RDS_DATA_HDR_SZ
RdsPktSize = UserBufferSize + RDS_DATA_HDR_SZ;
ret = uiomove((uint8_t *)pktp + RDS_DATA_HDR_SZ,
bp1->buf_ds.ds_len = residual + RDS_DATA_HDR_SZ;
datap = ((uint8_t *)(uintptr_t)bp->buf_ds.ds_va) + RDS_DATA_HDR_SZ;
RDS_DATA_HDR_SZ;