[besson3c]

By default .htaccess protected directories do not seek out htpasswd generated files to authenticate against. Rather, if you set your htaccess file to:

Code:
require valid-user

any valid account on that system (generated through the Accounts pref pane) will have access to this directory.

How does OS X do this? How would I go about setting this up on other Unix platforms? I'd like to manage access to htaccess protected directories at the system level (i.e. a password change at the system level affecting access to htaccess protected directories).

Does this make sense?

[Millennium]

My guess is that it goes through /etc/passwd, which is a mirror of the NetInfo user database.

That said, you really shouldn't do this, unless you're using Digest authentication. Basic authentication sends passwords over the network in what amounts to cleartext (it uses Base64, which is about as strong as ROT13). Use Digest authentication if you have to use anything.