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From: jacob@gore.com (Jacob Gore)
Newsgroups: comp.text.tex
Subject: Re: Really GENERIC questions on TeX
Message-ID: <1380005@gore.com>
Date: 18 Jul 90 06:45:49 GMT
References: <1048100001@ux1.cso.uiuc.edu>
Reply-To: jacob@gore.com (Jacob Gore)
Organization: Gore Enterprises
Lines: 35

In article <1048100001@ux1.cso.uiuc.edu>, phil@ux1.cso.uiuc.edu writes...
>And if a DVI file
>is truly device independent, why isn't the .dvi file exchanged instead of
>the .tex file?  I know; I might want to modify the document for some reason
>and a .dvi is not (easily) human readable (much like the machine language
>object code output of a compiler).

/ comp.text.tex / dhosek@sif.claremont.edu (Hosek, Donald A.) / Jul 17, 1990 /
> Ever try moving binary files between machines? There are a lot of
> bugbears lying around to trip one up. MVS, CMS and VMS all require
> special system-dependent blocking. You can't e-mail a binary file
> (easily) etc.

Even if these weren't a problem, it's still unreliable to ship .dvi files.
The device they are independent from is the output device, not the
computer.  In particular, a .dvi file has been created with a particular
set of fonts in mind, and those fonts may not be available on another
system.  For example, on machine A the nominal "18-point Computer Modern
Roman font" may be cmr18, while on machine B it may be cmr10 scaled to 18
points.  If I try to print from B a .dvi file created on A, the spacing
will be screwed up.  And people at site C may prefer not to use Computer
Modern fonts at all, and substitute Times-Roman-18 -- no problem if they
have the source, impossible if they just have the binary.

It's much better to ship the sources.

Now within one system, you do get device independence: with appropriate
dvi-to-output-device programs (and font pixel files at appropriate
resolutions), the same .dvi file can be sent to a Postscript printer; a
ImPRESS printer; a LaserJet PCL printer; a NextStep, X, SunTools, MS
Windows or EGA previewer; etc., etc., etc...

Jacob
--
Jacob Gore		Jacob@Gore.Com			boulder!gore!jacob