DNIX

DNIX was a Unix-like real-time operating system from the Swedish company Dataindustrier AB (DIAB). A version called ABCenix was also developed for the ABC1600 computer from Luxor. (Daisy Systems also had something called Daisy DNIX on some of their CAD workstations. It was unrelated to DIAB's product.)

Read more about DNIX:  History, Asynchronous Events, Handlers, ISC's Extensions