The V operating system (sometimes written V-System) is a discontinued

microkernel In computer science, a microkernel (often abbreviated as μ-kernel) is the near-minimum amount of software that can provide the mechanisms needed to implement an operating system (OS). These mechanisms include low-level address space management, ...

distributed Distribution may refer to: Mathematics *Distribution (mathematics), generalized functions used to formulate solutions of partial differential equations *Probability distribution, the probability of a particular value or value range of a varia ...

operating system An operating system (OS) is system software that manages computer hardware, software resources, and provides common services for computer programs. Time-sharing operating systems schedule tasks for efficient use of the system and may also in ...

that was developed by faculty and students in the

Distributed Systems A distributed system is a system whose components are located on different networked computers, which communicate and coordinate their actions by passing messages to one another from any system. Distributed computing is a field of computer sci ...

Group at

Stanford University Stanford University, officially Leland Stanford Junior University, is a private research university in Stanford, California. The campus occupies , among the largest in the United States, and enrolls over 17,000 students. Stanford is consider ...

from 1981 to 1988, led by Professors

David Cheriton David Ross Cheriton (born March 29, 1951) is a Canadian computer scientist, mathematician, billionaire businessman, philanthropist, and venture capitalist. He is a computer science professor at Stanford University, where he founded and leads the ...

and Keith A. Lantz. V was the successor to the

Thoth Thoth (; from grc-koi, Θώθ ''Thṓth'', borrowed from cop, Ⲑⲱⲟⲩⲧ ''Thōout'', Egyptian: ', the reflex of " eis like the Ibis") is an ancient Egyptian deity. In art, he was often depicted as a man with the head of an ibis or a ...

operating system and Verex

kernel Kernel may refer to: Computing * Kernel (operating system), the central component of most operating systems * Kernel (image processing), a matrix used for image convolution * Compute kernel, in GPGPU programming * Kernel method, in machine learnin ...

that Cheriton had developed in the 1970s. Despite similar names and close development dates, it is unrelated to

UNIX System V Unix System V (pronounced: "System Five") is one of the first commercial versions of the Unix operating system. It was originally developed by AT&T and first released in 1983. Four major versions of System V were released, numbered 1, 2, 3, an ...

Features

The key concepts in V are '' multithreading'' and ''synchronous

message passing In computer science, message passing is a technique for invoking behavior (i.e., running a program) on a computer. The invoking program sends a message to a process (which may be an actor or object) and relies on that process and its supporting i ...

''. The original V terminology uses ''process'' for what is now commonly called a ''thread'', and ''team'' for what is now commonly called a ''

process A process is a series or set of activities that interact to produce a result; it may occur once-only or be recurrent or periodic. Things called a process include: Business and management *Business process, activities that produce a specific se ...

'' consisting of multiple threads sharing an address space. Communication between threads in V uses synchronous message passing, with short, fixed-length messages that can include access rights for the receiver to read or write part of the sender's address space before replying. The same message-passing interface is used both between threads within one process, between threads of different processes within one machine, and between threads on different machines connected by a local

Ethernet Ethernet () is a family of wired computer networking technologies commonly used in local area networks (LAN), metropolitan area networks (MAN) and wide area networks (WAN). It was commercially introduced in 1980 and first standardized in 198 ...

. A thread receiving a message is not required to reply to it before receiving other messages; this distinguished the model from

Ada Ada may refer to: Places Africa * Ada Foah, a town in Ghana * Ada (Ghana parliament constituency) * Ada, Osun, a town in Nigeria Asia * Ada, Urmia, a village in West Azerbaijan Province, Iran * Ada, Karaman, a village in Karaman Province, ...

rendezvous. One common pattern for using the messaging facility is for clients to send messages to a server requesting some form of service. From the client side, this looks much like a

remote procedure call In distributed computing, a remote procedure call (RPC) is when a computer program causes a procedure (subroutine) to execute in a different address space (commonly on another computer on a shared network), which is coded as if it were a normal (l ...

(RPC). The convenience of an automatic stub generator was lacking, but in contrast, the client can pass one parameter by reference, which is not possible with other RPC implementations. From the server side the model differs more from RPC, since by default all client requests are multiplexed onto one server thread. The server is free to explicitly fork threads to handle client requests in parallel, however; if this is done, the server-side model is much like RPC too. V was never an end in itself for the Stanford group; rather, it was used as a vehicle for many different research projects in distributed operating systems and networking. Much like other operating system efforts of its day (such as Sprite), V was a complete system that was mostly self hosting. Many students ran V as the only operating system on their diskless

SUN workstation The SUN workstation was a modular computer system designed at Stanford University in the early 1980s. It became the seed technology for many commercial products, including the original workstations from Sun Microsystems. History In 1979 Xerox do ...

s or

MicroVAX The MicroVAX is a discontinued family of low-cost minicomputers developed and manufactured by Digital Equipment Corporation (DEC). The first model, the MicroVAX I, was introduced in 1983.(announced October 1983) They used processors that implemen ...

workstations. Compiles could be done either on V, or on

VAX VAX (an acronym for Virtual Address eXtension) is a series of computers featuring a 32-bit instruction set architecture (ISA) and virtual memory that was developed and sold by Digital Equipment Corporation (DEC) in the late 20th century. The V ...

Unix Unix (; trademarked as UNIX) is a family of multitasking, multiuser computer operating systems that derive from the original AT&T Unix, whose development started in 1969 at the Bell Labs research center by Ken Thompson, Dennis Ritchie, and ot ...

machines that provided file service in a more stable environment than the ever-changing research system. V did have some notable impacts. After the initial implementation on one computer, the Versatile Message Transaction Protocol (VMTP) was developed to extend the send-receive-reply system call semantics over a

local area network A local area network (LAN) is a computer network that interconnects computers within a limited area such as a residence, school, laboratory, university campus or office building. By contrast, a wide area network (WAN) not only covers a larger ...

. The protocol included multicast support developed by Steve Deering as a graduate student in the group. The

Internet Protocol The Internet Protocol (IP) is the network layer communications protocol in the Internet protocol suite for relaying datagrams across network boundaries. Its routing function enables internetworking, and essentially establishes the Internet. IP h ...

layer to support this evolved into the

IP multicast IP multicast is a method of sending Internet Protocol (IP) datagrams to a group of interested receivers in a single transmission. It is the IP-specific form of multicast and is used for streaming media and other network applications. It uses speci ...

standard. The V system was used for

graphical user interface The GUI ( "UI" by itself is still usually pronounced . or ), graphical user interface, is a form of user interface that allows users to interact with electronic devices through graphical icons and audio indicator such as primary notation, inste ...

(GUI) research. The Virtual Graphics Terminal Service (VGTS) provided a modular

windowing system In computing, a windowing system (or window system) is software that manages separately different parts of display screens. It is a type of graphical user interface (GUI) which implements the WIMP (windows, icons, menus, pointer) paradigm for ...

for both local and remote applications. The little-known

W Window System The W window system is a discontinued windowing system and precursor in name and concept to the modern X Window System window system. W was originally developed at Stanford University by Paul Asente and Brian Reid for the V operating system. In ...

got its name because it was first hosted on the V operating system, and the better-known

X Window System The X Window System (X11, or simply X) is a windowing system for bitmap displays, common on Unix-like operating systems. X provides the basic framework for a GUI environment: drawing and moving windows on the display device and interacting wit ...

in turn got its name because its first version was based partly on W. V also spawned another pure microkernel effort at

Apple Computer Apple Inc. is an American multinational technology company headquartered in Cupertino, California, United States. Apple is the largest technology company by revenue (totaling in 2021) and, as of June 2022, is the world's biggest company b ...

known as

Vanguard The vanguard (also called the advance guard) is the leading part of an advancing military formation. It has a number of functions, including seeking out the enemy and securing ground in advance of the main force. History The vanguard derives fr ...

, which added a number of improvements to the basic system. Vanguard later disappeared in a reorganization. The

Tektronix Tektronix, Inc., historically widely known as Tek, is an American company best known for manufacturing test and measurement devices such as oscilloscopes, logic analyzers, and video and mobile test protocol equipment. Originally an independent ...

VM700 television measurement instrument was developed in a networked V environment in the late 1980s and ran a lightly modified version of the V operating system; this device was manufactured and sold for many years.

Commands

The following is a list of workstation commands that are supported by the V operating system version 6.0

command-line interface A command-line interpreter or command-line processor uses a command-line interface (CLI) to receive commands from a user in the form of lines of text. This provides a means of setting parameters for the environment, invoking executables and pro ...

.V-System 6.0 Reference Manual
/ref> * addcorr * amaze * ar * biopsy * bitcompile * bits * boise * build *

cat The cat (''Felis catus'') is a domestic species of small carnivorous mammal. It is the only domesticated species in the family Felidae and is commonly referred to as the domestic cat or house cat to distinguish it from the wild members of ...

* cc68 * cd * checkers * checkexecs * ci * clear * clock * co * cp * cpdir * cx * dale *

date Date or dates may refer to: *Date (fruit), the fruit of the date palm (''Phoenix dactylifera'') Social activity *Dating, a form of courtship involving social activity, with the aim of assessing a potential partner ** Group dating *Play date, a ...

* debug * debugvgts * define * delcorr * delexec * destroy *

diff In computing, the utility diff is a data comparison tool that computes and displays the differences between the contents of files. Unlike edit distance notions used for other purposes, diff is line-oriented rather than character-oriented, but it ...

* do * domake * dopar * doseq * draw *

echo In audio signal processing and acoustics, an echo is a reflection of sound that arrives at the listener with a delay after the direct sound. The delay is directly proportional to the distance of the reflecting surface from the source and the list ...

* fexecute * freemem * gftodvi * gftyoe *

grep grep is a command-line utility for searching plain-text data sets for lines that match a regular expression. Its name comes from the ed command ''g/re/p'' (''globally search for a regular expression and print matching lines''), which has the sam ...

* hack * ident * instances * internetserver * iphost * killprog * listdir * listdesc *

login In computer security, logging in (or logging on, signing in, or signing on) is the process by which an individual gains access to a computer system by identifying and authenticating themselves. The user credentials are typically some form ...

logout In computer security, logging in (or logging on, signing in, or signing on) is the process by which an individual gains access to a computer system by identifying and authenticating themselves. The user credentials are typically some form ...

mail The mail or post is a system for physically transporting postcards, letter (message), letters, and parcel (package), parcels. A postal service can be private or public, though many governments place restrictions on private systems. Since the mid ...

* memserver * mf * migrateprog * mon * name * newterm * pagemode *

password A password, sometimes called a passcode (for example in Apple devices), is secret data, typically a string of characters, usually used to confirm a user's identity. Traditionally, passwords were expected to be memorized, but the large number of ...

* pc68 *

pwd In Unix-like and some other operating systems, the pwd command (''print working directory'') writes the full pathname of the current working directory to the standard output. Implementations Multics had a pwd command (which was a short name of ...

* pwx * Q * query * queryexec * ranlib68 *

rcs RCS may refer to: Organisations *Racing Club de Strasbourg Alsace * Radio Corporation of Singapore *Radcliffe Choral Society * Rawmarsh Community School *Red Crescent Society *Red Cross Society * Representation of Czechs and Slovaks, a football t ...

* rcsdiff * rcsmerge * rename * rlog * rm *

sed sed ("stream editor") is a Unix utility that parses and transforms text, using a simple, compact programming language. It was developed from 1973 to 1974 by Lee E. McMahon of Bell Labs, and is available today for most operating systems. sed w ...

* serial * show *

sleep Sleep is a sedentary state of mind and body. It is characterized by altered consciousness, relatively inhibited sensory activity, reduced muscle activity and reduced interactions with surroundings. It is distinguished from wakefulness by a de ...

sort Sort may refer to: * Sorting, any process of arranging items in sequence or in sets ** Sorting algorithm, any algorithm for arranging elements in lists ** Sort (Unix), a Unix utility which sorts the lines of a file ** Sort (C++), a function in the ...

* startexec * storagestats * stuffboot *

tail The tail is the section at the rear end of certain kinds of animals’ bodies; in general, the term refers to a distinct, flexible appendage to the torso. It is the part of the body that corresponds roughly to the sacrum and coccyx in mammals, r ...

talk Talk may refer to: Communication * Communication, the encoding and decoding of exchanged messages between people * Conversation, interactive communication between two or more people * Lecture, an oral presentation intended to inform or instruct ...

telnet Telnet is an application protocol used on the Internet or local area network to provide a bidirectional interactive text-oriented communication facility using a virtual terminal connection. User data is interspersed in-band with Telnet control i ...

* telnetserver * testexcept * timeipc * timekernel *

tsort The tsort program is a command line utility on Unix and Unix-like platforms, that performs a topological sort on its input. , it is part of the POSIX.1 standard. History According to its info page, this command was initially written for providi ...

* type * undefine * ved * vemacs * w * wc * wh * whi

References

External links

V system documentation
at Bitsavers.org {{Distributed operating systems Microkernels Stanford University Discontinued operating systems Distributed operating systems Microkernel-based operating systems