History of Unix

The history of Unix began in 1965, when as part of the "Fall Joint Computer Conference " some essays on a new created operating system called " Multics " were published. Later, from the Unix operating system Multics, which was then further developed in numerous derivatives.

  • 2.1 Free Software

The 1970

In 1965, the case Joint Computer Conference were published some essays on a new created operating system called Multics in the frame. Behind Multics was a consortium of MIT, General Electric, Bell Labs and Honeywell. Also involved was IBM, should be developed in the programming language PL / I Multics.

But the project failed Multics (although it was further developed until the 1980s); expectations of Multics were partially single coated, the hardware could handle this time no system of this size in a reasonable rate. By 1969, the Bell Labs withdrew as a consequence of the project. Dennis Ritchie, one of the later creator of Unix and party to the Multics project, said in an article to published in 1979 as follows:

" ... The problem which the Increasing obviousness of the failure of Multics to deliver promptly any sort of usable system ... "

" ... The problem was the increasing obviousness that Multics would fail is to provide some form of benutzbarem system in the foreseeable future ... "

But Ritchie 's team, including Ken Thompson, Douglas McIlroy, and Joseph Ossanna was not on. It was all about them, to have a multi-user system that allowed them not only to program together, but also on the basis of a real community could emerge. For this purpose, the system had to support some technical specialties, who were then not self-evident, for example, that multiple users could work on files simultaneously without getting in each other 's way.

While the team tried in vain to convince Bell Labs from buying a suitable machine, at the same time began the technical preparation: On the concepts memo notes and tables to a file system have been developed, which was later to become one of the core pieces of Unix. Thompson also developed some prototypes of a file system and a primitive kernels that were run on a GE 645. He had to adjust the project but after it became clear that the GE -645 would be removed in the foreseeable future from the labs.

He finally found a largely unused PDP -7, to which he wanted to port a previously developed for Multics and gecos game called Space Travel. The company turned out to be more complicated than you think because for the PDP -7 was present not own development system and so had to take place all development under gecos, which then produced the PDP - 7 code.

To remedy the situation, Thompson began with the help of Ritchie, the implementation of the previously designed file system together with a primitive process management and then a number of smaller programs, which should make the system more usable: Editor, smaller file management programs, and a simple command line interpreter (shell ) until the system was finally equipped sufficient to develop directly on the PDP -7 without the GECOS detour.

The PDP -7 was at that time already on the way out and was not even the team, but eventually proved to be the efforts to procure their own computer for Unix development, to be successful, and the procurement of a PDP -11 was commissioned. Unix was ported rapidly, and the system has been used successfully since 1971 in the Patent Office of Bell Labs as a text processing system. The system was due to the circumstances, remarkably small compared to today's operating systems: It consisted of 16 KB of memory for the system, 8 KB for user programs, a 512 -KB disk, and files could be up to 64 KB in size.

In 1970, Peter Neumann had the project name Unics ( UNiplexed Information and Computing Service ) .. Brian W. Kernighan coined remarked to the system Unics slightly mocking, alluding to Multics, since it only supported up to two users: " emasculated Multics is Unics. " ( emasculated Multics is Unics ). The name should be shortened later to Unix. The spelling UNIX was issued in 1974, according to Ritchie out of sheer enthusiasm for small caps: " ... we had a new typesetter and troff had just been invented and we were intoxicated by being able to produce small caps. "

The use of the patent office gave the group enough credibility so that Unix was interesting as a project for the Bell Labs and to justify the purchase of a PDP 11/74, and the AT & T Unix Systems Group (later: Unix Systems Group) as an official project of the Bell Labs was founded.

Porting to C

Parallel began a development that was crucial to the later success of Unix: the evolution of the C language

Ritchie and Thompson 1971 developed an interpreted programming language for the PDP -7 called B, which was based on BCPL. Ritchie added the language on the PDP -11 data types, called it first NB ( New B) and began to develop a compiler for the language.

1972 now began the rebuilding of Unix in this language, which now received the name C to the future to facilitate the porting of Unix to new computer. The port was completed in 1973 and was named Unix V4.


At the same time Unix, to extend the concept of pipes at the suggestion of Douglas McIlroy. Pipes connect small programs and allow to further process the result of a program under a single command line statement in another program, and later discovered one of the most important core elements of Unix, since only they allowed the concept of small specialized tools that perform exactly one task.

Unix is leaving Bell Labs

Unix was now within the Bell Labs on more than 25 computers, and a lecture in 1973 on a ACM symposium it was first known outside of Bell Labs. The lecture then appeared in revised form in 1974 as The UNIX Time - Sharing System, Communications of the ACM. The interest in Unix rose outside of Bell Labs at enormous.

The 1956 completed Consent Decree forbade AT & T, the parent company of Bell Labs, entering new markets such as the computer market. For this reason, Unix was made ( in 1975 current version 6) for only the price of the disk number of universities is available, along with the complete source code. 1976 wrote of Australian Professor John Lions detailed comments to the source code of Unix V6, which became famous as the Lions Book.

It was especially popular Unix at the University of California at Berkeley, where immediately a number of improvements to Unix were developed. When Ken Thompson in 1976 took up a visiting professorship in the newly established computer science department at Berkeley, the University was definitively one of the most important centers of Unix development. The university later made ​​important contributions to Unix, such as support for TCP / IP, which were later adopted into the official version of Unix from AT & T.

Starting in 1977, the University published under the direction of Bill Joy own Unix Distribution: Berkeley Software Distribution (BSD ).

In 1978, over 600 computers with UNIX operating systems have been operated.

In 1979, AT & T was the last version of UNIX with free source code, namely UNIX V7 published. UNIX V7 represents a turning point in the history of UNIX, since AT & T first attempted at a commercial marketing on a larger scale.

Microsoft acquired in 1979 a Unix license and began under the name Xenix work on porting among other things, Intel 8086, Motorola 68000 and Zilog Z8000 processors. On the basis of Xenix Siemens created in 1984, the first German version of Unix for Intel 80186 CPUs under the name Sinix.

In the late 1980s Microsoft developed together with IBM OS / 2 (later split into IBM's OS / 2 and Microsoft Windows NT). Since you would have had with OS / 2 (or Windows NT) and Xenix two server operating systems on offer, which would have made ​​competing with each other, Microsoft decided in 1987, the rights to Xenix to the company Santa Cruz Operations (short SCO, later called Tarantella ) for sale, which had since 1983 licensee of Xenix.

The 1980

In 1980, the first port of Unix V7 on a 32- bit machine, the VAX, UNIX 32V and 3BSD appeared.

In the course of the 1980s were UNIX V8, V9 and V10 still to be developed, but presented only at a few universities, although written descriptions of work created in these versions. The considerations in this work but ultimately led to the development of the operating system plan 9

The 1980s are characterized by the beginning of the great " Unix wars" and the commercialization of Unix. AT & T officially entered the computer market and began in 1983 to commercialize a system based on Unix V7 system, called System V, while the University of Berkeley 4.2BSD published at the same time, brought the new features such as TCP / IP and reliable signals with it. Meanwhile, DARPA was interested in Unix and supported from now on the developments in Berkeley financially.

In order to prevent further splitting, the POSIX standardization project was launched, which should define a uniform interface for Unix. 1988 was finally published POSIX.1 (now also an IEEE standard under number 1003.1 ).

A number of (partly changing ) alliances began to form, the favored several Unix versions:

  • Open Software Foundation: The OSF was founded in 1985, partly because of the opinion of the participants that the POSIX standard AT & T would prefer too strong, partly due to fears that AT & T and Sun Microsystems, who co-operate in 1987, divide the market among themselves could. Founding members of the OSF were, among others, DEC, Siemens, HP and IBM. The consortium had set itself the goal to publish a common Unix under the name of OSF / 1.
  • Unix International: UI was in direct response to the OSF founded by supporters of the AT & T line, such as Olivetti, Unisys, and even AT & T and Sun Microsystems.
  • X / Open: Originally founded in 1983 under the name Bison from a number of European companies such as Bull, Siemens, Olivetti, to better represent common European interests against the U.S. companies can was later renamed the consortium with the inclusion of U.S. companies.

While OSF / 1 was not completed until the 1990s, published in AT & T and UI further improvements to Unix System V. The differences between the OSF - line and UI were publicly further emphasizes to the market, but the program code of System V bridged with any subsequent release, the differences - with system V.4 includes practically all major innovations 1989 from BSD and Xenix system V in.

1987 developed the teaching in Amsterdam American computer scientist Professor Andrew S. Tanenbaum unixoides an operating system called Minix. Minix should serve the ruler to illustrate to his students the basics of an operating system, as the increasingly restrictive disabled AT & T licenses for Unix him at work. Minix itself never gained great importance, however, inspired Linus Torvalds to work on the Linux kernel.

1989 " UNIX System V Release 4" was announced and released. It was followed later " Release 4.2 " and " Release 5 " section.

Free Software

In 1983 Richard Stallman, angered by the Proprietarisierung of Unix, with the work on his own, Unix-like operating system called GNU, and cried with the release of the GNU Manifesto in 1985 an ever -increasing free software movement to life.

The 1990s

In 1990 " 4.3BSD Reno ."

In 1991, Linus Torvalds on October 5, the operating system kernel Linux with the version number before 0:02. 4.3BSD NET / 2 appeared, and Sun Microsystems Solaris 1.0 published. A group of BSD developers left the University of Berkeley and founded Berkeley Software Design ( BSDI ).

Published in 1992, Billy Jolitz 386BSD, a port of 4.3BSD NET / 2 on the Intel i386 processor and Sun Microsystems released the first version of Solaris (operating system ) for the Intel i386 processor.

1993 appeared the version " 4.4BSD ", and it began the development of FreeBSD and NetBSD, based on " 386BSD ". Published BSDI BSD / OS, a commercial version of BSD.

On 16 June 1993, Novell acquired by AT & T Unix System Laboratories ( USL ).

X / Open acquired in 1993 by Novell, the exclusive right to use the trademark UNIX. Goal was a cross-vendor standard, the Single UNIX Specification. Your compliance is a prerequisite for licensing the name " UNIX", which thus received a new meaning.

In 1994, after copyright disputes between Novell and USL USL - BSDI on all developments based source code from 4.4BSD away, and it came to the release of " 4.4BSD lite ". The free BSDs also brought out new, based on " 4.4BSD lite " versions.

Furthermore, it came to the so-called desktop wars. See: Common Open Software Environment ( COSE ): HP, IBM, SCO, Sunsoft, Univel / Novell, USL → CDE, Motif, Wabi, Looking Glass.

1995 Novell sold as part of a long-term cooperation be UNIX business to SCO, but kept apart from the trademark intellectual property, including copyrights and patents.

In 1996, OSF and X / Open merged to form the Open Group. The Open Group became the owner of the trademark UNIX.

In 1997, the Open Group published the standard " Single UNIX Spec / 2", which is now real time, threads, and 64 -bit processors supported.

Since 2000

In 2000, Darwin was the foundation of Mac OS X released, with Mach as the kernel.

In May 2001, bought Caldera, a provider of a rather little-known Linux distribution, the Unix division of Santa Cruz Operations (SCO ). SCO named thereupon order in Tarantella. In August 2002 Caldera changed its name to The SCO Group, as the brand name SCO was known as one's own.

2002: ISO / IEC 9945:2002 ( Single Unix Spec )

Caused a stir 2003-2007 complaints of the SCO Group against IBM and some of its clients: IBM had to incorporate SCO patents, core technologies and proprietary ingredients of Unix into the Linux kernel. The assertions proved in court, however, untenable, especially SCO was also not as alleged since 1995 owner of the copyright of the Unix code.

More about it here: SCO against Linux