Use one of the Win32:: modules, like Win32::API, and then make the appropriate API call (I just happen to know it's GetForegroundWindow cause I use AMMO SDK)

update: I just remembered Win32::GuiTest ^{( * )} .

MJD says you can't just make shit up and expect the computer to know what you mean, retardo! I run a Win32 PPM repository for perl 5.6x+5.8x. I take requests. ** The Third rule of perl club is a statement of fact: pod is sexy.