RtlQueryPerformanceFrequency - NtDoc

#ifndef _NTRTL_H
#if (PHNT_VERSION >= PHNT_WINDOWS_7)

// rev
/**
 * Retrieves the frequency of the performance counter. The frequency of the performance counter is fixed at system boot and is consistent across all processors.
 * Therefore, the frequency need only be queried upon application initialization, and the result can be cached.
 *
 * @param PerformanceFrequency A pointer to a variable that receives the current performance-counter frequency, in counts per second. 
 * @return Returns TRUE if the function succeeds, otherwise FALSE. On systems that run Windows XP or later, the function will always succeed and will thus never return zero.
 * @sa https://learn.microsoft.com/en-us/windows/win32/api/profileapi/nf-profileapi-queryperformancefrequency
 */
NTSYSAPI
LOGICAL
NTAPI
RtlQueryPerformanceFrequency(
    _Out_ PLARGE_INTEGER PerformanceFrequency
    );

#endif
#endif
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