-char* rrdgetvar(long argc, char **args);
-char* rrdsetvar(long argc, char **args);
-char* rrdsetvarconst(long argc, char **args);
+char* rrdgetvar(long argc, const char **args);
+char* rrdsetvar(long argc, const char **args);
+char* rrdsetvarconst(long argc, const char **args);