diff --git a/man3/xdr.3 b/man3/xdr.3
index ea6359787..83f668dc9 100644
--- a/man3/xdr.3
+++ b/man3/xdr.3
@@ -460,8 +460,8 @@ integers and their external representations.
 This routine returns one if it succeeds, zero otherwise.
 .PP
 .nf
-.BI "bool_t xdr_union(XDR *" xdrs ", int *" dscmp ", char *" unp ,
-.BI "                 struct xdr_discrim *" choices ,
+.BI "bool_t xdr_union(XDR *" xdrs ", enum_t *" dscmp ", char *" unp ,
+.BI "                 const struct xdr_discrim *" choices ,
 .BI "                 xdrproc_t " defaultarm ");     /* may equal NULL */"
 .fi
 .IP