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

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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)
is_clock (C++20)
utc_clock (C++20)
tai_clock (C++20)
high_resolution_clock (C++11)
gps_clock (C++20)
file_clock (C++20)
local_t (C++20)
Time of day
is_amis_pm (C++20)(C++20)
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)
year_month_day (C++20)
year_month_day_last (C++20)
year_month_weekday (C++20)
year_month_weekday_last (C++20)
weekday_indexed (C++20)
weekday_last (C++20)
month_day (C++20)
month_day_last (C++20)
month_weekday (C++20)
month_weekday_last (C++20)
year_month (C++20)
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::file_clock

Member functions
file_clock::now

file_clock::to_sysfile_clock::from_sys (optional*)

file_clock::to_utcfile_clock::from_utc (optional*)
Time point I/O
operator<<
formatter<std::chrono::file_time>
from_stream

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template<class Duration> staticstd::chrono::sys_time</see below/> to_sys(conststd::chrono::file_time<Duration>& t);	(1)	(since C++20) (optional*)
template<class Duration> staticstd::chrono::file_time</see below/> from_sys(conststd::chrono::sys_time<Duration>& t);	(2)	(since C++20) (optional*)

1) Converts thefile_timet to asys_time representing the same point in time.

2) Converts thesys_timet to afile_time representing the same point in time.

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

These function templates are optional: an implementation may choose to instead provideto_utc() andfrom_utc().

[edit]Return value

1) Asys_time representing the same point in time as the argument.

2) Afile_time representing the same point in time as the argument.

[edit]Notes

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

[edit]Example

This section is incomplete
Reason: no example

[edit]See also

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