uintN_t.3type

intN_t

NAME
LIBRARY
SYNOPSIS
DESCRIPTION
STANDARDS
HISTORY
NOTES
SEE ALSO

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NAME

intN_t, int8_t, int16_t, int32_t, int64_t, uintN_t, uint8_t, uint16_t, uint32_t, uint64_t − fixed-width basic integer types

LIBRARY

Standard C library (libc)

SYNOPSIS

#include <stdint.h>

typedef /* … */ int8_t;
typedef /* … */ int16_t;
typedef /* … */ int32_t;
typedef /* … */ int64_t;

typedef /* … */ uint8_t;
typedef /* … */ uint16_t;
typedef /* … */ uint32_t;
typedef /* … */ uint64_t;

#define INT8_WIDTH 8
#define INT16_WIDTH 16
#define INT32_WIDTH 32
#define INT64_WIDTH 64

#define UINT8_WIDTH 8
#define UINT16_WIDTH 16
#define UINT32_WIDTH 32
#define UINT64_WIDTH 64

#define INT8_MAX /* 2**(INT8_WIDTH - 1) - 1 */ **
#define INT16_MAX** /* 2**(INT16_WIDTH - 1) - 1 */ **
#define INT32_MAX** /* 2**(INT32_WIDTH - 1) - 1 */ **
#define INT64_MAX** /* 2**(INT64_WIDTH - 1) - 1 */

#define INT8_MIN /* - 2**(INT8_WIDTH - 1) */ **
#define INT16_MIN** /* - 2**(INT16_WIDTH - 1) */ **
#define INT32_MIN** /* - 2**(INT32_WIDTH - 1) */ **
#define INT64_MIN** /* - 2**(INT64_WIDTH - 1) */

#define UINT8_MAX /* 2**INT8_WIDTH - 1 */ **
#define UINT16_MAX** /* 2**INT16_WIDTH - 1 */ **
#define UINT32_MAX** /* 2**INT32_WIDTH - 1 */ **
#define UINT64_MAX** /* 2**INT64_WIDTH - 1 */

#define INT8_C(c) c ## /* … */ **
#define INT16_C(c)** c ## /* … */ **
#define INT32_C(c)** c ## /* … */ **
#define INT64_C(c)** c ## /* … */

#define UINT8_C(c) c ## /* … */ **
#define UINT16_C(c)** c ## /* … */ **
#define UINT32_C(c)** c ## /* … */ **
#define UINT64_C(c)** c ## /* … */

DESCRIPTION

intN*_t* are signed integer types of a fixed width of exactly N bits, N being the value specified in its type name. They are be capable of storing values in the range [INTN**_MIN**, INTN**_MAX**], substituting N by the appropriate number.

uintN*_t* are unsigned integer types of a fixed width of exactly N bits, N being the value specified in its type name. They are capable of storing values in the range [0, UINTN**_MAX**], substituting N by the appropriate number.

According to POSIX, [u]int8_t, [u]int16_t, and [u]int32_t are required; [u]int64_t are only required in implementations that provide integer types with width 64; and all other types of this form are optional.

The macros [U]INTN**_WIDTH** expand to the width in bits of these types (N).

The macros [U]INTN**_MAX** expand to the maximum value that these types can hold.

The macros INTN**_MIN** expand to the minimum value that these types can hold.

The macros [U]INTN**_C**() expand their argument to an integer constant of type [u]intN*_t*.

The length modifiers for the [u]intN*_t* types for the printf(3) family of functions are expanded by macros of the forms PRIdN, PRIiN, PRIuN, and PRIxN (defined in <inttypes.h>); resulting for example in %“PRId64” or %“PRIi64” for printing int64_t values. The length modifiers for the [u]intN*_t* types for the scanf(3) family of functions are expanded by macros of the forms SCNdN, SCNiN, SCNuN, and SCNxN, (defined in <inttypes.h>); resulting for example in %“SCNu8” or %“SCNx8” for scanning uint8_t values.

STANDARDS

C11, POSIX.1-2008.

HISTORY

C99, POSIX.1-2001.

The [U]INTN**_WIDTH** macros were added in C23.

NOTES

The following header also provides these types: <inttypes.h>. <arpa/inet.h> also provides uint16_t and uint32_t.

SEE ALSO

intmax_t(3type), intptr_t(3type), printf(3)

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