Vendor/phpspreadsheet/phpoffice/phpspreadsheet/src/PhpSpreadsheet/Reader/Xls/Escher.php
private function readDefault()
    {
        // offset 0; size: 2; recVer and recInstance
        $verInstance = Xls::getUInt2d($this->data, $this->pos);

        // offset: 2; size: 2: Record Type
        $fbt = Xls::getUInt2d($this->data, $this->pos + 2);

        // bit: 0-3; mask: 0x000F; recVer
        $recVer = (0x000F & $verInstance) >> 0;

        $length = Xls::getInt4d($this->data, $this->pos + 4);
        $recordData = substr($this->data, $this->pos + 8, $length);

        // move stream pointer to next record
        $this->pos += 8 + $length;
    }
private function readDefault()
    {
        // offset 0; size: 2; recVer and recInstance
        $verInstance = Xls::getUInt2d($this->data, $this->pos);

        // offset: 2; size: 2: Record Type
        $fbt = Xls::getUInt2d($this->data, $this->pos + 2);

        // bit: 0-3; mask: 0x000F; recVer
        $recVer = (0x000F & $verInstance) >> 0;

        $length = Xls::getInt4d($this->data, $this->pos + 4);
        $recordData = substr($this->data, $this->pos + 8, $length);

        // move stream pointer to next record
        $this->pos += 8 + $length;
    }
Read a generic record.