namespace chr = std::chrono;
using days_duration = chr::duration<int, std::ratio<86400>>;
tm creationTime{0};
if (strptime(__DATE__, "%b %d %Y", &creationTime)) {
auto cTimePoint = chr::system_clock::from_time_t( mktime(&creationTime) );
std::cout << chr::duration_cast<days_duration>(chr::system_clock::now() - cTimePoint).count() << '\n';
}
Wyświetla różnicę w dniach.