vn_stat
error = vn_stat(vrtmp, &st, td->td_ucred);
error = vn_stat(vp, st, nd->nl_cred);
error = vn_stat(vp, &sb, td->td_ucred);
error = vn_stat(vp, sb, cred);
int vn_stat (struct vnode *vp, struct stat *sb, struct ucred *cred);
error = vn_stat(vp, sb, cred);