When 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.
This function sets sorting criteria and enables Z39.50 Sort. Call this function before yaz_search(). Using this function alone doesn't have any effect. When 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