SetSystemPowerState

[This is preliminary documentation and subject to change.]

The SetSystemPowerState function suspends the system by shutting power down. Depending on the ForceFlag parameter, the function either suspends operation immediately or requests permission from all applications and device drivers before doing so.

BOOL SetSystemPowerState(
  BOOL fSuspend,  
  BOOL fForce     
);
 

Parameters

fSuspend

Ignored.

fForce

Forced suspension. If TRUE, the function sends a PBT_APMSUSPEND message to each application and driver, then immediately suspends operation. If FALSE, the function sends a PBT_APMQUERYSUSPEND message to each application to request permission to suspend operation.

Return Values

If power has been suspended and subsequently restored, the return value is nonzero.

If the system was not suspended, the return value is zero. To get extended error information, call GetLastError.

Remarks

If any application or driver denies permission to suspend operation, the function sends a PBT_APMQUERYSUSPENDFAILED message to each application and driver. If power is suspended, this function returns only after system operation is resumes and related WM_POWERBROADCAST messages have been sent to all applications and drivers.

QuickInfo

  Windows NT: Requires version 5.0 or later.
  Windows: Requires Windows 95 or later.
  Windows CE: Unsupported.
  Header: Declared in winbase.h.
  Import Library: Use kernel32.lib.

See Also

Power Management Overview, Power Management Functions, PBT_APMQUERYSUSPEND, PBT_APMQUERYSUSPENDFAILED, PBT_APMSUSPEND, WM_POWERBROADCAST