I suspect that the public domain VM/370 is fair game. It was the basis for Amdahl's VM/470 which was used by the technicians during machine installations. They used it as an operating system to drive several diagnostics and exercise the virtualization hardware.
Jerry dePass, who was then the VM program manager for IBM, used to laugh about the package he received in the mail from Dewayne Hendricks of Amdahl. He took it to the legal department unopened. When the lawyer opened it, it was the VM/470 source code. One of the big differences between the two VMs was that VM/470 had no DMKRIO or DMKSYS. It sensed I/O devices and allowed its operator to define or delete devices during its first IPL. When finished defining devices, it would save the configuration for future IPLs. This was mid 1970s. Regards, Richard Schuh -----Original Message----- From: The IBM z/VM Operating System [mailto:[EMAIL PROTECTED] On Behalf Of George Haddad Sent: Monday, May 07, 2007 10:21 AM To: IBMVM@LISTSERV.UARK.EDU Subject: Re: z/VM usability Before I ever used VM a company where I worked had timeshare accounts at NCSS using VP/CSS. Except for the "personal disk" being P instead of A, it resembled CP/CMS quite a bit. I wonder if that ever got open-sourced? For that matter, are the "public domain" versions of VM/370 fair game for modification? Paul Raulerson wrote: > Has anyone written a third party OS that can easily replace CMS? I mean, CMS, despite being tightly integrated to all things VM, is in the final analysis, "just another Host OS" isn't it? Surely over 40 years someone has written something that can be used to replace it, perhaps something open source? > -Paul > >
