Real-Time Multiprogramming Operating System (RTMOS) was a 24-bit process control operating system developed in the 1960s by General Electric that supported both real-time computing and multiprogramming. Programming was done in assembly language or Process FORTRAN. The two languages could be used in the same program, allowing programmers to alternate between the two as desired.
Multiprogramming operating systems are now considered obsolete, having been replaced by multitasking.
References
GE-PAC 4020 Programming Manual. General Electric. 1967. p. 5. Retrieved 2013-09-27. https://archive.org/details/bitsavers_gePAC4000P0PgmgManOct67_6687740/mode/1up ↩
Spang, H. A. III (January 1972). "The structure and comparison of three real-time operating systems for process control". Automatica. 8 (1): 49–64. doi:10.1016/0005-1098(72)90009-X. Retrieved 23 August 2013. http://dl.acm.org/citation.cfm?id=2244947 ↩
Spang, H. A. III (1974). Measurement and Improvement of Memory Allocation in a Process Computer. 4th IFAC/IFIP International Conference on Digital Computer Applications to Process Control. Vol. 93. pp. 236–247. doi:10.1007/978-3-642-65796-2_20. /wiki/Doi_(identifier) ↩
GE-PAC 4020 Programming Manual. General Electric. 1967. p. 5. Retrieved 2013-09-27. https://archive.org/details/bitsavers_gePAC4000P0PgmgManOct67_6687740/mode/1up ↩