diff --git a/bin/feedgnuplot b/bin/feedgnuplot
index 3fe20e9..3ac770a 100755
--- a/bin/feedgnuplot
+++ b/bin/feedgnuplot
@@ -163,8 +163,8 @@ sub interpretCommandline
 
   if ( defined $options{hardcopy} && defined $options{stream} )
   {
-    print STDERR "Warning: since we're making a hardcopy, I'm disabling streaming\n";
-    delete $options{stream};
+    print STDERR "--stream doesn't make sense together with --hardcopy\n";
+    exit -1;
   }
 
   # parse stream option. Allowed only numbers >= 0 or 'trigger'. After this code