px_ib_alloc_ih
extern px_ih_t *px_ib_alloc_ih(dev_info_t *rdip, uint32_t inum,
ih_p = px_ib_alloc_ih(rdip, hdlp->ih_inum, hdlp->ih_cb_func,
ih_p = px_ib_alloc_ih(rdip, hdlp->ih_inum,