Fixed width integer types (since C99)
Types
Defined in header
<stdint.h> | |
int8_tint16_tint32_tint64_t (optional) |
signed integer type with width of exactly 8, 16, 32 and 64 bits respectively with no padding bits and using 2's complement for negative values (provided if and only if the implementation directly supports the type) (typedef) |
int_fast8_tint_fast16_tint_fast32_tint_fast64_t |
fastest signed integer type with width of at least 8, 16, 32 and 64 bits respectively (typedef) |
int_least8_tint_least16_tint_least32_tint_least64_t |
smallest signed integer type with width of at least 8, 16, 32 and 64 bits respectively (typedef) |
intmax_t |
maximum-width signed integer type (typedef) |
intptr_t |
signed integer type capable of holding a pointer (This type need not be available) (typedef) |
uint8_tuint16_tuint32_tuint64_t (optional) |
unsigned integer type with width of exactly 8, 16, 32 and 64 bits respectively (provided if and only if the implementation directly supports the type) (typedef) |
uint_fast8_tuint_fast16_tuint_fast32_tuint_fast64_t |
fastest unsigned integer type with width of at least 8, 16, 32 and 64 bits respectively (typedef) |
uint_least8_tuint_least16_tuint_least32_tuint_least64_t |
smallest unsigned integer type with width of at least 8, 16, 32 and 64 bits respectively (typedef) |
uintmax_t |
maximum-width unsigned integer type (typedef) |
uintptr_t |
unsigned integer type capable of holding a pointer (This type need not be available) (typedef) |
The implementation may define typedef names intN_t
, int_fastN_t
, int_leastN_t
, uintN_t
, uint_fastN_t
, and uint_leastN_t
when N is not 8, 16, 32 or 64. Typedef names of the form intN_t
may only be defined if the implementation supports an integer type of that width with no padding. Thus, uint24_t denotes an unsigned integer type with a width of exactly 24 bits.
Each of the macros listed in below is defined if and only if the implementation defines the corresponding typedef name. The macros INTN_C
and UINTN_C
correspond to the typedef names int_leastN_t
and uint_leastN_t
, respectively.
Macro constants
Defined in header
<stdint.h> | |
Signed integers : width | |
INT8_WIDTHINT16_WIDTHINT32_WIDTHINT64_WIDTH (C23)(optional) |
bit width of an object of type int8_t, int16_t, int32_t, int64_t (exactly 8, 16, 32, 64) (macro constant) |
INT_FAST8_WIDTHINT_FAST16_WIDTHINT_FAST32_WIDTHINT_FAST64_WIDTH (C23) |
bit width of an object of type int_fast8_t, int_fast16_t, int_fast32_t, int_fast64_t (macro constant) |
INT_LEAST8_WIDTHINT_LEAST16_WIDTHINT_LEAST32_WIDTHINT_LEAST64_WIDTH (C23) |
bit width of an object of type int_least8_t, int_least16_t, int_least32_t, int_least64_t (macro constant) |
INTPTR_WIDTH (C23)(optional) |
bit width of an object of type intptr_t (macro constant) |
INTMAX_WIDTH (C23) |
bit width of an object of type intmax_t (macro constant) |
Signed integers : minimum value | |
INT8_MININT16_MININT32_MININT64_MIN (optional) |
minimum value of an object of type int8_t, int16_t, int32_t, int64_t (macro constant) |
INT_FAST8_MININT_FAST16_MININT_FAST32_MININT_FAST64_MIN |
minimum value of an object of type int_fast8_t, int_fast16_t, int_fast32_t, int_fast64_t (macro constant) |
INT_LEAST8_MININT_LEAST16_MININT_LEAST32_MININT_LEAST64_MIN |
minimum value of an object of type int_least8_t, int_least16_t, int_least32_t, int_least64_t (macro constant) |
INTPTR_MIN (optional) |
minimum value of an object of type intptr_t (macro constant) |
INTMAX_MIN |
minimum value of an object of type intmax_t (macro constant) |
Signed integers : maximum value | |
INT8_MAXINT16_MAXINT32_MAXINT64_MAX (optional) |
maximum value of an object of type int8_t, int16_t, int32_t, int64_t (macro constant) |
INT_FAST8_MAXINT_FAST16_MAXINT_FAST32_MAXINT_FAST64_MAX |
maximum value of an object of type int_fast8_t, int_fast16_t, int_fast32_t, int_fast64_t (macro constant) |
INT_LEAST8_MAXINT_LEAST16_MAXINT_LEAST32_MAXINT_LEAST64_MAX |
maximum value of an object of type int_least8_t, int_least16_t, int_least32_t, int_least64_t (macro constant) |
INTPTR_MAX (optional) |
maximum value of an object of type intptr_t (macro constant) |
INTMAX_MAX |
maximum value of an object of type intmax_t (macro constant) |
Unsigned integers : width | |
UINT8_WIDTHUINT16_WIDTHUINT32_WIDTHUINT64_WIDTH (C23)(optional) |
bit width of an object of type uint8_t, uint16_t, uint32_t, uint64_t (exactly 8, 16, 32, 64) (macro constant) |
UINT_FAST8_WIDTHUINT_FAST16_WIDTHUINT_FAST32_WIDTHUINT_FAST64_WIDTH (C23) |
bit width of an object of type uint_fast8_t, uint_fast16_t, uint_fast32_t, uint_fast64_t (macro constant) |
UINT_LEAST8_WIDTHUINT_LEAST16_WIDTHUINT_LEAST32_WIDTHUINT_LEAST64_WIDTH (C23) |
bit width of an object of type uint_least8_t, uint_least16_t, uint_least32_t, uint_least64_t (macro constant) |
UINTPTR_WIDTH (C23)(optional) |
bit width of an object of type uintptr_t (macro constant) |
UINTMAX_WIDTH (C23) |
bit width of an object of type uintmax_t (macro constant) |
Unsigned integers : maximum value | |
UINT8_MAXUINT16_MAXUINT32_MAXUINT64_MAX (optional) |
maximum value of an object of type uint8_t, uint16_t, uint32_t, uint64_t (macro constant) |
UINT_FAST8_MAXUINT_FAST16_MAXUINT_FAST32_MAXUINT_FAST64_MAX |
maximum value of an object of type uint_fast8_t, uint_fast16_t, uint_fast32_t, uint_fast64_t (macro constant) |
UINT_LEAST8_MAXUINT_LEAST16_MAXUINT_LEAST32_MAXUINT_LEAST64_MAX |
maximum value of an object of type uint_least8_t, uint_least16_t, uint_least32_t, uint_least64_t (macro constant) |
UINTPTR_MAX (optional) |
maximum value of an object of type uintptr_t (macro constant) |
UINTMAX_MAX |
maximum value of an object of type uintmax_t (macro constant) |
Function macros for minimum-width integer constants
Defined in header
<stdint.h> | |
INT8_CINT16_CINT32_CINT64_C |
expands to an integer constant expression having the value specified by its argument and whose type is the promoted type of int_least8_t, int_least16_t, int_least32_t, int_least64_t respectively (function macro) |
INTMAX_C |
expands to an integer constant expression having the value specified by its argument and the type intmax_t (function macro) |
UINT8_CUINT16_CUINT32_CUINT64_C |
expands to an integer constant expression having the value specified by its argument and whose type is the promoted type of uint_least8_t, uint_least16_t, uint_least32_t, uint_least64_t respectively (function macro) |
UINTMAX_C |
expands to an integer constant expression having the value specified by its argument and the type uintmax_t (function macro) |
#include <stdint.h> UINT64_C(0x123) // might expand to 0x123ULL or 0x123UL
Format macro constants
Defined in header
<inttypes.h> |
Format constants for the fprintf family of functions
Each of the PRI
macros listed here is defined if and only if the implementation defines the corresponding typedef name.
Equivalent for int or unsigned int |
Description | Macros for data types | ||||
---|---|---|---|---|---|---|
[u]intx_t |
[u]int_leastx_t |
[u]int_fastx_t |
[u]intmax_t |
[u]intptr_t | ||
d
|
output of a signed decimal integer value | PRIdx | PRIdLEASTx | PRIdFASTx | PRIdMAX | PRIdPTR |
i
|
PRIix | PRIiLEASTx | PRIiFASTx | PRIiMAX | PRIiPTR | |
u
|
output of an unsigned decimal integer value | PRIux | PRIuLEASTx | PRIuFASTx | PRIuMAX | PRIuPTR |
o
|
output of an unsigned octal integer value | PRIox | PRIoLEASTx | PRIoFASTx | PRIoMAX | PRIoPTR |
x
|
output of an unsigned lowercase hexadecimal integer value | PRIxx | PRIxLEASTx | PRIxFASTx | PRIxMAX | PRIxPTR |
X
|
output of an unsigned uppercase hexadecimal integer value | PRIXx | PRIXLEASTx | PRIXFASTx | PRIXMAX | PRIXPTR |
Format constants for the fscanf family of functions
Each of the SCN
macros listed in here is defined if and only if the implementation defines the corresponding typedef name and has a suitable fscanf length modifier for the type.
Equivalent for int or unsigned int |
Description | Macros for data types | ||||
---|---|---|---|---|---|---|
[u]intx_t |
[u]int_leastx_t |
[u]int_fastx_t |
[u]intmax_t |
[u]intptr_t | ||
d
|
input of a signed decimal integer value | SCNdx | SCNdLEASTx | SCNdFASTx | SCNdMAX | SCNdPTR |
i
|
input of a signed integer value (base is determined by the first characters parsed) | SCNix | SCNiLEASTx | SCNiFASTx | SCNiMAX | SCNiPTR |
u
|
input of an unsigned decimal integer value | SCNux | SCNuLEASTx | SCNuFASTx | SCNuMAX | SCNuPTR |
o
|
input of an unsigned octal integer value | SCNox | SCNoLEASTx | SCNoFASTx | SCNoMAX | SCNoPTR |
x
|
input of an unsigned hexadecimal integer value | SCNxx | SCNxLEASTx | SCNxFASTx | SCNxMAX | SCNxPTR |
Example
Possible output:
8 lld -9223372036854775808 +9223372036854775807 +7
References
- C17 standard (ISO/IEC 9899:2018):
- 7.8.1 Macros for format specifiers (p: 158-159)
- 7.18 Integer types <stdint.h> (p: 212-216)
- C11 standard (ISO/IEC 9899:2011):
- 7.8.1 Macros for format specifiers (p: 217-218)
- 7.18 Integer types <stdint.h> (p: 289-295)
- C99 standard (ISO/IEC 9899:1999):
- 7.8.1 Macros for format specifiers (p: 198-199)
- 7.18 Integer types <stdint.h> (p: 255-261)