Inserts a new row after @sibling. If @sibling is %NULL, then the row will be
prepended to the beginning of the list. @iter will be changed to point to
this new row. The row will be empty after this function is called. To fill
in values, you need to call gtk_list_store_set() or gtk_list_store_set_value().
Inserts a new row after @sibling. If @sibling is %NULL, then the row will be prepended to the beginning of the list. @iter will be changed to point to this new row. The row will be empty after this function is called. To fill in values, you need to call gtk_list_store_set() or gtk_list_store_set_value().