PBT_APMRESUMECRITICAL event

[PBT_APMRESUMECRITICAL is available for use in the operating systems specified in the Requirements section. Support for this event was removed in Windows Vista. Use PBT_APMRESUMEAUTOMATIC instead.]

Notifies applications that the system has resumed operation. This event can indicate that some or all applications did not receive a PBT_APMSUSPEND event. For example, this event can be broadcast after a critical suspension caused by a failing battery.

A window receives this event through the WM_POWERBROADCAST message. The wParam and lParam parameters are set as described following.

LRESULT 
CALLBACK 
WindowProc( HWND   hwnd,    // handle to window
            UINT   uMsg,    // WM_POWERBROADCAST
            WPARAM wParam,  // PBT_APMRESUMECRITICAL
            LPARAM lParam); // zero

Parameters

hwnd

A handle to window.

uMsg

wParam

lParam

Reserved: must be zero.

Return value

No return value.

Remarks

Because a critical suspension occurs without prior notification, resources and data previously available may not be present when the application receives this event. The application should attempt to restore its state to the best of its ability. While in a critical suspension, the system maintains the state of the DRAM and local hard disks, but may not maintain net connections. An application may need to take action with respect to files that were open on the network before critical suspension.

Requirements

See also

• System Wake-up Events
• Power Management Events
• WM_POWERBROADCAST