NOS/VE

NOS/VE, short for Network Operating System / Virtual Environment, was a time-sharing operating system written by Control Data Corporation in the 1980s and is now discontinued. It was a virtual memory operating system that used the 64-bit virtual mode of the CDC Cyber 180 series of mainframe computers, and it replaced the earlier NOS and NOS/BE systems that CDC had offered in the 1970s. Users controlled it through a command shell called the System Command Language, or SCL. Commands had to declare their parameters, which allowed automatic usage summaries, passing arguments by name or by position, and type checking of values. Standard commands followed a verb, adjective, noun naming pattern and could be abbreviated, and subsystems such as FTP plugged into the shell and added their own commands.