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

 

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duration (C++11)
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chrono I/O
parse (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,             const std::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,             const std::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)