+int main(int argc, char **argv);
+
+/*
+ * HOSTNAME_INSTANCE may not be defined at this point.
+ * We define it locally if it is needed...
+ *
+ * If CLIENT_HOST_PRINCIPLE is defined as HOSTNAME_INSTANCE
+ * then local host is the client host principle.
+ */
+#ifndef HOSTNAME_INSTANCE
+# define HOSTNAME_INSTANCE "localhost"
+#endif
+
+#ifndef KEYFILE
+# define KEYFILE "id_rsa"
+#endif