I want to prevent the monitor from going to sleep (the windows setting, not the monitor setting). I am using c++. What call do I make?
class KeepDisplayOn
{
public:
KeepDisplayOn()
{
mPrevExecState = ::SetThreadExecutionState(ES_DISPLAY_REQUIRED | ES_SYSTEM_REQUIRED | ES_CONTINUOUS);
::SystemParametersInfo(SPI_GETSCREENSAVETIMEOUT, 0, &mPrevScreenSaver, 0);
::SystemParametersInfo(SPI_SETSCREENSAVETIMEOUT, FALSE, NULL, 0);
}
~KeepDisplayOn()
{
::SystemParametersInfo(SPI_SETSCREENSAVETIMEOUT, mPrevScreenSaver, NULL, 0);
::SetThreadExecutionState(mPrevExecState);
}
private:
UINT mPrevScreenSaver;
EXECUTION_STATE mPrevExecState;
};
A simpler way that doesn't modify global system state like the first response does:
In your window procedure, add a handler for WM_SYSCOMMAND
. When wParam is SC_MONITORPOWER
, return 0 instead of deferring to DefWindowProc
. (When wParam is any other value, make sure you either handle the message or pass it to DefWindowProc
. Otherwise the user will have difficulty adjusting your window at runtime.)
SetThreadExecutionState(ES_DISPLAY_REQUIRED|ES_CONTINUOUS);
Wiggle the mouse every minute or so.
mouse_event(MOUSEEVENTF_MOVE,1,0,0,0);
mouse_event(MOUSEEVENTF_MOVE,-1,0,0,0);
Sleep(60000);