C programming language

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C is a programming language that was designed by Dennis Ritchie during the early 1970s to be used for operating system implementation and other low-level programming tasks.

History

The initial development of C occurred between 1969 and 1973 (according to Ritchie, the most creative period was during 1972). In 1973 it became powerful enough to reimplement the kernel of Unix operating system. In 1978 Brian Kernighan and Dennis Ritchie published the now very well known "C Programming Language" (aka "the white book", K&R) which was effectively the defining work for a good number of years.

C became immensely popular outside Bell Labs after about 1980 and was for a time the dominant language in systems and microcomputer applications programming. It remains so as a systems programming language, and is a staple of the Open Source community.

Bjarne Stroustrup and others at Bell Labs worked in the late 1980s to add object-oriented programming language constructs to C, creating a language called C++ (thus avoiding the issue of whether the successor to "B" and "C" should be "D" or "P"). C++ is now the most common language used for commercial applications on Microsoft Windows systems, though C remains more popular in the Unix world.

Name

It was called "C" because many features derived from an earlier language named B, in commemoration of its parent, BCPL. BCPL was in turn descended from an earlier Algol-derived language, CPL.

Standards

The programming language C has been standardised in the form of an ISO standard. It is standard number ISO 9899. The first ISO edition of this document was published in 1990 (ISO 9899:1990) and was itself a minor modification of a slightly earlier ANSI standard, ANSI X3.159-1989 "Programming Language C". Subsequent editions have been made, some of which have been largely ignored; As of 2001 the most recent edition is ISO 9899:1999, (published in 1999) which was known when it was in draft stage as C9X. K&R C, the version that is described in the first edition of K&R is often considered an unofficial standard of the most basic features a C compiler must have. See also Evolution of C.

"Hello, World!" in C

This very simple application, that prints out "Hello, world!" to the screen. It appeared for the first time in K&R.

#include <stdio.h>
int main(void)
{
    printf("Hello, World!\n");
    return 0;
}

Sources

The Development of the C Language http://cm.bell-labs.com/cm/cs/who/dmr/chist.html


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