yaz_marc_set_read_format(mt, input_format);
yaz_marc_set_write_format(mt, output_format);
yaz_marc_write_using_libxml2(mt, write_using_libxml2);
yaz_marc_set_read_format(mt, input_format);
yaz_marc_set_write_format(mt, output_format);
yaz_marc_write_using_libxml2(mt, write_using_libxml2);