MINIMOP

MINIMOP was an operating system which ran on the International Computers Limited (ICL) 1900 series of computers. MINIMOP provided an on-line, time-sharing environment (Multiple Online Programming, or MOP in ICL terminology), and typically ran alongside George 2 running batch jobs.^[1] MINIMOP was named to reflect its role as an alternative to the MOP facilities of George 3, which required a more powerful machine.^[2]

MINIMOP would run on any 1900 series processor apart from the low-end 1901 and 1902 and required only 16K words of memory and two 4 or 8 million character magnetic disks.

Each user was provided with a fixed size file to hold his data, which was subdivided into a number of variable sized subfiles. The command language could be extended with simple macros.

^ Cite error: The named reference dransfield-2012 was invoked but never defined (see the help page).
^ McLain, T.G.; Trice, A.R. (1970). "The MINIMOP multi-access operating system". The Computer Journal. 13 (3): 237–242. doi:10.1093/comjnl/13.3.237.

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[2] McLain, T.G.; Trice, A.R. (1970). "The MINIMOP multi-access operating system". The Computer Journal. 13 (3): 237–242. doi:10.1093/comjnl/13.3.237.

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