std::chrono::operator<< (std::chrono::utc_time)
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|   template <class CharT, class Traits, class Duration> std::basic_ostream<CharT, Traits>&  | 
(since C++20) | |
Outputs tp into the stream os, as if by std::chrono::to_stream(os, fmt, tp), where fmt is a string containing "%F %T" widened to CharT.
Return value
os.
See also
|    outputs a utc_time into a stream according to the provided format   (function template)  |