Hello BonnieB,
I see 2 options, but I am sure there are some more.
a. website
USer connects to a website, the site/script check a folder on filesystem and create the .lst as required, then the generated .lst ist used inside the player toward the users request.
b. cron
regular run a script to generte the .lst file, users always access the .lst
I hope this brief advice gives you some ideas ?!
Uwe