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ANSI C

In 1983, the American National Standards Institute commissioned a committee, X3J11, to standardize the C language. After a long, arduous process, including several widespread public reviews, the committee's work was finally ratified as an American National Standard, X3.159-1989, on December 14, 1989, and published in the spring of 1990. For the most part, ANSI C standardizes existing practice, with a few additions from C++ (most notably function prototypes) and support for multinational character sets (including the much-lambasted trigraph sequences). The ANSI C standard also formalizes the C run-time library support functions.

The published Standard includes a ``Rationale," which explains many of its decisions, and discusses a number of subtle points, including several of those covered here. (The Rationale is ``not part of ANSI Standard X3.159-1989, but is included for information only.")

The Standard has been adopted as an international standard, ISO/IEC 9899:1990, although the Rationale is currently not included.