std::gmtime

 

C++

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Utilities library

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strong_order weak_order partial_order strong_equal weak_equal	strong_ordering weak_ordering partial_ordering strong_equality weak_equality	is_eqis_neqis_ltis_lteqis_gtis_gteq
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Date and time utilities

duration (C++11) time_point (C++11) time_of_day (C++20)	clock_time_conversion (C++20) clock_cast (C++20)
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Calendars
day (C++20) month (C++20) year (C++20) weekday (C++20) operator/ (C++20) year_month_day (C++20) year_month_day_last (C++20) year_month_weekday (C++20) year_month_weekday_last (C++20)	weekday_indexed (C++20) weekday_last (C++20) month_day (C++20) month_day_last (C++20) month_weekday (C++20) month_weekday_last (C++20) year_month (C++20)
Time zones
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C-style date and time

 

C-style date and time utilities

Functions

Time manipulation

difftime

time

clock

timespec_get (C++17)

Format conversions

asctime

ctime

strftime

wcsftime

gmtime

localtime

mktime

Constants

CLOCKS_PER_SEC

Types

tm

time_t

clock_t

timespec (C++17)

 

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

Converts given time since epoch as std::time_t value into calendar time, expressed in Coordinated Universal Time (UTC).

Parameters

time

-

pointer to a 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.

Example

Run this code

#include <iostream>
#include <iomanip>
#include <ctime>
 
int main()
{
    std::time_t t = std::time(nullptr);
    std::cout << "UTC:   " << std::put_time(std::gmtime(&t), "%c %Z") << '\n';
    std::cout << "local: " << std::put_time(std::localtime(&t), "%c %Z") << '\n';
}

Output:

UTC:   Wed Dec 28 11:44:28 2011 GMT
local: Wed Dec 28 06:44:28 2011 EST

See also

localtime

converts time since epoch to calendar time expressed as local time (function)