Re: changing tetex render engine

Reinhard Kotucha wrote:
>>>>>> "Scott" == Scott J Henson <[email protected]> writes:
>>>>>>             
>
>   > It seems that in the last update to tetex(3) pdfetex was set as
>   > the default render engine for tex.  I am having problems with it
>   > in that it doesn't interpret environment variables in the tex
>   > files.  The old engine(etex) interpreted them properly.  Is there
>   > a way to switch back to etex or get pdfetex to interpret the
>   > environment variables?  Thank you.
>
> It had never been intended that TeX supports environment variables.
>
> I remember that there had been a discussion about it long time ago,
> but I don't remember any details.  Obviously somthing had been changed
> indeed a few years ago, but as I said before, it had never been
> intended to support environment variables.
>   
Do you have a link to this discussion or even what mailing list the 
discussion was held on?

> You can still use environment variables in some situations, for
> instance
>
> \catcode`\$=12
> \input $HOME/envtest.tex
> \bye
>
> Does this work?  This is not a feature of TeX, it's the shell which
> expands $HOME.
>
>   
This does not work in tetex 3 or 2.  I'm having trouble coming up with 
an example file that works as I don't personally use tex.  I'm trying to 
track down this problem for a faculty member and he won't let me 
distribute his files.  As of yet I am, also, unable to produce a valid 
tex file that reproduces the behavior he has under tetex 2 but does not 
work under tetex3.  The specific line that is causing problems is of the 
form:
/input{$HOME/foo.tex}.  He runs this through latex. 

He is also running tcsh.  I'm not entirely clear on how the shell is 
supposed to interpret the environment variables.  Does tex run the file 
through the shell first? 

> I don't think that it is useful to add features like this to TeX.  In
> a few months pdf*tex will have a Lua interpreter built in which will
> give you more convenient access to the environment.
>
> See http://www.lua.org for details about Lua.
>
> However, it would be helpful to have a precise description of your
> problem and a small .tex file which demonstrates your problem.
>
>   
Thanks, I'll inform the faculty member of this.  Do you have an eta on 
when this will be released? 

Thank you.


-- 
Scott Henson
LCSEE Systems Staff
WVU MAE Undergraduate
Ubuntu User