DESCRIPTION
This header file defines sets of integer types having specified widths
and corresponding sets of macros.
It also defines macros that specify limits of integer types
corresponding to types defined in other standard headers.
Since not all implementations are required to support all of the
integer sizes defined in this manual page, the proper way to see
if a particular size of an integer is supported on the current
implementation is to test the symbol that defines its maximum value.
For example, if
#ifdef UINT64_MAX
tests false, then that implementation does not support 64-bit
unsigned signed integers.
This header file defines the following integer data types for 8,
16, 32, and 64 bits.
- intmax_t
largest signed integer data type supported by implementation
- int8_t
8-bit signed integer
- int16_t
16-bit signed integer
- int32_t
32-bit signed integer
- int64_t
64-bit signed integer
- uintmax_t
largest unsigned integer data type supported by implementation
- uint8_t
8-bit unsigned integer
- uint16_t
16-bit unsigned integer
- uint32_t
32-bit unsigned integer
- uint64_t
64-bit unsigned integer
The following two data types are signed and unsigned integer data
types that are large enough to hold a pointer.
A pointer can be moved to or from these data types without corruption.
- intptr_t
signed integer type that is large enough to hold a pointer
- uintptr_t
unsigned integer type that is large enough to hold a pointer
This header file defines the following integer data types for determining
the most efficient data types to use for integer values on a
particular implementation.
- intfast_t
most efficient signed integer data type supported by implementation
- int_fast8_t
most efficient signed integer of at least 8 bits
- int_fast16_t
most efficient signed integer of at least 16 bits
- int_fast32_t
most efficient signed integer of at least 32 bits
- int_fast64_t
most efficient signed integer of at least 64 bits
- uintfast_t
most efficient unsigned integer data type supported by implementation
- uint_fast8_t
most efficient unsigned integer of at least 8 bits
- uint_fast16_t
most efficient unsigned integer of at least 16 bits
- uint_fast32_t
most efficient unsigned integer of at least 32 bits
- uint_fast64_t
most efficient unsigned integer of at least 64 bits
This header file defines the following integer data types for compatibility
with systems that do not fit the 16-bit or 32-bit word size model.
These data types define the signed and unsigned integers of at
least 8, 16, 32, and 64 bits.
- int_least8_t
smallest signed integer of at least 8 bits
- int_least16_t
smallest signed integer of at least 16 bits
- int_least32_t
smallest signed integer of at least 32 bits
- int_least64_t
smallest signed integer of at least 64 bits
- uint_least8_t
smallest unsigned integer of at least 8 bits
- uint_least16_t
smallest unsigned integer of at least 16 bits
- uint_least32_t
smallest unsigned integer of at least 32 bits
- uint_least64_t
smallest unsigned integer of at least 64 bits
The following macros define the minimum and maximum values that can
be stored in the above data types.
- INTMAX_MIN
minimum value that can be stored in the largest integer data type
- INTMAX_MAX
maximum value that can be stored in the largest signed integer data type
- UINTMAX_MAX
maximum value that can be stored in the largest unsigned integer data type
- INTFAST_MIN
minimum value that can be stored in the most efficient integer data type
- INTFAST_MAX
maximum value that can be stored in the most efficient signed integer data type
- UINTFAST_MAX
maximum value that can be stored in the most efficient unsigned
integer data type
- INT8_MIN
minimum value that can be stored in an
int8_t
data type
- INT16_MIN
minimum value that can be stored in an
int16_t
data type
- INT32_MIN
minimum value that can be stored in an
int32_t
data type
- INT64_MIN
minimum value that can be stored in an
int64_t
data type
- INT8_MAX
maximum value that can be stored in an
int8_t
data type
- INT16_MAX
maximum value that can be stored in an
int16_t
data type
- INT32_MAX
maximum value that can be stored in an
int32_t
data type
- INT64_MAX
maximum value that can be stored in an
int64_t
data type
- UINT8_MAX
maximum value that can be stored in an
uint8_t
data type
- UINT16_MAX
maximum value that can be stored in an
uint16_t
data type
- UINT32_MAX
maximum value that can be stored in an
uint32_t
data type
- UINT64_MAX
maximum value that can be stored in an
uint64_t
data type"
- INT_FAST8_MIN
minimum value that can be stored in an
int_fast8_t
data type
- INT_FAST16_MIN
minimum value that can be stored in an
int_fast16_t
data type"
- INT_FAST32_MIN
minimum value that can be stored in an
int_fast32_t
data type
- INT_FAST64_MIN
minimum value that can be stored in an
int_fast64_t
data type
- INT_FAST8_MAX
maximum value that can be stored in an
int_fast8_t
data type
- INT_FAST16_MAX
maximum value that can be stored in an
int_fast16_t
data type
- INT_FAST32_MAX
maximum value that can be stored in an
int_fast32_t
data type
- INT_FAST64_MAX
maximum value that can be stored in an
int_fast64_t
data type
- INT_LEAST8_MIN
minimum value that can be stored in an
int_least8_t
data type
- INT_LEAST16_MIN
minimum value that can be stored in an
int_least16_t
data type
- INT_LEAST32_MIN
minimum value that can be stored in an
int_least_32_t
data type
- INT_LEAST64_MIN
minimum value that can be stored in an
int_least_64_t
data type
- INT_LEAST8_MAX
maximum value that can be stored in an
int_least8_t
data type
- INT_LEAST16_MAX
maximum value that can be stored in an
int_least16_t
data type
- INT_LEAST32_MAX
maximum value that can be stored in an
int_least_32_t
data type
- INT_LEAST64_MAX
maximum value that can be stored in an
int_least_64_t
data type
The following macros specify the maximum and minimum limits of
integer types corresponding to types defined in other standard headers.
All these values are implementation defined.
- PTRDIFF_MIN
minimum value that can be stored in
ptrdiff_t
data type
- PTRDIFF_MAX
maximum value that can be stored in
ptrdiff_t
data type
- SIG_ATOMIC_MIN
minimum value that can be stored in
sig_atomic_t
data type
- SIG_ATOMIC_MAX
maximum value that can be stored in
sig_atomic_t
data type
- SIZE_MAX
maximum value that can be stored in
size_t
data type
- WCHAR_MIN
minimum value that can be stored in
wchar_t
data type
- WCHAR_MAX
maximum value that can be stored in
wchar_t
data type
- WINT_MIN
minimum value that can be stored in
wint_t
data type
- WINT_MAX
maximum value that can be stored in
wint_t
data type
The following macros expand to integer constant expressions
suitable for initializing objects that have integer types
corresponding to types defined in
<stdint.h>
header.
Macros For Minimum-Width Integer Constant Expressions
The macro
INTN_C(value)
expands to an integer constant expression corresponding to the type
int_leastN_t.
The macro
UINTN_C(value)
expands to an integer constant expression corresponding to the type
uint_leastN_t.
For example, if
uint_least64_t
is a name for the type
unsigned long long,
then
UINT64_C(0x123)
might expand to the integer constant
0x123ULL.
Macros For Greatest-Width Integer Constant Expressions
The following macro expands to an integer constant expression having
the value specified by its argument and the type
intmax_t: INTMAX_C(value)
The following macro expands to an integer constant expression having the
value specified by its argument and the type
uintmax_t: UINTMAX_C(value).
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