std::time_t
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                    |   Defined in header  <ctime>
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|   typedef /* unspecified */ time_t;  | 
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Arithmetic type capable of representing times.
Although not defined, this is almost always an integral value holding the number of seconds (not counting leap seconds) since 00:00, Jan 1 1970 UTC, corresponding to POSIX time.
See also
|    returns the current time of the system as time since epoch  (function)  | |
|    converts time since epoch to calendar time expressed as local time  (function)  | |
|    converts time since epoch to calendar time expressed as Universal Coordinated Time  (function)  |