chrono

问题 I am trying to use std::chrono to make a std::string but running into issues. Here is the C(-ish) code I want to mimick: std::uint32_t time_date_stamp = 1484693089; char date[100]; struct tm *t = gmtime(reinterpret_cast<const time_t*>(&time_date_stamp)); strftime(date, sizeof(date), "%Y-%m-%d %I:%M:%S %p", t); My starting point is always this std::uint32_t , it is from a data format I do not control. Sorry I do not have any C++ as a starting point, I do not even know how to make a std::chrono

来源： https://stackoverflow.com/questions/58603446/convert-timestamp-to-the-formatted-date-time-using-c

来源： https://stackoverflow.com/questions/58603446/convert-timestamp-to-the-formatted-date-time-using-c

来源： https://stackoverflow.com/questions/58603446/convert-timestamp-to-the-formatted-date-time-using-c

来源： https://stackoverflow.com/questions/58603446/convert-timestamp-to-the-formatted-date-time-using-c

问题 I get a timestamp from a GPS device in a gps_data struct as a double. I'd like to convert this GPS timestamp to UTC and TAI times, something simple as: void handle_gps_timestamp(double timestamp) { double utc = utc_from_gps(timestamp); double tai = tai_from_gps(timestamp); do_stuff(gps, utc, tai); } Luckily I found Howard Hinnant's date and timezone library (proposed for C++20) that seems to provide this exact functionality. Unfortunately, at least from what I can see, the date/tz/chrono

问题 For a winapi wrapper I want to use chrono for a duration given to the call. The code example: bool setTimer(std::chrono::duration<std::chrono::milliseconds> duration) { unsigned int dwDuration = Do some chrono magic here SetTimer(m_hWnd,1,dwDuration,0); } dwDuration has to be in milliseconds. First question: How do to the magic. Second question: Is the parameter declaration okay? 回答1: The name of the type is std::chrono::milliseconds , and it has a member function count() that returns the

问题 I am trying to get 1 millisecond delay but i am getting 15 times higher.I have also tried with windows Sleep(1) function which was also giving me the same result. why am i not getting exact millisecond delay? Where as it works with 1 second delay. #include <iostream> #include <Windows.h> #include <thread> #include <chrono> void counter1(); auto main() -> int { std::thread p(&counter1); p.join(); return 0; } void counter1() { int nStep = 0; const int STEP = 1000; auto start = std::chrono::high

问题 What is the difference between the C++20 chrono types/values month{7} and months{7} ? Isn't it confusing to have two such similar names? 回答1: Yes, it can be confusing to have both month and months when first encountering this library. However there are consistent naming conventions in this library to help reduce that confusion. And the benefit is having a clear separation of distinct semantics while retaining short intuitive names. months All "predefined" chrono::duration types are plural:

问题 What is the difference between the C++20 chrono types/values month{7} and months{7} ? Isn't it confusing to have two such similar names? 回答1: Yes, it can be confusing to have both month and months when first encountering this library. However there are consistent naming conventions in this library to help reduce that confusion. And the benefit is having a clear separation of distinct semantics while retaining short intuitive names. months All "predefined" chrono::duration types are plural: