IConsolePowerSink::OnPowerBroadcast method (mmc.h)

The OnPowerBroadcast method processes WM_POWERBROADCAST notification messages related to the computer's power management.

Syntax

HRESULT OnPowerBroadcast(
  [in]  UINT    nEvent,
  [in]  LPARAM  lParam,
  [out] LRESULT *plReturn
);

Parameters

[in] nEvent

The power broadcast event identifier. The identifier is one of the following values.

PBT_APMBATTERYLOW

Battery power is low.

PBT_APMOEMEVENT

OEM-defined event occurred.

PBT_APMPOWERSTATUSCHANGE

Power status has changed.

PBT_APMQUERYSUSPEND

Request for permission to suspend.

PBT_APMQUERYSUSPENDFAILED

Suspension request denied.

PBT_APMRESUMEAUTOMATIC

Operation resuming automatically after event.

PBT_APMRESUMECRITICAL

Operation resuming after critical suspension.

PBT_APMRESUMESUSPEND

Operation resuming after suspension.

PBT_APMSUSPEND

System is suspending operation.

[in] lParam

Function-specific data. For most events, this parameter is reserved and not used. However, if nEvent is one of the resume events (PBT_APMRESUME*), the lParam parameter can specify the PBTF_APMRESUMEFROMFAILURE flag. This flag indicates that a suspend operation failed after the PBT_APMSUSPEND event was broadcast.

[out] plReturn

On return, the snap-in's response to the broadcast event. Generally, set *plReturn to TRUE. The exception is when nEvent is PBT_APMQUERYSUSPEND. To allow the computer suspension to continue in response to the PBT_APMQUERYSUSPEND event, set *plReturn to TRUE; to deny the computer suspension, set *plReturn to BROADCAST_QUERY_DENY. A snap-in that permits computer suspension should perform necessary suspension preparations before returning from this method.

Return value

If successful, the return value is S_OK. Other return values indicate an error code.

Requirements

See also

WM_POWERBROADCAST