gtk:icon-factory-lookup (factory stock-id)

factory -- a gtk:icon-factory object
stock-id -- a string with an icon name

The gtk:icon-set instance of stock-id.

Looks up stock-id in the icon factory, returning an icon set if found, otherwise nil. For display to the user, you should use the gtk_style_lookup_icon_set() function on the GtkStyle object for the widget that will display the icon, instead of using this function directly, so that themes are taken into account. The gtk:icon-factory-lookup function has been deprecated since version 3.10 and should not be used in newly written code. Use the gtk:icon-theme class instead.