Should GetLocalTime () "skip back"?

I know I QueryPerformanceCounter

can return values ​​that are not monotonic / intermittent (i.e. time can appear backwards) due to sampling from unsynchronized clocks distributed across multicore or multiprocessor architectures.

I would have thought I had GetLocalTime()

avoided these problems, although I cannot find anything definite to say about it. When I created this function:

int GetTimeAsMillisecondsSinceMidnight()
    SYSTEMTIME theTime;
    GetLocalTime( &theTime );
    return 3600000*theTime.wHour + 60000*theTime.wMinute
        + 1000*theTime.wSecond + theTime.wMilliseconds;


... I was surprised to create events at 20-30 per second, timestamp using the return value from this function, and find out that sometimes the timestamp "bounced back" by as much as 4 seconds on a reasonably updated 64-bit Windows 8 system running on a Core i7 processor.

What is the likely cause of this "jump back" in time? If GetLocalTime()

is the culprit, are there any alternatives that have similar resolution / precision but avoid the timing gap issues?


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