Compatibility with Windows 16-Bit APIs

Windows Version 3.0 and 3.1 applications will be able to run in Windows Enhanced-mode and Windows NT-mode systems that support the Windows 32 API. To be compatible with versions 3.0 and 3.1, all Windows 16 applications will run as one process in one address space. They will be nonpreemptive with respect to one another but preemptive with respect to the rest of the system, which mirrors their behavior under Windows Version 3.0 Enhanced-mode. Windows 16 applications run against the Windows 32-Bit APIs without a “layer” and without any state mapping or message reordering like that necessary to run them on OS/2 version 2.0.

Windows executables will also run on RISC-based Windows NT machines (see Figure 5). Excellent performance is expected on this platform because although some code will be run against 80286 emulator technology, all Windows calls will be mapped directly to the Windows NT software.