[comp.misc] HELP wanted with 9-T tape format

jrt@aeg.dsto.oz.au (J.R.Terry-AEG) (12/01/90)

I would greatly appreciate it if anyone can help with information
regarding IBM CMS Tape Dump format.

What I have so far is:

1. Tape file comprises data blocks (max length 4101 bytes) interspersed
with some sort of information block (presumably 1 for each file dumped
on the tape) of exactly 87 bytes.

2. Data blocks have ^BCMSF in EBCDIC (hex 02 C3 D4 E2 C6) in the first 
5 bytes followed by up to 4096 bytes of data organised as 80 column card 
images. The data bytes are also EBCDIC encoded.

3. Information blocks have ^BCMSN in EBCDIC (hex 02 C3 D4 E2 D5) in the
first 5 bytes then 82 bytes of what I presume to be directory type 
information (file name, size, date, etc.)

4. I would like to know how the data in these ^CMSN blocks is
interpreted so I can reconstruct the files that have been dumped.

5. No. I don't have an IBM mainframe with the VM operating system on it,
which I am told is what would have produced the tapes in the first
place.

6. If in addition, anyone knows of a utility for SUN or VAX platform
that will process this tape format, I would also be interested.

Many thanks to anyone who responds by E-Mail preferably or to this group
if appropriate.

JRT

--
John R Terry					    jrt@aeg.dsto.oz.au
Head, Avionic Computer Systems			    Ph:	+61 8 259 6982
Aeronautical Research Laboratory, DSTO Salisbury    Fax:+61 8 259 5507