custom CAD directory/file browser

I have hundreds of CAD drawing files in binary format. Using the strpos() function I can query embedded ASCII info from the CAD files. I display the queried info along with an anchor element to the CAD file in the web browser using a php script. Thus I can give the drawings arbitrary file names but find the file I am looking for from the description in the drawings title block. I can handle that aspect of the project all right, the question is how to handle the directories. If I create an anchor to the directories it drops out of the script and use the browsers file viewing functionality. I think what I need is for the php script to call itself and pass the name of the new directory so the new directory can be queried and displayed. Can I use an anchor element to pass info back to the self same php script? If so how? I can't seem to find my way though this aspect of the project. Point me to a tutorial, give me a clue, or let me struggle on. Thanks -- Regards, Marlin Unruh Sunco Systems Inc. (308) 326-4400