QueryPerformanceFrequency changes?

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#1659

From: poojo hackma
Date: Wed, 27 Jun 2007 16:28

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Does the QueryPerformanceFrequency value on a system change often?

I am currently editing some code that is about 10 years old, and the first 
few lines of each section in many parts of the code call 
QueryPerformanceFrequency and return if the result is zero.

From what I understand, QueryPerformanceFrequency will return zero only when 
the hardware does not support the high-resolution performance counter.

So, whenever my class initializes, I'd like to call 
QueryPerformanceFrequency and store the value in a class variable so that it 
does not have to be called again and again.

But, is there any reason for a system to return different values at 
different times? I don't understand why the old code calls this API so often 
if it just returns the same LARGE_INTEGER value every time.

Could someone explain? Was this bad coding years ago, or was there a reason?

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Subject: QueryPerformanceFrequency changes?
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