netif_put
.netif_put = efinet_put,
.netif_put = pxe_netif_put,
.netif_put=ofwn_put,
n = netif_put(d, eh, len);
if (drv->netif_put == NULL)
rv = drv->netif_put(desc, pkt, len);
ssize_t (*netif_put)(struct iodesc *, void *, size_t);
ssize_t netif_put(struct iodesc *, void *, size_t);