gtk-widget-preferred-height-for-width (widget width)

widget -- a gtk-widget object
width -- an integer with the width which is available for allocation

minimum-height -- an integer with the minimum height, or nil
natural-height -- an integer with the natural height, or nil

Retrieves a minimum and natural height of the widget if it would be given the specified width.

The returned request will be modified by the GtkWidgetClass::adjust_size_request virtual method and by any gtk-size-group objects that have been applied. That is, the returned request is the one that should be used for layout, not necessarily the one returned by the widget itself.