The easiest way to use XSA as a client is to just download the client kit and use the SimpleClient program in the kit. This program takes a very simple XML file listing the XSA documents and products you want to keep an eye on and every time you run it it prints a simple report showing the changes from the last time it was run.
XSA simple client, version 1.00, XSA version 1.0. Product xmlproc has been updated to version 0.51 Product PyPointers home page has moved to http://www.stud.ifi.uio.no/~larsga/download/python/xml/xptr.html
This is a command-line application, which means that you can run it as a UNIX cron job if you like.
You may already have some software system where all your data about the different products is stored, and may not want to store the list of XSA products separately. If so, you can use the XSA API to develop your own XSA client.
This will allow you to check the information in your own system against that of the XSA documents and allow notification in whatever manner you prefer.
The XSA API is available in Java 1.1 with the client kit.