QueryPerformanceCounter

BOOL QueryPerformanceCounter(
LARGE_INTEGER *lpPerformanceCount
);

Description

Retrieves the current value of the high-resolution performance counter.

The performance counter is a time-of-day counter. The current value of the counter is retrieved in the lpPerformanceCount parameter.

To convert the counter value to a meaningful unit of time, you need to use the QueryPerformanceFrequency function to get the frequency of the counter. The frequency is the number of ticks per second. Divide the counter value by the frequency to obtain the duration in seconds.

Parameters

Name	Type	Description
`lpPerformanceCount`	`PLARGE_INTEGER` (`LARGE_INTEGER*`)	A pointer to a `LARGE_INTEGER` that receives the current performance-counter value.

Return Value

Type	Description
`BOOL`	If the function succeeds, the return value is nonzero. If the function fails, the return value is zero. To get extended error information, call `GetLastError`.

Remarks

Requirement	Description
Minimum supported client	Windows Vista [desktop apps only]
Minimum supported server	Windows Server 2008 [desktop apps only]
Target Platform	Windows
Header	`Windows.h`
Library	`Corelt.lib`
DLL	`Corelt.dll`

Example


#include <windows.h>
#include <iostream>

int main() {
    LARGE_INTEGER frequency;
    LARGE_INTEGER startCount;
    LARGE_INTEGER endCount;
    double elapsedTime = 0.0;

    // Get the performance counter frequency
    if (QueryPerformanceFrequency(&frequency)) {
        // Get the starting performance counter value
        if (QueryPerformanceCounter(&startCount)) {
            // Simulate some work
            Sleep(100); // Sleep for 100 milliseconds

            // Get the ending performance counter value
            if (QueryPerformanceCounter(&endCount)) {
                // Calculate the elapsed time in seconds
                elapsedTime = static_cast<double>(endCount.QuadPart - startCount.QuadPart) / frequency.QuadPart;
                std::cout << "Elapsed time: " << elapsedTime << " seconds." << std::endl;
            }
        }
    } else {
        std::cerr << "QueryPerformanceFrequency failed. Error: " << GetLastError() << std::endl;
    }

    return 0;
}