Standard library header <cstddef>

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

This header is part of the utility library.

Macros

NULL	implementation-defined null pointer constant (macro constant)
offsetof	byte offset from the beginning of a standard-layout type to specified member (function macro)

Types

size_t	unsigned integer type returned by the `sizeof` operator (typedef)
ptrdiff_t	signed integer type returned when subtracting two pointers (typedef)
nullptr_t (C++11)	the type of the null pointer literal `nullptr` (typedef)
max_align_t (C++11)	POD type with alignment requirement as great as any other scalar type (typedef)
byte (C++17)	the byte type (enum)

Synopsis

namespace std {
    using ptrdiff_t = /*see definition*/ ;
    using size_t = /*see definition*/ ;
    using max_align_t = /*see definition*/ ;
    using nullptr_t = decltype(nullptr);
 
    enum class byte : unsigned char {} ;
    template <class IntegerType>
    constexpr byte& operator<<=(byte& b, IntegerType shift) noexcept;
    template <class IntegerType>
    constexpr byte operator<<(byte b, IntegerType shift) noexcept;
    template <class IntegerType>
    constexpr byte& operator>>=(byte& b, IntegerType shift) noexcept;
    template <class IntegerType>
    constexpr byte operator>>(byte b, IntegerType shift) noexcept;
 
    constexpr byte& operator|=(byte& l, byte r) noexcept;
    constexpr byte operator|(byte l, byte r) noexcept;
    constexpr byte& operator&=(byte& l, byte r) noexcept;
    constexpr byte operator&(byte l, byte r) noexcept;
    constexpr byte& operator^=(byte& l, byte r) noexcept;
    constexpr byte operator^(byte l, byte r) noexcept;
    constexpr byte operator~(byte b) noexcept;
    template <class IntegerType>
    constexpr IntegerType to_integer(byte b) noexcept; 
}
#define NULL /*see definition*/
#define offsetof(P, D) /*see definition*/

Notes

NULL is also defined in the following headers:
std::size_t is also defined in the following headers:

Language
Standard library headers
Concepts
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