C

C

a computer programming language combining the advantages of a high-level language with the ability to address the computer at a level comparable with that of an assembly language

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c

(thermodynamics)

calorie

(science and technology)

centi-

(particle physics)

charmed quark

(nucleonics)

curie

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C

(chemistry)

(chemistry)

carbon

(computer science)

A programming language designed to implement the Unix operating system.

(electricity)

capacitance

(electricity)

capacitor

(electricity)

coulomb

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C

1. On drawings, abbr. for course.

2. Abbr. for centigrade or “Celsius.”

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class A, B, C, D, E, F

A classification applied to fire doors, fire windows, roof coverings, interior finishes, places of assembly, etc., to indicate gradations of fire safety. See fire-endurance, fire-door rating.

McGraw-Hill Dictionary of Architecture and Construction. Copyright © 2003 by McGraw-Hill Companies, Inc.

C

(language)

A programming language designed by Dennis Ritchie at AT&T Bell Labs ca. 1972 for systems programming on the PDP-11 and immediately used to reimplement Unix.

It was called "C" because many features derived from an earlier compiler named "B". In fact, C was briefly named "NB". B was itself strongly influenced by BCPL. Before Bjarne Stroustrup settled the question by designing C++, there was a humorous debate over whether C's successor should be named "D" or "P" (following B and C in "BCPL").

C is terse, low-level and permissive. It has a macro preprocessor, cpp.

Partly due to its distribution with Unix, C became immensely popular outside Bell Labs after about 1980 and is now the dominant language in systems and microcomputer applications programming. It has grown popular due to its simplicity, efficiency, and flexibility. C programs are often easily adapted to new environments.

C is often described, with a mixture of fondness and disdain, as "a language that combines all the elegance and power of assembly language with all the readability and maintainability of assembly language".

Ritchie's original C, known as K&R C after Kernighan and Ritchie's book, has been standardised (and simultaneously modified) as ANSI C.

See also ACCU, ae, c68, c386, C-Interp, cxref, dbx, dsp56k-gcc, dsp56165-gcc, gc, GCT, GNU C, GNU superoptimiser, Harvest C, malloc, mpl, Pthreads, ups.

This article is provided by FOLDOC - Free Online Dictionary of Computing (foldoc.org)

C

(1) See coulomb.

(2) A high-level programming language developed at Bell Labs that is also able to manipulate the computer at a low level like assembly language. Developed in the 1970s, by the end of the 1980s, C became the language of choice for developing commercial software. There are C/C++ compilers for all major platforms. C, and its object-oriented successor C++, are used to write a huge variety of applications and many operating systems. In 1989, C was standardized by ANSI (X3J11 committee) and ISO.

C++ (C Plus Plus)
Created by Bjarne Stroustrup in 1983, C++ added object-oriented programming (OOP) to C. Originally called "C with Classes," C++ became the standard C language, often designated as C/C++. In contrast, Smalltalk and other object-oriented languages did not provide the familiar structures of conventional languages such as C and Pascal. See object-oriented programming, Smalltalk, Visual C++, Objective-C, C# and Managed C++.

Nothing But Functions
C and C++ are written as a series of functions that call each other for processing. Even the body of the program is a function named "main." Functions are very flexible, allowing programmers to choose from the standard library or write their own, which they do in every program. They can also use third-party libraries for specific purposes. See function.

Its Origin
C was developed to allow Unix to run on a variety of computers. After Bell Labs' Ken Thompson and Dennis Ritchie created Unix and got it running on several PDP computers, they wanted a way to easily port it to other machines without having to rewrite it from scratch. Thompson created the B language, which was a simpler version of the BCPL language, itself a version of CPL. Later, in order to improve B, Thompson and Ritchie created C.

The following examples convert Fahrenheit to centigrade in C and C++. For another example of C code, see event loop.

 In C

 main()   {
  float fahr;
  printf("Enter Fahrenheit: ");
  scanf("%f", &fahr);
  printf("Celsius is %f\n", (fahr-32)*5/9);
          }


 In C++

 void main() {
  float fahr;
  cout << "Enter Fahrenheit: "; 
  cin >> fahr;
  fahr = (((fahr-32)*5)/9);
  cout << "Celsius = " << fahr << endl;
  return 0;
             }

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