The System V Interface Definition (SVID) is a standard that describes the

AT&T AT&T Inc., an abbreviation for its predecessor's former name, the American Telephone and Telegraph Company, is an American multinational telecommunications holding company headquartered at Whitacre Tower in Downtown Dallas, Texas. It is the w ...

UNIX System V behavior, including that of

system call In computing, a system call (syscall) is the programmatic way in which a computer program requests a service from the operating system on which it is executed. This may include hardware-related services (for example, accessing a hard disk drive ...

s, C libraries, available programs and devices. While it was not the first attempt at a standardizations document (the industry trade association /usr/group published a standard in 1984 based on System III with a few system call additions from

BSD The Berkeley Software Distribution (BSD), also known as Berkeley Unix or BSD Unix, is a discontinued Unix operating system developed and distributed by the Computer Systems Research Group (CSRG) at the University of California, Berkeley, beginni ...

), it was an important effort in early standardization of UNIX in a period when UNIX variants were multiplying rapidly and portability was problematic at best. By 1986, AT&T required conformance with SVID issue 2 if vendors were to actually brand their products "System V R3". By the 1990s, however, its importance was largely eclipsed by

POSIX The Portable Operating System Interface (POSIX; ) is a family of standards specified by the IEEE Computer Society for maintaining compatibility between operating systems. POSIX defines application programming interfaces (APIs), along with comm ...

and the

Single UNIX Specification The Single UNIX Specification (SUS) is a standard for computer operating systems, compliance with which is required to qualify for using the "UNIX" trademark. The standard specifies programming interfaces for the C language, a command-line shell, ...

, which were based in part upon the SVID. Part of the reason for this was undoubtedly their vendor-independent approach (see Unix wars).

Versions of SVID

* Version 1, based on System V Release 2, published Spring, 1985 * Version 2, based on System V Release 3, published 1986 (3 volumes) * Version 3, based on System V Release 4, published 1989 * Version 4, updated for compliance with XPG4 and

1003.1-1990, published 1995

References

{{reflist

External links

SVID Fourth Edition
in

PDF Portable document format (PDF), standardized as ISO 32000, is a file format developed by Adobe Inc., Adobe in 1992 to present documents, including text formatting and images, in a manner independent of application software, computer hardware, ...

form
Volume 3

Volume 2

Volume 1b

Volume 1a
Unix standards UNIX System V

Versions of SVID

See also

References

External links