What's the safest method to access a php file thats outside the root directory?
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I've tried to search this elsewhere on stackoverflow and elsewhere on the net.

Can't seem to get a solid lock on an answer that suggests it's the safest way.

I know that the securest method is, where possible, to not include any php files in the root directory where it can be helped.

So, what I am trying to find out is, if I want to include a php file stored OUTSIDE the root directory, say, in another directory, what is the safest way for me to do that?