The SVR5 kernel is based on the SCO SVR5 2.0 kernel with additions of SCO OpenServer 5 technology as appropriate.
The native ddi versions for SVR5 are ddi: 8, ddi: 8mp, sdi: 4, and mdi: 2. Drivers that use ddi: versions from ddi: 5 and sdi: 2 forward can be installed, although we recommend that drivers be written to conform to ddi: 7 and sdi: 3 or higher versions for portability to future releases. Note that support for ddi versions 1 through 4 and sdi version 1 have been dropped for SVR5. Additional versioned interfaces have been added to the system to support network adapter drivers and I2O drivers, among others. See ``DDI interface versioning'' for detailed information about supported interface versions.
The SVR5 versioning scheme is enhanced to support versioning of structure layouts and to enforce versioning for driver entry point routines that are documented in the D2 manual page sections.
Several major improvements in the fundamental kernel file and memory subsystems will drive new versions in the generic (meaning not subsystem-specific) device driver interfaces. This includes the following enhancements:
The SVR5 Hardware Developer's Kit also includes support for the following: