List all 404s with target url on site?

[delphi123]

Hi folks,

 

need some brains around this - am needing to produce a script which will make a list of any visit to my site that finds a deadlink.

 

Was thinking I could use the .htaccess to display a custom 404 message which adds a line to a database - but can anyone tell me how to get the url of the page they were trying to visit? (or if there's a smarter way of doing this let me know! Haven't got access to the server logs unfortunately!)