I’m trying to write a time string with a millisecond precision in MSVC 19.11 with /stc:c++latest.
With this i get 7 digits accuracy, what i don’t want.
auto now = std::chrono::system_clock::now();
std::cout << std::format("{0:%d.%m.%Y %H:%M:%S}", now);
I tried std::cout << std::format("{0:%d.%m.%Y %H:%M:%S.3}", now); and some possibilities of std::setprecision(3) in vain.
Is there a solution to format it there or do i need to change "now"?
>Solution :
auto now = std::chrono::floor<std::chrono::milliseconds>(std::chrono::system_clock::now());
std::cout << std::format("{0:%d.%m.%Y %H:%M:%S}", now);
or:
auto now = std::chrono::system_clock::now();
std::cout << std::format("{0:%d.%m.%Y %H:%M:%S}", std::chrono::floor<std::chrono::milliseconds>(now));
I.e. the precision of the output is controlled by the precision of the input.
Aside: You can also use %T in place of %H:%M:%S if desired.