Extending a stand-alone personal computer to integrate multiple operating systems concurrently

This paper presents a virtual I/O approach to extend an existing personal computer to provide a multiple operating environment. Multiple operating systems can be executed simultaneously, each using a separate window as its console display. A user can swiftly switch his work among different operating systems by activating corresponding windows. Furthermore, these operating systems can be integrated so that the programs under their control can cooperate with each other in a transparent manner. The cooperation is established by using a shared file system and a guest layer mechanism. Current portable operating systems can be easily ported and integrated. A personal computer has been extended to integrate up to four different operating systems. This experimental system is presented to show the advantages of integrating multiple operating systems in a stand-alone machine and serves as the base for further exploration.