This data structure extends ns_conn with several useful fields. Values are obtained by calling [ad_conn field_name]. You can access ns_conn fields with the same call, which means you don't need to remember which are provided by AOLserver and which are provided by OpenACS.

Here are some of the more useful fields provided by OpenACS in ad_conn.

• user_id If the visitor is logged in, the user_id is the object_id of the user, zero otherwise.

• package_id If the HTTP request maps to a package instance mounted in the site map, this field is set to the package instance's object id.

• package_url The URL for the requested package.

• node_id The object id of the site node entry itself.

The above list is by no means inclusive, it is just meant to give you an idea of the kind of information made available to a package programmer by the Request Processor.