VME (Virtual Machine Environment) is a mainframe operating system developed by the UK company International Computers Limited (ICL, now part of the Fujitsu group).
A number of different feasibility and design studies were carried out within ICL, the three most notable being: The chief architect of VME/B was Brian Warboys, who subsequently became professor of software engineering at the University of Manchester.
VME/B was viewed as primarily competing with the System/370 IBM mainframe as a commercial operating system, and adopted the EBCDIC character encoding.
[4] VME/K (originally known internally as "System T" for "Tiny") was developed independently (according to Campbell-Kelly, "on a whim of Ed Mack"), and was delivered later with the smaller mainframes such as the 2960.
ICL had sold a large system to the European Space Agency to process data from Meteosat at its operation centre in Darmstadt.
This provided the opportunity to drop some obsolescent features, which remained available to customers who needed them in the form of the "BONVME" option.
[6][7][8] In 2007 Fujitsu announced a VME version run as a hosted subsystem, called superNova, within Microsoft Windows, or SUSE or Red Hat Enterprise Linux on x86-64 hardware.
Orthogonally to the access levels, the operating system makes resources available to applications in the form of a Virtual Machine (VM).
Run-time exceptions, referred to as contingencies, are captured by the Object Program Error Handler (OPEH), which can produce a report (equivalent to a stack trace), either interactively or written to a journal.
[16] Commands illustrated in this fragment include WHENEVER (declares error handling policy), ASSIGN_LIBRARY (binds a local name for a file directory), DELETE_FILE (Makes a permanent file temporary, and it is then deleted at the END of the block), S3_COMPILE (compiles a program written in S3: this command breaks the usual verb-noun convention), NEW_MESSAGE_TEXT_MODULE (creates a module containing parameterized error messages suitable for localization) and COMPILE_SCL, which compiles an SCL program into object code.
This led to the UK Government's Central Computing and Telecommunications Agency (CCTA) funding Project Spaceman in the mid 1980s for ICL Defence Technology Centre (DTC) to develop an enhanced security variant of VME.
[17] ICL launched this as a pair of complementary products, with the commercial release being called High Security Option (HSO), and the public sector release, including Government Furnished Encryption (GFE) technologies, being called Government Security Option (GSO).
ICL had originally announced a hosted Unix facility for VME in 1985, with availability and support for strategic applications to arrive within eighteen months.
[19] Limited availability was then announced to existing VME customers, with others being guided towards ICL's Clan range of Unix departmental systems.
[23] The Series 39 range introduced Nodal Architecture, a novel implementation of distributed shared memory that can be seen as a hybrid of a multiprocessor system and a cluster design.
From its earliest days, VME was developed with the aid of a software engineering repository system known as CADES, originally designed and managed by David Pearson (computer scientist) and built for the purpose using an underlying IDMS database.
CADES is not merely a version control system for code modules: it manages all aspects of the software lifecycle from requirements capture, design methodology and specification through to field maintenance.
CADES was used in VME module development to hold separate definitions of data structures (Modes), constants (Literals), procedural interfaces and the core algorithms.
For many years the large majority of VME users wrote applications in COBOL, usually making use of the IDMS database and the TPMS transaction processing monitor.
Later, in the mid 1980s, compilers for C became available, both within and outside the Unix subsystem, largely to enable porting of software such as relational database systems.
Many of the compilers used a module named ALICE [Assembly Language Internal Common Environment] and produced an early form of precompiled code (P-Code) termed ROSE, making compiled Object Module Format (OMF) libraries loadable on any machine in the range.
This is a high level language based in many ways on Algol 68, but with data types and low-level functions and operators aligned closely with the architecture of the 2900 series.
This was used for the development of VME/K, whose designers were not confident that a high-level language could give adequate performance, and also for the IDMS database system on account of its origins as a third-party product.
Neither S3 nor SFL was ever promoted as a commercial development tool for end-user applications, as neither were normally delivered as a standard part of the operating system, nor were they explicitly marketed as products in their own right.
Because the 4GL and other tools such as the screen designer work only with the DDS dictionary, which also holds the database schemas, there is considerable reuse of metadata that is rarely achieved with other 4GLs.