diff --git a/include/object-db-file.h b/include/object-db-file.h
index dea8582..1eb1ef8 100644
--- a/include/object-db-file.h
+++ b/include/object-db-file.h
@@ -4,8 +4,6 @@
 #include "object-db.h"
 #include <stdio.h>
 #include <fstream>
-#include <ifstream>
-#include <ofstream>
 #include <sstream>
 #include <deque>
 #include <boost/thread/locks.hpp>
@@ -50,7 +48,7 @@
   typedef boost::unique_lock<Mutex> ULock;
 
   ObjectDBFile(const string &filename);
-  virtual ~ObjectDBFile(){}
+  virtual ~ObjectDBFile();
 
   // reserve the "address" table for n COs; must reserve before
   // write anything (unless reserved quota has not be consumed yet)
@@ -149,4 +147,7 @@
 void
 readBytes(istream &in, Bytes &bytes);
 
+char *
+head(const Bytes &bytes);
+
 #endif
diff --git a/include/object-db.h b/include/object-db.h
index 7daa37c..207e0b3 100644
--- a/include/object-db.h
+++ b/include/object-db.h
@@ -35,7 +35,7 @@
 
   // size in terms of number of COs
   virtual int
-  size() = 0 const;
+  size() = 0;
 
 };