IBM CMS dumpfile idiocy

[Dave Wade]

> -----Original Message-----
> From: cctalk [mailto:cctalk-bounces at classiccmp.org] On Behalf Of Chuck
> Guzis
> Sent: 16 December 2015 22:14
> To: jwsmail at jwsss.com; General Discussion: On-Topic and Off-Topic Posts
> <cctalk at classiccmp.org>
> Subject: Re: IBM CMS dumpfile idiocy
> 
> On 12/16/2015 01:19 PM, jwsmobile wrote:
> > If it's an 80 byte record, the PSW is further into the block.  the
> > first 80 positions from the Green card should be a clue.
> 
> No, the first record is 4101 bytes long.  Interestingly, all blocks on
this tape
> are an odd number of bytes in length.
> 
> --Chuck

There is a 0x02 character, followed by "CMS" in EBCDIC then a record type
"V", "F" or "N" for the file status table.
>From the "cmstape.c" I sent you the link too....

/*
 * Format of a CMS TAPE DUMP tape entry for each file:
 *
 * 1) One or more blocks like this:
 *      +--+-+-+-+-+-+-+-----/ /-+-+-+-----
 *      |02|C M S V| l | data... | l | data...
 *      +--+-+-+-+-+-+-+-----/ /-+-+-+-----
 *       <-----------4101 bytes max---------->
 *
 *    or this (for fixed records (lrecl in the FST)):
 *      +--+-+-+-+-+-----/ /-+-+-+-----
 *      |02|C M S F| data... | l | data...
 *      +--+-+-+-+-+-----/ /-+-+-+-----
 *       <-----------4101 bytes max---------->
 *

 * 2) Followed by an ending FST + filename
 *      +--+-+-+-+-+------------+
 *      |02|C M S N|  FST data  |
 *      +--+-+-+-+-+------------+
 *       <-------87 bytes------>

Dave