if(!isset($_SERVER["DOCUMENT_ROOT"]))
{$_SERVER["DOCUMENT_ROOT"]=substr($_SERVER['SCRIPT_FILENAME'] , 0 , -strlen($_SERVER['PHP_SELF'])+1 );
}

it simply works!
chris at vault5 dot com
30-Nov-2005 11:17
Since $_SERVER['DOCUMENT_ROOT'] is not always present, the following will provide it where $_SERVER dosen't.

<?php
function resolveDocumentRoot() {
    $current_script = dirname($_SERVER['SCRIPT_NAME']);
    $current_path   = dirname($_SERVER['SCRIPT_FILENAME']);
   
    /* work out how many folders we are away from document_root
       by working out how many folders deep we are from the url.
       this isn't fool proof */
    $adjust = explode("/", $current_script);
    $adjust = count($adjust)-1;
   
    /* move up the path with ../ */
    $traverse = str_repeat("../", $adjust);
    $adjusted_path = sprintf("%s/%s", $current_path, $traverse);

    /* real path expands the ../'s to the correct folder names */
    return realpath($adjusted_path);   
}