Unix Workstation Support Group
Indiana University
http://www.uwsg.iu.edu/
These are notes to be used in conjunction with the "Unix for Advanced Users" course offered by the Unix Workstation Support Group at Indiana University. If you are interested in taking this class, please visit our registration page.
Introduction
Unix today is a mature operating system, and is used heavily in a large variety of scientific, engineering, and mission critical applications. Interest in Unix has grown substantially in recent years because of the proliferation of the Linux (a Unix look-alike) operating system. This section briefly describes the history of Unix, why it is considered a good operating environment, and the marriage between Unix and C.
History of Unix
The Unix operating system found its beginnings in MULTICS ( Multiplexed Operating and Computing System). The MULTICS project began in the mid 1960s as a joint effort by General Electric, Massachusetts Institute for Technology and Bell Laboratories. In 1969 Bell Laboratories pulled out of the project.
The Unix operating system found its beginnings in MULTICS ( Multiplexed Operating and Computing System). The MULTICS project began in the mid 1960s as a joint effort by General Electric, Massachusetts Institute for Technology and Bell Laboratories. In 1969 Bell Laboratories pulled out of the project.
One of Bell Laboratories people involved in the project was Ken Thompson. He liked the potential MULTICS had, but felt it was too complex and that the same thing could be done in simpler way. In 1969 he wrote the first version of Unix, called UNICS. UNICS stood for Uniplexed Operating and Computing System. Although the operating system has changed, the name stuck and was eventually shortened to Unix.
Ken Thompson teamed up with Dennis Ritchie, who wrote the first C compiler. In 1973 they rewrote the Unix kernel in C. The following year a version of Unix known as the Fifth Edition was first licensed to universities. The Seventh Edition, released in 1978, served as a dividing point for two divergent lines of Unix development. These two branches are known as SVR4 (System V) and BSD.
Ken Thompson spent a year's sabbatical with the University of California at Berkeley. While there he and two graduate students, Bill Joy and Chuck Haley, wrote the first Berkely version of Unix, which was distributed to students. This resulted in the source code being worked on and developed by many different people. The Berkeley version of Unix is known as BSD, Berkeley Software Distribution. From BSD came the vi editor, C shell, virtual memory, Sendmail, and support for TCP/IP.
For several years SVR4 was the more conservative, commercial, and well supported. Today SVR4 and BSD look very much alike. Probably the biggest cosmetic difference between them is the way the ps command functions.
The Linux operating system was developed as a Unix look alike and borrows from both BSD and SVR4.