>
>
>-----Original Message-----
>From: netbsd-users-owner@NetBSD.org
>[mailto:netbsd-users-owner@NetBSD.org]On Behalf Of Greg Troxel
>Sent: Tuesday, February 10, 2004 9:45 AM
>To: Johnny Billquist
>Cc: Todd Vierling; Frederick Bruckman; Ben Collver;
>netbsd-users@NetBSD.org
>Subject: Re: Creeping PCism...
>
>
..... 

>because of not only the DEL-is-the-traditional-erase-character reason,
>but because non-PC systems (RSX-11/M, NetBSD on a serial line, etc.)
>expect DEL as the erase character.
>
>I realize this is a matter of opinion, so I won't bother filing a PR.
>
>IMHO NetBSD should pay attention to heritage and tradition, and the
>current behavior violates the POLA for those of us who grew up with
>real terminals.  I'd like to see the defaults changed as I suggested
>above.

ISTR reading somewhere long, long ago that DEL was assigned the role it
has because if you're cutting a paper tape and you make a mistake, the
only thing you can do besides starting over is to overwrite the mistake
with a DEL (all bits).  If everyone then just ignores DELs, all is well.

And everyone did ignore DELs because they were used for timing.  Not all
devices could actually get the carriage returned and the paper fed (CR-LF)
before the next character had to be processed, so sometimes you had to
provide one or more DEL characters after the CR-LF to give the mechanical
stuff a chance.

My earliest exposure to timesharing systems involved ASR-33s.  The PDP-10
at the other end would echo a backslash when it saw a DEL and would remove
the last character it had in its buffer.  This meant you could cut a tape
off-line and then have the ASR-33 read the tape and the host would do the
right thing if it encountered any DELs.

Personally, I suspect the backspace key on a PC keyboard got labeled that
way because the IBM guys, who were used to 3270s, were trying to emulate
the "delete the character to the left" that a DEL (or Rubout, as it was
sometimes called) provided.  But that's just a theory.

Michael D. Spence 
Mockingbird Data Systems, Inc.