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From: diamond@csl.sony.co.jp (Norman Diamond)
Newsgroups: comp.lang.c
Subject: Re: CTRL(x) macro (was: Re: What is a constant expression)
Message-ID: <11011@riks.csl.sony.co.jp>
Date: 26 Oct 89 01:46:22 GMT
References: <1219@crdos1.crd.ge.COM> <8891@goofy.megatest.UUCP> <3786@solo6.cs.vu.nl> <1422@crdos1.crd.ge.COM> <3802@solo7.cs.vu.nl>
Reply-To: diamond@riks. (Norman Diamond)
Organization: Sony Computer Science Laboratory Inc., Tokyo, Japan
Lines: 26

In article <3802@solo7.cs.vu.nl> maart@cs.vu.nl (Maarten Litmaath) writes:

>In BSD the new tty driver as well as vi, cat -v, ... use ^? to denote DEL.
>Seems pretty normal to me.  According to iscntrl(3) DEL is a control character
>too.

It also seems reasonable to me to think of DEL as a control character.
However, it does seem to be ambiguous in the industry.  That is why
some manuals refer to "control characters and DEL" in order to avoid
ambiguity.

>Too bad it isn't a normal control character; it would have simplified
>things.

Well, it couldn't possibly be a normal control character.  To delete a
typographical error from paper tape, you had to backspace the tape and
punch all 1's (holes) in that column.  If someone decided to make DEL
something other than all 1's, then they would have to invent another
delete that would be all 1's, and it would STILL be ambiguous if the
new delete was really a control character or not.

-- 
Norman Diamond, Sony Corp. (diamond%ws.sony.junet@uunet.uu.net seems to work)
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