Thanks for your so quick reply
I see, it's a good way.
So, I think my file that lists the pdf can be a php script ?
So, it's easy in fact.
How can I crawl only my pdf listing file in shell command ?
$ php [...]/spider.php
http://website/fold1/...../foldx/listingfiles.php
(I don't know how to set the level at one this way...)
May I put a robots.txt in the foldx ?
Where can I get a robots configuration help ?
Thank you very much.