+ return vconn->version ? vconn->version : -1;
+}
+
+/* By default, a vconn accepts only OpenFlow messages whose version matches the
+ * one negotiated for the connection. A message received with a different
+ * version is an error that causes the vconn to drop the connection.
+ *
+ * This functions allows 'vconn' to accept messages with any OpenFlow version.
+ * This is useful in the special case where 'vconn' is used as an rconn
+ * "monitor" connection (see rconn_add_monitor()), that is, where 'vconn' is
+ * used as a target for mirroring OpenFlow messages for debugging and
+ * troubleshooting.
+ *
+ * This function should be called after a successful vconn_open() or
+ * pvconn_accept() but before the connection completes, that is, before
+ * vconn_connect() returns success. Otherwise, messages that arrive on 'vconn'
+ * beforehand with an unexpected version will the vconn to drop the
+ * connection. */
+void
+vconn_set_recv_any_version(struct vconn *vconn)
+{
+ vconn->recv_any_version = true;