How to Mass rename files using PHP

I remember using PHP to add a file-extension to all files in a certain directory, but how do I use PHP to remove part of a filename for all files?

I have files in one directory like xx.avi.flv which should be xx.flv

Can anyone help?

 

A quick example written from your question

http://sourcecodedb.com/19927559808-Mass-renaming-files-in-a-folder.html

 

brilliant and brilliant idea for creating content for the site!

 

Actually doesn't work..I get this error:
Parse error: syntax error, unexpected T_DNUMBER on line 3...is there something missing?