History of C

 

C

Language

headers

Type support

Dynamic memory management

Error handling

Program utilities

Variadic function support

Date and time utilities

Strings library

Algorithms

Numerics

Input/output support

Localization support

Thread support (C11)

Atomic operations (C11)

Technical Specifications

 

C language

ASCII chart

Basic concepts

translation phases

comment

identifier

scope

lifetime

name space

type

arithmetic types

object

main function

memory model

Keywords

Preprocessor

Statements

Expressions

Initialization

Declarations

Functions

Miscellaneous

history of C

Technical Specifications

 

Early C

• 1969: B created, based on BCPL, to replace PDP-7 assembler as the system programming language for Unix

• added operators ++, --, compound assignment, remained a typeless language like BCPL

• 1971: NB ("new B") created when porting B to PDP-11

• types (int, char, arrays and pointers), array-to-pointer conversion, compilation to machine code

• 1972: Language renamed to C

• structs, operators && and ||, preprocessor, portable I/O

• 1973: Unix re-written in C

• unsigned, long, unions, enumerations, increased type safety

• 1978: The C Programming Language, 1st edition

Standard C

• 1983: ANSI established X3J11 committee
• 1988: The C Programming Language, 2nd edition
• 1989: C89, the ANSI C standard published

1. codified existing practices
2. new features: volatile, enum, signed, void, locales
3. From C++: const, function prototypes

• 1990: C90, the ANSI C standard accepted as ISO/IEC 9899-1990
• 1995: C95 (ISO/IEC 9899 AM1) (online store)

1. multibyte character support (wchar_t and all wide and multibyte character functions, wchar.h, wctype.h, and those added to existing headers and corresponding changes to stream I/O, etc)
2. digraphs, iso646.h,

• 1995: Technical corrigendum 1 (ISO/IEC 9899 TCOR1)

• 44 small changes

• 1996: Technical corrigendum 2 (ISO/IEC 9899 TCOR2)

• 24 small changes

• 1999: C99 (ISO/IEC 9899:1999)

1. new features: bool, long long, stdint.h, inttypes.h, restrict, compound literals, variable length arrays, flexible array members, designated initializers, fenv.h, variadic macros, complex numbers, __func__, hexadecimal floating point format (%a), monetary formatting in lconv, isblank, concatenation of narrow and wide string literals, trailing comma in enumerations, empty arguments in function-like macros, STDC_* pragmas, va_copy, null return of tmpnam, null pointer in setvbuf, hh and ll lengthspecifiers in printf, snprintf, _Exit, tgmath.h, POSIX-like strftime specifiers
2. from C++: inline, mix declarations and code, declarations in the init clause of the for loop, // comments, universal character names in source code
3. removed implicit functions and implicit int

• 2001: Technical corrigendum 1 (ISO/IEC 9899:1999/Cor.1:2001(E))

• 11 defects fixed

• 2004: Technical corrigendum 2 (ISO/IEC 9899:1999/Cor.2:2004(E))
• 2004: Unicode TR (ISO/IEC TR 19769:2004) (ISO store) (November 7, 2003 draft)
• 2007: Technical corrigendum 3 (ISO/IEC 9899:1999/Cor.3:2007(E)) (September 7, 2007 draft)

• deprecated gets

• 2007: Bounds-checking interfaces TR (ISO/IEC TR 24731-1:2007) (ISO store) (March 28, 2007 draft)
• 2008: Embedded TR (ISO/IEC TR 18037:2008) (ISO store) (September 24, 2003 draft)
• 2009: Decimal floating-point TR (ISO/IEC TR 24732:2009) (ISO store) (July 5, 2007 draft)
• 2009: Mathematical special functions TR (ISO/IEC TR 24747:2009) (ISO store) (August 2, 2006 draft)
• 2010: Dynamic allocations functions TR (ISO/IEC TR 24731-2:2010) (ISO store) (August 15, 2007 draft)
• 2011: C11 (ISO/IEC 9899:2011) (ISO store) (ANSI store) (April 12, 2011 draft)

1. thread-aware memory model, stdatomic.h, threads.h, type-generic functions, alignas/alignof, noreturn, static assert, analyzability extensions, extensions to complex and imaginary types, anonymous structures and unions, exclusive file open mode. quick_exit
2. removed gets
3. from Bounds-checking interfaces TR: bounds-checking interfaces,
4. from Unicode TR: char16_t, char32_t, and uchar.h

• 2012: Technical corrigendum 1 (ISO/IEC 9899:2011/Cor 1:2012) (ISO store)

• 2 minor bug fixes

• 2013: Secure Coding Rules TS (ISO/IEC TS 17961:2013) (ISO store) (June 26, 2012)
• 2014: FP TS part 1: Binary floating-point arithmetic (ISO/IEC TS 18661-1:2014) (ISO store) (2013 draft )

1. provides changes to C11 (mostly to Annex F) that cover all basic requirements and some recommendations of IEC 60559:2011 (C11 was built on IEC 60559:1989)

• 2015: FP TS part 2: Decimal floating-point arithmetic (ISO/IEC TS 18661-2:2015) (ISO store) (2015 draft)

1. provides changes to C11 to support all the requirements, plus some basic recommendations, of IEC 60559:2011 for decimal floating-point arithmetic. This supersedes ISO/IEC TR 24732:2009.

• 2015: FP TS part 3: Interchange and extended types (ISO/IEC TS 18661-3:2015) (ISO store) (2015 draft)

1. provides changes to C11 to support the recommendations of IEC 60559:2011 for extended floating‐point formats and the interchange formats, both arithmetic and non-arithmetic.

• 2015: FP TS part 4: Supplementary functions (ISO/IEC TS 18661-4:2015) (ISO store) (2015 draft)

1. provides changes to C11 to support all mathematical operations recommended by IEC 60559:2011, including trigonometry in π units, inverse square root, compounded interest, etc.

Future development

• FP TS part 5: supplementary attributes. (Draft n2004 2016-03-07)
• Parallelism TS (Draft n2017 2016-03-10)
• Transactional Memory TS (Draft n1961 2015-09-23)
• C2x Next C language standard revision

• List of C11 defect reports: n1986 (october 2015)
• List of issues that were not granted DR status: n1972 (october 2015)

See also

C++ documentation for History of C++

References

• The Development of the C Language by Dennis M. Ritchie
• Rationale for the C99 standard