code: func DesktopViewportGet(xu *xgbutil.XUtil) ([]DesktopViewport, error) {
  	coords, err := xprop.PropValNums(xprop.GetProperty(xu, xu.RootWin(),
  		"_NET_DESKTOP_VIEWPORT"))
  	if err != nil {
  		return nil, err
  	}
  
  	viewports := make([]DesktopViewport, len(coords)/2)
  	for i, _ := range viewports {
  		viewports[i] = DesktopViewport{
  			X: int(coords[i*2]),
  			Y: int(coords[i*2+1]),
  		}
  	}
  	return viewports, nil
  }
docs: // _NET_DESKTOP_VIEWPORT get