vs_columns
size_t vs_columns(SCR *, char *, recno_t, size_t *, size_t *);
(void)vs_columns(sp, tp->lb, tp->lno, &cno, &olen);
(void)vs_columns(sp, tp->lb, tp->lno, &cno, &nlen);
(void)vs_columns(sp,
cnt = vs_columns(sp, NULL, LNO, &CNO, NULL);
cols = vs_columns(sp, NULL, lno, cnop, NULL);