Boy, that was fun. Just wrote ean2isbn to convert the EAN bar codes to their proper ISBN. You'll need python installed to run it. It verifies that the EAN check digit is correct and generates the ISBN check digit for you.
It's kind of interesting, University of California lists two different books for the same ISBN number even though the check digits isn't correct, sounds like someone entered the data incorrectly:
hydrogen,ttyp6,/tmp/yaz-1.6,534$client/yaz-client tcp:128.48.141.7:210 Connecting...Ok. Sent initrequest. Connection accepted by target. ID : Z39.50 Name : CDL Z39.50 SERVER Version: 1.0 Z> base cat Z> find @attr 1=7 0937175935 Sent searchRequest. Received SearchResponse. Search was a success. Number of hits: 2, setno 1 records returned: 0 Z> show +2 Sent presentRequest (1+2). Records: 2 [Catalog]Record type: USmarc 001 5856206 003 CU-UC 005 20010124215609.3 008 890905s1989 caub r 00010 eng d 020 $z 0937175930 035 $9 5856206 040 $a SSL $c SSL $d CAS $d OCL $d CUS 100 10 $a Frey, Donnalyn 245 14 $a !%@:, a directory of electronic mail addressing and networks / $c Donn alyn Frey and Rick Adams. 250 $a 1st ed. 260 0 $a Sebastopol, CA : $b O'Reilly & Associates, $c c1989. 300 $a xv, 284 p. : $b maps ; $c 23 cm. 440 0 $a Nutshell handbook 500 $a At head of title on cover: UNIX Communications. 504 $a Includes bibliographical references and indexes. 546 $a English 650 0 $a Electronic mail systems $x Directories 700 10 $a Adams, Rick 740 01 $a Directory of electronic mail addressing and networks. 740 01 $a UNIX Communications. [Catalog]Record type: USmarc 001 7612099 003 CU-UC 005 20010124215609.6 008 930310s1992 caua 001 0 eng 010 $a 93124509 //r96 020 $a 0937175935 035 $9 7612099 040 $a DLC $c DLC $d DLC 050 00 $a QA76.76.O63 $b O73 1992 082 00 $a 005.7/13 $2 20 100 1 $a O'Reilly, Tim 245 10 $a Managing UUCP and Usenet / $c Tim O'Reilly and Grace Todino. 250 $a 10th ed. 260 $a Sebastopol, CA : $b O'Reilly and Associates, $c 1992. 300 $a xxiii, 342 p. : $b ill. ; $c 23 cm. 440 2 $a A Nutshell book 500 $a Includes index. 546 $a English 630 00 $a UUCP 630 00 $a UNIX (Computer file) 650 0 $a Usenet (Computer network) 700 10 $a Todino, Grace nextResultSetPosition = 0 Z>
Now to write/find an MARC parser to parse the data from the YAZ client.