Multiple Console Time Sharing System

{{Infobox OS

| name = GM Multiple Console Time Sharing System (MCTS)

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| developer = General Motors Research Laboratories

| family = Multics

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| released = 1970s

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| language = English

| kernel type = N/A

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| ui = Command-line interface

| license = none

| working state = Historic

| supported platforms = Control Data Corporation STAR-100

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The Multiple Console Time Sharing System (MCTS) was an operating system developed by General Motors Research Laboratories in the 1970s for the Control Data Corporation STAR-100 supercomputer. MCTS was built to support GM's computer-aided design (CAD) applications.{{cite journal |last1=Elshoff |first1=James L. |last2=Ward |first2=Mitchel R. |title=The MCTS operating system |journal=ACM SIGOPS Operating Systems Review |volume=10 |issue=1 |date=January 1976 |pages=18–38 |doi=10.1145/775314.775317 |doi-access=free}}

MCTS was designed starting in 1968. It was written in a high-level systems programming language "Malus", a dialect of PL/I. A superset of Malus called Apple became the primary application language.{{cite journal |last1=Brown |first1=R.R |last2=Elshoff |first2=J.L. |last3=Ward |first3=M.R. |title=The GM Multiple Console Time Sharing System |journal=ACM SIGOPS Operating Systems Review |date=1 Oct 1975 |volume=9 |issue=4 |pages=7–17 |doi=10.1145/775310.775311 |url=https://dl.acm.org/doi/10.1145/775310.775311|access-date=July 1, 2024}}

MCTS was based on Multics.Krull, pg. 54 All access to data was through the virtual memory system. Only the system paging support module was concerned about the physical location of the data.