How do search engines react to the "open/save" dialog?

if they ignore it, how to detect that the visitor is a search engine?

[alexis]

I have a page that lists a bunch of PDFs. I want to give people the choice whether they want to open it or save it to the disk. To do that I make the link through a php file using the header function (http://www.php.net/manual/en/function.header.php).

I do want these PDFs to be read by search engines like google.

What does google do when prompted with that dialog box? Does it even "see" it?

If it ignores it I want to make a if: if agent is a search engine, then don't put "content-disposition:attachement". (for the file name issue it's no problem since all my urls are made up by mod_rewrite)

[dcrombie]

I think you'll find that Content-Disposition is meaningless to search engines ;)