Help With Adding A New Tab to 'notebook'

[Jason Dempsey <jasondempsey insightbb com>]

Ok: i now have this:

void
on_button1_clicked                     (GtkButton       *button,
                                        gpointer         user_data)
{
void 
gtk_notebook_insert_page (GtkNotebook *notebook,
                                          GtkNotebook *child,
                                          GtkNotebook *tab_label,
                                                  gint -1);
}

 and i get this error:

callbacks.c: In function `on_button1_clicked':
callbacks.c:363: parse error before '-' token
make[2]: *** [callbacks.o] Error 1

Help!