[tex-live] Where is the master control switch?

[Frank Küster]

Ken Brooks <kenb at rpath.com> wrote:

> I have read the kpathsea manual, and the original texmf.cnf, and I am
> left with a few questions.  I'm a little unclear on what has to take
> place at compile time vs. what is established at runtime:
>
> 1. Does a texmf.cnf need to be available at compile time when the
> various tex programs are built?  In general, does the texmf tree as a
> whole need to be installed for best results before compiling tex programs?

I cannot speak for all programs in TeXlive, but for the basic ones it is
not needed.  More specifically, for all that are also in teTeX 3.0; we
build our Debian package of the binaries without having the texmf tree
installed. 

> 2. There are so many choices.  I'm wondering about best practices for 
> handling the numerous variables named in all-caps, found in texmf.cnf 
> and elsewhere: TEXMFMAIN, TEXMFLOCAL, TEXMFDBS, VARTEXFONTS, etc.
> Should these best be handled as
> - command line parameters to "configure"?
> - environment variables present when configure is run?
> - entries in texmf.cnf (presuming that TEXMFCNF has been set already)
> - or, environment variables present at runtime?

I don't think that you can pass them to configure; at least its --help
output does not tell this.  What I would do is patch
Build/source/texk/kpathsea/texmf.in (this is the source file for paths.h
which sets the compile-time default).  But in fact the only thing that
is set at configure time is the search path for texmf.cnf.  All the
others can (and should) be set at runtime in texmf.cnf.

> 3. I have already observed that setting TEXMFMAIN as an environment
> variable at runtime is inadequate.  How many such variables would need
> to be separately set at runtime to make things work right, if the texmf
> tree is not where it was expected to be at compile time?

No idea, and it probably depends on the program that is called.  But I
think you don't need this:  All you have to make sure is that texmf.cnf
is found.  Better do this by changing texmf.in.

Regards, Frank
-- 
Frank Küster
Single Molecule Spectroscopy, Protein Folding @ Inst. f. Biochemie, Univ. Zürich
Debian Developer (teTeX/TeXLive)