Not complete, you must also have write permissions on the file. What if the directory is 777 but he file is 644 and owned by root or file is owned by you and is 444?

Nope on unix if you have write permission to the directory you can delete the file, even if it is owned by root and not even readable by you, on Solaris it comes up with a "override protection 600" prompt and then it is gone, tested on BSD and Linux as well.

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Until you've lost your reputation, you never realize what a burden it was or what freedom really is. -Margaret Mitchell