Uniform Driver Interface
The UDI Specifications represent the official definition of the UDI interface. These specifications contain the only "normative" documentation (that is, the official definition of the interfaces). All other documents are "informative": they provide useful information and background to help in understanding how to use and implement UDI environments and drivers.
The UDI Specifications are organized into multiple books, as described in detail in the "Document Organization" chapter of the UDI Core Specification. The UDI Core Specification contains the definitions for UDI services and facilities required in all UDI environment implementations. The other specification books represent independent, optional services which may be common but are not required in all implementations.
NOTE: These are searchable, hyperlinked PDF documents, but if you plan to print them, some of them are very large (in particular, the two Core specs and Physical I/O), and we recommend professional printing and binding at a copy center.
The following document is not part of the official specifications, but is a useful guide for driver writers:
The following document is not part of the official specifications, but is a useful guide for OS implementers:
Draft design and specification for a UDI Driver Test Suite, by SCO (from stage.sco.com)
Click here for information on related specification efforts. (Some of this may be out of date.)