is ambiguous or if tp represents a nonexistent time.
2) Resolves ambiguity according to the value of z :
  • If z == std :: chrono :: choose :: earliest , returns the earlier sys_time .
  • If z == std :: chrono :: choose :: latest , returns the later sys_time .
If tp represents a nonexistent time between two UTC time_point s, those two time_point s will be the same, and that time_point will be returned.

Return value

The UTC equivalent of tp according to the rules of this time zone.

Exceptions

1) Throws:

Notes

The precision of the result is at least std::chrono::seconds , and will be finer if the argument has finer precision.

Ambiguous and nonexistent local times can occur as a result of time zone transitions (such as daylight saving time). For example, "2016-03-13 02:30:00" does not exist in the "America/New_York" time zone, while "2016-11-06 01:30:00" in that time zone can correspond to two UTC time points: 2016 - 11 - 06 05 : 30 : 00 UTC and 2016 - 11 - 06 06 : 30 : 00 UTC .

Example

This section is incomplete
Reason: no example
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