[texhax] Detecting in-document-ness?

[Douglas Lewan]

All,

I'm writing a book and, while writing it, would typically prefer to be 
able to view the current chapter on its own.

Is there a standard/common way to detect if LaTeX is already in a 
document and only if not, then do the normal start of document 
processing, like \documentclass{} and \begin{document} (and maybe a few 
other things that I'll need)?

Thanks.

-- 
,Doug
Douglas Lewan
email: d_lewan2000 at yahoo.com <mailto:d_lewan2000 at yahoo.com>
cell: 908 7207 908

         Brain fried; core dumped.