Re: making changes to etex

On Wed, 26 Jan 2005, Johannes Berg wrote:

> Maybe this is a strange question - but I'll ask it anyhow as I
> couldn't really find any documentation on things like this.
>
> I've been making some changes to tex.ch as an experiment. Now,
> however, pdfetex fails to build because it tries to apply tex.ch to
> the pdftex.web (I think). Can anyone enlighten me on how one is
> supposed to make patches to etex?

Check the Makefile in texk/web2c how the dependencies are, e. g. for
etex.ch see make-variable etex_ch_srcs. First, to keep the overview of
what to patch, it helps to create an all-in-one web file named e. g.
etex_.web, using tie:

$ tie -m etex_.web etex.web etex.ch

If you want to experiment only with etex, maybe easiest is to create a
new set of dependencies for some synthetic patch file myetex.ch, e. g.
in the Makefile:

# Tangling (replace the 2 original lines by this:)
etex.p etex.pool: tangle etex.web myetex.ch
        $(TANGLE) etex.web myetex.ch

Then put all your changes into some new file tex.ch2, which comes last
in the additional list of patch files; again in the Makefile:

myetex_ch_srcs = etex.web \
  $(srcdir)/etexdir/tex.ch0 \
  $(srcdir)/tex.ch \
  $(srcdir)/etexdir/tex.ch1 \
  $(srcdir)/etexdir/tex.ech \
  $(srcdir)/etexdir/tex.ch2

myetex.ch: $(myetex_ch_srcs)
        $(TIE) -c myetex.ch $(myetex_ch_srcs)

(Hope it's right; didn't actually try it).

Regards, Hartmut