[TUHS] early Unix terminals (was: Re: Curly braces: An evolution of UNIX and C)

[Warner Losh via TUHS]

On Wed, May 20, 2026, 7:22 PM G. Branden Robinson via TUHS <tuhs at tuhs.org>
wrote:

> At 2026-05-20T17:23:22-0700, Larry McVoy via TUHS wrote:
> > > Everyone's experience was different.  The Unix system I used in a
> > > lab at Princeton only had the ASR-33 TTY.  The one I ran at Yale had
> > > the TTY console and a bunch of unique homebrewed bitmap terminals
> > > that I wrote up in an article in Software Practice and Experience.
> >
> > I don't have a lot to add to this other than there was some terminal,
> > I think a VT-something, that had the standard 80x24 but it had a 25th
> > line that was the status line.
>
> Yup, that was a DEC VT220 or maybe 320 feature.  (Others had them, but
> DEC's VT series wagged a great deal of the dog.)
>
> https://vt100.net/docs/tp83/chapter4.html
>
> It's possible that the status line on the 25th row didn't become
> entrenched until the DEC VT320, or was not host-programmable until then;
> Thomas Dickey's terminfo database exhibits an "hs" capability for the
> "vt320" terminal type description but not for "vt220".
>
> https://invisible-island.net/ncurses/man/terminfo.5.html
> https://invisible-island.net/ncurses/terminfo.src.html
>
> If the database is inaccurate, maybe someone can help Thomas improve it.
>
> > I think BSD had a Ctrl-T that dug info out of the kernel and displayed
> > it on that line.
>
> Yup.  With that factoid, not long ago I surprised a colleague at UNSW
> who was much closer to being Present at the Creation than I could have
> been.  He knew Research Unix backwards and forwards, but not BSD.
>

Close. ^T didn't display in that extra line. The tty driver didn't know
terminal types... unless it was a local hack.

Warner

> When you are in a terminal room with 30-40 people on a 4MB VAX, Ctrl-T
> > was your friend.
>
> Unless _everybody_ learns that trick and exhibits undergrad patience,
> whacking it several times a second, and all those traps into the kernel
> just make the problem worse.  ;-)
>
> Regards,
> Branden
>