cpc_buf_get
(void) cpc_buf_get(cpc, buf, i, &val);
(void) cpc_buf_get(cpc, buf, i, &val);
(void) cpc_buf_get(cpc, buf, i, &val);
extern int cpc_buf_get(cpc_t *cpc, cpc_buf_t *buf, int index, uint64_t *val);