filter.path to a path on the child model of filter. That is,
filter.path points to a location in filter. The returned path will
point to the same location in the model not being filtered. If filter.path
does not point to a location in the child model, NULL is returned.gtkTreeModelFilterConvertPathToChildPath(object, filter.path)objectfilter.pathGtkTreePath to convert.GtkTreePath] A newly allocated GtkTreePath, or NULL.