Most existing programs can be converted simply by relinking. Programs with larger code or data requirements can be generated in the same way. The Prospero DOS Extender kit includes a new linker capable of generating protected mode programs for each of the environments. For each extender, either complete new libraries or extra modules to be used with the standard libraries are supplied. Model batch files are also given showing how to link programs.
Full documentation is provided, including advice on programming in protected mode.
DPMI DPMI is not itself an extender, but rather a definition of an interface. Graphics support is provided, including direct screen writes. A special version of Probe is also supplied to allow debugging of programs in this environment. A number of DPMI extender implementations are available. The most notable is Windows 3 running on an 80386, not using the windows environment, but the DOS command shell provided within Windows.