ldc_mem_nextcookie
rv = ldc_mem_nextcookie((ldc_mem_handle_t)dringp->mhdl, cookie);
rv = ldc_mem_nextcookie(mhdl, &dep->payload.cookie[i]);
rv = ldc_mem_nextcookie(ldcp->rx_data_handle,
rv = ldc_mem_nextcookie(tbufp->memhandle,
rv = ldc_mem_nextcookie(dp->data_handle,
rv = ldc_mem_nextcookie(priv_addr->memhandle,
int ldc_mem_nextcookie(ldc_mem_handle_t mhandle, ldc_mem_cookie_t *cookie);