The solo operating system: Processes, monitors, and classes
Per Brinch Hansen · Software Practice and Experience · 1976
Abstract This paper describes the implementation of the Solo operating system written in Concurrent Pascal.* It explains the overall structure and details of the system in which concurrent processes communicate by means of a hierarchy of monitors and classes. The concurrent program is a sequence of nearly independent components of less than one page of text each. The system has been operating since May 1975.