Friday, November 13, 2015

UNIX (tm) Version History

Well this about history of UNIX,main reason to write this is because of confusion about various versions and how they came to be.What ever given below are not my keystrokes rather from distributed sources like Wikipedia and others. What make this blog different , well i have compiled only necessary information for understanding version confusion.

Unix (officially trademarked as UNIX, sometimes also written as Unix with small caps) is a computer operating system originally developed in 1969 by a group of AT&T employees at Bell Labs, including Ken Thompson, Dennis Ritchie, Douglas McIlroy, and Joe Ossanna.As of 2007, the owner of the trademark is The Open Group.Only systems fully compliant with and certified to the Single UNIX Specification are qualified to use the trademark; others are called "Unix system-like" or "Unix-like".Commercial start ups, the most notable of which are Solaris, HP-UX, AIX, and Mac OS X.

AT&T made Unix available to universities and commercial firms, as well as the United States government under licenses. The licenses included all source code including the machine-dependent parts of the kernel, which were written in PDP-11 assembly code. Copies of the annotated Unix kernel sources circulated widely in the late 1970s in the form of a much-copied book by John Lions of the University of New South Wales, the Lions' Commentary on UNIX 6th Edition, with Source Code, which led to considerable use of Unix as an educational example.

Version 5 and especially Version 6 led to a plethora of different Unix versions. Version 7 Unix, the last version of Research Unix to be released widely, was released in 1979. Versions 8, 9 and 10 were developed through the 1980s but were only released to a few universities.AT&T licensed UNIX System III, based largely on Version 7, for commercial use, the first version launching in 1982. This also included support for the VAX. AT&T continued to issue licenses for older Unix versions.To end the confusion between all its differing internal versions, AT&T combined them into UNIX System V Release 1.

Since the newer commercial UNIX licensing terms were not as favorable for academic use as the older versions of Unix, the Berkeley researchers continued to develop BSD Unix as an alternative to UNIX System III and V.the most important aspect of the BSD development effort was the addition of TCP/IP network code to the mainstream Unix kernel.

Other companies began to offer commercial versions of the UNIX System for their own mini-computers and workstations. Most of these new Unix flavors were developed from the System V base under a license from AT&T; however, others were based on BSD instead. One of the leading developers of BSD, Bill Joy, went on toco-found Sun Microsystems in 1982 and created SunOS for their workstation computers.

In 1991, a group of BSD developers (Donn Seeley, Mike Karels, Bill Jolitz, and Trent Hein) left the University of California to found Berkeley Software Design, Inc (BSDI). BSDI produced a fully functional commercial version of BSD Unix for the inexpensive and ubiquitous Intel platform, which started a wave of interest in the use of inexpensive hardware for production computing. Shortly after it was founded, Bill Jolitz left BSDI to pursue distribution of 386BSD, the free software ancestor of FreeBSD, OpenBSD, and NetBSD.A free derivative of BSD Unix, 386BSD, was also released in 1992 and led to the NetBSD and FreeBSD projects.

With the 1994 settlement of a lawsuit that UNIX Systems Laboratories brought against the University of California and Berkeley Software Design Inc. (USL v. BSDi), it was clarified that Berkeley had the right to distribute BSD Unix ¿ for free, if it so desired. Since then, BSD Unix has been developed in several different directions, including OpenBSD and DragonFly BSD.

Shortly after UNIX System V Release 4 was produced, AT&T sold all its rights to UNIX to Novell. (Dennis Ritchie likened this to the Biblical story of Esau selling his birthright for the proverbial "mess of pottage".[7]) Novell developed its own version, UnixWare, merging its NetWare with UNIX System V Release 4. Novell tried to use this to battle against Windows NT, but their core markets suffered considerably.

In 1993, Novell decided to transfer the UNIX trademark and certification rights to the X/Open Consortium. In 1996, X/Open merged with OSF, creating the Open Group. Various standards by the Open Group now define what is and what is not a "UNIX" operating system, notably the post-1998 Single UNIX Specification.

Beginning in the late 1980s, an open operating system standardization effort now known as POSIX provided a common baseline for all operating systems; IEEE based POSIX around the common structure of the major competing variants of the Unix system, publishing the first POSIX standard in 1988. In the early 1990s a separate but very similar effort was started by an industry consortium, the Common Open Software Environment (COSE) initiative, which eventually became the Single UNIX Specification administered by The Open Group. Starting in 1998 the Open Group and IEEE started the Austin Group, to provide a common definition of POSIX and the Single UNIX Specification.

In 1983, Richard Stallman announced the GNU project, an ambitious effort to create a free software Unix-like system; "free" in that everyone who received a copy would be free to use, study, modify, and redistribute it. The GNU project's own kernel development project, GNU Hurd, had not produced a working kernel, but in 1992 Linus Torvalds released the Linux kernel as free software under the GNU General Public License. In addition to their use in the Linux operating system, many GNU packages ¿ such as the GNU Compiler Collection (and the rest of the GNU toolchain), the GNU C library and the GNU core utilities ¿ have gone on to play central roles in other free Unix systems as well.

Linux distributions, comprising Linux and large collections of compatible software have become popular both with individual users and in business. Popular distributions include Red Hat Enterprise Linux, Fedora, SUSE Linux Enterprise, openSUSE, Debian GNU/Linux, Ubuntu, Mandriva Linux, Slackware Linux and Gentoo.

1 comment :

  1. Do you have copy writer for so good articles? If so please give me contacts, because this really rocks! :)