Virtual Window Systems: A New Approach to Supporting Concurrent Heterogeneous Windowing Systems
Rita Pascale, Jeremy Epstein · 1992
A "virtual window systeml ' (VIWS) is a simple model of a window system which can be used to host other more sophisticated window systems. The VWS allows the window systems to share the.phys_ical 9ppl.y in a controlled fashion. A VWS is analogous to the virtual machine monitor (vMM) [MadnickT4] concept in operating systems, where a single ghysical compr¡ter-can run multiple operating systems, each in itõ o-*n protection domain.Unlike the VMM concept, the window iysiems supported by the VWS need close cooperation to perform'tasks, such as cut and paste between wináows of different window systems. This paper describes the VWS concept, discusses an architecture for a VWS, describes limitations of the \\l[VS concept, discusies some lessons learned from the design and implementation of our prototype, and describes the use of WVSs for various application domains. Introduction MacOS and X; X-under-NeXTstep from pencom Users want to run more than one window svs _ which combines NeXT and X; and Domain from tem (WS) simultaneously on a single platiãi.. ínr f¡to,llo_which combines Apollols native WS and X.