void rpnstack_init(rpnstack_t *rpnstack);
void rpnstack_free(rpnstack_t *rpnstack);
-void parseCDEF_DS(char *def, rrd_t *rrd, int ds_idx);
+void parseCDEF_DS(const char *def, rrd_t *rrd, int ds_idx);
long lookup_DS(void *rrd_vptr, char *ds_name);
short rpn_compact(rpnp_t *rpnp,rpn_cdefds_t **rpnc,short *count);