SetSystemTimeAdjustmentPrecise 函式 (sysinfoapi.h)

啟用或停用系統當天時鐘的定期時間調整。 啟用時，這類時間調整可用來同步處理一天的時間與一些其他時間來源資訊。

語法

BOOL SetSystemTimeAdjustmentPrecise(
  [in] DWORD64 dwTimeAdjustment,
  [in] BOOL    bTimeAdjustmentDisabled
);

參數

[in] dwTimeAdjustment

提供調整的時鐘更新頻率。

[in] bTimeAdjustmentDisabled

提供旗標，指定系統要使用的時間調整模式。

TRUE值表示系統應該使用自己的內部機制同步處理一天的時間。 在此情況下， 會忽略 dwTimeAdjustment 的值。

FALSE值表示應用程式處於控制狀態，而且在每次時鐘更新中斷時，都會將 dwTimeAdjustment的指定值新增至當日時鐘。

傳回值

如果函式成功，則傳回值為非零。

如果此函式失敗，則傳回值為零。 若要取得擴充的錯誤資訊，請呼叫 GetLastError。 函式失敗的其中一種方式是，如果呼叫端沒有SE_SYSTEMTIME_NAME許可權。

備註

若要使用此函式，呼叫端必須具有系統時間許可權 (SE_SYSTEMTIME_NAME) 。 預設會停用此許可權。 使用 AdjustTokenPrivileges 函式在呼叫此函式之前啟用許可權，然後在函式呼叫之後停用許可權。 如需詳細資訊，請參閱下列程式碼範例。

範例

此範例示範如何啟用系統時間許可權、使用 GetSystemTimeAdjustmentPrecise 和 SetSystemTimeAdjustmentPrecise調整系統時鐘，以及如何整齊列印目前的系統時間調整。

/****************************************************************** 
* 
* ObtainRequiredPrivileges 
* 
* Enables system time adjustment privilege. 
* 
******************************************************************/ 
HRESULT 
ObtainRequiredPrivileges() 
{ 
    HRESULT hr; 
    HANDLE hProcToken = NULL; 
    TOKEN_PRIVILEGES tp = {0}; 
    LUID luid; 

    if (!LookupPrivilegeValue(NULL, SE_SYSTEMTIME_NAME, &luid)) 
    { 
        hr = HRESULT_FROM_WIN32(GetLastError()); 
        printf("Failed to lookup privilege value. hr=0x%08x\n", hr); 
        return hr; 
    } 

    // get the token for our process 
    if (!OpenProcessToken(GetCurrentProcess(), 
    TOKEN_ADJUST_PRIVILEGES | TOKEN_QUERY, 
    &hProcToken)) 
    { 
        hr = HRESULT_FROM_WIN32(GetLastError()); 
        printf("Failed to open process token. hr=0x%08x\n", hr); 
        return hr; 
    } 

    // Enable just the SYSTEMTIME privilege 
    tp.PrivilegeCount = 1; 
    tp.Privileges[0].Luid = luid; 
    tp.Privileges[0].Attributes = SE_PRIVILEGE_ENABLED; 

    if (!AdjustTokenPrivileges(hProcToken, FALSE, &tp, 0, NULL, NULL)) 
    { 
        hr = HRESULT_FROM_WIN32(GetLastError()); 
        printf("Failed to adjust process token privileges. hr=0x%08x\n", hr); 
    } 
    else 
    { 
        hr = S_OK; 
        printf("Added SYSTEMTIME privilege to the process token\n"); 
    } 
    
    if (NULL != hProcToken) 
    { 
        CloseHandle(hProcToken); 
    } 
    return hr; 
} 

/****************************************************************** 
* 
* PrintCurrentClockAdjustments 
* 
* Prints current values of the system time adjustments. 
* 
******************************************************************/ 
void 
PrintCurrentClockAdjustments() 
{ 
    // More granular clock adjustments 
    DWORD64 ullCurrentAdjustment = 0; 
    DWORD64 ullTimeIncrement = 0; 
    BOOL bEnabledPrecise = 0; 
    HRESULT hrPrecise = S_OK; 

    // Legacy clock adjustments 
    DWORD dwCurrentAdjustment = 0; 
    DWORD dwTimeIncrement = 0; 
    BOOL bEnabled = 0; 
    HRESULT hr = S_OK; 

    if (!GetSystemTimeAdjustmentPrecise(&ullCurrentAdjustment, &ullTimeIncrement, &bEnabledPrecise)) 
    { 
        hrPrecise = HRESULT_FROM_WIN32(GetLastError()); 
    } 

    if (!GetSystemTimeAdjustment(&dwCurrentAdjustment, &dwTimeIncrement, &bEnabled)) 
    { 
        hr = HRESULT_FROM_WIN32(GetLastError()); 
    } 

    printf("Precise_ADJ:%I64u Precise_INCR:%I64u Precise_EN:%d Precise_hr:0x%08x ADJ:%u INCR:%u EN:%d hr:0x%08x\n", 
            ullCurrentAdjustment, ullTimeIncrement, bEnabledPrecise, hrPrecise, 
            dwCurrentAdjustment, dwTimeIncrement, bEnabled, hr); 
} 

/****************************************************************** 
* 
* RunNewAdjustmentSequence 
* 
* Adjust the system time using high-resolution 
* GetSystemTimeAdjustmentPrecise() and SetSystemTimeAdjustmentPrecise() API. 
* 
******************************************************************/ 
void 
RunNewAdjustmentSequence(DWORD dwPPMAdjustment) 
{ 
    DWORD64 ullCurrentAdjustment = 0; 
    DWORD64 ullTimeIncrement = 0; 
    BOOL bEnabledPrecise = 0; 
    LARGE_INTEGER liPerfCounterFrequency = {0}; 
    DWORD dwNewAdjustmentUnits; 
    const DWORD cMicroSecondsPerSecond = 1000000; 

    if (dwPPMAdjustment > 1000) 
    { 
        printf("Adjustment too large. Skipping new adjustment sequence.\n"); 
        return; 
    } 

    printf("Starting adjustment sequence using new API...\n"); 

    if (!GetSystemTimeAdjustmentPrecise(&ullCurrentAdjustment, &ullTimeIncrement, &bEnabledPrecise)) 
    { 
        printf("Failed to read the system time adjustment. Adjustment sequence aborted. hr:0x%08x\n", 
        HRESULT_FROM_WIN32(GetLastError())); 
        return; 
    } 

    (void)QueryPerformanceFrequency(&liPerfCounterFrequency); 
    printf("System Performance Counter Frequency: %I64u\n", 
    liPerfCounterFrequency.QuadPart); 


    dwNewAdjustmentUnits = (DWORD)(((float) dwPPMAdjustment * liPerfCounterFrequency.QuadPart/ cMicroSecondsPerSecond)); 

    printf("Adjusting the system clock by +%d PPM (+%d new units)\n", 
    dwPPMAdjustment, dwNewAdjustmentUnits); 

    if (!SetSystemTimeAdjustmentPrecise(ullCurrentAdjustment + dwNewAdjustmentUnits, FALSE)) 
    { 
        printf("Failed to set the system time adjustment. hr:0x%08x\n", 
        HRESULT_FROM_WIN32(GetLastError())); 
    } 

    PrintCurrentClockAdjustments(); 

    printf("Restoring system clock adjustment settings\n"); 

    if (!SetSystemTimeAdjustmentPrecise(ullCurrentAdjustment, FALSE)) 
    { 
        printf("Failed to set the system time adjustment. hr:0x%08x\n", 
        HRESULT_FROM_WIN32(GetLastError())); 
    } 

    PrintCurrentClockAdjustments(); 

    printf("Adjusting the system clock by -%d PPM (-%d new units)\n", 
    dwPPMAdjustment, dwNewAdjustmentUnits); 

    if (!SetSystemTimeAdjustmentPrecise(ullCurrentAdjustment - dwNewAdjustmentUnits, FALSE)) 
    { 
        printf("Failed to set the system time adjustment. hr:0x%08x\n", 
        HRESULT_FROM_WIN32(GetLastError())); 
    } 

    PrintCurrentClockAdjustments(); 

    printf("Restoring system clock adjustment settings\n"); 

    if (!SetSystemTimeAdjustmentPrecise(ullCurrentAdjustment, FALSE)) 
    { 
        printf("Failed to set the system time adjustment. hr:0x%08x\n", 
        HRESULT_FROM_WIN32(GetLastError())); 
    } 

    PrintCurrentClockAdjustments(); 

    printf("Adjustment sequence complete\n\n"); 
}

需求

另請參閱

GetSystemTimeAdjustmentPrecise