IBM CMS dumpfile idiocy

Paul Koning paulkoning at
Wed Dec 16 09:57:40 CST 2015

> On Dec 15, 2015, at 10:10 PM, Chuck Guzis <cclist at> wrote:
> On 12/15/2015 01:48 PM, Dave Wade wrote:
>> What I meant was are they still on 9-track, or some kind of
>> tape-in-a-file disk? IBM tapes are usually written to AWS format
>> files not the formats (.TAP ?) used by SIMH... Some source to extract
>> some versions of these from AWS files (and windows executables) are
>> in this ZIP file:-
> Came right off a 1600 cpi tape, identified as a CMS dumpfile.
> What really strikes me as odd, is that ANSI/IBM tape labels were pretty much the standard rule of thumb then; why the heck did IBM invent something new and obscure?

IBM standard labels are older than ANSI.  Then again, IBM (in OS/360 at least) had something they called "ANSI label" that were not actually ANSI at all.  They used "8 bit ASCII" which was a bizarre code created from standard 7 bit ASCII by moving one or two of the bits (bit 6 to bit 7?  I don't remember).


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