diff --git a/src/rrd_format.h b/src/rrd_format.h
index b8f079055516fa558caec9dce61cf2587f84c4cc..7f974cb62deb9dc5d8a734ed153b27cbb95f3b45 100644 (file)
--- a/src/rrd_format.h
+++ b/src/rrd_format.h
#ifndef _RRD_FORMAT_H
#define _RRD_FORMAT_H
+/*
+ * _RRD_TOOL_H
+ * We're building RRDTool itself.
+ *
+ * RRD_EXPORT_DEPRECATED
+ * User is requesting internal function which need this struct. They have
+ * been told that this will change and have agreed to adapt their programs.
+ */
+#if !defined(_RRD_TOOL_H) && !defined(RRD_EXPORT_DEPRECATED)
+# error "Do not include rrd_format.h directly. Include rrd.h instead!"
+#endif
+
#include "rrd.h"
/*****************************************************************************