闰秒是否存储在Mac OS X上的任何地方？

问题描述：

我在我的系统上运行了find /usr/share/zoneinfo/ -type f -exec file {} \; |grep -v 'no leap'，每个时区文件都表示它没有闰秒。 Mac OS X上的任何地方都可以存储闰秒，我可以通过强大的方式获取？我正在编写一个需要闰秒的库，所以我宁愿不通过网络连接，尽管可以接受某种系统调用。闰秒是否存储在Mac OS X上的任何地方？

至于我知道，macOS不会闰秒 - 相反，他们宁愿接受非常古老的时代将会持续十几秒钟，当您的机器跳跃闰秒时，它就会像其他任何时间一样，发生系统内部时钟错误由网络时间服务器纠正。基本上，苹果公司的感觉是，由于计算机时钟不是非常准确，所以使用闰秒会浪费CPU周期。 –

答

有存储在数据库IANA在MacOS没有闰秒信息：在/ usr/share/zoneinfo中

如果你愿意使用第三方C++ 11库，Howard Hinnant's time zone library让你在处理完整的功能闰秒。这确实需要下载IANA数据库。但是你可以配置这个库自动下载它，或者你可以手动下载它，并且库可以访问它。

文档具有这个例子：

#include "tz.h" 
#include <iostream> 

int 
main() 
{ 
    using namespace date; 
    using namespace std::chrono_literals; 
    auto start = to_utc_time(sys_days{2015_y/jul/1} - 500ms); 
    auto end = start + 2s; 
    for (auto utc = start; utc < end; utc += 100ms) 
    { 
     auto sys = to_sys_time(utc); 
     auto tai = to_tai_time(utc); 
     auto gps = to_gps_time(utc); 
     std::cout << format("%F %T SYS == ", sys) 
        << format("%F %T %Z == ", utc) 
        << format("%F %T %Z == ", tai) 
        << format("%F %T %Z\n", gps); 
    } 
}

此示例迭代时间的2015年6月闰秒的附近，比较系统时间，UTC，TAI和GPS时钟标准：

2015-06-30 23:59:59.500 SYS == 2015-06-30 23:59:59.500 UTC == 2015-07-01 00:00:34.500 TAI == 2015-07-01 00:00:15.500 GPS 
2015-06-30 23:59:59.600 SYS == 2015-06-30 23:59:59.600 UTC == 2015-07-01 00:00:34.600 TAI == 2015-07-01 00:00:15.600 GPS 
2015-06-30 23:59:59.700 SYS == 2015-06-30 23:59:59.700 UTC == 2015-07-01 00:00:34.700 TAI == 2015-07-01 00:00:15.700 GPS 
2015-06-30 23:59:59.800 SYS == 2015-06-30 23:59:59.800 UTC == 2015-07-01 00:00:34.800 TAI == 2015-07-01 00:00:15.800 GPS 
2015-06-30 23:59:59.900 SYS == 2015-06-30 23:59:59.900 UTC == 2015-07-01 00:00:34.900 TAI == 2015-07-01 00:00:15.900 GPS 
2015-06-30 23:59:59.999 SYS == 2015-06-30 23:59:60.000 UTC == 2015-07-01 00:00:35.000 TAI == 2015-07-01 00:00:16.000 GPS 
2015-06-30 23:59:59.999 SYS == 2015-06-30 23:59:60.100 UTC == 2015-07-01 00:00:35.100 TAI == 2015-07-01 00:00:16.100 GPS 
2015-06-30 23:59:59.999 SYS == 2015-06-30 23:59:60.200 UTC == 2015-07-01 00:00:35.200 TAI == 2015-07-01 00:00:16.200 GPS 
2015-06-30 23:59:59.999 SYS == 2015-06-30 23:59:60.300 UTC == 2015-07-01 00:00:35.300 TAI == 2015-07-01 00:00:16.300 GPS 
2015-06-30 23:59:59.999 SYS == 2015-06-30 23:59:60.400 UTC == 2015-07-01 00:00:35.400 TAI == 2015-07-01 00:00:16.400 GPS 
2015-06-30 23:59:59.999 SYS == 2015-06-30 23:59:60.500 UTC == 2015-07-01 00:00:35.500 TAI == 2015-07-01 00:00:16.500 GPS 
2015-06-30 23:59:59.999 SYS == 2015-06-30 23:59:60.600 UTC == 2015-07-01 00:00:35.600 TAI == 2015-07-01 00:00:16.600 GPS 
2015-06-30 23:59:59.999 SYS == 2015-06-30 23:59:60.700 UTC == 2015-07-01 00:00:35.700 TAI == 2015-07-01 00:00:16.700 GPS 
2015-06-30 23:59:59.999 SYS == 2015-06-30 23:59:60.800 UTC == 2015-07-01 00:00:35.800 TAI == 2015-07-01 00:00:16.800 GPS 
2015-06-30 23:59:59.999 SYS == 2015-06-30 23:59:60.900 UTC == 2015-07-01 00:00:35.900 TAI == 2015-07-01 00:00:16.900 GPS 
2015-07-01 00:00:00.000 SYS == 2015-07-01 00:00:00.000 UTC == 2015-07-01 00:00:36.000 TAI == 2015-07-01 00:00:17.000 GPS 
2015-07-01 00:00:00.100 SYS == 2015-07-01 00:00:00.100 UTC == 2015-07-01 00:00:36.100 TAI == 2015-07-01 00:00:17.100 GPS 
2015-07-01 00:00:00.200 SYS == 2015-07-01 00:00:00.200 UTC == 2015-07-01 00:00:36.200 TAI == 2015-07-01 00:00:17.200 GPS 
2015-07-01 00:00:00.300 SYS == 2015-07-01 00:00:00.300 UTC == 2015-07-01 00:00:36.300 TAI == 2015-07-01 00:00:17.300 GPS 
2015-07-01 00:00:00.400 SYS == 2015-07-01 00:00:00.400 UTC == 2015-07-01 00:00:36.400 TAI == 2015-07-01 00:00:17.400 GPS

闰秒是否存储在Mac OS X上的任何地方？

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