[plt-scheme] Web server authorisation

Basically, you set up a single file of passwords for the site, in
which you can specify patterns of paths to protect.  You also specify
where you want this file to reside.  The location of the file goes in
the configuration file under the tag PASSWORD-AUTHENTICATION with
PATHS, and the password file itself is an sexp.  The default is the
file named "passwords" in the root directory.  Here's an example of a
passwords file:

(("PADL Reviews"
   "/Details(/.*)?"
   (subpc "Hugo")
   (pc "Boss")))

This says

- "/Details..." is the set of paths to protect,
- "PADL Reviews" will be the prompt for their password,
- username `subpc' has password "Hugo", and
- username `pc' has password "Boss"

So each path/prompt pair can have several username/password entries;
in turn, you an have several path/prompt entries by extending the
s-expression in the obvious way (note the outer "((").

Does that help?

Shriram