+ * @return #GNUNET_OK on success, #GNUNET_SYSERR on error
+ */
+int
+GNUNET_CONFIGURATION_write (struct GNUNET_CONFIGURATION_Handle *cfg,
+ const char *filename);
+
+
+/**
+ * Write only configuration entries that have been changed to configuration file
+ * @param cfg_default default configuration
+ * @param cfg_new new configuration
+ * @param filename where to write the configuration diff between default and new
+ * @return #GNUNET_OK on success, #GNUNET_SYSERR on error
+ */
+int
+GNUNET_CONFIGURATION_write_diffs (const struct GNUNET_CONFIGURATION_Handle *cfg_default,
+ const struct GNUNET_CONFIGURATION_Handle *cfg_new,
+ const char *filename);
+
+
+/**
+ * Compute configuration with only entries that have been changed
+ *
+ * @param cfg_default original configuration
+ * @param cfg_new new configuration
+ * @return configuration with only the differences, never NULL