nfsm_disct
if ((error = nfsm_disct(mdp, dposp, NFSX_FATTR(v3), t1, &cp2)) != 0)
error = nfsm_disct(&info->md, &info->dpos, bytes, n, &cp2);
int nfsm_disct(struct mbuf **mdp, caddr_t *dposp, int siz,