Version 7 Unix
Encyclopedia
Seventh Edition Unix, also called Version 7 Unix, Version 7 or just V7, was an important early release of the Unix
operating system
. V7, released in 1979, was the last Bell Laboratories release to see widespread distribution before the commercialization of Unix by AT&T
in the early 1980s. V7 was originally developed for Digital Equipment Corporation
's PDP-11
minicomputers and was later ported to other platforms.
Unix versions from Bell Labs were designated by the edition of the user's manual with which they were accompanied. The Seventh Edition was preceded by Sixth Edition
, which was the first version to be widely distributed outside of the Labs. Development of the Research Unix
line continued with the Eighth Edition
, which incorporated development from 4.1BSD
, through the Tenth Edition, after which the Bell Labs researchers concentrated on developing Plan 9
.
V7 was the first readily portable
version of Unix. As this was the era of minicomputers, with their many architectural variations, and also the dawning of the market for 16-bit microprocessors, many ports were completed within the first few years of its release. The first Sun
workstations (then based on the Motorola 68010
) ran a V7 port by UniSoft
; the first version of Xenix
for the Intel 8086
was derived from V7; and Onyx Systems
soon produced a Zilog
Z8000 computer running V7. The VAX
port of V7, called UNIX/32V
, was the direct ancestor of the popular 4BSD family
of Unix systems. The group at University of Wollongong
that had ported V6
to the Interdata 7/32 ported V7 to that machine as well, which was sold commercially under the name Edition VII by Interdata and Perkin-Elmer (now known as PerkinElmer
) on most models of the 3200 series, the first commercial UNIX offering.
DEC
distributed their own PDP-11 version of V7, called V7M (for modified). V7M, developed by DEC's original Unix Engineering Group (UEG), contained many enhancements to the kernel for the PDP-11 line of computers including significantly improved hardware error recovery and many additional device drivers. UEG evolved into the group that later developed Ultrix
.
Due to its power yet elegant simplicity, many old-time Unix users fondly (and with a good amount of nostalgia) remember V7 as the pinnacle of Unix development and have dubbed it "the last true Unix," an improvement over all preceding and following Unices.
license.
Bootable images for V7 can still be downloaded today, and can be run on modern hosts using PDP-11 emulators such as SIMH
.
These first appeared in the Research Unix lineage in Version 7, although early versions of some of them had already been picked up by PWB/UNIX.
The combination of the Bourne shell and the hashbang convention meant that scripts and scripting languages could provide the same user experience as native C programs.
Unix
Unix is a multitasking, multi-user computer operating system originally developed in 1969 by a group of AT&T employees at Bell Labs, including Ken Thompson, Dennis Ritchie, Brian Kernighan, Douglas McIlroy, and Joe Ossanna...
operating system
Operating system
An operating system is a set of programs that manage computer hardware resources and provide common services for application software. The operating system is the most important type of system software in a computer system...
. V7, released in 1979, was the last Bell Laboratories release to see widespread distribution before the commercialization of Unix by AT&T
AT&T
AT&T Inc. is an American multinational telecommunications corporation headquartered in Whitacre Tower, Dallas, Texas, United States. It is the largest provider of mobile telephony and fixed telephony in the United States, and is also a provider of broadband and subscription television services...
in the early 1980s. V7 was originally developed for Digital Equipment Corporation
Digital Equipment Corporation
Digital Equipment Corporation was a major American company in the computer industry and a leading vendor of computer systems, software and peripherals from the 1960s to the 1990s...
's PDP-11
PDP-11
The PDP-11 was a series of 16-bit minicomputers sold by Digital Equipment Corporation from 1970 into the 1990s, one of a succession of products in the PDP series. The PDP-11 replaced the PDP-8 in many real-time applications, although both product lines lived in parallel for more than 10 years...
minicomputers and was later ported to other platforms.
Unix versions from Bell Labs were designated by the edition of the user's manual with which they were accompanied. The Seventh Edition was preceded by Sixth Edition
Version 6 Unix
Sixth Edition Unix, also called Version 6 Unix or just V6, was the first version of the Unix operating system to see wide release outside Bell Labs. It was released in May 1975 and, like its direct predecessor, targeted the DEC PDP-11 family of minicomputers...
, which was the first version to be widely distributed outside of the Labs. Development of the Research Unix
Research Unix
Research Unix is a term used to refer to versions of the Unix operating system for DEC PDP-7, PDP-11, VAX and Interdata 7/32 and 8/32 computers, developed in the Bell Labs Computing Science Research Center ....
line continued with the Eighth Edition
Version 8 Unix
Eighth Edition Unix, also known as Version 8 Unix or V8, was a version of the Research Unix operating system developed and used internally at Bell Labs and a select number of universities. It was "released" in February 1985, ran on VAX hardware, and was a variant of 4.1cBSD with some System V.1 ...
, which incorporated development from 4.1BSD
Berkeley Software Distribution
Berkeley Software Distribution is a Unix operating system derivative developed and distributed by the Computer Systems Research Group of the University of California, Berkeley, from 1977 to 1995...
, through the Tenth Edition, after which the Bell Labs researchers concentrated on developing Plan 9
Plan 9 from Bell Labs
Plan 9 from Bell Labs is a distributed operating system. It was developed primarily for research purposes as the successor to Unix by the Computing Sciences Research Center at Bell Labs between the mid-1980s and 2002...
.
V7 was the first readily portable
Porting
In computer science, porting is the process of adapting software so that an executable program can be created for a computing environment that is different from the one for which it was originally designed...
version of Unix. As this was the era of minicomputers, with their many architectural variations, and also the dawning of the market for 16-bit microprocessors, many ports were completed within the first few years of its release. The first Sun
Sun Microsystems
Sun Microsystems, Inc. was a company that sold :computers, computer components, :computer software, and :information technology services. Sun was founded on February 24, 1982...
workstations (then based on the Motorola 68010
Motorola 68010
The Motorola MC68010 processor is a 16/32-bit microprocessor from Motorola, released in 1982. In line with the Motorola 68000 naming convention, it is usually just referred to as the 010 ....
) ran a V7 port by UniSoft
UniSoft
UniSoft Corporation is a former Unix vendor that now works on software for digital television development and broadcast.- History :UniSoft was founded in 1981, initially working as a Unix porting house, completing over 225 Unix ports to numerous CPU architectures. Its port of Version 7 Unix was the...
; the first version of Xenix
Xenix
Xenix is a version of the Unix operating system, licensed to Microsoft from AT&T in the late 1970s. The Santa Cruz Operation later acquired exclusive rights to the software, and eventually superseded it with SCO UNIX ....
for the Intel 8086
Intel 8086
The 8086 is a 16-bit microprocessor chip designed by Intel between early 1976 and mid-1978, when it was released. The 8086 gave rise to the x86 architecture of Intel's future processors...
was derived from V7; and Onyx Systems
Onyx Systems
Onyx Systems, Inc., founded in Cupertino, California in 1979 by Bob Marsh and Kip Myers, was one of the earliest vendors of microprocessor-based Unix systems...
soon produced a Zilog
Zilog
Zilog, Inc., previously known as ZiLOG , is a manufacturer of 8-bit and 24-bit microcontrollers, and is most famous for its Intel 8080-compatible Z80 series.-History:...
Z8000 computer running V7. The VAX
VAX
VAX was an instruction set architecture developed by Digital Equipment Corporation in the mid-1970s. A 32-bit complex instruction set computer ISA, it was designed to extend or replace DEC's various Programmed Data Processor ISAs...
port of V7, called UNIX/32V
UNIX/32V
UNIX/32V was an early version of the Unix operating system from Bell Laboratories, released in June 1979. 32V was a direct port of the PDP-11 Seventh Edition Unix to the DEC VAX architecture....
, was the direct ancestor of the popular 4BSD family
Berkeley Software Distribution
Berkeley Software Distribution is a Unix operating system derivative developed and distributed by the Computer Systems Research Group of the University of California, Berkeley, from 1977 to 1995...
of Unix systems. The group at University of Wollongong
University of Wollongong
The University of Wollongong is a public university located in the coastal city of Wollongong, New South Wales, Australia, approximately 80 kilometres south of Sydney...
that had ported V6
Wollongong Unix
A port of Version 6 Unix to the Interdata 7/32 was completed by Richard Miller and Ross Nealon at Wollongong University, Australia, during 1976-1977. This project was supervised by professor Juris Reinfelds. The resulting system was called Wollongong Interdata UNIX, Level 6...
to the Interdata 7/32 ported V7 to that machine as well, which was sold commercially under the name Edition VII by Interdata and Perkin-Elmer (now known as PerkinElmer
PerkinElmer
PerkinElmer, Inc. is an American multinational technology corporation, focused in the business areas of human and environmental health, including environmental analysis, food and consumer product safety, medical imaging, drug discovery, diagnostics, biotechnology, industrial applications, and life...
) on most models of the 3200 series, the first commercial UNIX offering.
DEC
Digital Equipment Corporation
Digital Equipment Corporation was a major American company in the computer industry and a leading vendor of computer systems, software and peripherals from the 1960s to the 1990s...
distributed their own PDP-11 version of V7, called V7M (for modified). V7M, developed by DEC's original Unix Engineering Group (UEG), contained many enhancements to the kernel for the PDP-11 line of computers including significantly improved hardware error recovery and many additional device drivers. UEG evolved into the group that later developed Ultrix
Ultrix
Ultrix was the brand name of Digital Equipment Corporation's native Unix systems. While ultrix is the Latin word for avenger, the name was chosen solely for its sound.-History:...
.
Due to its power yet elegant simplicity, many old-time Unix users fondly (and with a good amount of nostalgia) remember V7 as the pinnacle of Unix development and have dubbed it "the last true Unix," an improvement over all preceding and following Unices.
Released as free software
In 2002, Caldera International released V7 under a free softwareFree software
Free software, software libre or libre software is software that can be used, studied, and modified without restriction, and which can be copied and redistributed in modified or unmodified form either without restriction, or with restrictions that only ensure that further recipients can also do...
license.
Bootable images for V7 can still be downloaded today, and can be run on modern hosts using PDP-11 emulators such as SIMH
SIMH
SIMH is a highly portable, multi-system emulator which runs on Windows, Linux, Mac OS X, FreeBSD, OpenBSD, NetBSD, OpenVMS, and other operating systems...
.
V7/x86
An x86 port is under active development by Nordier & Associates. The current version is 0.8a. The project has produced a bootable CD image with an installer script.New features in Version 7
Many new features were introduced in Version 7.- Programming tools: lexLex programming toolLex is a computer program that generates lexical analyzers . Lex is commonly used with the yacc parser generator. Lex, originally written by Mike Lesk and Eric Schmidt, is the standard lexical analyzer generator on many Unix systems, and a tool exhibiting its behavior is specified as part of the...
, yaccYaccThe computer program yacc is a parser generator developed by Stephen C. Johnson at AT&T for the Unix operating system. The name is an acronym for "Yet Another Compiler Compiler." It generates a parser based on an analytic grammar written in a notation similar to BNF.Yacc used to be available as...
, lint, pccPortable C CompilerThe Portable C Compiler is an early compiler for the C programming language written by Stephen C...
, and make.
These first appeared in the Research Unix lineage in Version 7, although early versions of some of them had already been picked up by PWB/UNIX.
- New commands: the Bourne shellBourne shellThe Bourne shell, or sh, was the default Unix shell of Unix Version 7 and most Unix-like systems continue to have /bin/sh - which will be the Bourne shell, or a symbolic link or hard link to a compatible shell - even when more modern shells are used by most users.Developed by Stephen Bourne at AT&T...
, at, awk, calendar, f77, fortune, tarTar (file format)In computing, tar is both a file format and the name of a program used to handle such files...
(replacing the tp command), touch, uucpUUCPUUCP is an abbreviation for Unix-to-Unix Copy. The term generally refers to a suite of computer programs and protocols allowing remote execution of commands and transfer of files, email and netnews between computers. Specifically, a command named uucp is one of the programs in the suite; it... - New system callSystem callIn computing, a system call is how a program requests a service from an operating system's kernel. This may include hardware related services , creating and executing new processes, and communicating with integral kernel services...
s: access, acct, alarm, chrootChrootA chroot on Unix operating systems is an operation that changes the apparent root directory for the current running process and its children. A program that is run in such a modified environment cannot name files outside the designated directory tree. The term "chroot" may refer to the chroot...
(originally used to test the v7 distribution during preparation), ioctlIoctlIn computing, ioctl, short for input/output control, is a system call for device-specific operations and other operations which cannot be expressed by regular system calls. It takes a parameter specifying a request code; the effect of a call depends completely on the request code. Request codes are...
, lseek (previously only 24-bit offsets were available), umaskUmaskumask is a command and a function in POSIX environments that sets the file mode creation mask of the current process which limits the permission modes for files and directories created by the process...
, utime - New library calls: The new stdio routines, mallocMallocC dynamic memory allocation refers to performing dynamic memory allocation in the C via a group of functions in the C standard library, namely malloc, realloc, calloc and free....
, getenv, popen/system - Environment variables
- The #! convention
The combination of the Bourne shell and the hashbang convention meant that scripts and scripting languages could provide the same user experience as native C programs.