If your apache server is running with the lowest possible permissions, you don't have much of a choice. All you can do is write your code, with the knowledge that anyone can read or write that directory. Check you user input, and only allow valid responses to work.

Another thing about this, is that other users on the server, may be able to get access to your directories. Suexec was designed to help thwart that problem.

<PS>Perlshop does a pretty good job of it, but there are places it needs improvement, be careful of cc numbers in 777 directories. I made an improved version of Perlshop, for my own use, you may find some ideas from it.Perlshop-Z</PS>