intN_t(3type) intN_t(3type)
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 ap-
propriate 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 <int-
types.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)
Linux man-pages 6.7 2023-10-31 intN_t(3type)
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