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What does RDW mean

 
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picus_mf
Warnings : 1

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Joined: 09 Jun 2006
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PostPosted: Wed Jul 09, 2008 5:12 pm    Post subject: What does RDW mean
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Hello,

Can any one give explanation why extra 4 bytes for variable record length and what does '4 byte BDW/RDWs' mean?
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enrico-sorichetti

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PostPosted: Wed Jul 09, 2008 5:18 pm    Post subject: Reply to: What does RDW mean
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they are ...
BDW Block Descriptior Word
RDW Record Description Word
the term sounds a bit funny because only the first halford is used..
both BDW and RDW are usually referred to as having the format "LLbb"
2 bytes for the length and two blank bytes
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Robert Sample

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PostPosted: Wed Jul 09, 2008 5:21 pm    Post subject:
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BDW -- Block Descriptor Word
RDW -- Record Descriptor Word

The length of a variable length record needs to be specified somehow. On the mainframe the RDW holds the length of the variable length record in the first 2 bytes; the last 2 bytes are reserved. The BDW holds the length of the block in the first 2 bytes and again the last 2 bytes are reserved.
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ofer71

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PostPosted: Wed Jul 09, 2008 5:23 pm    Post subject:
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It's all in the fine manual.

O.
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