This function sets sorting criteria and enables Z39.50 Sort. Use this function together with yaz_search() or yaz_present(). Using this function alone doesn't have any effect. If used in conjunction with yaz_search() a Z39.50 Sort will be sent after a search response has been received and before any records are retrieved with Z39.50 Present. The criteria takes the form
field1 flags1 field2 flags2 ...
where field1 specifies primary attributes for sort, field2 seconds, etc.. The field specifies either numerical attribute combinations consisting of type=value pairs separated by comma (e.g. 1=4,2=1) ; or the field may specify a plain string criteria (e.g. title. The flags is a sequnce of the following characters which may not be separated by any white space.
Sort Flags
Sort ascending
Sort descending
Case insensitive sorting
Case sensitive sorting