std::chrono::system_clock::to_time_t
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                    < cpp | chrono | system clock
                    
                                                            
                    |   static std::time_t to_time_t( const time_point& t ) noexcept;  | 
(since C++11) | |
Converts t to a std::time_t type. 
If std::time_t has lower precision, it is implementation-defined whether the value is rounded or truncated.
Parameters
| t | - | system clock time point to convert | 
Return value
A std::time_t value representing t.
See also
|    [static]  | 
   converts std::time_t to a system clock time point  (public static member function)  |