Whenever a LATEX document starts with \documentstyle
, rather than
with \documentclass
, LATEX assumes that it is a LATEX 2.09
document and therefore processes it in `compatibility mode'. This
does the following:
\@compatibilitytrue
;
latex209.def
;
latex209.cfg
if it exists.
The LATEX 2.09 set-up allowed the format itself to be customised. When making the format with iniTEX, the process ended with this request:
Input any local modifications here.
If your site did input any modifications at that point then the
LATEX2e `compatibility mode' will not fully emulate LATEX 2.09
as installed at your site. In this case you should put all
these `local modifications' into a file called latex209.cfg
and put
this file in the default input path at your site. These `local
modifications', although not stored in the format, will then be loaded
before any old-style document is processed. This should ensure that
you can continue to process any old documents that made use of this
local customisation.