21 Sep
2023
21 Sep
'23
3:58 a.m.
-----Original Message-----
From: Dennis Boone via cctalk <cctalk(a)classiccmp.org>
Sent: Thursday, September 21, 2023 4:33 AM
To: General Discussion: On-Topic and Off-Topic Posts
<cctalk(a)classiccmp.org>
Cc: Dennis Boone <drb(a)msu.edu>
Subject: [cctalk] Re: IBM VM "CMS" tape format
> Ive got a tape here from what I believe to be a VM system. The >
structure is
unknown to me, although I can possibly take a stab at
> it. Lots of data
between tapemarks that seems to consist of a number > of records that
start
out something like this (translated from >
EBCIDC):
I think this might be the older VMFPLC (not VMFPLC2) format, used by IBM
for
software distribution and other things. The format
seems fairly
simple: Five character block header (x'02' 'CMS' 'N' or
'0'), 800 bytes of
contents.
First block is the FST for the file.
Never seen a VMFPLC format tape, only VMFPLC2 or CMS TAPE command format.
The main difference between CMSTAPE and VMFPLC2 is one has the FST at the
start, the other at the end.
I tweaked some utils from old to read and write these in AW format...
https://1drv.ms/f/s!Ag4BJfE5B3onhK8KXjiJ7iUXUgRs8A?e=qS99zs
which may help..
https://www.garlic.com/~lynn/2003b.html#42
Old VMFPLC may be just CMS TAPE DUMP under the covers.
De
Dave