std::chrono::file_clock::to_utc, std::chrono::file_clock::from_utc

 

C++

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Technical Specifications

 

Utilities library

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Date and time utilities

duration (C++11) time_point (C++11) time_of_day (C++20)	clock_time_conversion (C++20) clock_cast (C++20)
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Time zones
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C-style date and time

 

std::chrono::file_clock

Member functions

file_clock::now

file_clock::to_sysfile_clock::from_sys (provided only if to_utc and from_utc are not provided)

file_clock::to_utcfile_clock::from_utc (provided only if to_sys and from_sys are not provided)

Time point I/O

operator<<

to_stream

from_stream

 

template <class Duration> static std::chrono::utc_time</*see below*/>     to_utc(const std::chrono::file_time<Duration>& t);	(1)	(since C++20) (optional)
template <class Duration> static std::chrono::file_time</*see below*/>     from_utc(const std::chrono::utc_time<Duration>& t);	(2)	(since C++20) (optional)

1) Converts the file_time t to a utc_time representing the same point in time.

2) Converts the utc_time t to a file_time representing the same point in time.

The duration of the return type is computed from Duration in an unspecified manner.

These function templates are optional: an implementation may choose to instead provide to_sys and from_sys.

Return value

1) A utc_time representing the same point in time as the argument.

2) A file_time representing the same point in time as the argument.

Notes

User code should usually use std::chrono::clock_cast, which provides a generic interface to convert time points between clocks, rather than call these functions directly.

See also

to_sysfrom_sys [static] (optional)	converts between file_time and sys_time (public static member function)
clock_cast (C++20)	convert time points of one clock to another (function template)