1How change files are applied for pdftex/pdfetex?
2
3============================= pdftex =============================
4
52) pdftex.ch is generated from
6    ./tie -c pdftex.ch pdftex.web \
7    $(srcdir)/pdftexdir/tex.ch0 \
8    $(srcdir)/tex.ch \
9    $(srcdir)/pdftexdir/tex.ch1 \
10    $(srcdir)/pdftexdir/tex.pch
11
12Input:
13    pdftex.web:
14        pdftex without system-dependent changes
15
16    pdftexdir/tex.ch0:
17        % Change file to assist in creating the web2c-specific change file.
18        % This one comes first, resolves inconsistencies between the
19        % generated pdftex.web and tex.ch
20
21        change the pdftex banner to tex banner, so tex.ch can be applied
22
23    tex.ch:
24        the main web2c-specific (or other system-dependent) change file
25
26    pdftexdir/pdftex.ch:
27
28        % Change file to assist in creating the web2c-specific change file.
29        % This one resolves inconsistencies between tex.ch and tex.pch.
30
31        change the tex banner to pdftex banner (reverse tex.ch0)
32
33Output:
34    pdftex.ch (not pdftexdir/pdftex.ch):
35        additional & system-dependent changes
36