Std::gmtime (3) Linux Manual Page

std::gmtime – std::gmtime

Synopsis

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

std::gmtime (3) Linux Manual Page