Bringing to the generality of its Unix users the benefit of work it has had to do to adapt its Towers to be the basis of its new generation of retail and banking systems, NCR Corp on Friday added a suite of real-time transaction processing modules to the Tower implementation of Unix System V. The General Purpose Transaction Facility compromises neither portability of time sharing applications nor upgradability of systems, NCR insists. The modules merely enhance System V without altering it, enabling Towers to respond to a request in under 17mS. A suite of utilities and procedures, General Purpose Transaction Facility enables the Towers to support real-time and transaction processing applications and to speed the process of CPU resource allocation. It eliminates pagination for processes declared resident, manages shared memory with high-speed semaphores, and sets priorities for disk accesses as well as improving inter process communications by means of specialised message transfer files. In contrast, with Unix alone, all pro-cesses are allocated the same proportion of CPU resources and given equal priority so that as the system becomes more heavily loaded, everything slows down. With the NCR extension, the system can be tuned to give priority to critical parts of the application clearly an essential capability when the machines are used to support a network of banking or point-of-sale terminals. It requires version 1.03 of Unix for the Tower, and a 32/400 or 32/600 processor. It is planned to be available in the US in February.