tFPDF::_readstream PHP Method

    function _readstream($f, $n)
    {
        // Read n bytes from stream
        $res = '';
        while ($n > 0 && !feof($f)) {
            $s = fread($f, $n);
            if ($s === false) {
                $this->Error('Error while reading stream');
            }
            $n -= strlen($s);
            $res .= $s;
        }
        if ($n > 0) {
            $this->Error('Unexpected end of stream');
        }
        return $res;
    }