I wouldn't.  One of the benefits of marcxml is that you are not constrained by marcs record length issues.  Deciding to calculate that value would add an arbitrary length limitation to the format (in my opinion).

Tr

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Terry Reese, Associate Professor
Gray Family Chair for
Innovative Library Services
121 Valley Library
Corvallis, OR 97331
541.737.6384
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________________________________
From: Sullivan, Mark V
Sent: 6/29/2012 6:52 AM
To: [log in to unmask]
Subject: [CODE4LIB] Leader in MarcXML Files ( Record Length )

All,



I received a question regarding a software library I have created and released as open source.  The record length in the leader ( positions 0-4 ) was not being calculated correctly when writing as MarcXML.  However, this raises a more philosophical and larger question.  What is the point of the first five digits of the leader, outside of a ISO2709 / MARC21 encoded record?   Should I calculate the record length AS IF it would be encoded in ISO2709? This would be computationally non-trivial and would likely double the time necessary for my software to write a MarcXML file. Should I just make the first five digits of the leader '00000', since it means nothing in the context of a MarcXML file?



Has anyone else pondered this question or have any input on how current systems work?



Keep in mind I could be writing a MarcXML record for a record created or modified in memory, so just using a pre-existing record length is not an option.



Many thanks for your consideration.


Mark V Sullivan
Digital Development and Web Coordinator
Technology and Support Services
University of Florida Libraries
352-273-2907 (office)
352-682-9692 (mobile)
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