We often receive files on unlabelled tapes from our clients with no
specs -- the tapes, not the clients -- and they are not in the record
format we have asked for. This gives our programmers fits when they have
to try to load the data from the tape to a file on the system and be
reasonably sure they got everything right.

We can find out the block size by doing a tape dump on one of our
AS/400's (btw, any easy way to find this out on an HP3000?) but have no
way of knowing, for example, if a file with a block size of 8160 was
created with:

REC=-8160,1,F,ASCII  -or-
REC=-816,10,F,ASCII  -or-
REC=-680,12,F,ASCII  -or-
REC=-510,16,F,ASCII  -or-
REC=-340,24,F,ASCII  -or- ... (you get the idea)

ad nauseum, without actually dumping the tape a few times and examining
the output.

Does anyone have a program or utility that will read a block (or two or
three) from a tape and return a 'guesstimate', based on similar and/or
repeating data or data types, of what the actual record length and
blocking factor should be? I know, I'm only asking for the moon.

BTW, we get tapes in EBCDIC format as well and have the same problem. We
do a *lot* of tape processing, so any and all suggestions, off-list or
on, are welcome.

TIA,
Patrick
--
Patrick Santucci
Technical Services Systems Programmer
KVI, a division of Seabury & Smith
Visit our site! http://www.kvi-ins.com
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