PhpSigep\Pdf\VariableStream::stream_seek PHP Метод

    function stream_seek($offset, $whence)
    {
        switch ($whence) {
            case SEEK_SET:
                if ($offset < strlen($GLOBALS[$this->varname]) && $offset >= 0) {
                    $this->position = $offset;
                    return true;
                } else {
                    return false;
                }
                break;
            case SEEK_CUR:
                if ($offset >= 0) {
                    $this->position += $offset;
                    return true;
                } else {
                    return false;
                }
                break;
            case SEEK_END:
                if (strlen($GLOBALS[$this->varname]) + $offset >= 0) {
                    $this->position = strlen($GLOBALS[$this->varname]) + $offset;
                    return true;
                } else {
                    return false;
                }
                break;
            default:
                return false;
        }
    }