diff --git a/ChangeLog b/ChangeLog
index 06a13369..6fe57704 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,11 @@
 2000-01-12  Martin Baulig  <martin@home-of-linux.org>
 
+	* include/glibtop/errors.h (GLIBTOP_ERROR_NO_BACKEND_OPENED):
+	New error constant.
+
+	* lib/lib.pl (glibtop_get_<feature>_l): Don't dump core when there
+	is no backend opened, but return GLIBTOP_ERROR_NO_BACKEND_OPENED.
+
 	* include/glibtop/backend.h (glibtop_backend): Added `_priv_module'
 	pointer (type glibtop_backend_module). Made the `info' field const
 	since this now points to gmodule loaded memory
diff --git a/include/glibtop/errors.h b/include/glibtop/errors.h
index 7ee6c35d..56f5b9a7 100644
--- a/include/glibtop/errors.h
+++ b/include/glibtop/errors.h
@@ -46,10 +46,11 @@ BEGIN_LIBGTOP_DECLS
 
 #define GLIBTOP_ERROR_NO_SUCH_BACKEND		10
 #define GLIBTOP_ERROR_NOT_IMPLEMENTED		11
+#define GLIBTOP_ERROR_NO_BACKEND_OPENED		12
 
-#define GLIBTOP_ERROR_DEMARSHAL_ERROR		12
+#define GLIBTOP_ERROR_DEMARSHAL_ERROR		13
 
-#define GLIBTOP_MAX_ERROR			13
+#define GLIBTOP_MAX_ERROR			14
 
 char *
 glibtop_get_error_string_l (glibtop *server, unsigned error_number);
diff --git a/lib/lib.pl b/lib/lib.pl
index a5cd85a8..3af22a8e 100755
--- a/lib/lib.pl
+++ b/lib/lib.pl
@@ -158,6 +158,9 @@ sub output {
     }
 
     $sysdeps_code = sprintf
+      ("\tif (!server->_priv)\n\treturn -GLIBTOP_ERROR_NO_BACKEND_OPENED;\n\n");
+
+    $sysdeps_code .= sprintf
       ("\tfor (list = server->_priv->backend_list;\n\t     list; list = list->next) {\n\t\tglibtop_backend *backend = list->data;\n\n\t\tif (!backend->info || !backend->info->call_vector)\n\t\t\tcontinue;\n\n\t\tif (backend->info->call_vector->%s) {\n", $feature);
 
     if ($line_fields[3] eq '') {