Controling other windows on mac os x, is it possible?

i'm working on a software in C, that runs in the background and lists all windows on the desktop periodically, and when a specific word is found (for example por*) this window is closed automatically, but not the whole process.

i'm using "CGSGetOnScreenWindowList" to get a list of all windows, but i have no idea how to close or hide a specific window.

thanks