NAME¶

std::chrono::system_clock::to_time_t - std::chrono::system_clock::to_time_t

Synopsis¶

static std::time_t to_time_t( const time_point& t ) noexcept; (since C++11)

Converts t to a std::time_t type.

If std::time_t has lower precision, it is implementation-defined whether the value
is rounded or truncated.

Parameters¶

t - system clock time point to convert

Return value¶

A std::time_t value representing t.

Example¶

Get the current time as a std::time_t two ways.

// Run this code

#include <chrono>
#include <ctime>
#include <iostream>
#include <thread>
using namespace std::chrono_literals;

int main()
{
// The old way
std::time_t oldt = std::time({});

std::this_thread::sleep_for(2700ms);

// The new way
auto const now = std::chrono::system_clock::now();
std::time_t newt = std::chrono::system_clock::to_time_t(now);

std::cout << "newt - oldt == " << newt - oldt << " s\n";
}

Possible output:¶

newt - oldt == 3 s

See also¶

from_time_t converts std::time_t to a system clock time point
[static] (public static member function)