C Date and time utilities
From cppreference.com
                    
                                        
                    
                    
                                                            
                    Functions
|   Defined in header  
<ctime>  | |
 Time manipulation | |
|   computes the difference between times  (function)  | |
|   returns the current time of the system as time since epoch  (function)  | |
|   returns raw processor clock time since the program is started  (function)  | |
|    (C++17)  | 
  returns the calendar time in seconds and nanoseconds based on a given time base  (function)  | 
 Format conversions | |
|   converts a std::tm object to a textual representation  (function)  | |
|   converts a std::time_t object to a textual representation  (function)  | |
|   converts a std::tm object to custom textual representation  (function)  | |
|   converts a std::tm object to custom wide string textual representation  (function)  | |
|   converts time since epoch to calendar time expressed as Universal Coordinated Time  (function)  | |
|   converts time since epoch to calendar time expressed as local time  (function)  | |
|   converts calendar time to time since epoch  (function)  | |
Constants
|   number of processor clock ticks per second  (macro constant)  | 
Types
|   calendar time type  (class)  | |
|   time since epoch type  (typedef)  | |
|   process running time  (typedef)  | |
|   (C++17)  | 
 time in seconds and nanoseconds (struct)  | 
See also
|   C documentation for Date and time utilities 
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