🚀 go-pugleaf

In article <5mf90e$pkv@mozo.cc.purdue.edu>,
	abe@cc.purdue.edu (Vic Abell) writes:
> richard@cogsci.ed.ac.uk (Richard Tobin) writes:
> 
>>I suppose I shouldn't bring this one up, since there's probably no
>>documentary evidence, but what about dsw (the predecessor to rm -i)?
>>I seem to recall hearing that it was "delete using switches", where
>>the switches were the ones on the front panel.  Its etymology was
>>described as "amusing", and a comment that the name was "ill-advised"
>>had been removed by sixth edition.
> 
> Dsw stood for the Russian "goodbye" -- das v'dania.  (Please pardon
> my mangling of the Cyrillic transliteration.)

"Delete From Switch Register" is the correct interpretation.

The background is that Ken Thompson created a file whose name
could not be typed in.  So the original dsw command appeared.
It went through the directory, displaying each file name for a few
seconds.  After the delay, it looked at the status of one switch of the
switch register (a row of switches on the front of the PDP-11),
and if on would remove the file, othewise leave it.  Repeat for
each file.  By the time I came across it, that functionality had
vanished and it was keyboard driven.

Lindsay