System V

Unix System V, commonly abbreviated SysV and rarely called System 5, was one of the versions of the Unix operating system. It was originally developed by AT&T and first released in 1983. Four major versions of System V were released, termed Releases 1, 2, 3 and 4. System V Release 4, or SVR4, was the most successful version, and the source of several common Unix features, such as "SysV init scripts" (/etc/init.d), used to control system startup and shutdown. The system also forms the basis of the System V Interface Definition (SVID), a standard defining how System V systems should work. The other one of the two major branches of the Unix system is Berkeley Software Distribution.
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1. The other major versions of the Unix operating system apart from BSD. Developed by AT&T. Later versions of Unix such as SunOS combined the best features of System V and BSD Unix.
(1994-10-31)
[Differences?]
2. A supplier of Unix open systems for Intel x86 processors. They supply products from SCO and Solaris and offer general support for Unix, TCP/IP, and Internet. They serve and create third-party WWW pages and provide on-line support for commercial and non-commercial applications.
http://www.systemv.com/.
See also System V Interface Definition.
(1994-12-12)

System V