C (programming language)

C
The C Programming Language¹ (aka "K&R") is the seminal book on C.
Paradigm	Imperative (procedural), structured
Appeared in	1972
Designed by	Dennis Ritchie
Developer	Originally: Dennis Ritchie & Bell Labs ANSI C: ANSI X3J11 ISO C: ISO/IEC JTC1/SC22/WG14
Stable release	C99 (March 2000)
Preview release	C1X
Typing discipline	Static, weak, manifest
Major implementations	Clang, GCC, MSVC, Turbo C, Watcom C
Dialects	Cyclone, Unified Parallel C, Split-C, Cilk, C*
Influenced by	B (BCPL, CPL), ALGOL 68,² Assembly, PL/I, FORTRAN
Influenced	Numerous: AWK, csh, C++, C-- , C#, Objective-C, BitC, D, Go, Java, JavaScript, Limbo, LPC, Perl, PHP, Pike, Processing, Python
OS	Cross-platform (multi-platform)
Usual file extensions	.h .c
C Programming at Wikibooks

This article includes a list of references, but its sources remain unclear because it has insufficient inline citations. Please help to improve this article by introducing more precise citations where appropriate. (May 2010)

C (pronounced /ˈsiː/ see) is a general-purpose computer programming language developed in 1972 by Dennis Ritchie at the Bell Telephone Laboratories for use with the Unix operating system.³

Although C was designed for implementing system software,⁴ it is also widely used for developing portable application software.

C is one of the most popular programming languages of all time⁵⁶ and there are very few computer architectures for which a C compiler does not exist. C has greatly influenced many other popular programming languages, most notably C++, which began as an extension to C.

Design

C is an imperative (procedural) systems implementation language. It was designed to be compiled using a relatively straightforward compiler, to provide low-level access to memory, to provide language constructs that map efficiently to machine instructions, and to require minimal run-time support. C was therefore useful for many applications that had formerly been coded in assembly language.

Despite its low-level capabilities, the language was designed to encourage cross-platform programming. A standards-compliant and portably written C program can be compiled for a very wide variety of computer platforms and operating systems with little or no change to its source code. The language has become available on a very wide range of platforms, from embedded microcontrollers to supercomputers.

Minimalism

C's design is tied to its intended use as a portable systems implementation language. It provides simple, direct access to any addressable object (for example, memory-mapped device control registers), and its source-code expressions can be translated in a straightforward manner to primitive machine operations in the executable code. Some early C compilers were comfortably implemented (as a few distinct passes communicating via intermediate files) on PDP-11 processors having only 16 address bits; however, C99 assumes a 512 KB minimum compilation platform. Target platforms for C programs range from 8-bit microcontrollers to supercomputers.

Characteristics

Like most imperative languages in the ALGOL tradition, C has facilities for structured programming and allows lexical variable scope and recursion, while a static type system prevents many unintended operations. In C, all executable code is contained within functions. Function parameters are always passed by value. Pass-by-reference is simulated in C by explicitly passing pointer values. Heterogeneous aggregate data types (struct) allow related data elements to be combined and manipulated as a unit. C program source text is free-format, using the semicolon as a statement terminator.

C also exhibits the following more specific characteristics:

Variables may be hidden in nested blocks
Partially weak typing; for instance, characters can be used as integers
Low-level access to computer memory by converting machine addresses to typed pointers
Function and data pointers supporting ad hoc run-time polymorphism
array indexing as a secondary notion, defined in terms of pointer arithmetic
A preprocessor for macro definition, source code file inclusion, and conditional compilation
Complex functionality such as I/O, string manipulation, and mathematical functions consistently delegated to library routines
A relatively small set of reserved keywords
A large number of compound operators, such as +=, -=, *=, ++ etc.

C's lexical structure resembles B more than ALGOL. For example:

{ ... } rather than begin ... end
= is used for assignment (copying), like Fortran, rather than ALGOL's :=
== is used to test for equality (rather than .EQ. in Fortran, or = in BASIC and ALGOL)
Logical "and" and "or" are represented with && and ||, which don't evaluate the right operand if the result can be determined from the left alone (short-circuit evaluation), and are semantically distinct from the bit-wise operators & and |

Absent features

The relatively low-level nature of the language affords the programmer close control over what the computer does, and allows special tailoring and aggressive optimization for a particular platform. This allows the code to run efficiently on very limited hardware, such as embedded systems, and keeps the language definition small enough to allow the programmer to understand the entire language, but at the cost of some features not being included that are available in other languages:

No nested function definitions
No direct assignment of arrays or strings (copying can be done via standard functions; assignment of objects having struct or union type is supported)
No automatic garbage collection
No requirement for bounds checking of arrays
No operations on whole arrays at the language level
No syntax for ranges, such as the A..B notation used in several languages
Prior to C99, no separate Boolean type (1 (true) and 0 (false) are used instead)⁷
No formal closures or functions as parameters (only function pointers)
No generators or coroutines; intra-thread control flow consists of nested function calls, except for the use of the longjmp library function
No built-in exception handling; standard library functions signify error conditions with the global errno variable and/or special return values
Only rudimentary support for modular programming
No compile-time polymorphism in the form of function or operator overloading
Very limited support for object-oriented programming with regard to polymorphism and inheritance
Limited support for encapsulation
No native support for multithreading and networking
No standard libraries for computer graphics and several other application programming needs

A number of these features are available as extensions in some compilers, or are provided in some operating environments (e.g., POSIX), or are supplied by third-party libraries, or can be simulated by adopting certain coding disciplines.

Undefined behavior

Many operations in C that have undefined behavior are not required to be diagnosed at compile time. In the case of C, "undefined behavior" means that the exact behavior which arises is not specified by the standard, and exactly what will happen does not have to be documented by the C implementation. A famous and humorous expression in the newsgroups comp.std.c and comp.lang.c is that the program could cause "demons to fly out of your nose".⁸ Sometimes in practice what happens for an instance of undefined behavior is a bug that is hard to track down and which may corrupt the contents of memory. Sometimes a particular compiler generates reasonable and well-behaved actions that are completely different from those that would be obtained using a different C compiler. The reason some behavior has been left undefined is to allow compilers for a wide variety of instruction set architectures to generate more efficient executable code for well-defined behavior, which was deemed important for C's primary role as a systems implementation language; thus C makes it the programmer's responsibility to avoid undefined behavior, possibly using tools to find parts of a program whose behavior is undefined. Examples of undefined behavior are:

accessing outside the bounds of an array
overflowing a signed integer
reaching the end of a non-void function without finding a return statement, when the return value is used
reading the value of a variable before initializing it

These operations are all programming errors that could occur using many programming languages; C draws criticism because its standard explicitly identifies numerous cases of undefined behavior, including some where the behavior could have been made well defined, and does not specify any run-time error handling mechanism.

Invoking fflush() on a stream opened for input is an example of a different kind of undefined behavior, not necessarily a programming error but a case for which some conforming implementations may provide well-defined, useful semantics (in this example, presumably discarding input through the next new-line) as an allowed extension. Over-reliance on nonstandard extensions undermines software portability.

History

Early developments

The initial development of C occurred at AT&T Bell Labs between 1969 and 1973;² according to Ritchie, the most creative period occurred in 1972. It was named "C" because its features were derived from an earlier language called "B", which according to Ken Thompson was a stripped-down version of the BCPL programming language.

The origin of C is closely tied to the development of the Unix operating system, originally implemented in assembly language on a PDP-7 by Ritchie and Thompson, incorporating several ideas from colleagues. Eventually they decided to port the operating system to a PDP-11. B's inability to take advantage of some of the PDP-11's features, notably byte addressability, led to the development of an early version of C.

The original PDP-11 version of the Unix system was developed in assembly language. By 1973, with the addition of struct types, the C language had become powerful enough that most of the Unix kernel was rewritten in C. This was one of the first operating system kernels implemented in a language other than assembly. (Earlier instances include the Multics system (written in PL/I), and MCP (Master Control Program) for the Burroughs B5000 written in ALGOL in 1961.)

K&R C

In 1978, Brian Kernighan and Dennis Ritchie published the first edition of The C Programming Language.⁹ This book, known to C programmers as "K&R", served for many years as an informal specification of the language. The version of C that it describes is commonly referred to as K&R C. The second edition of the book¹ covers the later ANSI C standard.

K&R introduced several language features:

standard I/O library
long int data type
unsigned int data type
compound assignment operators of the form =op (such as =-) were changed to the form op= to remove the semantic ambiguity created by such constructs as i=-10, which had been interpreted as i =- 10 instead of the possibly intended i = -10

Even after the publication of the 1989 C standard, for many years K&R C was still considered the "lowest common denominator" to which C programmers restricted themselves when maximum portability was desired, since many older compilers were still in use, and because carefully written K&R C code can be legal Standard C as well.

In early versions of C, only functions that returned a non-int value needed to be declared if used before the function definition; a function used without any previous declaration was assumed to return type int, if its value was used.

For example:

long int SomeFunction();
/* int OtherFunction(); */
 
/* int */ CallingFunction()
{
    long int test1;
    register /* int */ test2;
 
    test1 = SomeFunction();
    if (test1 > 0)
          test2 = 0;
    else
          test2 = OtherFunction();
 
    return test2;
}

All the above commented-out int declarations could be omitted in K&R C.

Since K&R function declarations did not include any information about function arguments, function parameter type checks were not performed, although some compilers would issue a warning message if a local function was called with the wrong number of arguments, or if multiple calls to an external function used different numbers or types of arguments. Separate tools such as Unix's lint utility were developed that (among other things) could check for consistency of function use across multiple source files.

In the years following the publication of K&R C, several unofficial features were added to the language, supported by compilers from AT&T and some other vendors. These included:

void functions
functions returning struct or union types (rather than pointers)
assignment for struct data types
enumerated types

The large number of extensions and lack of agreement on a standard library, together with the language popularity and the fact that not even the Unix compilers precisely implemented the K&R specification, led to the necessity of standardization.

ANSI C and ISO C

Main article: ANSI C

During the late 1970s and 1980s, versions of C were implemented for a wide variety of mainframe computers, minicomputers, and microcomputers, including the IBM PC, as its popularity began to increase significantly.

In 1983, the American National Standards Institute (ANSI) formed a committee, X3J11, to establish a standard specification of C. In 1989, the standard was ratified as ANSI X3.159-1989 "Programming Language C". This version of the language is often referred to as ANSI C, Standard C, or sometimes C89.

In 1990, the ANSI C standard (with formatting changes) was adopted by the International Organization for Standardization (ISO) as ISO/IEC 9899:1990, which is sometimes called C90. Therefore, the terms "C89" and "C90" refer to the same programming language.

ANSI, like other national standards bodies, no longer develops the C standard independently, but defers to the ISO C standard. National adoption of updates to the international standard typically occurs within a year of ISO publication.

One of the aims of the C standardization process was to produce a superset of K&R C, incorporating many of the unofficial features subsequently introduced. The standards committee also included several additional features such as function prototypes (borrowed from C++), void pointers, support for international character sets and locales, and preprocessor enhancements. The syntax for parameter declarations was also augmented to include the style used in C++, although the K&R interface continued to be permitted, for compatibility with existing source code.

C89 is supported by current C compilers, and most C code being written nowadays is based on it. Any program written only in Standard C and without any hardware-dependent assumptions will run correctly on any platform with a conforming C implementation, within its resource limits. Without such precautions, 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 a reliance on compiler- or platform-specific attributes such as the exact size of data types and byte endianness.

In cases where code must be compilable by either standard-conforming or K&R C-based compilers, the __STDC__ macro can be used to split the code into Standard and K&R sections to prevent using on a K&R C-based compiler features available only in Standard C.

C99

Main article: C99

After the ANSI/ISO standardization process, the C language specification remained relatively static for some time. In 1995 Normative Amendment 1 to the 1990 C standard was published, to correct some details and to add more extensive support for international character sets. The C standard was further revised in the late 1990s, leading to the publication of ISO/IEC 9899:1999 in 1999, which is commonly referred to as "C99". It has since been amended three times by Technical Corrigenda. The international C standard is maintained by the working group ISO/IEC JTC1/SC22/WG14.

C99 introduced several new features, including inline functions, several new data types (including long long int and a complex type to represent complex numbers), variable-length arrays, support for variadic macros (macros of variable arity) and support for one-line comments beginning with //, as in BCPL or C++. Many of these had already been implemented as extensions in several C compilers.

C99 is for the most part backward compatible with C90, but is stricter in some ways; in particular, a declaration that lacks a type specifier no longer has int implicitly assumed. A standard macro __STDC_VERSION__ is defined with value 199901L to indicate that C99 support is available. GCC, Sun Studio and other C compilers now support many or all of the new features of C99.

C1X

Main article: C1X

In 2007, work began in anticipation of another revision of the C standard, informally called "C1X". The C standards committee has adopted guidelines to limit the adoption of new features that have not been tested by existing implementations.

Uses

C is often used for "system programming", including implementing operating systems and embedded system applications, due to a combination of desirable characteristics such as code portability and efficiency, ability to access specific hardware addresses, ability to pun types to match externally imposed data access requirements, and low runtime demand on system resources. C can also be used for website programming using CGI as a "gateway" for information between the Web application, the server, and the browser.¹⁰ Some reasons for choosing C over interpreted languages are its speed, stability, and near-universal availability.¹¹

One consequence of C's wide acceptance and efficiency is that compilers, libraries, and interpreters of other programming languages are often implemented in C. The primary implementations of Python (CPython), Perl 5, and PHP are all written in C.

Due to its thin layer of abstraction and low overhead, C allows efficient implementations of algorithms and data structures, which is useful for programs that perform a lot of computations. For example, the GNU Multi-Precision Library, the GNU Scientific Library, Mathematica and MATLAB are completely or partially written in C.

C is sometimes used as an intermediate language by implementations of other languages. This approach may be used for portability or convenience; by using C as an intermediate language, it is not necessary to develop machine-specific code generators. Some languages and compilers which have used C this way are BitC, C++, Eiffel, Gambit, GHC, Squeak, and Vala. However, C was designed as a programming language, not as a compiler target language, and is thus less than ideal for use as an intermediate language. This has led to development of C-based intermediate languages such as C--.

C has also been widely used to implement end-user applications, but much of that development has shifted to newer languages.

Syntax

Main article: C syntax

Unlike languages such as FORTRAN 77, C source code is free-form which allows arbitrary use of whitespace to format code, rather than column-based or text-line-based restrictions. Comments may appear either between the delimiters /* and */, or (in C99) following // until the end of the line.

C source files contain declarations and function definitions. Function definitions, in turn, contain declarations and statements. Declarations either define new types using keywords such as struct, union, and enum, or assign types to and perhaps reserve storage for new variables, usually by writing the type followed by the variable name. Keywords such as char and int specify built-in types. Sections of code are enclosed in braces ({ and }, sometimes called "curly brackets") to limit the scope of declarations and to act as a single statement for control structures.

As an imperative language, C uses statements to specify actions. The most common statement is an expression statement, consisting of an expression to be evaluated, followed by a semicolon; as a side effect of the evaluation, functions may be called and variables may be assigned new values. To modify the normal sequential execution of statements, C provides several control-flow statements identified by reserved keywords. Structured programming is supported by if(-else) conditional execution and by do-while, while, and for iterative execution (looping). The for statement has separate initialization, testing, and reinitialization expressions, any or all of which can be omitted. break and continue can be used to leave the innermost enclosing loop statement or skip to its reinitialization. There is also a non-structured goto statement which branches directly to the designated label within the function. switch selects a case to be executed based on the value of an integer expression.

Expressions can use a variety of built-in operators (see below) and may contain function calls. The order in which arguments to functions and operands to most operators are evaluated is unspecified. The evaluations may even be interleaved. However, all side effects (including storage to variables) will occur before the next "sequence point"; sequence points include the end of each expression statement, and the entry to and return from each function call. Sequence points also occur during evaluation of expressions containing certain operators(&&, ||, ?: and the comma operator). This permits a high degree of object code optimization by the compiler, but requires C programmers to take more care to obtain reliable results than is needed for other programming languages.

Although mimicked by many languages because of its widespread familiarity, C's syntax has often been criticized. For example, Kernighan and Ritchie say in the Introduction of The C Programming Language, "C, like any other language, has its blemishes. Some of the operators have the wrong precedence; some parts of the syntax could be better."

Some specific problems worth noting are:

Not checking number and types of arguments when the function declaration has an empty parameter list. (This provides backward compatibility with K&R C, which lacked prototypes.)
Some questionable choices of operator precedence, as mentioned by Kernighan and Ritchie above, such as == binding more tightly than & and | in expressions like x & 1 == 0, which would need to be written (x & 1) == 0 to be properly evaluated.
The use of the = operator, used in mathematics for equality, to indicate assignment, following the precedent of Fortran and PL/I, but unlike ALGOL and its derivatives. Ritchie made this syntax design decision consciously, based primarily on the argument that assignment occurs more often than comparison.
Similarity of the assignment and equality operators (= and ==), making it easy to accidentally substitute one for the other. In many cases, each may be used in the context of the other without a compilation error (although some compilers produce warnings). For example, the conditional expression in if (a=b) is true if a is not zero after the assignment.¹²
A lack of infix operators for complex objects, particularly for string operations, making programs which rely heavily on these operations (implemented as functions instead) somewhat difficult to read.
A declaration syntax that some find unintuitive, particularly for function pointers. (Ritchie's idea was to declare identifiers in contexts resembling their use: "declaration reflects use".)

Operators

Main article: Operators in C and C++

C supports a rich set of operators, which are symbols used within an expression to specify the manipulations to be performed while evaluating that expression. C has operators for:

arithmetic (+, -, *, /, %)
assignment (=) and augmented assignment (+=, -=, *=, /=, %=, &=, |=, ^=, <<=, >>=)
bitwise logic (~, &, |, ^)
bitwise shifts (<<, >>)
boolean logic (!, &&, ||)
conditional evaluation (? :)
equality testing (==, !=)
function argument collection (( ))
increment and decrement (++, --)
member selection (., ->)
object size (sizeof)
order relations (<, <=, >, >=)
reference and dereference (&, *, [ ])
sequencing (,)
subexpression grouping (( ))
type conversion ((typename))

C has a formal grammar,¹³ specified by the C standard.

"Hello, world" example

The "hello, world" example which appeared in the first edition of K&R has become the model for an introductory program in most programming textbooks, regardless of programming language. The program prints "hello, world" to the standard output, which is usually a terminal or screen display.

The original version was:

main()
{
    printf("hello, world\n");
}

A standard-conforming "hello, world" program is:¹⁴

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

The first line of the program contains a preprocessing directive, indicated by #include. This causes the preprocessor—the first tool to examine source code as it is compiled—to substitute the line with the entire text of the stdio.h standard header, which contains declarations for standard input and output functions such as printf. The angle brackets surrounding stdio.h indicate that stdio.h is located using a search strategy that prefers standard headers to other headers having the same name. Double quotes may also be used to include local or project-specific header files.

The next line indicates that a function named main is being defined. The main function serves a special purpose in C programs; the run-time environment calls the main function to begin program execution. The type specifier int indicates that the return value, the value that is returned to the invoker (in this case the run-time environment) as a result of evaluating the main function, is an integer. The keyword void as a parameter list indicates that the main function takes no arguments.¹⁵

The opening curly brace indicates the beginning of the definition of the main function.

The next line calls (diverts execution to) a function named printf, which was declared in stdio.h and is supplied from a system library. In this call, the printf function is passed (provided with) a single argument, the address of the first character in the string literal "hello, world\n". The string literal is an unnamed array with elements of type char, set up automatically by the compiler with a final 0-valued character to mark the end of the array (printf needs to know this). The \n is an escape sequence that C translates to a newline character, which on output signifies the end of the current line. The return value of the printf function is of type int, but it is silently discarded since it is not used. (A more careful program might test the return value to determine whether or not the printf function succeeded.) The semicolon ; terminates the statement.

The return statement terminates the execution of the main function and causes it to return the integer value 0, which is interpreted by the run-time system as an exit code indicating successful execution.

The closing curly brace indicates the end of the code for the main function.

Data types

Main article: C variable types and declarations

C has a static weak typing type system that shares some similarities with that of other ALGOL descendants such as Pascal. There are built-in types for integers of various sizes, both signed and unsigned, floating-point numbers, characters, and enumerated types (enum). C99 added a boolean datatype. There are also derived types including arrays, pointers, records (struct), and untagged unions (union).

C is often used in low-level systems programming where escapes from the type system may be necessary. The compiler attempts to ensure type correctness of most expressions, but the programmer can override the checks in various ways, either by using a type cast to explicitly convert a value from one type to another, or by using pointers or unions to reinterpret the underlying bits of a value in some other way.

Pointers

C supports the use of pointers, a very simple type of reference that records, in effect, the address or location of an object or function in memory. Pointers can be dereferenced to access data stored at the address pointed to, or to invoke a pointed-to function. Pointers can be manipulated using assignment and also pointer arithmetic. The run-time representation of a pointer value is typically a raw memory address (perhaps augmented by an offset-within-word field), but since a pointer's type includes the type of the thing pointed to, expressions including pointers can be type-checked at compile time. Pointer arithmetic is automatically scaled by the size of the pointed-to data type. (See Array-pointer interchangeability below.) Pointers are used for many different purposes in C. Text strings are commonly manipulated using pointers into arrays of characters. Dynamic memory allocation, which is described below, is performed using pointers. Many data types, such as trees, are commonly implemented as dynamically allocated struct objects linked together using pointers. Pointers to functions are useful for callbacks from event handlers.

A null pointer is a pointer that points to no valid location by having a value of 0.¹⁶ Dereferencing a null pointer is therefore meaningless, typically resulting in a run-time error. Null pointers are useful for indicating special cases such as no next pointer in the final node of a linked list, or as an error indication from functions returning pointers. In code, null pointers are usually represented by 0 or NULL.

Void pointers (void *) point to objects of unknown type, and can therefore be used as "generic" data pointers. Since the size and type of the pointed-to object is not known, void pointers cannot be dereferenced, nor is pointer arithmetic on them allowed, although they can easily be (and in many contexts implicitly are) converted to and from any other object pointer type.

Careless use of pointers is potentially dangerous. Because they are typically unchecked, a pointer variable can be made to point to any arbitrary location, which can cause undesirable effects. Although properly-used pointers point to safe places, they can be made to point to unsafe places by using invalid pointer arithmetic; the objects they point to may be deallocated and reused (dangling pointers); they may be used without having been initialized (wild pointers); or they may be directly assigned an unsafe value using a cast, union, or through another corrupt pointer. In general, C is permissive in allowing manipulation of and conversion between pointer types, although compilers typically provide options for various levels of checking. Some other programming languages address these problems by using more restrictive reference types.

Arrays

Array types in C are traditionally of a fixed, static size specified at compile time. (The more recent C99 standard also allows a form of variable-length arrays.) However, it is also possible to allocate a block of memory (of arbitrary size) at run-time, using the standard library's malloc function, and treat it as an array. C's unification of arrays and pointers (see below) means that true arrays and these dynamically-allocated, simulated arrays are virtually interchangeable. Since arrays are always accessed (in effect) via pointers, array accesses are typically not checked against the underlying array size, although the compiler may provide bounds checking as an option. Array bounds violations are therefore possible and rather common in carelessly written code, and can lead to various repercussions, including illegal memory accesses, corruption of data, buffer overruns, and run-time exceptions.

Although C supports static arrays, it is not required that array indices be validated (bounds checking). For example, one can try to write to the sixth element of an array with five elements, generally yielding undesirable results. This type of bug, called a buffer overflow or buffer overrun, is notorious for causing a number of security problems. Since bounds checking elimination technology was largely nonexistent when C was defined, bounds checking came with a severe performance penalty, particularly in numerical computation. A few years earlier, some Fortran compilers had a switch to toggle bounds checking on or off; however, this would have been much less useful for C, where array arguments are passed as simple pointers.

C does not have a special provision for declaring multidimensional arrays, but rather relies on recursion within the type system to declare arrays of arrays, which effectively accomplishes the same thing. The index values of the resulting "multidimensional array" can be thought of as increasing in row-major order.

Multidimensional arrays are commonly used in numerical algorithms (mainly from applied linear algebra) to store matrices. The structure of the C array is well suited to this particular task. However, since arrays are passed merely as pointers, the bounds of the array must be known fixed values or else explicitly passed to any subroutine that requires them, and dynamically sized arrays of arrays cannot be accessed using double indexing. (A workaround for this is to allocate the array with an additional "row vector" of pointers to the columns.)

C99 introduced "variable-length arrays" which address some, but not all, of the issues with ordinary C arrays.

Array-pointer interchangeability

A distinctive (but potentially confusing) feature of C is its treatment of arrays and pointers. The array-subscript notation x[i] can also be used when x is a pointer; the interpretation (using pointer arithmetic) is to access the (i + 1)th object of several adjacent data objects pointed to by x, counting the object that x points to (which is x[0]) as the first element of the array.

Formally, x[i] is equivalent to *(x + i). Since the type of the pointer involved is known to the compiler at compile time, the address that x + i points to is not the address pointed to by x incremented by i bytes, but rather incremented by i multiplied by the size of an element that x points to. The size of these elements can be determined with the operator sizeof by applying it to any dereferenced element of x, as in n = sizeof *x or n = sizeof x[0].

Furthermore, in most expression contexts (a notable exception is as operand of sizeof), the name of an array is automatically converted to a pointer to the array's first element; this implies that an array is never copied as a whole when named as an argument to a function, but rather only the address of its first element is passed. Therefore, although function calls in C use pass-by-value semantics, arrays are in effect passed by reference.

The number of elements in a declared array x can be determined as sizeof x / sizeof x[0].

An interesting demonstration of the interchangeability of pointers and arrays is shown below. The four assignments are equivalent and each is valid C code.

/* x is an array OR a pointer. i is an integer. */
 
x[i] = 1;         /* equivalent to *(x + i) */
*(x + i) = 1;
*(i + x) = 1;
i[x] = 1;         /* equivalent to *(i + x) */

Note that although all four assignments are equivalent, only the first represents good coding style. The last line might be found in obfuscated C code.

Despite this apparent equivalence between array and pointer variables, there is still a distinction to be made between them. Even though the name of an array is, in most expression contexts, converted into a pointer (to its first element), this pointer does not itself occupy any storage, unlike a pointer variable. Consequently, what an array "points to" cannot be changed, and it is impossible to assign a value to an array variable. (Array values may be copied, however, e.g., by using the memcpy function.)

Memory management

One of the most important functions of a programming language is to provide facilities for managing memory and the objects that are stored in memory. C provides three distinct ways to allocate memory for objects:

Static memory allocation: space for the object is provided in the binary at compile-time; these objects have an extent (or lifetime) as long as the binary which contains them is loaded into memory
Automatic memory allocation: temporary objects can be stored on the stack, and this space is automatically freed and reusable after the block in which they are declared is exited
Dynamic memory allocation: blocks of memory of arbitrary size can be requested at run-time using library functions such as malloc from a region of memory called the heap; these blocks persist until subsequently freed for reuse by calling the library function free

These three approaches are appropriate in different situations and have various tradeoffs. For example, static memory allocation has no allocation overhead, automatic allocation may involve a small amount of overhead, and dynamic memory allocation can potentially have a great deal of overhead for both allocation and deallocation. On the other hand, stack space is typically much more limited and transient than either static memory or heap space, and dynamic memory allocation allows allocation of objects whose size is known only at run-time. Most C programs make extensive use of all three.

Where possible, automatic or static allocation is usually preferred because the storage is managed by the compiler, freeing the programmer of the potentially error-prone chore of manually allocating and releasing storage. However, many data structures can grow in size at runtime, and since static allocations (and automatic allocations in C89 and C90) must have a fixed size at compile-time, there are many situations in which dynamic allocation must be used. Prior to the C99 standard, variable-sized arrays were a common example of this (see malloc for an example of dynamically allocated arrays).

Automatically and dynamically allocated objects are only initialized if an initial value is explicitly specified; otherwise they initially have indeterminate values (typically, whatever bit pattern happens to be present in the storage, which might not even represent a valid value for that type). If the program attempts to access an uninitialized value, the results are undefined. Many modern compilers try to detect and warn about this problem, but both false positives and false negatives occur.

Another issue is that heap memory allocation has to be manually synchronized with its actual usage in any program in order for it to be reused as much as possible. For example, if the only pointer to a heap memory allocation goes out of scope or has its value overwritten before free() has been called, then that memory cannot be recovered for later reuse and is essentially lost to the program, a phenomenon known as a memory leak. Conversely, it is possible to release memory too soon and continue to access it; however, since the allocation system can re-allocate or itself use the freed memory, unpredictable behavior is likely to occur. Typically, the symptoms will appear in a portion of the program far removed from the actual error, making it difficult to track down the problem. Such issues are ameliorated in languages with automatic garbage collection.

Libraries

The C programming language uses libraries as its primary method of extension. In C, a library is a set of functions contained within a single "archive" file. Each library typically has a header file, which contains the prototypes of the functions contained within the library that may be used by a program, and declarations of special data types and macro symbols used with these functions. In order for a program to use a library, it must include the library's header file, and the library must be linked with the program, which in many cases requires compiler flags (e.g., -lm, shorthand for "math library").

The most common C library is the C standard library, which is specified by the ISO and ANSI C standards and comes with every C implementation (“freestanding” [embedded] C implementations may provide only a subset of the standard library). This library supports stream input and output, memory allocation, mathematics, character strings, and time values.

Another common set of C library functions are those used by applications specifically targeted for Unix and Unix-like systems, especially functions which provide an interface to the kernel. These functions are detailed in various standards such as POSIX and the Single UNIX Specification.

Since many programs have been written in C, there are a wide variety of other libraries available. Libraries are often written in C because C compilers generate efficient object code; programmers then create interfaces to the library so that the routines can be used from higher-level languages like Java, Perl, and Python.

Language tools

Tools have been created to help C programmers avoid some of the problems inherent in the language, such as statements with undefined behavior or statements that are not a good practice because they are more likely to result in unintended behavior or run-time errors.

Automated source code checking and auditing are beneficial in any language, and for C many such tools exist, such as Lint. A common practice is to use Lint to detect questionable code when a program is first written. Once a program passes Lint, it is then compiled using the C compiler. Also, many compilers can optionally warn about syntactically valid constructs that are likely to actually be errors. MISRA C is a proprietary set of guidelines to avoid such questionable code, developed for embedded systems.

There are also compilers, libraries and operating system level mechanisms for performing array bounds checking, buffer overflow detection, serialization and automatic garbage collection, that are not a standard part of C.

Tools such as Purify, Valgrind, and linking with libraries containing special versions of the memory allocation functions can help uncover runtime memory errors.

Related languages

C has directly or indirectly influenced many later languages such as Java, Perl, PHP, JavaScript, LPC, C# and Unix's C Shell. The most pervasive influence has been syntactical: all of the languages mentioned combine the statement and (more or less recognizably) expression syntax of C with type systems, data models and/or large-scale program structures that differ from those of C, sometimes radically.

When object-oriented languages became popular, C++ and Objective-C were two different extensions of C that provided object-oriented capabilities. Both languages were originally implemented as source-to-source compilers -- source code was translated into C, and then compiled with a C compiler.

The C++ programming language was devised by Bjarne Stroustrup as one approach to providing object-oriented functionality with C-like syntax. C++ adds greater typing strength, scoping and other tools useful in object-oriented programming and permits generic programming via templates. Nearly a superset of C, C++ now supports most of C, with a few exceptions (see Compatibility of C and C++ for an exhaustive list of differences).

Objective-C was originally a very "thin" layer on top of, and remains a strict superset of C that permits object-oriented programming using a hybrid dynamic/static typing paradigm. Objective-C derives its syntax from both C and Smalltalk: syntax that involves preprocessing, expressions, function declarations and function calls is inherited from C, while the syntax for object-oriented features was originally taken from Smalltalk.

The D programming language makes a clean break with C while maintaining the same general syntax, unlike C++, which maintains nearly complete backwards compatibility with C. D abandons a number of features of C which Walter Bright (the designer of D) considered undesirable, including the C preprocessor and trigraphs. Some, but not all, of D's extensions to C overlap with those of C++.

Limbo is a language developed by a team at Bell Labs, and while it retains some of the syntax and the general style of C, it also includes garbage collection and CSP-based concurrency.

Python has a different sort of C heritage. While the syntax and semantics of Python are radically different from C, the most widely used Python implementation, CPython, is an open source C program. This allows C users to extend Python with C, or embed Python into C programs. This close relationship is one of the key factors leading to Python's success as a general-use dynamic language.

Perl is another example of a popular programming language rooted in C. The overall structure of Perl derives broadly from C. The standard Perl implementation is written in C and supports extensions written in C.

References

^ ^a ^b Kernighan; Dennis M. Ritchie (March 1988). The C Programming Language (2nd ed.). Englewood Cliffs, NJ: Prentice Hall. ISBN 0-13-110362-8. http://cm.bell-labs.com/cm/cs/cbook/. Regarded by many to be the authoritative reference on C.
^ ^a ^b Dennis M. Ritchie (January 1993). "The Development of the C Language". http://cm.bell-labs.com/cm/cs/who/dmr/chist.html. Retrieved Jan 1 2008. "The scheme of type composition adopted by C owes considerable debt to Algol 68, although it did not, perhaps, emerge in a form that Algol's adherents would approve of."
^ Stewart, Bill (January 7, 2000). "History of the C Programming Language". Living Internet. http://www.livinginternet.com/i/iw_unix_c.htm. Retrieved 2006-10-31.
^ Patricia K. Lawlis, c.j. kemp systems, inc. (1997). "Guidelines for Choosing a Computer Language: Support for the Visionary Organization". Ada Information Clearinghouse. http://archive.adaic.com/docs/reports/lawlis/k.htm. Retrieved 2006-07-18.
^ "Programming Language Popularity". 2009. http://www.langpop.com/. Retrieved 2009-01-16.
^ "TIOBE Programming Community Index". 2009. http://www.tiobe.com/index.php/content/paperinfo/tpci/index.html. Retrieved 2009-05-06.
^ "comp.lang.c FAQ entry concerning boolean values". http://c-faq.com/bool/booltype.html. Retrieved 2010-07-05.
^ "Jargon File entry for nasal demons". http://www.catb.org/jargon/html/N/nasal-demons.html.
^ Kernighan, Brian W.; Dennis M. Ritchie (February 1978). The C Programming Language (1st ed.). Englewood Cliffs, NJ: Prentice Hall. ISBN 0-13-110163-3. This book was the first widely available book on the C programming language. The version of C described in this book is often referred to as K&R C.
^ Dr. Dobb's Sourcebook. U.S.A.: Miller Freeman, Inc.. Nov/Dec 1995 issue.
^ "Using C for CGI Programming". linuxjournal.com. 2005-03-01. http://www.linuxjournal.com/article/6863. Retrieved 2010-01-04.
^ "10 Common Programming Mistakes in C". Cs.ucr.edu. http://www.cs.ucr.edu/~nxiao/cs10/errors.htm. Retrieved 2009-06-26.
^ Harbison, Samuel P.; Guy L. Steele (2002). C: A Reference Manual (5th ed.). Englewood Cliffs, NJ: Prentice Hall. ISBN 0-13-089592-X. This book is excellent as a definitive reference manual, and for those working on C compilers. The book contains a BNF grammar for C.
^ The original example code will compile on most modern compilers that are not in strict standard compliance mode, but it does not fully conform to the requirements of either C89 or C99. In fact, C99 requires that a diagnostic message be produced.
^ The main function actually has two arguments, int argc and char *argv[], respectively, which can be used to handle command line arguments. The C standard requires that both forms of main be supported, which is special treatment not afforded any other function.
^ ISO/IEC 9899:1999 specification, p. 47, § 6.3.2.3 (3)

External links

Wikiversity has learning materials about Topic:C

ISO C Working Group official website
comp.lang.c Frequently Asked Questions
ISO/IEC 9899. Official C99 documents.
The current draft Standard (C99 with Technical corrigenda TC1, TC2, and TC3 included)PDF (3.61 MB)
ANSI C Standard (ANSI X3J11/88-090) (Published May 13, 1988), Third Public Review
ANSI C Rationale (ANSI X3J11/88-151) (Published Nov 18, 1988)

v • d • e Integrated development environments for C and C++

Open source	Anjuta · Code::Blocks · CodeLite · Dev-C++ · Eclipse · Geany · GNAT Programming Studio · KDevelop · Kuzya · MonoDevelop · NetBeans · QDevelop · Qt Creator · wxDev-C++ · Ultimate++

Freeware	Visual Studio Express · Pelles C · Sun Studio · Xcode

Retail	C++Builder · Code Crusader IDE · Visual Studio

see also : Category:Integrated development enviroments • Comparison of Integrated development enviroments

v • d • e C programming language

Libraries	C standard library · glibc · dietlibc · uClibc · Newlib · EGLIBC

Features	String · Syntax · Preprocessor · Variable types and declarations · Functions

Select descendants	C++ · C++0x · Objective-C · D · C# · Vala

C and other languages	C and C++ (Compatibility · Operators) · Comparison of Pascal and C · C to Java byte-code compiler

Category

About programming language | JackOnline: Recently some friends who want to major in programming ask me how to choose a programming language, and I say it all depends. All the programming languages will be compiled into machine language, that is 10101010… ... Linux:C. MacOS:C&C++. Symbian OS:C++. 15.Media player. Nullsoft Winamp:C++. Microsoft Windows Media Player:C++. Microsoft Windows Media Player:C++. Share/Bookmark. Related posts: A collection of 20 java language development environment · The top ten greatest ...
C Tutorial–The C Programming Language for Beginners: Programming in C is so simple that even people with no background in programming can start learning how to program immediately.
Help setting up open-source project for charity: Scripting will be done using Tagmata Programming Language (TPL) - the syntax is similar to Javascript, but uses PHP for the implementation, so the names and behaviour of functions would generally be like PHP. ... Posts: 16550. It would seem you've picked a poor choice of language for getting this done fast. But just as an advance for you: C++ will speed up the development and can interface with C. It won't be as pretty, but it will still get done faster than purely C. ...
The end of Google - cboard.cprogramming.com: Originally Posted by brewbuck: Reimplementing a large system in another language to get a 25% performance boost is nonsense. It would be cheaper to just get a computer which is 25% faster. Quiet Technologies... that make some noise. ...
Help with programming my mobile robotic arm in C: I used their IDE when I was testing a few things that was in Basic language. There is an option under tools/preferences so I can use C/C++ which I do have some knowledge of http://www.lynxmotion.com/images/html/build147.htm. ...
C++ Video Tutorials | Ebooks share | Free Download Ebooks | Ebook ...: Tags: Arrays, beginner tutorials, c programming language, c programming tutorials, c tutorials, chapter, Control, control statements, Data, game loop, hotfile, introduction to c, kbps mpeg, Operators, Programming, Spoonfeed, tutorials c ...
Learn Programming Language, List of Programming Languages ...: Programming languages have a written order of their syntax and semantics. Few languages are defined by a requirement document. Example, the C programming language is precise by an ISO Standard. ...
The Top Ten Concepts for Linux Beginners – Number 7, Shells and ...: Historically Unix used the Bourne shell, the C shell based on the C programming language, and the Korn shell. Linux's most widely used shell is Bash, also spelled BASH, the (Bourne-Again Shell). Damn Small Linux offers many shells but ...
Insert Into Array Function Problem - GIDForums: Two-Tier data dissemination code installation problem, nidhibansal1984, Computer Software Forum - Linux, 6, 16-Sep-2007 10:13. return string from a function, Howard_L, C Programming Language, 4, 17-Aug-2007 23:56 ...
C Programming Tutorial 1 Learn C Programming: Game Programming ...: The C Programming language is a great place to start for anyone who would like to learn computer programming. C is relatively easy to learn but can be very powerful While its a much older language and not object oriented, it can be used ...
C Programming with Free Compilers: Tutorials for novices using ...: A guide to installing and setting up free C compilers, and taking some first steps with the C programming language, in tutorial format.
Free Pdf: The C programming Language - Free PDF & PPT (PowerPoint ...: The C programming Language 7. Variable Argument Lists: 8. Non-local Jumps:9. Signals: 10. Date and Time Functions: 11... A Tutorial Introduction. Getting.
How to change text colors in C? - C Programming: So the new syntax to blink the text in c programming language would be textattr(BLINK+BLACK+WHITE); There are some limitations on foreground and background colors, like you can not use white color as the background. ...
I'm feeling very virtual - cboard.cprogramming.com: Reimplementing a large system in another language to get a 25% performance boost is nonsense. It would be cheaper to just get a computer which is 25% faster. Quiet Technologies... that make some noise. Mario F. is online now ...
C Program to Propose a girl | C language Funny Programs | Funny ...: C Program to Propose a girl. Posted by Akash Padhiyar On September - 9 - 2010. /*C Program to Propose a girl*/ #include #include #define Cute beautiful_lady main() { goto college; scanf(“100%”,&ladies); if(lady ==Cute) line++;. while( !reply ) { printf(“I Love U”); scanf(“100%”,&reply); } if(reply == “GAALI”) main(); /* go back and repeat the process */ ... Object Oriented Programming With C++ · BCA-E-Books. Posted by Akash Padhiyar ...
What code could i use? - cboard.cprogramming.com: Help me guys! I cannot think what code can I use to compare 2 numbers? im just a freshman at Programming in Turbo C.... can someone help me? output: ... In fact, you can learn a lot by asking questions to people and then thinking on them. You can become an expert in a language by asking questions. Far faster than empirical tests and googling. Troubleshooting is a good thing to learn, true, but you shouldn't have to overdo it. All people cannot do it the hard way. ...
How to get a list of files contained in a folder - GIDForums: Str_Misaligned in Double Link List, Peter_APIIT, C Programming Language, 1, 29-Feb-2008 20:50. Airport Log program using 3D linked List : problem reading from file, batrsau, C Programming Language, 11, 29-Feb-2008 07:44 ...
Best Programming Language to Start With: How to Plan your First ...: Technical universities and colleges throughout the world often choose C as the first programming language to teach their students. Often cited reasons for this choice include the low-level and function-oriented approach required by the ...
Getting Started With C Programming: The C programming language has been around since 1972 and is still widely used today. That is because it is a very efficient and portable language which can provide high levels of performance on most hardware architectures. ...
MathWorks MATLAB R3010B » Free Software and Shareware Downloads ...: MATLAB - a high-level technical computing language, interactive environment for algorithm design and modern tools of data analysis. MATLAB compared to traditional programming languages (C / C, Java, Pascal, FORTRAN) allows an order to ...
Basics of C programming Language: A programming language is designed to help in processing of certain data and to provide useful information to the user. There are lots of programming languages today that satisfy different needs of the user. For example: C, C++, Java, ...
How to Use a Pointer in C Programming: The C programming language is used to design low-level code for applications such as circuits and robotics. This language is somewhat different than the C++ language, which implements classes and other high level objects. ...
Programming Language used in Cocoa Programming: Objective-C is a simple and elegant extension to C, and mastering it will take about two hours if you already know C and an object-oriented language, such as Java or C++.
The Importance of Objective C Programming Language in iPhone ...: Using the Cocoa Touch framework and Objective-C programming language, the developer can create interactive applications for the iPhone with ease. Objective-C is the most important iPhone programming language in developing applications. ...
Programming For The Absolute Beginner For The Absolute Beginner ...: Objective-C for iPhone Developers: A Beginner's Guide shows you how to use the Objective-C programming language, Apple's Foundation framework, the iPhone SDK, and the Xcode development environment. The first stop for aspiring iPhone ...
The C Book: Featuring the ANSI C Standard | Ebooks share | Free ...: This book presents an introduction to the C programming language, featuring a structured approach and aimed at professionals and students with some experience of high-level languages. Features *includes embedded summary material in ...
How would I go about learning to programme iPhone Apps? | TechManch: Posted 6 hours ago. iphone apps are program on macs and use objective c programming language so you need a mac and some objective c books. author · truekill46. Posted 6 hours ago. You'll need a mac if you want to program apps, ...
Understanding the Limitations of C Numeric Data Types: C is a fast and powerful programming language. However, the unwary programmer may find their program produces some unexpected results. Find out why.
Creating Functions in C Programming: C has been a popular programming language for nearly 40 years. One reason for this is the fact that C is cross-platform and produces executables that are native to each operating system. Another reason is the ease with which the new ...
Function call - cboard.cprogramming.com: Using: Microsoft Windows™ 7 Professional (x64), Microsoft Visual Studio™ 2010 Ultimate, C++0x "Thanks Elysia. You're a programming master! How the hell do you know every thing?" "Thanks for all your help. It's obvious yall really know ...
Introduction To GNU C++: The no cost alternative to the BIG GUYS: Some assume you already know the C programming syntax. Others adopt the view that you may be a programmer of a different language but know nothing about C or C++. You must review the description of each to find the tutorial best suited ...
Using Libraries with the Processing Programming Language: Programming in Processing with Libraries. There are a number of libraries that can be used for a project. One example is the Interfascia graphical user interface library: import interfascia.*;. GUIController c;. IFButton save; ...
Programming Language Popularity: StackOverflow and Ohloh ...: CSS and Make are also relatively small languages with specific uses rather than general purpose programming languages. The fact that C++ was developed as an enhancement to the C programming language explains why there are more questions ...
Portable Compiler Rapidshare Free Full Downloads with Hotfile and ...: Portable C Compiler Rapidshare portable c compiler Crack Portable C Compiler Megaupload portable c compiler torrent portable c compiler serial, Full Versions Rapidshare Direct Results Download Portable C Compiler from Rapidshare Crack .... (like Intellisense), project conversion, and batch building features, as well as many other advanced features. Download your copy today to begin writing, debugging, and building applications in your favorite programming language. ...
Using a MySQL Database with C++: How to Access MySQL Stored ...: One of the most powerful combinations that any programmer can use is the combination of C++ and MySQL - a flexible programming language with a multi-platform and stable database; but this may seem an intimidating task to the new software developer. It's not. ... deterministic. begin. declare c int;. select count(*) into c from users where active = True;. return c;. end. //. delimiter ;. This code simply returns the number of active users (from the table users). ...
Basic Command Line Calculator in the C Programming Language: So I heard a while back that the C programming language is similar to PHP. Of coarse the gears in my brain started turning (maybe you heard the wood burning) which meant that I had to give it a go. After Googling some reference material ...
Opening for M.Sc. Freshers (Computer Science/Maths/Statistics ...: 1) Working knowledge in “C” Programming language with Data Structures. 2 )Understanding of Object Oriented concepts. 3 )Added advantage if they have a Familiarity with Visual Basic/ VBScript/ Visual Basic for Applications (VBA) ...
Microsoft Dynamics Gp Great Plains East European Options Overview ...: Microsoft Dynamics GP is originally and currently written (meaning programmed) in Great Plains Dexterity, which in turn is the shell, developed in C programming language. C is of course partially operating system independent, ...
Codi Milo Rapidshare Free Full Downloads with Hotfile and ...: Objective-C is the programming language for writing native iPhone and Mac applications. It's also the language that Apple uses to build their own applications and frameworks. So, if you know Objective-C, you have a lot of power at your ...
Python 3.2 Alpha 2 for Linux: Powerful programming language | All ...: Python 3.2 Alpha 2 for Linux: Powerful programming language | All about linux @ Linuxinet.Com, the most comprehensive source for Linux Update. Includes micosoft vs linux, windows vs linux, linux the fact free linux ebooks, free linux software, free linux news, ... Extensions and modules easily written in C, C + + (or Java for Jython, or. NET languages for IronPython) * Embeddable within applications as a scripting interface. Download Python 3.2 Alpha 2 for Linux (10.6 MB) ...
Free PDF: ANSI C Programming Language - Free ebook manual download ...: Singh Computer Science 217: ANSI C Programming Language Page 14 September 7, 1997 ANSI C Programming Language • A small, general-purpose … September 7, 1997 ANSI C Programming Language • A small, general-purpose, initially systems ...
Learning a programming language – C# | Alltimedefense: So after diving into the Programming in LUA book, I decided a better foundation of programming was needed. I read reviews on the book Programming in the Key of.
R-Chart: Programming Language Popularity: StackOverflow and Ohloh: For instance the C programming language might be compared with a record pertaining to the third letter of the alphabet. This is not a problem in the current example because the specific domain of both data sets is programming languages. ...
Apple loosens rules for programming Apps | Thinkcrack: This includes the latest version of Adobe Flash is a compiler that translates the Flash code in Objective C, so in the programming language for “native” iPhone apps. The Flash multimedia technology itself is not supported by Apple on ...
CUDA Example Introduction GeneralPurpose GPU Programming ...: ... then take the skills you learn and use them for more practical Python programming applications and real-world programming scenarios. Better still, by the time you finish this book you will be able to apply the basic principles you've learned to the next programming language you tackle. Create simple, fun games while you learn to program with Python ... Beginning iPhone SDK Programming With Objective-C Publisher: Wrox 2010 | 552 Pages | ISBN: 0470500972 | PDF | 46 MB ...
My First Interaction With C programming Language: Rs.580.00. A Video Tutorial of C programming Language. Total Running Time : 15 hours. Language : Hindi. It Contains 14 chapters: Rs.580.00. Order From Ebay. Quantity: read more.
Beginning Programming with C++ For Dummies (For Dummies (Computer ...: C++ is an object-oriented programming language commonly adopted by would-be programmers. This book explores the basic development concepts and techniques of C++ and explains the "how" and "why" of C++ programming from the ground up. ...
Linux Today - April Headline: C programming language back at ...: So the main reason for C's number 1 position is not C's uprise, but the decline of its competitor Java. Java has a long-term downward trend. It is losing ground to other languages running on the JVM. An example of such a language is ...
Programming Books, part 4: The C Programming Language | The ...: While I agree that The C Programming Language is a very good example of how to write a book on a computer language, I am far from certain that I would call it a programming book: It only deals with programming as far is necessary to ...
Alphabetizing a linked list in C: A hands-on tutorial covering C ...: We are also using the C programming language, which means that we cannot encapsulate any of the abstract data types in a class. C++ programmers and budding C programmers hoping to move to C++ will appreciate the differences between this ...
THE OBJECTIVE C PROGRAMMING LANGUAGE | Ebook Manual Pdf: Download The Objective C Programming Language.pdf.
TRAC Interpreter -- Sixties programming language « Python recipes ...: A Python implementation of an interpreter for the TRAC programming language developed by Calvin Mooers in the early 1960s. This implementation reconstructs Mooers' original algorithm in Python and supports only a limited number of TRAC ... pos, n): chars = [] for i in range(n): c = scan_char(list_, pos + i) if c: chars.append(c) return "".join(chars) class Processor(object): def __init__(self, program=""): self.work = [] # workspace containing current TRAC program self.sp ...
The C Programming Language by brian W. Kernighan and Dennis M ...: THE C PROGRAMMING LANGUAGE. Writer : Brian W. Kernighan and Dennis M. Ritchie. Publisher : Prentice−Hall. ISBN 0−13−110362−8. ISBN 0−13−110370−9. CONTENTS. Chapter 1: A Tutorial Introduction. 1. Getting Started ...
Java Programming for a Beginner, 5-disk DVD Complete Training ...: I have done quite a bit of programming in assembler, C, and Visual Basic. And I needed to learn Java. I'd recommend this set to anyone wanting to learn the language and also to others who know it but learned from a different sources. ...
Programming in Objective-C 2.0, 2/e Kindle Books: From the author of “Programming in C Programming in Objective-C 2.0, the new programmer a complete step-by-step introduction into Objective-C language. The book does never assume previous experience of either C or object-oriented ...
Introduction to C# Programming: C# Programming for existing C and ...: So, what would the casual programmer get out of C# programming? In reality, it will prove easiest to learn of all the 'modern' languages. It would make a great teaching language if not for the heavy influences of C making it a little ...
FYB's Lament: the future of programming - C Board: Is it just that you would rather use the C++ language, or is it something else? I felt much the same way a while ago, but I realized that what I enjoyed so much about programming in C was more of a 'style'. ...
Open Thread: What's Your Favorite Programming Language? «: I?ll use C, C++ or Javascript when I must, but always Python when I have a choice. … read more [...] Bigger Faster Stronger » Blog Archive » Comment on Open Thread: What's Your Favorite Programming Language … January 14, 2008Tracked on ...
introduction to c programming: C++ was developed in 1980s in the Bell Laboratories by Bjarne Stroustrup as an object oriented programming language. This language is considered by many as an extension of the programming language C. The extension of programming ...
Free C/C++ interpreter Ch 4.0 released - adamwire's blog: Ch in Windows includes over 100 Unix commands are commonly used in portable shell programming. Ch can also be used for login shell, like sh, csh and ksh. Ch bridges the differences in C language and shell languages. ...
SAVE $32.51 - C Programming Language (2nd Edition) $34.49: SAVE $32.51 - C Programming Language (2nd Edition) $34.49. http://dealnay.com/761216/c-programming-language-2nd-edition.html.
Programming News – Sun Java | I Know Computers Well: Java is a programming language originally developed by Sun Microsystems and released in 1995 as a core component of Sun's Java platform. The language derives much of its syntax from C and [[C++]] but has a simpler object model and fewer ...
R-Chart: GitHub Stats on Programming Languages: R is ranked 25th with 191 repositories or about 0.06% and only 6 projects behind the D programming language. The top 5 are scripting languages, Java ranks 6th and the C family rounds out the top ten. Relatively open languages lead the ...
C and C++: Career Essential or Outdated Programming Skills ...: Programming skills remain exceptionally valuable, but which programming language should you learn? Here are some reasons why you should seriously consider C, C#, and C++ languages.
The C Programming Language: The C Programming Language Rapidshare The C Programming Language Crack The C Programming Language Megaupload The C Programming Language torrent The C Programming Language serial, Full Versions Rapidshare Direct Results Download The C ...
Can programming language names be trademarks? | opensource.com: So do people think of the names of programming languages as trademarks? For some programming languages, there is clearly no single entity that claims ownership. Fortran, Ada, C, C++, Extended Pascal, and Basic are all defined by ISO ...
C++ ? getting started?: 3. when you were 15 were where u at in programming. i just made an average calculator. 4. What books would be good for learning the language im looking into the books of the guy that made the language since that makes sense but if you ... Using: Microsoft Windows™ 7 Professional (x64), Microsoft Visual Studio™ 2010 Ultimate, C++0x "Thanks Elysia. You're a programming master! How the hell do you know every thing?" "Thanks for all your help. It's obvious yall really know ...
Ruby Programming Language : Ajax Blog Ajax Tutorial Examples: Ruby easily developed using C language such as Python using SWIG interface. 10. Ruby was born from the community, so that Ruby has the support of the community who are ready to help you if you are having difficulties. ...
Objective-C for Absolute Beginners: iPhone and Mac Programming ...: Who this book is for. Everyone! This book is for anyone who wants to learn to develop applications for the Mac or apps for the iPhone and iPad using the Objective-C programming language. No previous programming experience is necessary. ...
Features of C Programming Language | Learn C Programming: Features of C Programming Language : 1 . Low Level Features : It is Closely Related to Lower level Language such as "Assembly Language"; It is easy to write assembly codes in C. 2 . Portability : C Programs are portable i.e they can be ...
Microeconomics Theory and Applications 9th edition by Browning ...: -The C Programming Language 2nd ed. by Kernighan & Ritchie -C++ how to program 7e by Deitel Testbank - Solution Manual - LMSOL. -Automatic Control Systems 9e Kuo Farid Golanraghi Solution Manual -Fundamentals of Power Semiconductor ...
Is C dead?(PROGRAMMING LANGUAGE).: If you do have a significant amount of C code investment, it is important to understand not only the key C programming language strengths and weaknesses but also best practices when integrating C code into applications written in ...
Getting Started in C++ Programming: How to Learn to Program in C++ ...: Some people advocate ignoring C completely when trying to learn C++. The issue created by this is simple : for a non-programmer, there are so many concepts that they need to know, that they may as well learn a programming language at ...
Requirement of Programmer at Vision Beyond Corporation Hyderabad ...: Working knowledge in "C" Programming language with Data Structures; Understanding of Object Oriented concepts; Added advantage if they have a Familiarity with Visual Basic/ VBScript/ Visual Basic for Applications (VBA) ...
Buy Your Programming in C, 3/e From Amazon!: Although the C programming language hasn't undergone any major changes, it's enjoying new life among game programmers and small device programmers, where its simple elegance makes it the ideal choice for small fast programs. ...
[HF]The C Programming Language Special Edition | Ebookee Free ...: Download [HF]The C Programming Language Special Edition - Free chm, pdf ebooks rapidshare download, ebook torrents bittorrent download.
Which is best web development language? | Work at Home: While Java, C and C++ are most popular for programming language, but PHP which solely created only for _web development language_ came in number for according to TIOBE Programming Community Index for June 2010. ...
jQuery For Dummies® | capacitación en la Web gratis: I enjoyed it so much that when I decided to learn C (the programming language) my first thought was C for Dummies. It was one of the funniest books I've ever read. I laughed out loud I don't know how many times. ...
Programming the iPhone 101 | machine project: Building applications on the iPhone requires some knowledge of the Objective-C programming language. We'll cover this in the workshop, but prior programming knowledge is HIGHLY recommended, and a working familiarity with objects and ...
Wrox Php Rapidshare Free Full Downloads with Hotfile and ...: Synonymous with writing code in Visual Studio 2010, Visual Basic is an incredibly popular programming language. Its speed and ease of use make it a frequent first choice for new programmers, as well as a heavily favored choice for the more experienced set eager to learn Visual Basic's latest iteration. This beginning guide provides you with a solid ... Beginning iPhone SDK Programming With Objective-C Publisher: Wrox 2010 | 552 Pages | ISBN: 0470500972 | PDF | 46 MB ...
[FS] Windows Embedded POSReady 2009 SP3 x86 Multi Retail Box (2010 ...: POSReady 2009 supports the program, based at the programming language Microsoft C #, VB.NET, Visual Basic, Visual C, Visual J, Visual FoxPro as well as any other language that is used to write programs under or Windows XP. ...
Introduction to Microsoft Silverlight: Behind Silverlight is XAML (pronounced as zammel) and codebehind programming language (C # or Visual Basic). XAML is eXtensible application markup language which is a declarative language to declare objects and controls in XML fashion. ...
C for microcontrollers: The main reason for this is that the Pascal language is not popular in comparison with the programming language C. Only users can refer to the tutorials for the C programming language mastery C. 51 and 51 are Turbo Pascal KSC some of ...
What is the best software programming language equivalent to PHP?: 4 Responses to “What is the best software programming language equivalent to PHP?” David D says: August 31, 2010 at 4:43 pm. PHP is an object oriented programming language. While there are others with similar capabilities, none will be as much ... http://www.cprogramming.com/tutorial.html#c++tutorial … and get a good free IDE for it here: http://www.bloodshed.net/devcpp.html. candy90q says: August 31, 2010 at 5:00 pm. C++. HandyManOrNot says: August 31, 2010 at 5:17 pm ...
Apple Replacing Objective C With New Programming Language For iOS ...: It is my belief that Apple is definitely working on a new language to surpass Objective-C as their intended, primary, publicly recommended programming language, which I will call “xlang”.” The new language is expected to be based off ...
Senior Development Engineer- Braking Systems Job - Warwickshire ...: Excellent software application skills; familiarity with C programming language for PC & embedded applications - Experience of vehicle electrical systems, and excellent problem solving ability - Flexibility in accepting varying work ...
INTRODUCTION TO OBJECT ORIENTED PROGRAMMING USING C++ | Ebook ...: However, this is not a course for learning the C++ programming language. If you are interested in learning the language itself, you might want to go through other tutorials, such as C++: Annotations by Frank Brokken and Karel Kubat. ... For example, there are programs written in procedural languages like Pascal or C which use object-oriented concepts. But there exist a few important features which these languages won't handle or won't handle very well, respectively. ...
INCOMPATIBILITIES BETWEEN ISO C AND ISO C++ | Ebook Manual Pdf: The C programming language began to be standardized some time around 1985 by the ANSI X3J9 committee. Several years of effort went by, and in 1989 ANSI approved the new standard. An ISO committee ratified it a year later in 1990 after ...
Bioeng-Medical: The C Programming Language by BRAIN W.KERNIGHAN ...: Some compilers which use C this way are BitC, Gambit, the Glasgow Haskell Compiler, Squeak, and Vala. However, C was designed as a programming language, not as a compiler target language, and is thus less than ideal for use as an ...
History of the C Programming Language: The C programming language was first developed between 1969 and 1973 by a team from Bell Telephone Laboratories. Many of the principles and ideas used in this language were taken from the programming language named 'B' (created by Ken ...
hu-tui.com » Blog Archive » CEVA, in order to put out high ...: The advanced data of DSP buffered framework and software development environment to simplify the original code and work to the migration of CEVA-X framework notably, have really realized the whole language C (all-in-C) of CEVA-X1643 Programming. ... CEVA-Toolbox is including employing the optimizing device (Application Optimizer) The tool, can let employ developers to totally develop the software easily with language C, thus save the time of developing, save handwritten ...
32 Keywords in C Programming Language | Learn C Programming: 32 Keywords in C Programming Language. Tags / Keywords : | Tokens : Keywords. Keywords : Keywords are those words whose ... Facebook Badge. C Programming Fan Page · Promote Your Page Too. Feedjit. MyFreeCopyright.com Registered & ...
Tutorials Programming in Objective-C 2.0 LiveLessons 6-12 ...: Tutorials Programming in Objective-C 2.0 LiveLessons 6-12 | 3.12GBOur goal is to reach all users fluent in the language they've chosen to learn. Our online video tutorials make ready beginn.
[Free] Turbo C Compiler: Write programs in the C programming ...: [Free] Turbo C Compiler: Write programs in the C programming language. Fancy writing a computer program in the C programming language? The Turbo C 2.01 compiler has been restored to the Free C/C++ Compilers and Interpreters page. ...
Objective-C for Absolute Beginners: iPhone and Mac Programming ...: Tags: Apress, c programming language, carnegie mellon university, com, Development, fundamentals of computer programming, iOSand, iPad, iPhone, ISBN, mac os x, mac programming, object oriented programming, Objective-C for Absolute ...
Monitoring Video & Audio feeds - C Board: Is there a particular programming language that would allow monitoring of multiple video/audio feeds from different IP addresses, allowing the user to.
reverse string - C Board: C Board > General Programming Boards > C Programming. reverse string. User Name, Remember Me? Password .... If programming is like cooking, a programming language is an oven. Last edited by maxorator; 08-25-2010 at 03:55 PM. ...
C programming language most popular « Bits and thoughts: Good news for C programmers: The April 2010 update of the TIOBE index shows that C is the most popular programming language. With about 18% it is close to Java, but 0.007% ahead. Of course, there is criticism of how to measure language ...
8051 Tutorial 3: I/O Port Programming in C — Volts and Bytes: Therefore, it is recommended that the reader is familiar or has basic knowledge about C programming language and electronics circuit analysis. I am going to use Atmel's AT89C2051 as an example for the 8051 microcontroller and the C ...
BMP file format and The C Programming Language – Part 1 | Emil's Blog: BMP file format and The C Programming Language – Part 1. Posted on 09/09/2010 by Emil Refn. In this post i am going to show how to read in a 24 bit BMP, and convert it to greyscale, and save it back out. ...