stdint.h

The stdint.h header defines integer types, limits of specified width integer types, limits of other integer types, and macros for integer constant expressions.

Note: For the exact width integer types, minimum-width integer types, limits of specified width integer types, and exact width integer constants, bit sizes N with the values 8, 16, 32, and 64 are supported.

Requirement: Use of the bit size 64 and greatest-width integer types or macros require LP64 or the long long data type to be available.

Integer types

The following exact width integer types are defined.

intN_t
uintN_t

The following minimum-width integer types are defined.

int_leastN_t
uint_leastN_t

The following fastest minimum-width integer types are defined. These types are the fastest to operate with among all integer types that have at least the specified width.

int_fastN_t
uint_fastN_t

The following greatest-width integer types are defined. These types hold the value of any signed/unsigned integer type.

Note: Requires long long to be available.

intmax_t
uintmax_t

The following integer types capable of holding object pointers are defined.

intptr_t
uintptr_t

Object-like macros for limits of integer types:

Macros for limits of exact width integer types.

INTN_MAX
INTN_MIN
UINTN_MAX

Macros for limits of minimum width integer types.

INT_LEASTN_MAX
INT_LEASTN_MIN
UINT_LEASTN_MAX

Macros for limits of fastest minimum width integer types.

INT_FASTN_MAX
INT_FASTN_MIN
UINT_FASTN_MAX

Macros for limits of greatest width integer types.

INTMAX_MAX
INTMAX_MIN
UINTMAX_MAX

Macros for limits of pointer integer types.

INTPTR_MAX
INTPTR_MIN
UINTPTR_MAX

Macros for limits of ptrdiff_t.

PTRDIFF_MAX
PTRDIFF_MIN

Macro for limit of size_t.

SIZE_MAX

Function-like macros for integer constants:

Macros for minimum width integer constants.

INTN_C(value)
UINTN_C(value)

Macros for greatest-width integer constants:

INTMAX_C(value)
UINTMAX_C(value)