Retrieve Trace File Name During On-Line Session

I am developing a page that allows a user to browse, download or delete their online trace file. (System administrators don't like to give users direct delete access to the LOGS folder).

I am using PeopleTools 8.51 against SQL Server 2008 R2. I built a work record that contains the following RowInit PeopleCode. The purpose of the code is to discover the name of the trace file:

Local ApiObject &api_session;

Local String &str;

/** Get Session ApiObject **/

&api_session = %Session;

&str = &api_session.TraceSettings.TraceFile;

MessageBox(0, "", 0, 0, "Trace File: " | &str);

The MessageBox returns an empty value. Can anyone help?