ction for membership in the list.
        If the check fails (including the possibility that the
        connection didn't use TCP/IP transport), the application
        responds by closing the connection.<p>

        <tt>FCGI_WEB_SERVER_ADDRS</tt>
        is expressed as a comma-separated list of IP
        addresses.  Each IP address is written as four decimal numbers
        in the range [0..255] separated by decimal points.  So one
        legal binding for this variable is
        <tt>FCGI_WEB_SERVER_A