RE: CPF5175 - Incorrect Record for Output Operation to Save File

Finding the source of data corruption over comms lines is really
difficult since its usually so intermittent its hard to track. Line
noise, interference and overheated hardware are two causes. Since you'll
never be able to totally eliminate the possibility of comms errors you
should prepare your comms application to deal with them. What I do is to
include a CRC with each record I send and verify that on the remote end.
You don't need to acknowledge each record as having been received ok
(that would hurt throughput) but if this is an SNA link you could
CONFIRM/RSPCONFIRM to confirm blocks of records and resend a block if
needed. I have a little piece of code that generates 16 and 32 bit CRCs
if you decide to go this route. 

> -----Original Message-----
> From: Reger, Bill [SMTP:breger@levitz.com]
> Sent: Friday, August 13, 1999 4:36 AM
> To:   'MIDRANGE-L@midrange.com'
> Subject:      RE: CPF5175 - Incorrect Record for Output Operation to
> Save File
> 
> Thanks for the comments about the ICF major/minor codes and about the
> save
> file checksum.
> 
> The major/minor codes are fine!  In fact, this problem usually occurs
> on the
> last record being received via ICF and the "sending" system is
> assuming
> everything is fine and merrily continuing on to do its thing (usually
> to
> "grandfather" the save file).
> 
> The checksum is what is probably causing the receiving program to
> recognize
> the problem with the save file.  What I'm looking for is possible
> "causes"
> of this situation, so that hopefully I can help eliminate them.
> Thanks,
> Bill
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