Standard library header <cstdint>

C++

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Headers

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Named requirements

Language support library

Concepts library (C++20)

Diagnostics library

Utilities library

Strings library

Containers library

Algorithms library

Iterators library

Numerics library

Input/output library

Localizations library

Regular expressions library (C++11)

Atomic operations library (C++11)

Thread support library (C++11)

Filesystem library (C++17)

Technical Specifications

Standard Library header files

Language Support
<cstddef> <limits> <climits> <contract>	<cfloat> <cstdint> <new> <version>	<typeinfo> <exception> <initializer_list>	<csignal> <csetjmp> <cstdarg>
Concepts
<concepts>
Diagnostics
<stdexcept>	<cassert>	<cerrno>	<system_error>
General utilities
<utility> <memory> <memory_resource> <scoped_allocator> <compare>	<bitset> <tuple> <optional> <any> <variant>	<type_traits> <ratio> <chrono> <typeindex> <functional>	<ctime> <cstdlib>
Strings
<string> <string_view>	<cctype> <cwctype>	<cwchar> <cuchar>	<cstring> <charconv>
Localization
<locale>	<codecvt>	<clocale>
Containers
<span> <array> <vector>	<deque> <forward_list> <list>	<map> <set> <queue>	<unordered_map> <unordered_set> <stack>
Iterators
<iterator>
Algorithms
<algorithm>	<execution>
Numerics
<complex> <random>	<valarray> <numeric>	<cfenv> <cmath>	<bit>
Input/Output
<iosfwd> <ios> <iomanip> <streambuf>	<istream> <ostream> <iostream>	<sstream> <fstream> <syncstream>	<cstdio> <cinttypes> <strstream>
Regular expressions
<regex>
Filesystem support
<filesystem>
Thread support
<thread> <atomic>	<mutex> <shared_mutex>	<condition_variable> <future>
C compatibility
<ciso646> <cstdalign>	<cstdbool> <ccomplex>	<ctgmath>

This header was originally in the C standard library as <stdint.h>.

This header is part of the type support library, providing fixed width integer types and part of C numeric limits interface.

Types

Defined in header <cstdint>
int8_tint16_tint32_tint64_t (optional)	signed integer type with width of exactly 8, 16, 32 and 64 bits respectively with no padding bits and using 2's complement for negative values (provided only if the implementation directly supports the type) (typedef)
int_fast8_tint_fast16_tint_fast32_tint_fast64_t	fastest signed integer type with width of at least 8, 16, 32 and 64 bits respectively (typedef)
int_least8_tint_least16_tint_least32_tint_least64_t	smallest signed integer type with width of at least 8, 16, 32 and 64 bits respectively (typedef)
intmax_t	maximum width integer type (typedef)
intptr_t (optional)	signed integer type capable of holding a pointer (typedef)
uint8_tuint16_tuint32_tuint64_t (optional)	unsigned integer type with width of exactly 8, 16, 32 and 64 bits respectively (provided only if the implementation directly supports the type) (typedef)
uint_fast8_tuint_fast16_tuint_fast32_tuint_fast64_t	fastest unsigned integer type with width of at least 8, 16, 32 and 64 bits respectively (typedef)
uint_least8_tuint_least16_tuint_least32_tuint_least64_t	smallest unsigned integer type with width of at least 8, 16, 32 and 64 bits respectively (typedef)
uintmax_t	maximum width unsigned integer type (typedef)
uintptr_t (optional)	unsigned integer type capable of holding a pointer (typedef)

Macros

Defined in header <cstdint>
Signed integers: minimum value
INT8_MININT16_MININT32_MININT64_MIN	minimum value of an object of type int8_t, int16_t, int32_t, int64_t (macro constant)
INT_FAST8_MININT_FAST16_MININT_FAST32_MININT_FAST64_MIN	minimum value of an object of type int_fast8_t, int_fast16_t, int_fast32_t, int_fast64_t (macro constant)
INT_LEAST8_MININT_LEAST16_MININT_LEAST32_MININT_LEAST64_MIN	minimum value of an object of type int_least8_t, int_least16_t, int_least32_t, int_least64_t (macro constant)
INTPTR_MIN	minimum value of an object of type intptr_t (macro constant)
INTMAX_MIN	minimum value of an object of type intmax_t (macro constant)
Signed integers: maximum value
INT8_MAXINT16_MAXINT32_MAXINT64_MAX	maximum value of an object of type int8_t, int16_t, int32_t, int64_t (macro constant)
INT_FAST8_MAXINT_FAST16_MAXINT_FAST32_MAXINT_FAST64_MAX	maximum value of an object of type int_fast8_t, int_fast16_t, int_fast32_t, int_fast64_t (macro constant)
INT_LEAST8_MAXINT_LEAST16_MAXINT_LEAST32_MAXINT_LEAST64_MAX	maximum value of an object of type int_least8_t, int_least16_t, int_least32_t, int_least64_t (macro constant)
INTPTR_MAX	maximum value of an object of type intptr_t (macro constant)
INTMAX_MAX	maximum value of an object of type intmax_t (macro constant)
Unsigned integers: maximum value
UINT8_MAXUINT16_MAXUINT32_MAXUINT64_MAX	maximum value of an object of type uint8_t, uint16_t, uint32_t, uint64_t (macro constant)
UINT_FAST8_MAXUINT_FAST16_MAXUINT_FAST32_MAXUINT_FAST64_MAX	maximum value of an object of type uint_fast8_t, uint_fast16_t, uint_fast32_t, uint_fast64_t (macro constant)
UINT_LEAST8_MAXUINT_LEAST16_MAXUINT_LEAST32_MAXUINT_LEAST64_MAX	maximum value of an object of type uint_least8_t, uint_least16_t, uint_least32_t, uint_least64_t (macro constant)
UINTPTR_MAX	maximum value of an object of type uintptr_t (macro constant)
UINTMAX_MAX	maximum value of an object of type uintmax_t (macro constant)
Limits of other integer types
PTRDIFF_MIN (C++11)	minimum value of object of std::ptrdiff_t type (macro constant)
PTRDIFF_MAX (C++11)	maximum value of object of std::ptrdiff_t type (macro constant)
SIZE_MAX (C++11)	maximum value of object of std::size_t type (macro constant)
SIG_ATOMIC_MIN (C++11)	minimum value of object of std::sig_atomic_t type (macro constant)
SIG_ATOMIC_MAX (C++11)	maximum value of object of std::sig_atomic_t type (macro constant)
WCHAR_MIN (C++11)	minimum value of object of wchar_t type (macro constant)
WCHAR_MAX (C++11)	maximum value of object of wchar_t type (macro constant)
WINT_MIN (C++11)	minimum value of object of std::wint_t type (macro constant)
WINT_MAX (C++11)	maximum value of object of std::wint_t type (macro constant)
Function macros for integer constants
INT8_CINT16_CINT32_CINT64_C	expands to an integer constant expression having the value specified by its argument and the type int_least8_t, int_least16_t, int_least32_t, int_least64_t respectively (function macro)
INTMAX_C	expands to an integer constant expression having the value specified by its argument and the type intmax_t (function macro)
UINT8_CUINT16_CUINT32_CUINT64_C	expands to an integer constant expression having the value specified by its argument and the type uint_least8_t, uint_least16_t, uint_least32_t, uint_least64_t respectively (function macro)
UINTMAX_C	expands to an integer constant expression having the value specified by its argument and the type uintmax_t (function macro)

Synopsis

namespace std {
  using int8_t = /*signed integer type*/ ; // optional
  using int16_t = /*signed integer type*/ ; // optional
  using int32_t = /*signed integer type*/ ; // optional
  using int64_t = /*signed integer type*/ ; // optional
  using int_fast8_t = /*signed integer type*/ ;
  using int_fast16_t = /*signed integer type*/ ;
  using int_fast32_t = /*signed integer type*/ ;
  using int_fast64_t = /*signed integer type*/ ;
  using int_least8_t = /*signed integer type*/ ;
  using int_least16_t = /*signed integer type*/ ;
  using int_least32_t = /*signed integer type*/ ;
  using int_least64_t = /*signed integer type*/ ;
  using intmax_t = /*signed integer type*/ ;
  using intptr_t = /*signed integer type*/ ; // optional
  using uint8_t = /*unsigned integer type*/ ; // optional
  using uint16_t = /*unsigned integer type*/ ; // optional
  using uint32_t = /*unsigned integer type*/ ; // optional
  using uint64_t = /*unsigned integer type*/ ; // optional
  using uint_fast8_t = /*unsigned integer type*/ ;
  using uint_fast16_t = /*unsigned integer type*/ ;
  using uint_fast32_t = /*unsigned integer type*/ ;
  using uint_fast64_t = /*unsigned integer type*/ ;
  using uint_least8_t = /*unsigned integer type*/ ;
  using uint_least16_t = /*unsigned integer type*/ ;
  using uint_least32_t = /*unsigned integer type*/ ;
  using uint_least64_t = /*unsigned integer type*/ ;
  using uintmax_t = /*unsigned integer type*/ ;
  using uintptr_t = /*unsigned integer type*/ ; // optional
}
/* also defines macros of the form:
INT_[FAST LEAST]{8 16 32 64}_MIN
[U]INT_[FAST LEAST]{8 16 32 64}_MAX
INT{MAX PTR}_MIN
[U]INT{MAX PTR}_MAX
{PTRDIFF SIG_ATOMIC WCHAR WINT}{_MAX _MIN}
SIZE_MAX
*/
/* also defines function-like macros of the form:
[U]INT{8 16 32 64 MAX}_C
*/