Early 360 machines (Was: Front panel switches - what did they do?)

Paul Koning paulkoning at comcast.net
Thu May 26 08:51:30 CDT 2016

> On May 25, 2016, at 10:58 PM, Chuck Guzis <cclist at sydex.com> wrote:
> On 05/25/2016 07:22 PM, Paul Berger wrote:
>> Speaking of dumps I remember an engineer friend telling me that at
>> the university that he went to they had a CDC Cyber system and they 
>> discovered that you could initiate a dump from any workstation, and
>> the system would dump out to the printer and while it was dumping the
>> whole system came to a halt.... guess what the students where fond
>> of doing......  It would seem to me that something like that should
>> have been more restricted.
> At least in SCOPE and KRONOS, DMP was the command to dump memory--but if
> initiated from a user's control point, it would dump only the user's FL,
> not the whole system.  So the story seems to be a bit apocryphal to me.
>  Most university systems charged not only by the CPU second, but also
> by the number of lines printed and the number of cards punched.

Apart from that, it's not credible for another reason.  CDC Cyber operating systems always spooled printer output to disk (unlike OS/360 which did it in some variants but not others -- notably not OS/360 PCP which I used since our 360/44 wasn't big enough to do better).  So a call to DMP would run only long enough do perform the formatting of whatever memory was being dumped, writing the resulting text to the disk file named "OUTPUT" for the invoking process ("control point").


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