#endif
+/**
+ * Initialize a single value through all existing weather levels.
+ *
+ * This function is useful mainly from the command-line.
+ *
+ * @param propname The name of the subproperty to initialized.
+ * @param value The initial value.
+ */
+extern void fgDefaultWeatherValue (const char * propname, double value);
+
+
+/**
+ * Clean up and exit FlightGear.
+ *
+ * This function makes sure that network connections and I/O streams
+ * are cleaned up.
+ *
+ * @param status The exit status to pass to the operating system.
+ */
+extern void fgExit (int status = 0);
+
+
/**
* Move a value towards a target.
*