[FX.php List] Find out if file available

[Glenn Singleton]

I am looking for the quickest leanest code to find out if a file is  
available for use.

That is I want to hit a web site with the least web-server intensive  
query possible to see if myfile.fp7 is available for queries with the  
username/password I supply.

There are lots of ways I can do this, but wondering what is the most  
efficient.

Please post sample code.

Regards
Glenn Singleton
glenn at cornerstoneict.com.au
glenn at thesingletons.id.au
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