std::chrono::operator<<(std::chrono::sys_time)

 

C++

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Feature test macros(C++20)

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Symbols index

External libraries

 

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

 

std::chrono::system_clock

Member functions

system_clock::now

system_clock::to_time_t

system_clock::from_time_t

Time point I/O

operator<<

formatter<std::chrono::sys_time>

from_stream

 

Defined in header <chrono>
template<class CharT, class Traits, class Duration > std::basic_ostream<CharT, Traits>&     operator<<(std::basic_ostream<CharT, Traits>& os,                 conststd::chrono::sys_time<Duration>& tp );	(1)	(since C++20)
template<class CharT, class Traits, class Duration > std::basic_ostream<CharT, Traits>&     operator<<(std::basic_ostream<CharT, Traits>& os,                 conststd::chrono::sys_days& tp );	(2)	(since C++20)

Outputs tp into the stream os.

1) Equivalent to:

return os <<std::format(os.getloc(), STATICALLY-WIDEN<CharT>("{:L%F %T}"), tp);

where STATICALLY_WIDEN<CharT>("{:L%F %T}") is "{:L%F %T}" if CharT is char, and L"{:L%F %T}" if CharT is wchar_t.

This overload participates in overload resolution only if std::chrono::treat_as_floating_point_v<typename Duration::rep> is false and Duration(1)<std::chrono::days(1).

2) Equivalent to os <<std::chrono::year_month_day(tp);.

Return value

os

Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

DR	Applied to	Behavior as published	Correct behavior
P2372R3	C++20	the given locale was used by default	L is needed to use the given locale

See also

std::formatter<std::chrono::sys_time> (C++20)	formatting support for sys_time (class template specialization)
format (C++20)	stores formatted representation of the arguments in a new string (function template)
operator<< (C++20)	outputs a year_month_day into a stream (function template)