How to get the full path to php interpreter / binary without shell access
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How can I get the full path to php interpreter from a php script (no command line access).

What I need to do is:

    $foo = "/usr/bin/php";
    echo $foo;

But I need to get the path first so I can assign it to foo. 

If you have a solution that works on both Windows and nix even better but if not, nix would be fine.

Before you ask,

1. Asking the host is out of the question
2. No shell access