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Difference between revisions of "c/standard library"
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Standard C provides 29 standard headers. The headers may be included in any order. The headers may also be included more than once - the effect of that is as if it was only included once. All standard C functions have external linkage. | Standard C provides 29 standard headers. The headers may be included in any order. The headers may also be included more than once - the effect of that is as if it was only included once. All standard C functions have external linkage. | ||
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| − | + | * {{c header|assert.h}} | |
| − | + | * {{c header|complex.h}} | |
| − | + | * {{c header|ctype.h}} | |
| − | + | * {{c header|errno.h}} | |
| − | + | * {{c header|fenv.h}} | |
| − | + | * {{c header|float.h}} | |
| − | + | * {{c header|inttypes.h}} | |
| − | + | * {{c header|iso646.h}} | |
| − | + | * {{c header|limits.h}} | |
| − | + | * {{c header|locale.h}} | |
| − | + | * {{c header|math.h}} | |
| − | + | * {{c header|setjmp.h}} | |
| − | + | * {{c header|signal.h}} | |
| − | + | * {{c header|stdalign.h}} | |
| − | + | * {{c header|stdarg.h}} | |
| − | + | * {{c header|stdatomic.h}} | |
| − | + | * {{c header|stdbool.h}} | |
| − | + | * {{c header|stddef.h}} | |
| − | + | * {{c header|stdint.h}} | |
| − | + | * {{c header|stdio.h}} | |
| − | + | * {{c header|stdlib.h}} | |
| − | + | * {{c header|stdnoreturn.h}} | |
| − | + | * {{c header|string.h}} | |
| − | + | * {{c header|tgmath.h}} | |
| − | + | * {{c header|threads.h}} | |
| − | + | * {{c header|time.h}} | |
| − | + | * {{c header|uchar.h}} | |
| − | + | * {{c header|wchar.h}} | |
| − | + | * {{c header|wctype.h}} | |
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== Optional headers == | == Optional headers == | ||
Latest revision as of 14:28, 9 March 2016
The C standard library is a standardized collection of headers and library functions for the C programming language. The library provides a set of commonly used macros, type definitions, and functions to perform common tasks such as string handling, input/output processing, memory allocation, math computations, thread management, and various other common services.
Standard Headers[edit]
Related functions, necessary types to use those functions and related macros are grouped into headers. Collectively, they are known as the standard headers.
Standard C provides 29 standard headers. The headers may be included in any order. The headers may also be included more than once - the effect of that is as if it was only included once. All standard C functions have external linkage.
- <assert.h>
- <complex.h>
- <ctype.h>
- <errno.h>
- <fenv.h>
- <float.h>
- <inttypes.h>
- <iso646.h>
- <limits.h>
- <locale.h>
- <math.h>
- <setjmp.h>
- <signal.h>
- <stdalign.h>
- <stdarg.h>
- <stdatomic.h>
- <stdbool.h>
- <stddef.h>
- <stdint.h>
- <stdio.h>
- <stdlib.h>
- <stdnoreturn.h>
- <string.h>
- <tgmath.h>
- <threads.h>
- <time.h>
- <uchar.h>
- <wchar.h>
- <wctype.h>
Optional headers[edit]
3 of the 29 standard headers are optional:
While implementations are encouraged to support those headers, they are not required to.
Detailed description[edit]
| Header Name | Since | Description |
|---|---|---|
| <assert.h> | C89 | Provides a set of assertion macros used in assisting with debugging and detecting logic errors. |
| <complex.h> | C99 | Provides a set of functions used to manipulate complex numbers. |
| <ctype.h> | C89 | Provides a set of functions used for classifying characters. |
| <errno.h> | C89 | Provides a set of predefined values for errno. |
| <fenv.h> | C99 | Provides a set of functions for controlling the floating-point environment. |
| <float.h> | C89 | Provides a set of macros defining the implementation of the floating-point environment. |
| <inttypes.h> | C99 | Provides a set of exact width integer types. |
| <iso646.h> | NA1 | Provides a set of macros that implement an alternative way of expressing various C operators |
| <limits.h> | C89 | Provides a set of macros specifying the implementation-specific limits of the integer types. |
| <locale.h> | C89 | Provides a set of functions localization functions |
| <math.h> | C89 | Provides a set of common mathematical functions. |
| <setjmp.h> | C89 | Provides macros to perform non-local jump operators. |
| <signal.h> | C89 | Provides a set of signal handling functions. |
| <stdalign.h> | C11 | Provides a set of macros for working with object alignments. |
| <stdarg.h> | C89 | Provides a set of macros for working with variadic functions |
| <stdatomic.h> | C11 | Provides a set of functions for performing atomic operations on data. |
| <stdbool.h> | C99 | Provides boolean macros. |
| <stddef.h> | C89 | Provides a set of commonly used type definitions within the standard library. |
| <stdint.h> | C99 | Provides a set of exact width integer types. |
| <stdio.h> | C89 | Provides a set of standard input/output processing functions. |
| <stdlib.h> | C89 | Provides core library functions such as memory management and random number generation. |
| <stdnoreturn.h> | C11 | Provides a macro for specifying non-returning functions. |
| <string.h> | C89 | string handling functions. |
| <tgmath.h> | C99 | Provides a set of type-generic math functions. |
| <threads.h> | C11 | Provides a set of thread management functions. |
| <time.h> | C89 | Provides a set of date and time handling functions. |
| <uchar.h> | C11 | Provides a set of Unicode character manipulation functions. |
| <wchar.h> | NA1 | string handling functions. |
| <wctype.h> | NA1 | Provides a set of functions used for classifying wide characters. |
Embedded C[edit]
- Main article: Embedded C
Embedded C introduced two optional headers <stdfix.h> and <iohw.h>. The headers not formally part of the standard library.