[Koha-devel] MARC::Record, record length and leader

[Colin Campbell]

On Wed, Apr 11, 2012 at 11:34:07PM +1200, Robin Sheat wrote:
> Op 11-04-12 23:12, Ian Walls schreef:
> 
> It's not really for that, it's to allow seeking through records on tape
> to be efficient (at least, the way it's designed suggests that to me.)
I'm old enough to confirm thats the purpose although even back in those
days you kept encountering incorrect values it was always easier to
kludge the reader software than drum the concept of standards into
record suppliers heads,
> 
> This would be OK for a single record. My concern is if we ever end up
> with a block of USMARC records glommed together, could we separate them
> out without a correct length header? Is there an "end of record" flag?
Each record ends with a hex 1D Record Terminator character.
Best MARC handling library I've used in the past encoded the leader
internally onto its own fields, holding the record length as an integer,
then converting that on output. Apart from a couple of characters
flagging the bib level and type the bulk of the leader is noise to most
users and should be the softwares responsibilty to maintain correctly.

As long as you can generate valid MARC on output and feed it in how you
hold the record internally is flexible.

Colin

-- 
Colin Campbell
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