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VB to FB dataset conversion and calculation of byte count

 
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gchoud

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Joined: 01 Mar 2007
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Location: sydney

PostPosted: Tue Mar 06, 2007 6:35 am    Post subject: VB to FB dataset conversion and calculation of byte count
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Can any one advise the method to convert VB format datset to FB format datset through JCL.I have searched and could not get proper answer.

Also is it possible to calculate the exact byte count for VB file manually.Looking to match that number of bytes send through xcom to different system so as to ensure that xcom is proper and no bytes were lost.

Thanks in advance.
Gautam
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dick scherrer

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PostPosted: Tue Mar 06, 2007 9:10 am    Post subject:
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Hello,

Does the VB file actually have records of varying lengths? Are there different recvord formats ikn the variable file? Is it possibly a delimited file? It will help if you post the definition of the VB file and the FB file.

Please explain more about the byte count to ensure complete transmission. Where (which platform) does the transmission originate and where is the data received?

Are you familiar with how a variable length block is physically constructed? The first bytes are a block descriptor that contains the length of that block. Next is a record descriptor that contains the length of the first record. If you hex dump the first couple of blocks of the variable file, you will see the block descriptor & record descriptor fields. For a file byte count, you only need the block descriptors. Total them and you will have the length of the variable file.

Transmissions sometimes fail, but i've not seen any individual bytes lost for a verylong time.
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gchoud

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PostPosted: Tue Mar 06, 2007 10:15 am    Post subject: Re: VB to FB dataset conversion and calculation of byte coun
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Thanks for the above information.I was some what aware of how the files are construsted.( 4 byte + the rec)

Please find below some more information ..

How this VB datset was generated ?

Cobol program creates the FB file on Mainframe and this fixed block file are stored as back up in mainframe as varible block file.The original file did not had any delimiter nor was any added during back up process.


Files are transmitted from mainframe to Stratus platform through XCom from mainframe.


Sometimes for recovery purpose the back up file created in VB format needs to be changed to FB format and need to be xcomed.



On the byte count:
I just want to know how can we count the actual byte for a VB dataset.( that is the total size of file in bytes)

How to take hex dump?.When I browse the file and give HEX after going inside file ..it does not give the Hex for file descriptor.It has Hex for the rest of the data.

Many thanks..looking forward to response.
Thanks
Gautam
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dick scherrer

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PostPosted: Tue Mar 06, 2007 8:25 pm    Post subject:
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Hello,

I'm unclear on what this means:
Quote:
Cobol program creates the FB file on Mainframe and this fixed block file are stored as back up in mainframe as varible block file.


If the data was created FB, how is it stored as VB?

Check with someone (the system support group) at your location and ask if you have a program called DITTO available. With that utility you can easily "dump" blocks in hex. If they say they don't have DITTO, ask them for jcl to dump physical blocks. You only need the first few blocks to see the descriptor words. You might want to dump a few blocks from both the FB and VB files that were created from the same data. Then you will be able to see how the different files are constructed.
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gchoud

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Location: sydney

PostPosted: Wed Mar 07, 2007 10:42 am    Post subject: Re: VB to FB dataset conversion and calculation of byte coun
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Thanks for the above suggestion will check.

Original file is created in FB.No issues.Later this file is deleted and stored as FB format.The original file is copied to VB file through IDCAM/some other utility before the original file in FB is deleted.


Regards
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