* <code>null</code> is returned.
     * 
     * @return URL to the DFS volume
     * @throws SmbException
     */
    public String getDfsPath () throws SmbException {
        try {
            String path = this.treeConnection.ensureDFSResolved(this.fileLocator).getDfsPath();
            if ( path != null && isDirectory() ) {
                path += '/';
            }
            return path;
        }

    private boolean isExists;
    private int shareAccess = FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE;
    private SmbComBlankResponse blank_resp = null;
    private DfsReferral dfsReferral = null;  // For getDfsPath() and getServerWithDfs()

    protected static Dfs dfs;

    NtlmPasswordAuthentication auth; // Cannot be null
    SmbTree tree = null;             // Initially null