Wow. I’m impressed … that pdf is clearly of an nth
generation
photocopy. What contrast ratio?
More seriously, this is a delightful proof point that some cruft is
really cruft.
Your document archaeology work is entertaining and instructive. Thank
you!
Best,
Marc
=====
On Fri, Jun 2, 2023 at 7:04 PM segaloco via TUHS <tuhs(a)tuhs.org> wrote:
While performing my CB-UNIX 2.3 manual separation,
among the many
curious things I came across was this manual page:
https://www.tuhs.org/Archive/Distributions/USDL/CB_Unix/man/man1/dsw.1l.pdf
The dsw(I) pages I've seen in the various UNIX manuals are all for the
interactive delete utility, but make brief mention of the history of
the command being amusing. I've seen some communication on the matter
of the years here, but had never come across a manual page for the
former version of dsw.
In the linked page up there is the actual "delete from switches"
version of dsw. What I find particularly interesting is that the
footer indicates this was printed 8/11/81, but likewise indicates the
command is "PDP-7 local".
This raises a couple of questions:
- Did Columbus ever touch PDP-7 UNIX?
- Did dsw(I) as "delete from switches" ever make it to PDP-11 UNIX?
Even the V1 manual lists the "delete interactively" utility, not this.
- If neither are true, that begs the question of where this page came
from, if there was ever a formalized PDP-7 manual that it would've
descended from or not, etc.
Finally, this page plainly spells out the history of the command in
the bugs section:
"This command was written in 2 minutes to delete a particular file
that managed to get an 0200 bit in its name. It should work by
printing the name of each file in a specified directory and requestion
a 'y' or 'n' answer. Better, it should be an option of rm(1). The
name is mnemonic, but likely to cause trouble in the future."
So the first bug is eventually mitigated by transforming this into the
more familiar dsw. I can't say what the latter means, whether it's a
concern of "dsw" colliding with some reserved word eventually or is
more poking fun at the other folk etymology of "delete s__t work".
In any case, I hadn't seen the etymology explained to this degree in
the mailing list references I found while searching around, so figured
I'd share this analysis.
- Matt G.
P.S. There is mention here that Dennis Ritchie shared the original dsw
manpage at some point
https://www.tuhs.org/pipermail/tuhs/1999-November/001203.html however
the link in question appears to be dead. In any case, the source for
the PDP-7 version is in that email if anyone wants to look at it,
although looks to be the same as what is in the archive.