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Plumber (Plan 9)
The plumber, in the Plan 9 from Bell Labs and Inferno operating systems, is a mechanism for reliable uni- or multicast inter-process communication of formatted textual messages. It uses the Plan 9 network file protocol, 9P, rather than a special-purpose IPC mechanism. Any number of clients may listen on a named port (a file) for messages. Ports and port routing are defined by plumbing rules. These rules are dynamic. Each listening program receives a copy of matching messages. For example, if the data /sys/lib/plumb/basic is plumbed with the standard rules, it is sent to the edit port. The port will write a copy of the message to each listener. In this case, all running editors will interpret this message as a file name, and open the file. The plumber is the 9P file server that provides this service. Clients may use libplumb to format messages. Since the messages are 9P, they are network transparent. See also * Pipeline (software) External links * * * *"Plumbing and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plan 9 From Bell Labs
Plan 9 from Bell Labs is a distributed operating system which originated from the Computing Science Research Center (CSRC) at Bell Labs in the mid-1980s and built on UNIX concepts first developed there in the late 1960s. Since 2000, Plan 9 has been free and open-source. The final official release was in early 2015. Under Plan 9, UNIX's ''everything is a file'' metaphor is extended via a pervasive network-centric filesystem, and the cursor-addressed, terminal-based I/O at the heart of UNIX-like operating systems is replaced by a windowing system and graphical user interface without cursor addressing, although rc, the Plan 9 shell, is text-based. The name ''Plan 9 from Bell Labs'' is a reference to the Ed Wood 1957 cult science fiction Z-movie '' Plan 9 from Outer Space''. The system continues to be used and developed by operating system researchers and hobbyists. History Plan 9 from Bell Labs was originally developed, starting in the late 1980s, by members of the Computing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inferno (operating System)
Inferno is a distributed operating system started at Bell Labs and now developed and maintained by Vita Nuova Holdings as free software under the MIT License. Inferno was based on the experience gained with Plan 9 from Bell Labs, and the further research of Bell Labs into operating systems, languages, on-the-fly compilers, graphics, security, networking and portability. The name of the operating system, many of its associated programs, and that of the current company, were inspired by Dante Alighieri's ''Divine Comedy''. In Italian, ''Inferno'' means "hell", of which there are nine circles in Dante's ''Divine Comedy''. Design principles Inferno was created in 1995 by members of Bell Labs' Computer Science Research division to bring ideas derived from their previous operating system, Plan 9 from Bell Labs, to a wider range of devices and networks. Inferno is a distributed operating system based on three basic principles: * Resources as files: all Resource (computer science), re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Unicast
Unicast is data transmission from a single sender (red) to a single receiver (green). Other devices on the network (yellow) do not participate in the communication. In computer networking, unicast is a one-to-one transmission from one point in the network to another point; that is, one sender and one receiver, each identified by a network address. Unicast is in contrast to multicast and broadcast which are one-to-many transmissions. Internet Protocol unicast delivery methods such as Transmission Control Protocol (TCP) and User Datagram Protocol (UDP) are typically used. See also * Anycast * Broadcast, unknown-unicast and multicast traffic * IP address * IP multicast * Routing Routing is the process of selecting a path for traffic in a network or between or across multiple networks. Broadly, routing is performed in many types of networks, including circuit-switched networks, such as the public switched telephone netw ... References External links * * Internet archit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multicast
In computer networking, multicast is group communication where data transmission is addressed to a group of destination computers simultaneously. Multicast can be one-to-many or many-to-many distribution. Multicast should not be confused with physical layer point-to-multipoint communication. Group communication may either be application layer multicast or network-assisted multicast, where the latter makes it possible for the source to efficiently send to the group in a single transmission. Copies are automatically created in other network elements, such as routers, switches and cellular network base stations, but only to network segments that currently contain members of the group. Network assisted multicast may be implemented at the data link layer using one-to-many addressing and switching such as Ethernet multicast addressing, Asynchronous Transfer Mode (ATM), point-to-multipoint virtual circuits (P2MP) or InfiniBand multicast. Network-assisted multicast may also be impl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inter-process Communication
In computer science, inter-process communication or interprocess communication (IPC) refers specifically to the mechanisms an operating system provides to allow the processes to manage shared data. Typically, applications can use IPC, categorized as clients and servers, where the client requests data and the server responds to client requests. Many applications are both clients and servers, as commonly seen in distributed computing. IPC is very important to the design process for microkernels and nanokernels, which reduce the number of functionalities provided by the kernel. Those functionalities are then obtained by communicating with servers via IPC, leading to a large increase in communication when compared to a regular monolithic kernel. IPC interfaces generally encompass variable analytic framework structures. These processes ensure compatibility between the multi-vector protocols upon which IPC models rely. An IPC mechanism is either synchronous or asynchronous. Synchr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
9P (protocol)
9P (or the Plan 9 Filesystem Protocol or Styx) is a network protocol developed for the Plan 9 from Bell Labs distributed operating system as the means of connecting the components of a Plan 9 system. Files are key objects in Plan 9. They represent windows, network connections, processes, and almost anything else available in the operating system. 9P was revised for the 4th edition of Plan 9 under the name 9P2000, containing various improvements. Some of the improvements made are the removal of certain filename restrictions, the addition of a 'last modifier' metadata field for directories, and authentication files. The latest version of the Inferno operating system also uses 9P2000. The Inferno file protocol was originally called Styx, but technically it has always been a variant of 9P. A server implementation of 9P for Unix, called u9fs, is included in the Plan 9 distribution. A 9P OS X client kernel extension is provided by Mac9P. A kernel client driver implementing 9P with so ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pipeline (software)
In software engineering, a pipeline consists of a chain of processing elements ( processes, threads, coroutines, functions, ''etc.''), arranged so that the output of each element is the input of the next; the name is by analogy to a physical pipeline. Usually some amount of buffering is provided between consecutive elements. The information that flows in these pipelines is often a stream of records, bytes, or bits, and the elements of a pipeline may be called filters; this is also called the pipes and filters design pattern. Connecting elements into a pipeline is analogous to function composition. Narrowly speaking, a pipeline is linear and one-directional, though sometimes the term is applied to more general flows. For example, a primarily one-directional pipeline may have some communication in the other direction, known as a ''return channel'' or ''backchannel,'' as in the lexer hack, or a pipeline may be fully bi-directional. Flows with one-directional tree and directed acyc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rob Pike
Robert "Rob" Pike (born 1956) is a Canadian programmer and author. He is best known for his work on the Go programming language and at Bell Labs, where he was a member of the Unix team and was involved in the creation of the Plan 9 from Bell Labs and Inferno operating systems, as well as the Limbo programming language. He also co-developed the Blit graphical terminal for Unix; before that he wrote the first window system for Unix in 1981. Pike is the sole inventor named in US patent 4,555,775. Over the years Pike has written many text editors; sam and acme are the most well known and are still in active use and development. Pike, with Brian Kernighan, is the co-author of '' The Practice of Programming'' and '' The Unix Programming Environment''. With Ken Thompson he is the co-creator of UTF-8. Pike also developed lesser systems such as the vismon program for displaying faces of email authors. Pike also appeared once on ''Late Night with David Letterman'', as a technical a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
