private function findOffset()
    {
        $this->seek(0);

        $offset = 0;

        while (!$this->isEndOfFile()) {
            if (strtolower($this->read(1)) === self::$sequence[$offset]) {
                $offset++;
            } else {
                $offset = 0;
            }

            if (!isset(self::$sequence[$offset + 1])) {
                break;
            }
        }

        $this->seek(1, SEEK_CUR);

        if ($offset === (count(self::$sequence) - 1)) {
            $position = $this->getPosition();

            if ("\r\n" === $this->read(2)) {
                return $position + 2;
            }

            return $position;
        }

        return null;
    }
private function findOffset()
    {
        $this->seek(0);

        $offset = 0;

        while (!$this->isEndOfFile()) {
            if (strtolower($this->read(1)) === self::$sequence[$offset]) {
                $offset++;
            } else {
                $offset = 0;
            }

            if (!isset(self::$sequence[$offset + 1])) {
                break;
            }
        }

        $this->seek(1, SEEK_CUR);

        if ($offset === (count(self::$sequence) - 1)) {
            $position = $this->getPosition();

            if ("\r\n" === $this->read(2)) {
                return $position + 2;
            }

            return $position;
        }

        return null;
    }
private function findOffset ( ) { $ this -> seek ( 0 ) ; $ offset = 0 ; while ( ! $ this -> isEndOfFile ( ) ) { if ( strtolower ( $ this -> read ( 1 ) ) === self :: $ sequence [ $ offset ] ) { $ offset ++ ; } else { $ offset = 0 ; } if ( ! isset ( self :: $ sequence [ $ offset + 1 ] ) ) { break ; } } $ this -> seek ( 1 , SEEK_CUR ) ; if ( $ offset === ( count ( self :: $ sequence ) - 1 ) ) { $ position = $ this -> getPosition ( ) ; if ( "\r\n" === $ this -> read ( 2 ) ) { return $ position + 2 ; } return $ position ; } return null ; }
Finds the archive offset of an archive.

@return integer If the archive offset is found, it is returned. If a
archive offset is not found, `null` is returned.
Finds the archive offset of an archive .