QueryPerformanceFrequency.md

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Function name : QueryPerformanceFrequency

Group: Time - Library: kernel32

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The QueryPerformanceFrequency function retrieves the frequency of the high-resolution performance counter, if one exists. The frequency cannot change while the system is running.

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Code examples:

Using the high-resolution performance counter

Declaration:

BOOL QueryPerformanceFrequency(
  LARGE_INTEGER *lpFrequency   // current frequency
);  

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FoxPro declaration:

DECLARE INTEGER QueryPerformanceFrequency IN kernel32;
	STRING @lpFrequency  

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Parameters:

lpFrequency [out] Pointer to a variable that receives the current performance-counter frequency, in counts per second.

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Return value:

If the installed hardware supports a high-resolution performance counter, the return value is nonzero.

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Comments:

Note that the frequency of the high-resolution performance counter is not the processor speed.
See GetTickCount function.

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