STDINT(7) BSD Miscellaneous Information Manual STDINT(7)NAMEstdint — standard integer types
SYNOPSIS
#include <stdint.h>
DESCRIPTION
The <stdint.h> header provides source-portable integer types of a spe‐
cific size, smallest memory footprint with a minimum size, fastest access
speed with a minimum size, largest integer size, and those capable of
storing pointers.
The types int8_t, int16_t, int32_t, and int64_t provide a signed integer
type of width 8, 16, 32, or 64 bits, respectively. The types uint8_t,
uint16_t, uint32_t, and uint64_t provide an unsigned integer type of
width 8, 16, 32, or 64 bits, respectively. These integer types should be
used when a specific size is required.
The types int_fast8_t, int_fast16_t, int_fast32_t, and int_fast64_t pro‐
vide the fastest signed integer type with a width of at least 8, 16, 32,
or 64 bits, respectively. The types uint_fast8_t, uint_fast16_t,
uint_fast32_t, and uint_fast64_t provide the fastest unsigned integer
type with a width of at least 8, 16, 32, or 64 bits, respectively. These
types should be used when access speed is paramount, and when a specific
size is not required.
The types int_least8_t, int_least16_t, int_least32_t, and int_least64_t
provide the smallest memory footprint signed integer type with a width of
at least 8, 16, 32, or 64 bits, respectively. The types uint_least8_t,
uint_least16_t, uint_least32_t, and uint_least64_t provide the smallest
memory footprint unsigned integer type with a width of at least 8, 16,
32, or 64 bits, respectively. These types should be used when memory
storage is of concern, and when a specific size is not required.
The type intmax_t provides a signed integer type large enough to hold any
other signed integer. The type uintmax_t provides an unsigned integer
type large enough to hold any other unsigned integer. These types are
generally the largest signed and unsigned integer types available on a
specific architecture.
The type intptr_t provides a signed integer type with the ability to hold
a pointer to void, that can later be converted back to a pointer to void.
and the result will compare equal to the original pointer.
The type uintptr_t provides an unsigned integer type with the ability to
hold a pointer to void, that can later be converted back to a pointer to
void. and the result will compare equal to the original pointer.
The INTX_C() expands to an integer constant expression corresponding to
the type int_leastX_t. The UINTX_C() expands to an integer constant
expression corresponding to the type uint_leastX_t. For example,
UINT64_C(0x123) expands to integer constant 0x123ULL.
The INTMAX_C() macro expands to an integer constant expression having the
value specified by its argument and the type intmax_t. The UINTMAX_C()
macro expands to an integer constant expression having the value speci‐
fied by its argument and the type uintmax_t.
STANDARDS
The <stdint.h> header conforms to ISO/IEC 9899:1999 (“ISO C99”) and IEEE
Std 1003.1-2001 (“POSIX.1”).
BSD March 22, 2009 BSD
