pfil_list_dup
pfil_list_dup(ph->ph_in, list_in, NULL);
pfil_list_dup(ph->ph_out, list_out, NULL);
pfil_list_dup(ph->ph_in, list_in, skip_in);
pfil_list_dup(ph->ph_out, list_out, skip_out);
static void pfil_list_dup(const pfil_list_t *, pfil_list_t *,