.ltx vs. .tex (was INSTALL.tex)

[Leonhard Möhring <lmoehri@gwdg.de>]

At 10:22 26.11.2002 -0800, you wrote:

> On Tuesday, November 26, 2002, at 02:04 AM, Bill Allombert wrote:
>
> > On Mon, Nov 25, 2002 at 05:45:02PM -0800, Justin C. Walker wrote:
> > > Hi, all,
> > >
> > > I just checked out the Top-of-tree for pari, and I get this complaint
> > > from latex when trying to process INSTALL.tex (this is Mac OS X, both
> > > 10.1 and 10.2):
> > >
> > > This is pdfTeX, Version 3.14159-1.00b-pretest-20020211 (Web2C 7.3.7)
> > > (./INSTALL.tex{/usr/local/teTeX/share/texmf.local/pdftex/config/pdftex.cfg}
> > > LaTeX2e <2001/06/01>
> > > Babel <v3.7h> and hyphenation patterns for american, french, german,
> > > ngerman, d
> > > utch, nohyphenation, loaded.
> > > (./doc/parimacro.tex
> > > ! Undefined control sequence.
> > > l.26   \magnification
> > >                       =\magstephalf
> > > ?
> > >
> > > Any thoughts?
> >
> > This is a TeX file, not a LaTeX file.
> > You must use tex INSTALL.tex. If you latex I get the same warning as you.
> >
> > There is a .ltx extension, while almost never used, would allow to 
> > distinguish between
> > LaTeX and TeX files.
>
> That would help, but as you say, noone uses it.  I need to learn how to 
> distinguish them for myself, clearly.
>
> Regards,
>
> Justin


As a fairly sound guess, if it starts with \documentclass[..]{....}
(or \documentstyle[..]{..} for old LaTeX), and maybe \usepackage{...}
 and has a lot of \begin{...} .... \end{..} clauses, you can be
quite sure it's LaTeX.

But even if you decided it to be LaTeX, you need to check if it 2.09
or 2\epsilon and if you decided it's not LaTeX you can't be sure it's
plain, since there are quite a lot of other macro packages going
around (AMS-TeX springs to my mind).

So even if ppl would use .ltx and .tex you still wouldn't be sure how
to treat those files without having a look at them (or checking some
readme which lies in the vicinity). I doubt that the usage of .ltx would
help the TeX community much, but that's just my two cents.

cheers,

Leonhard