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std::localtime(3)	       C++ Standard Libary	       std::localtime(3)

NAME
     std::localtime - std::localtime

Synopsis
	Defined in header <ctime>
	std::tm* localtime( const std::time_t* time );

	Converts given time since epoch as std::time_t value into calendar time,
     expressed
	in local time.

Parameters
	time - pointer to a std::time_t object to convert

Return value
	Pointer  to a static internal std::tm object on success, or null pointer
     otherwise.
	The structure may be shared  between  std::gmtime,  std::localtime,  and
     std::ctime, and
	may be overwritten on each invocation.

Notes
	This function may not be thread-safe.

	POSIX  requires  that  this function sets errno to EOVERFLOW if it fails
     because the
	argument is too large.

	POSIX specifies that the timezone  information	is  determined	by  this
     function as if
	by calling tzset, which reads the environment variable TZ.

Example
     // Run this code

      #include <ctime>
      #include <iomanip>
      #include <iostream>
      #include <sstream>

      int main()
      {
	  setenv("TZ",	"/usr/share/zoneinfo/America/Los_Angeles", 1); // POSIX-
     specific

	  std::tm tm{}; // Zero initialise
	  tm.tm_year = 2020 - 1900; // 2020
	  tm.tm_mon = 2 - 1; // February
	  tm.tm_mday = 15; // 15th
	  tm.tm_hour = 10;
	  tm.tm_min = 15;
	  tm.tm_isdst = 0; // Not daylight saving
	  std::time_t t = std::mktime(&tm);

	  std::cout << "UTC:   " << std::put_time(std::gmtime(&t), "%c	%Z")  <<
     '\n';
	  std::cout  <<  "local: " << std::put_time(std::localtime(&t), "%c %Z")
     << '\n';
      }

Possible output:
      UTC:   Sat Feb 15 18:15:00 2020 GMT
      local: Sat Feb 15 10:15:00 2020 PST

See also
		    converts time since epoch to calendar time expressed as Uni-
     versal
	gmtime	    Coordinated Time
		    (function)
	localtime
	localtime_r converts time since epoch to calendar time expressed as  lo-
     cal time
	localtime_s (function)
	(C23)
	(C11)
	C documentation for
	localtime

http://cppreference.com 	   2024.06.10		       std::localtime(3)
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