Data General AOS

Data General wrote operating systems for its hardware: DOS and RDOS for the 16-bit Nova line; RDOS and AOS for the 16-bit Eclipse C, M and S lines; AOS/VS (1980) and later AOS/VS II (1988) and AOS/RT32 (1988) for the 32-bit Eclipse MV line; and a modified version of System V Unix called DG/UX for the 32-bit Eclipse MV and the 88K and x86 AViiON machines. The AOS software was far more advanced than competing PDP-11 operating systems, and 16-bit AOS applications ran natively under AOS/VS and AOS/VS II on the 32-bit Eclipse MV line, where Digital's VAX-VMS was entirely new. AOS/VS was the most commonly used DG software product, and included CLI (Command Line Interpreter) allowing for complex scripting, DUMP/LOAD, and other custom components.

The 16-bit version of CLI is famous for including a command taken directly from the Colossal Cave Adventure game. A user typing in the command "xyzzy" would get back a response from the CLI of "Nothing Happens".

When a 32-bit version of CLI became available under AOS/VS II, the same command instead reported "Twice As Much Happens"