Hewlett-Packard Co and its Unix development partner Santa Cruz Operation Inc are supposed to publish 32-bit and 64-bit application programming interfaces for their next generation 3DA Unix operating system architecture this week. They’ve been out for review with OEMs and ISVs since last summer. HP and SCO will use the APIs as the basis of new versions of their Unix operating systems which are being designed specifically to run on the Merced processor, the first implementation of Intel Corp’s 64-bit IA-64 instruction set. Other vendors will port the design to different instruction sets. For example NEC, Siemens/Pyramid and Silicon Graphics are implementing 3DA on the Mips RISC. The three dimensions of HP/SCO’s 3DA Unix architecture are described as modular functionality, processor optimization and system optimization. The first release of the API specification includes definitions for Unix 95, 64-bit extensions (Aspen), Distributed Computing Environment, X11 X Windows, OSF Motif, Common Desktop Environment, Posix.1x, XPG 4.2, network, graphics, management and Internet services, plus APIs from HP and SCO’s existing Unixes. Future releases of the spec will address clustering and security, techniques which will be supplied by HP, SCO or their development partners. HP has already said it’ll incorporate the spec into the 11.0 release of its HP-UX Unix due mid-1997. SCO will support the spec in its Gemini merged UnixWare/OpenServer Unix release also due mid-1997.