12 Apr
2024
12 Apr
'24
7:29 a.m.
On Mon, Apr 8, 2024, at 15:51, Mary Ann Horton wrote:
On 4/8/24 08:18, arnold(a)skeeve.com wrote:
That makes me wonder about the timeline compared to the other tenex-inspired BSD-ism I’m
happy for: tcsh.
History here:
https://github.com/tcsh-org/tcsh/blob/master/tcsh.man.in#L10239
<https://github.com/tcsh-org/tcsh/blob/c416b8588e4012f6f90cd82262e7d30afe06bbbd/tcsh.man.in#L10239>
Dan Cross <crossd(a)gmail.com> wrote:
Vi had ^W for word erase long before the tty driver. It's documented in
2BSD.
I think it appeared in the tty driver as part of the new tty driver, around 4.1C. The 4.2
stty(1) documents that you can set werase but only with the new tty driver.
Personally I fondly recalled it from Tenex and wished for it in UNIX. I can't recall
if I lobbied for it or if anyone heard me.
Chambers and Quarterman noted the new tty driver's presence in 4.1C.
https://gunkies.org/wiki/UNIX*_System_V_and_4.1C_BSD
> 2.2.5 Ioctls The ioctl system call is essentially
> identical in the two systems. The interesting differences
> are in the terminal driver ioctls. Both drivers utilize the
> ``line discipline'' notion, allowing dynamic choice among
> several protocols by the user process.
>
> Berkeley offers several new features in 4.1C BSD over
> the V7 terminal driver. Some of these are accessed as a new
> line discipline (the ``new tty'' discipline), while a few
> others are implemented as additional ioctl calls. I wonder if anyone can shed any light on the
timing and rationale for
the introduction of “word erase” functionality to the kernel terminal
driver. My surface skim earlier leads me to believe it came to Unix
with 4BSD, but it was not reincorporated into 8th Edition or later,
nor did it make it to Plan 9 (which did incorporate ^U for the "line
kill" command). TOPS-20 supports it via the familiar ^W, but I'm not
sure about other PDP-10 OSes (Lars?). Multics does not support it.
VMS does not support it.
What was the proximal inspiration? The early terminal drivers seem to
use the Multics command editing suite (`#` for erase/backspace, `@`
for line kill), though at some point that changed, one presumes as
TTYs fell out of favor and display terminals came to the fore.
- Dan C.
My memory jibes with this -- through V7 defaults were # and @, and BSD
changed to ^H / DEL and ^U. ^W was a BSD thing, probably inspired by
TOPS-10.