Background:
Once a month we receive an unlabeled 9-track tape 1600-bpi from a
vendor. This tape contains 25 different files of different record
lengths and block sizes.
Normally all the files fit onto 1 tape but occasionally it may span
onto 2. When the complete set of files is generated, the
information currently spans 8 tapes. A full dump of 1 of the files
uses 5 tapes.
Problem:
We have a script that uses 'dd' to read the tapes and update our
databases. This worked fine on our Ultrix systems. If a file
spanned a tape, 'dd' was smart enough to know that another tape
needed to be mounted to obtain more of the file.
With the migration to DU 3.2C, it seems that the 'dd' command has
changed. It appears that you need to know before starting the 'dd'
command how many tapes the file is contained on and specify the
"files=number" option so all of the files will be concatenated into
just 1 file. According to the 'dd' man page:
The dd command does not support floppy disk multi-volumes, but
it does support tape multi-volumes. This means that when ENOSPC
is returned while reading or writing a tape, dd will prompt the
user for a new tape. In order to make use of tape
multi-volumes, the files option must be used.
Does anybody have any idea how I can continue to have this function
automated without knowing know which file (if any) may span
multiple tapes? This script is run by a computer operator who has
only the ability select when to run pre-defined scripts and to
mount tapes.
The vendor can provide the data on 9-track tape, a 3480 cartridge,
and CD. In the future I might be able to start receiving the data
on CD (which would solve the problem) but currently 2 of the
computers running Ultrix which need to process the data do not have
CD drives. These computers are scheduled to be replaced over the
next few months so the solution I am seeking will be temporary.
Thanks in advance.
Karl E. Liliestedt karl_at_msdc.com
Medical Systems Development Corporation
Atlanta, Georgia
Received on Fri Aug 16 1996 - 18:40:19 NZST