void gtk_container_foreach ( GtkContainer* container, GtkCallback callback, gpointer callback_data )
callback on each non-internal child of
gtk_container_forall() for details on what constitutes
an “internal” child. For all practical purposes, this function
should iterate over precisely those child widgets that were
added to the container by the application with explicit
It is permissible to remove the child from the
Most applications should use gtk_container_foreach(), rather than gtk_container_forall().
Callback user data.