Anonymous pipe

In computer science, an anonymous pipe is a simplex FIFO communication channel that may be used for one-way interprocess communication (IPC). An implementation is often integrated into the operating system's file IO subsystem. Typically a parent program opens anonymous pipes, and creates a new process that inherits the other ends of the pipes, or creates several new processes and arranges them in a pipeline.

Full-duplex (two-way) communication normally requires two anonymous pipes.

Pipelines are supported in most popular operating systems, from Unix and DOS onwards, and are created using the "|" character.

Unix

Pipelines are an important part of many traditional Unix applications and support for them is well integrated into most Unix-like operating systems. Pipes are created using the pipe system call, which creates a new pipe and returns a pair of file descriptors referring to the read and write ends of the pipe. Many traditional Unix programs are designed as filters to work with pipes.

Pipeline (Unix)

In Unix-like computer operating systems (and, to some extent, Microsoft Windows), a pipeline is a set of processes chained by their standard streams, so that the output of each process (stdout) feeds directly as input (stdin) to the next one. Filter programs are often used in this configuration.

The concept of pipelines was invented by Douglas McIlroy at Unix's ancestral home of Bell Labs, prior to the actual invention of the operating system, and implemented in Unix at his insistence, shaping its toolbox philosophy. It is named by analogy to a physical pipeline. The standard shell syntax for pipelines is to list multiple programs to invoke in one command, separated by vertical bars:

Each program is assumed to take input and give output on its standard streams. Each "|" tells the shell to connect the standard output of the left program to the standard input of the right program by an inter-process communication mechanism called an (anonymous) pipe, implemented in the operating system. Since pipes are unidirectional, data flows through the pipeline from left to right.

Organ pipe

An organ pipe is a sound-producing element of the pipe organ that resonates at a specific pitch when pressurized air (commonly referred to as wind) is driven through it. Each pipe is tuned to a specific note of the musical scale. A set of organ pipes of similar timbre tuned to a scale is known as a rank or a stop.

Construction

Materials

Organ pipes are generally made out of either metal or wood. Very rarely, glass, porcelain, plastic, paper, Papier-mâché, or even stone pipes may be seen. A historical organ in the Philippines has pipes made exclusively of bamboo.

Metal

Metal pipes are usually made of lead; for increased rigidity it is alloyed with tin along with trace amounts of antimony and copper. The percentage of each metal in the alloy influences the characteristics of the resulting pipe. A high proportion of tin results in a slightly brighter colouring. In addition, high amounts of tin give a gleaming and long-lasting polish, which may be desired if the pipe is clearly visible. The cost of each metal is also a factor, as tin is more expensive than lead. Cost considerations may also lead to the use of the inferior rolled zinc especially for the lower tones that take a lot of material. In addition, pipes have been made of many metals, including copper, aluminium, gold electroplate, silver, brass, and iron.

Gas

Gas is one of the four fundamental states of matter (the others being solid, liquid, and plasma). A pure gas may be made up of individual atoms (e.g. a noble gas like neon), elemental molecules made from one type of atom (e.g. oxygen), or compound molecules made from a variety of atoms (e.g. carbon dioxide). A gas mixture would contain a variety of pure gases much like the air. What distinguishes a gas from liquids and solids is the vast separation of the individual gas particles. This separation usually makes a colorless gas invisible to the human observer. The interaction of gas particles in the presence of electric and gravitational fields are considered negligible as indicated by the constant velocity vectors in the image. One type of commonly known gas is steam.

The gaseous state of matter is found between the liquid and plasma states, the latter of which provides the upper temperature boundary for gases. Bounding the lower end of the temperature scale lie degenerative quantum gases which are gaining increasing attention. High-density atomic gases super cooled to incredibly low temperatures are classified by their statistical behavior as either a Bose gas or a Fermi gas. For a comprehensive listing of these exotic states of matter see list of states of matter.

Gas (musician)

Gas is a music project of Wolfgang Voigt (born 1961), a Cologne, Germany-based electronic musician. Voigt cites his youthful LSD experiences in the Königsforst, a German forest situated near his hometown of Köln, as the inspiration behind his work under the name Gas. He has claimed that the intention of the project is to "bring the forest to the disco, or vice-versa".

Aliases and projects

Voigt is known for his numerous, nearly inexhaustible list of one-off projects and aliases. Of these, his best known is arguably Gas, a project that saw the marriage of ambient music and 4/4 techno.

Other names under which Voigt has released music include, but are not limited to, All, Auftrieb, Brom, C.K. Decker, Centrifugal Force, Crocker, Dextro NRG, Dieter Gorny, Digital, Dom, Doppel, Filter, Freiland, Fuchsbau, Gelb, Grungerman, Kafkatrax, Love Inc., M:I:5, Mike Ink, Mint, Panthel, Popacid, Riss, RX7, Split Inc., Strass, Studio 1, Tal, Vinyl Countdown, W.V., Wassermann, and X-Lvis.

Characteristics

Gas (album)

Gas is the debut album by Wolfgang Voigt's Gas project. It is the second release under the Gas name, preceded only by the Modern EP. It was released on 29 November, 1996 on the Mille Plateaux label. Like all Gas albums, the tracks are untitled. Along with Modern, it is unusual in that the artwork does not share the unifying forest theme common to all other Gas releases.

Track listing