--- a/src/ChangeLog	Wed Mar 08 20:17:38 2006 +0000
+++ b/src/ChangeLog	Wed Mar 08 20:31:26 2006 +0000
@@ -1,3 +1,11 @@
+2006-03-08  John W. Eaton  <jwe@octave.org>
+
+	* oct-stream.cc (octave_stream::stream_ok): Move definition here,
+	from oct-stream.h.  New arg, warn.  If warn is true and stream is
+	invalid, print warning.
+	(octave_stream::error): Always avoid warning message from
+	stream_ok.  Return "invalid stream object" if stream is not ok.
+
 2006-03-08  David Bateman  <dbateman@free.fr>
 
 	* ov-mapper.cc (SPARSE_MAPPER_LOOP_2): Change nnz to nz to remove 

--- a/src/oct-stream.cc	Wed Mar 08 20:17:38 2006 +0000
+++ b/src/oct-stream.cc	Wed Mar 08 20:31:26 2006 +0000
@@ -3754,9 +3754,9 @@
 std::string
 octave_stream::error (bool clear, int& err_num)
 {
-  std::string retval;
-
-  if (stream_ok ("ferror", false))
+  std::string retval = "invalid stream object";
+
+  if (stream_ok ("ferror", false, false))
     retval = rep->error (clear, err_num);
 
   return retval;
@@ -3833,6 +3833,27 @@
   return retval;
 }
 
+bool
+octave_stream::stream_ok (const std::string& who, bool clear, bool warn) const
+{
+  bool retval = true;
+
+  if (rep)
+    {
+      if (clear)
+	rep->clear ();
+    }
+  else
+    {
+      if (warn)
+	::warning ("%s: attempt to use invalid I/O stream", who.c_str ());
+
+      retval = false;
+    }
+
+  return retval;
+}
+
 octave_stream_list *octave_stream_list::instance = 0;
 
 bool

--- a/src/oct-stream.h	Wed Mar 08 20:17:38 2006 +0000
+++ b/src/oct-stream.h	Wed Mar 08 20:31:26 2006 +0000
@@ -591,20 +591,8 @@
   // The actual representation of this stream.
   octave_base_stream *rep;
 
-  bool stream_ok (const std::string& who, bool clear = true) const
-    {
-      bool retval = true;
-
-      if (rep)
-	{
-	  if (clear)
-	    rep->clear ();
-	}
-      else
-	retval = false;
-
-      return retval;
-    }
+  bool stream_ok (const std::string& who, bool clear = true,
+		  bool warn = true) const;
 
   void invalid_operation (const std::string& who, const char *rw)
     {