+
+#ifdef UNION
+{
+ extern int (**union_vnodeop_p)();
+ extern struct vnode *union_dircache __P((struct vnode *));
+
+ if ((uap->count == auio.uio_resid) &&
+ (vp->v_op == union_vnodeop_p)) {
+ struct vnode *lvp;
+
+ lvp = union_dircache(vp);
+ if (lvp != NULLVP) {
+ struct vattr va;
+
+ /*
+ * If the directory is opaque,
+ * then don't show lower entries
+ */
+ error = VOP_GETATTR(vp, &va, fp->f_cred, p);
+ if (va.va_flags & OPAQUE) {
+ vput(lvp);
+ lvp = NULL;
+ }
+ }
+
+ if (lvp != NULLVP) {
+ error = VOP_OPEN(lvp, FREAD, fp->f_cred, p);
+ VOP_UNLOCK(lvp);
+
+ if (error) {
+ vrele(lvp);
+ return (error);
+ }
+ fp->f_data = (caddr_t) lvp;
+ fp->f_offset = 0;
+ error = vn_close(vp, FREAD, fp->f_cred, p);
+ if (error)
+ return (error);
+ vp = lvp;
+ goto unionread;
+ }
+ }
+}
+#endif /* UNION */
+
+ if ((uap->count == auio.uio_resid) &&
+ (vp->v_flag & VROOT) &&
+ (vp->v_mount->mnt_flag & MNT_UNION)) {
+ struct vnode *tvp = vp;
+ vp = vp->v_mount->mnt_vnodecovered;
+ VREF(vp);
+ fp->f_data = (caddr_t) vp;
+ fp->f_offset = 0;
+ vrele(tvp);
+ goto unionread;
+ }
+ error = copyout((caddr_t)&loff, (caddr_t)uap->basep, sizeof(long));