[tz] Epic fail for DST fallback in hospital health records

Paul Eggert eggert at cs.ucla.edu
Mon Nov 5 05:08:21 UTC 2018


Guy Harris wrote:
> the Windows API offers GetSystemTimeAsFileTime(), which supplies tenths-of-microseconds-since-the-FILETIME-epoch ("January 1, 1601 (UTC)"

As I understand it, it is not so much the API as the operating procedure 
underneath. One problem is that when an MS-Windows machine is powered off during 
a DST transition, it does not update the time properly when it is powered back 
on. In a How-To Geek article published earlier today, Chris Hoffman says the 
problem occurred with MS-Windows 10 this weekend, and I recall hearing about 
similar issues years ago. See:

Hoffman C. Some Windows 10 Clocks Didn’t “Fall Back,” Here’s How to Fix It. 
How-To Geek. 2018-11-04 15:23 EDT. 
https://www.howtogeek.com/fyi/some-windows-10-clocks-didn%e2%80%99t-%e2%80%9cfall-back%e2%80%9d-here%e2%80%99s-how-to-fix-it/

Kuhn M. IBM PC Real Time Clock should run in UT. 2016-10-29. 
https://www.cl.cam.ac.uk/~mgk25/mswish/ut-rtc.html

PS. I don't know whether the "EDT" in Hoffman's article's timestamp reflects the 
MS-Windows 10 bug or is a subtle joke; it could be both.


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