In a series of releases, IBM have announced that their in-house version of Unix, AIX, will be released for ES/9000 and ESA/390 processors.
AIX/ESA will run native on ES/9000 and ESA/390 mainframes in a logical partition, or as a guest operating system under ESA. Amdahl have supplied a Unix implementation for their mainframes for a number of years.
AIX is based on the Open Software Foundation's OSF/1, as is also the Open Desktop implementation to be developed by the ACE consortium. OSF/1 supports the POSIX standard from the IEEE, a standard for an application programming interface. Programs written according to the POSIX standard will run on most Unix compatible operating systems, as well as a number of others. IBM has stated that they will support POSIX in their MVS and OS/400 operating systems. The industry standard X Window System will also be supported in AIX/ESA.
IBM have said that AIX/ESA "provides and IBM solutions where "mainframe UNIX" is a requirement". This is a reference to the US Government's requirement for POSIX support in many of their tenders. However, related announcements will also mean that the mainframe can be used as a file and compute server for work stations. TCP/IP, NFS and Ethernet options will be supported in this environment, allowing the vast realm of work stations (from Sun, NeXT, HP, DEC and others) that support these protocols to access IBM's big boxes. TCP/IP will also be supported for OS/2 and PC-DOS systems.
This indicates a more "Open" direction from Big Blue, following earlier announcements that Systems Application Architecture (SAA) will support certain AIX facilities, and the addition of OSI to the officially approved list for SAA. The long awaited SAA 91 standard was also released. This adds the treatment of document icons as objects, long supported in all other graphical user interfaces, to SAA. This will mean that you can double-click on a document icon and automatically start up and load the document into it's controlling application. GUIDE's (the IBM user group) Project Group on SAA had already expressed their disappointment