Intel Binary Compatibility Standard Explained

The Intel Binary Compatibility Standard (iBCS) is a standardized application binary interface (ABI) for Unix operating systems on Intel-386-compatible computers, published by AT&T, Intel and SCO in 1988, and updated in 1990. It extends source-level standards such as POSIX and XPG3^[1] by standardizing various operating system interfaces, including the filesystem hierarchy layout (i.e., the locations of system files and installed programs),^{[2] [3]} so that Unix programs would run on the various vendor-specific Unix implementations for Intel hardware (such as Xenix, SCO Unix and System V implementations).^[4] The second edition, announced in 1990, added an interface specification for VGA graphics.^[5]

iBCS, edition 2, was supported by various Unix versions, such as UnixWare and third-party implementations. A Linux implementation was developed ca. 1994, enabling Linux to run commercial Unix applications such as WordPerfect.^{[6] [7]}

There have been several security issues in various iBCS implementations over the years.^{[8] [9]}

See also

• Filesystem Hierarchy Standard (FHS)
• Linux Standard Base (LSB)

Notes and References

1. Book: Cameron, Debra . Unix standards . Computer Technology Research Corp. . 1991 . 64.
2. Web site: /opt : Add-on application software packages . . 13 November 2014.
3. Web site: Where to Install My Products on Linux? . . 1 November 2000 . George Kraft IV . 13 November 2014.
4. Noel-Marie . Taylor . Consensys V 4.2 . PC Magazine . 15 June 1993 . 234 .
5. News: Binary Unix 386 Standard to Be Revised . Scott Mace . InfoWorld . 27 August 1990 .
6. Book: Linux—Unleashing the Workstation in Your PC . Stefan . Strobel . Thomas . Uhl . Springer-Verlag . 1994 . 54.
7. News: Eric . Youngdale . 1 September 1994 . Using iBCS2 Under Linux . .
8. Web site: OpenBSD 3.3 Errata .
9. Web site: FreeBSD security advisory: Kernel memory disclosure via ibcs2.