diff --git a/kwsys_ios_iostream.h.in b/kwsys_ios_iostream.h.in
index 77aed4610913ac907447ab61cdce10d4cb7d1508..c3a3f87e90b8b713d8453d339eed4798ecc66463 100644
--- a/kwsys_ios_iostream.h.in
+++ b/kwsys_ios_iostream.h.in
@@ -64,6 +64,8 @@
 #if !@KWSYS_NAMESPACE@_IOS_USE_SSTREAM
 namespace @KWSYS_NAMESPACE@_ios
 {
+  typedef int streamsize;
+  typedef int streamoff;
   using @KWSYS_NAMESPACE@_ios_namespace::ostream;
   using @KWSYS_NAMESPACE@_ios_namespace::istream;
   using @KWSYS_NAMESPACE@_ios_namespace::ios;