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From: mjm@eleazar.dartmouth.edu (Andy Behrens)
Newsgroups: comp.periphs.printers
Subject: Re: How do you send NUL to a printer?
Message-ID: <1991May31.175225.7882@dartvax.dartmouth.edu>
Date: 31 May 91 17:52:25 GMT
References: <2291@twg.bc.ca>
Sender: steve@dartvax.dartmouth.edu (Steve Campbell)
Reply-To: andyb@coat.com (Andy Behrens)
Organization: Burlington Coat Factory
Lines: 35

bill@twg.bc.ca (Bill Irwin) writes:
>  [I have been trying to send a NUL to a printer using]
>  echo -n "^[C\000011"
>  
>  When this is directed to a file and viewed with vi, I get:
>  
>  ^[C11
> 
>  Is the NUL supposed to show in vi?  When this is sent to the
>  printer it behaves as though it was sent the Lines setting
>  command, without the NUL.  

Vi won't show you the NUL characters even though they're in the file, but 'od -c' will.  

However, that isn't where your problem lies.  Many terminal drivers
will discard NUL characters on output.  You can fool them by sending
\200 instead: it won't be discarded, but the high-order bit will be
deleted before the printer sees it.

Try 
	echo -n "^[C\020011"

instead.


--
If you've got a hammer,			       If the only tool you have
find a nail.				    is a hammer, you tend to see
(George Bush, January 29, 1991)			every problem as a nail.
							(Abraham Maslow)
+-------------------+
|  Andy Behrens     |                   or: andyb%coat.com@dartmouth.edu
|  andyb@coat.com   |                    bitnet: andyb%coat.com@dartcms1
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