Post commit script examples?

[Greg Alexander]

Hello,
    I am a very new Subversion user and am trying to get a post commit hook 
script working. My Subversion is running on linux. The script I want to add 
would add the needs-lock property to every file that didn't have a lock. Any 
pointers on this would be great. I have searched and not found any good, 
working, examples on how to do this.
     Thanks,
     Greg