NAME¶

std::chrono::system_clock::from_time_t - std::chrono::system_clock::from_time_t

Synopsis¶

static std::chrono::system_clock::time_point from_time_t( std::time_t (since C++11)
t ) noexcept;

Converts t to a time point type, using the coarser precision of the two types.

If time_point has lower precision, it is implementation defined whether the value is
rounded or truncated.

Parameters¶

t - std::time_t value to convert

Return value¶

A value of type std::chrono::system_clock::time_point representing t.

Example¶

// Run this code

#include <iostream>
#include <ctime>
#include <chrono>
#include <thread>

int main()
{
using namespace std::chrono_literals;

const std::time_t t = std::time(nullptr); // usually has "1 second" precision

const auto from = std::chrono::system_clock::from_time_t(t);

std::this_thread::sleep_for(500ms);

const auto diff = std::chrono::system_clock::now() - from;

std::cout << diff << " ("
<< std::chrono::round<std::chrono::milliseconds>(diff)
<< ")\n";
}

Possible output:¶

987654321ns (987ms)

See also¶

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