SYSTEM_POWER_POLICY structure (winnt.h)
Contains information about the current system power policy.
Syntax
typedef struct _SYSTEM_POWER_POLICY {
DWORD Revision;
POWER_ACTION_POLICY PowerButton;
POWER_ACTION_POLICY SleepButton;
POWER_ACTION_POLICY LidClose;
SYSTEM_POWER_STATE LidOpenWake;
DWORD Reserved;
POWER_ACTION_POLICY Idle;
DWORD IdleTimeout;
BYTE IdleSensitivity;
BYTE DynamicThrottle;
BYTE Spare2[2];
SYSTEM_POWER_STATE MinSleep;
SYSTEM_POWER_STATE MaxSleep;
SYSTEM_POWER_STATE ReducedLatencySleep;
DWORD WinLogonFlags;
DWORD Spare3;
DWORD DozeS4Timeout;
DWORD BroadcastCapacityResolution;
SYSTEM_POWER_LEVEL DischargePolicy[NUM_DISCHARGE_POLICIES];
DWORD VideoTimeout;
BOOLEAN VideoDimDisplay;
DWORD VideoReserved[3];
DWORD SpindownTimeout;
BOOLEAN OptimizeForPower;
BYTE FanThrottleTolerance;
BYTE ForcedThrottle;
BYTE MinThrottle;
POWER_ACTION_POLICY OverThrottled;
} SYSTEM_POWER_POLICY, *PSYSTEM_POWER_POLICY;
Members
Revision
The current structure revision.
PowerButton
A POWER_ACTION_POLICY structure that defines the system power action to initiate when the system power button is pressed.
SleepButton
A POWER_ACTION_POLICY structure that defines the system power action to initiate when the system sleep button is pressed.
LidClose
A POWER_ACTION_POLICY structure that defines the system power action to initiate when the system lid switch is closed.
LidOpenWake
The maximum power state (highest Sx value) from which a lid-open event should wake the system. This member must be one of the SYSTEM_POWER_STATE enumeration type values.
Reserved
Reserved.
Idle
A POWER_ACTION_POLICY structure that defines the system power action to initiate when the system idle timer expires.
IdleTimeout
The time that the level of system activity must remain below the idle detection threshold before the system idle timer expires, in seconds.
IdleSensitivity
The level of system activity that defines the threshold for idle detection, expressed as a percentage.
DynamicThrottle
The current system processor dynamic throttling policy. This member must be one of the values described in Processor Performance Control Policy Constants.
Spare2[2]
Reserved.
MinSleep
The minimum system sleep state (lowest Sx value) currently supported. This member must be one of the SYSTEM_POWER_STATE enumeration type values.
MaxSleep
The maximum system sleep state (highest Sx value) currently supported. This member must be one of the SYSTEM_POWER_STATE enumeration type values.
ReducedLatencySleep
The system power state (Sx value) to enter on a system sleep action when there are outstanding latency requirements. This member must be one of the SYSTEM_POWER_STATE enumeration type values. If an application calls RequestWakeupLatency with LT_LOWEST_LATENCY, ReducedLatencySleep will be used in place of MaxSleep.
WinLogonFlags
This member can be zero or WINLOGON_LOCK_ON_SLEEP (0x00000001).
Spare3
Reserved.
DozeS4Timeout
The time to wait between entering the suspend state and entering the hibernate sleeping state, in seconds. A value of zero indicates never hibernate.
BroadcastCapacityResolution
The resolution of change in current battery capacity that should cause the system to be notified of a system power state changed event.
DischargePolicy[NUM_DISCHARGE_POLICIES]
An array of SYSTEM_POWER_LEVEL structures that defines the actions to take at system battery discharge events.
VideoTimeout
The time before the display is turned off, in seconds.
VideoDimDisplay
If this member is TRUE, the system includes support for display dimming.
VideoReserved[3]
Reserved.
SpindownTimeout
The time before power to fixed disk drives is turned off, in seconds.
OptimizeForPower
If this member is TRUE, the system will turn on cooling fans and run the processor at full speed when passive cooling is specified. This causes the operating system to be biased toward using the fan and running the processor at full speed.
FanThrottleTolerance
The lower limit that the processor may be throttled down to prior to turning on system fans in response to a thermal event, expressed as a percentage.
ForcedThrottle
The processor throttle level to be imposed by the system, expressed as a percentage.
MinThrottle
The minimum processor throttle level, expressed as a percentage.
OverThrottled
A POWER_ACTION_POLICY structure that defines the system power action to initiate in response to a thermal event when processor throttling is unable to adequately reduce the system temperature.
Requirements
Requirement | Value |
---|---|
Minimum supported client | Windows XP [desktop apps only] |
Minimum supported server | Windows Server 2003 [desktop apps only] |
Header | winnt.h (include Windows.h) |