home | help 
std::time(3)		       C++ Standard Libary		    std::time(3)

NAME
     std::time - std::time

Synopsis
	Defined in header <ctime>
	std::time_t time( std::time_t* arg );

	Returns  the  current calendar time encoded as a std::time_t object, and
     also stores
	it in the object pointed to by arg, unless arg is a null pointer.

Parameters
	arg - pointer to a std::time_t object to  store  the  time,  or  a  null
     pointer

Return value
	Current   calendar  time  encoded  as  std::time_t  object  on	success,
     (std::time_t)(-1) on
	error. If arg is not null, the return value is also stored in the object
     pointed to
	by arg.

Notes
	The encoding of calendar time in std::time_t is  unspecified,  but  most
     systems
	conform  to  the POSIX specification and return a value of integral type
     holding 86400
	times the number of calendar days since the Epoch  plus  the  number  of
     seconds that
	have  passed  since the last midnight UTC. Most notably, POSIX time does
     not (and can
	not) take leap seconds into account, so that this integral value is  not
     equal to the
	number	of  S.I. seconds that have passed since the epoch, but rather is
     reduced with
	the number of leap seconds that have occurred since the epoch. Implemen-
     tations in
	which std::time_t is a 32-bit signed integer (many historical  implemen-
     tations) fail
	in the year 2038.

Example
     // Run this code

      #include <ctime>
      #include <iostream>

      int main()
      {
	  std::time_t result = std::time(nullptr);
	  std::cout << std::asctime(std::localtime(&result))
		    << result << " seconds since the Epoch\n";
      }

Possible output:
      Wed Sep 21 10:27:52 2011
      1316615272 seconds since the Epoch

See also
	timespec_get  returns the calendar time in seconds and nanoseconds based
     on a given
	(C++17)      time base
		     (function)
	localtime    converts time since epoch to calendar time expressed as lo-
     cal time
		     (function)
		     converts time since epoch to  calendar  time  expressed  as
     Universal
	gmtime	     Coordinated Time
		     (function)
	system_clock wall clock time from the system-wide realtime clock
	(C++11)      (class)
	C documentation for
	time

http://cppreference.com 	   2024.06.10			    std::time(3)
home | help