This approach has remained consistent through the years, and is based on: Each CMS user has control over a private virtual machine – a simulated copy of the underlying physical computer – in which CMS runs as a stand-alone operating system. An exceptionally strong user community, first established in the self-support days of CP/CMS but remaining active after the launch of VM, made substantial contributions to the operating system, and mitigated the difficulties of running IBM's "other operating system".ĬMS is an intrinsic part of the VM/CMS architecture, established with CP/CMS. This conflict is why CP/CMS was originally released as an unsupported system, and why VM often had limited development and support resources within IBM. VM was not one of IBM's "strategic" operating systems, which were primarily the OS and DOS families, and it suffered from IBM political infighting over time-sharing versus batch processing goals. See CMS under CP-40 for examples.īoth VM and CP/CMS had checkered histories at IBM. Many key user interface decisions familiar to today's users had already been made in 1965, as part of the CP-40 effort. Through all its distinct versions and releases, the CMS platform remained still quite recognizable as a close descendant of the original CMS version running under CP-40.
#Ibm t860 monitor series#
VM went through a series of versions, and is still in use today as z/VM. Unlike CP/CMS, VM/370 was supported by IBM. In 1972, IBM released its VM/370 operating system, a re-implementation of CP/CMS for the System/370, in an announcement that also added virtual memory hardware to the System/370 series. Despite this lack of support from IBM, CP/CMS achieved great success as a time-sharing platform by 1972, there were some 44 CP/CMS systems in use, including commercial sites that resold access to CP/CMS.
#Ibm t860 monitor code#
IBM provided CP/CMS "as is" – without any support, in source code form, as part of the IBM Type-III Library.