ANSI C is the standard published by the American National Standards Institute (ANSI) for the C programming language. Software developers writing in C are encouraged to conform to the requirements in the document, as it encourages easily portable code.
History of ANSI C and ISO C
The first standard for C was published by ANSI. Although this document was subsequently adopted by International Organization for Standardization (ISO) and subsequent revisions published by ISO have been adopted by ANSI, the name ANSI C (rather than ISO C) is still more widely used. While some software developers use the term ISO C, others are standards body–neutral and use Standard C.
C89
In 1983, the American National Standards Institute formed a committee, X3J11, to establish a standard specification of C. After a long and arduous process, the standard was completed in 1989 and ratified as ANSI X3.159-1989 "Programming Language C." This version of the language is often referred to as "ANSI C", or sometimes "C89" (to distinguish it from C99).
C90
In 1990, the ANSI C standard (with a few minor modifications) was adopted by the International Organization for Standardization as ISO/IEC 9899:1990. This version is sometimes called C90. Therefore, the terms "C89" and "C90" refer to essentially the same language.
C99
In March 2000, ANSI adopted the ISO/IEC 9899:1999 standard. This standard is commonly referred to as C99, and it is the current standard for C programming language.
upport from major compilers
ANSI C is now supported by almost all the widely used compilers. Most of the C code being written nowadays is based on ANSI C. Any program written "only" in standard C and without any hardware dependent assumptions is virtually guaranteed to compile correctly on any platform with a conforming C implementation. Without such precautions, most programs may compile only on a certain platform or with a particular compiler, due, for example, to the use of non-standard libraries, such as GUI libraries, or to the reliance on compiler- or platform-specific attributes such as the exact size of certain data types and byte endianness.
Compliance detectability
To mitigate the differences between K&R C and the ANSI C standard, the __STDC__ macro can be used to split code into ANSI and K&R sections. #if __STDC__ extern int getopt(int, char * const *, const char *); #else extern int getopt(); #endif
Some suggest using "#if __STDC__" as above rather than "#ifdef __STDC__" because some compilers set __STDC__ to zero to indicate non-ANSI compliance.
External links
* [http://www.open-std.org/jtc1/sc22/wg14/ ISO C working group]
ANSI C — es un estándar publicado por el Instituto Nacional Estadounidense de Estándares (ANSI), para el lenguaje de programación C. Se recomienda a los desarrolladores de software en C que cumplan con los requisitos descritos en el documento para… … Wikipedia Español
ANSI C — стандарт языка C, опубликованный Американским национальным институтом стандартов (ANSI). Следование этому стандарту помогает создавать легко портируемые программы. Содержание 1 История 1.1 C89 1.2 C90 … Википедия
ANSI — 〈Abk. für engl.〉 American National Standards Institute (nationales amerikanisches Standardisierungsinstitut) * * * ANSI [Abk. für American National Standards Institute, »amerikanisches Institut für nationale Normung«], das 1918 gegründete… … Universal-Lexikon
ANSI — koduotė statusas T sritis informatika apibrėžtis Aštuonių bitų ↑koduotė, turinti JAV standarto statusą, sutampanti su Vakarų Europos šalyse vartojamo tarptautinio standarto ISO/IEC 8859 1 koduote. Pavadinta JAV nacionalinio standartų instituto… … Enciklopedinis kompiuterijos žodynas
ANSI — [ˈænsi] noun ORGANIZATIONS MANUFACTURING American National Standards Institute; an organization that fixes rules on the design, quality, and safety of products: • The machines aren t meant for indoor use, and ANSI calls for a warning to be put in … Financial and business terms
ANSI — ansí (del lat. «aeque sic» o «ad sic»; pop.) adv. Así. * * * ansí. (Del lat. aeque sic, o ad sic). adv. m. desus. así. U. c. rur. * * * El Instituto Nacional Estadounidense de Estándares (ANSI, por sus siglas en inglés: American National… … Enciclopedia Universal
ANSI X.12 — ANSI ASC X12 steht für American National Standards Institute Accredited Standards Committee X12 und ist ein Datenübertragungsstandard im EDI Bereich, der hauptsächlich in USA verwendet wird. Die Gruppe wurde 1979 gegründet und verabschiedete 1982 … Deutsch Wikipedia
ANSI — American National Standards Institute an organization in the US which sets the standards used for testing the quality and safety of electronic equipment, scientific equipment etc. It has also established a standard set of letters and numbers… … Dictionary of contemporary English
ANSI — Abreviatura de la American National Standards Institute. Diccionario Mosby Medicina, Enfermería y Ciencias de la Salud, Ediciones Hancourt, S.A. 1999 … Diccionario médico
ANSI C — ANSI Standard für C, besonderes Merkmal ist die Typangabe in der Parameterliste der Prozeduren und strengerer Typcheck … Acronyms
