Hi Tim,
I'm not familiar with the old ACS's, but in OpenACS you can find a good sample from the installation default home page:
index.adp:
<p>
<if @user_id@ gt 0>
You are currently logged in as @name@ (<a href="/register/">change
login</a>).
</if>
<else>
Start by <b>logging in</b> in the box on the right, using the email
address and password that you have just specified for the
administrator.
</else>
</p>
In the <else> part you could have a link to yoursite.com/register or a form for the registration.
There might be a simple include that would render the login form, but I'm not sure of that. Maybe someone could confirm if this is true?
then, in index.tcl, you have to prepare the data source:
set user_id [ad_get_user_id]
if { $user_id == 0 } {
set user_id ""
}
If you're not familiar with the adp/tcl file pairs, you might want to read the docs for ACS Templating (https://openacs.org/doc/acs-templating/).
Developer note: should user_id be also in acs_page_contract -properties of index.tcl? In the current implementation it doesn't seem to be.