std::chrono::file_clock::to_sys, std::chrono::file_clock::from_sys

From cppreference.com
< cpplrm; | chronolrm; | file clock
Date and time utilities
(C++11)
(C++11)
Clocks
(C++20)
(C++20)
(C++20)
(C++20)
(C++20)
Calendars
(C++20)
(C++20)
(C++20)
(C++20)
(C++20)
Time zones
(C++20)
(C++20)
(C++20)
(C++20)
(C++20)
(C++20)
C-style date and time
std::chrono::file_clock
Member functions

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

(provided only if to_sys and from_sys are not provided)
Time point I/O
template <class Duration>

static std::chrono::sys_time</*see below*/>

to_sys(const std::chrono::file_time<Duration>& t);
(1) (since C++20)
(optional)
template <class Duration>

static std::chrono::file_time</*see below*/>

from_sys(const std::chrono::sys_time<Duration>& t);
(2) (since C++20)
(optional)
1) Converts the file_time t to a sys_time representing the same point in time.
2) Converts the sys_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_utc and from_utc.

Return value

1) A sys_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

[static] (optional)
converts between file_time and utc_time
(public static member function)
convert time points of one clock to another
(function template)