C++ - is display off?

I'm trying to figure out whether the display is off. Just to clarify what I mean by display is off; windows has the Turn off the display options in the power options.

I've looked at this MSDN page, and noticed SC_MONITORPOWER parameter which "Sets the state of the display ". Is there any way to get the state of the display?

Notes

I need to support all windows version >= XP