Horde_Mime_Part::_transferEncode PHP Method

    protected function _transferEncode($fp, $encoding)
    {
        $this->_temp['transferEncodeClose'] = true;
        switch ($encoding) {
            case 'base64':
                /* Base64 Encoding: See RFC 2045, section 6.8 */
                return $this->_writeStream($fp, array('filter' => array('convert.base64-encode' => array('line-break-chars' => $this->getEOL(), 'line-length' => 76))));
            case 'quoted-printable':
                // PHP Bug 65776 - Must normalize the EOL characters.
                stream_filter_register('horde_eol', 'Horde_Stream_Filter_Eol');
                $stream = new Horde_Stream_Existing(array('stream' => $fp));
                $stream->stream = $this->_writeStream($stream->stream, array('filter' => array('horde_eol' => array('eol' => $stream->getEOL()))));
                /* Quoted-Printable Encoding: See RFC 2045, section 6.7 */
                return $this->_writeStream($fp, array('filter' => array('convert.quoted-printable-encode' => array_filter(array('line-break-chars' => $stream->getEOL(), 'line-length' => 76)))));
            default:
                $this->_temp['transferEncodeClose'] = false;
                return $fp;
        }
    }