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Standard library header <stdatomic.h>

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This header was originally in the C standard library.

This header is part of the concurrency support library.

It is unspecified whether <stdatomic.h> provides any declarations in namespace std.

Contents

Macros

(C++23)
compatibility macro such that _Atomic(T) is identical to std::atomic<T>
(function macro) [edit]
initializes an std::atomic_flag to false
(macro constant) [edit]

Types

the lock-free boolean atomic type
(class) [edit]
defines memory ordering constraints for the given atomic operation
(enum) [edit]
std::atomic<bool>
(typedef) [edit]
std::atomic<char>
(typedef) [edit]
std::atomic<signed char>
(typedef) [edit]
std::atomic<unsigned char>
(typedef) [edit]
std::atomic<short>
(typedef) [edit]
std::atomic<unsigned short>
(typedef) [edit]
std::atomic<int>
(typedef) [edit]
std::atomic<unsigned int>
(typedef) [edit]
std::atomic<long>
(typedef) [edit]
std::atomic<unsigned long>
(typedef) [edit]
std::atomic<long long>
(typedef) [edit]
std::atomic<unsigned long long>
(typedef) [edit]
std::atomic<char8_t>
(typedef) [edit]
std::atomic<char16_t>
(typedef) [edit]
std::atomic<char32_t>
(typedef) [edit]
std::atomic<wchar_t>
(typedef) [edit]
(C++11)(optional)
std::atomic<std::int8_t>
(typedef) [edit]
(C++11)(optional)
std::atomic<std::uint8_t>
(typedef) [edit]
(C++11)(optional)
std::atomic<std::int16_t>
(typedef) [edit]
(C++11)(optional)
std::atomic<std::uint16_t>
(typedef) [edit]
(C++11)(optional)
std::atomic<std::int32_t>
(typedef) [edit]
(C++11)(optional)
std::atomic<std::uint32_t>
(typedef) [edit]
(C++11)(optional)
std::atomic<std::int64_t>
(typedef) [edit]
(C++11)(optional)
std::atomic<std::uint64_t>
(typedef) [edit]
std::atomic<std::int_least8_t>
(typedef) [edit]
std::atomic<std::uint_least8_t>
(typedef) [edit]
std::atomic<std::int_least16_t>
(typedef) [edit]
std::atomic<std::uint_least16_t>
(typedef) [edit]
std::atomic<std::int_least32_t>
(typedef) [edit]
std::atomic<std::uint_least32_t>
(typedef) [edit]
std::atomic<std::int_least64_t>
(typedef) [edit]
std::atomic<std::uint_least64_t>
(typedef) [edit]
std::atomic<std::int_fast8_t>
(typedef) [edit]
std::atomic<std::uint_fast8_t>
(typedef) [edit]
std::atomic<std::int_fast16_t>
(typedef) [edit]
std::atomic<std::uint_fast16_t>
(typedef) [edit]
std::atomic<std::int_fast32_t>
(typedef) [edit]
std::atomic<std::uint_fast32_t>
(typedef) [edit]
std::atomic<std::int_fast64_t>
(typedef) [edit]
std::atomic<std::uint_fast64_t>
(typedef) [edit]
(C++11)(optional)
std::atomic<std::intptr_t>
(typedef) [edit]
(C++11)(optional)
std::atomic<std::uintptr_t>
(typedef) [edit]
std::atomic<std::size_t>
(typedef) [edit]
std::atomic<std::ptrdiff_t>
(typedef) [edit]
std::atomic<std::intmax_t>
(typedef) [edit]
std::atomic<std::uintmax_t>
(typedef) [edit]

Functions

checks if the atomic type's operations are lock-free
(function template) [edit]
atomically replaces the value of the atomic object with a non-atomic argument
(function template) [edit]
atomically obtains the value stored in an atomic object
(function template) [edit]
atomically replaces the value of the atomic object with non-atomic argument and returns the old value of the atomic
(function template) [edit]
atomically compares the value of the atomic object with non-atomic argument and performs atomic exchange if equal or atomic load if not
(function template) [edit]
adds a non-atomic value to an atomic object and obtains the previous value of the atomic
(function template) [edit]
subtracts a non-atomic value from an atomic object and obtains the previous value of the atomic
(function template) [edit]
replaces the atomic object with the result of bitwise AND with a non-atomic argument and obtains the previous value of the atomic
(function template) [edit]
replaces the atomic object with the result of bitwise OR with a non-atomic argument and obtains the previous value of the atomic
(function template) [edit]
replaces the atomic object with the result of bitwise XOR with a non-atomic argument and obtains the previous value of the atomic
(function template) [edit]
atomically sets the flag to true and returns its previous value
(function) [edit]
atomically sets the value of the flag to false
(function) [edit]
generic memory order-dependent fence synchronization primitive
(function) [edit]
fence between a thread and a signal handler executed in the same thread
(function) [edit]

[edit] Synopsis

template<class T>
  using __std_atomic = std::atomic<T>;        // exposition only
 
#define _Atomic(T) __std_atomic<T>
 
#define ATOMIC_BOOL_LOCK_FREE /* see description */
#define ATOMIC_CHAR_LOCK_FREE /* see description */
#define ATOMIC_CHAR16_T_LOCK_FREE /* see description */
#define ATOMIC_CHAR32_T_LOCK_FREE /* see description */
#define ATOMIC_WCHAR_T_LOCK_FREE /* see description */
#define ATOMIC_SHORT_LOCK_FREE /* see description */
#define ATOMIC_INT_LOCK_FREE /* see description */
#define ATOMIC_LONG_LOCK_FREE /* see description */
#define ATOMIC_LLONG_LOCK_FREE /* see description */
#define ATOMIC_POINTER_LOCK_FREE /* see description */
 
using std::memory_order;                // see description
using std::memory_order_relaxed;        // see description
using std::memory_order_consume;        // see description
using std::memory_order_acquire;        // see description
using std::memory_order_release;        // see description
using std::memory_order_acq_rel;        // see description
using std::memory_order_seq_cst;        // see description
 
using std::atomic_flag;                 // see description
 
using std::atomic_bool;                 // see description
using std::atomic_char;                 // see description
using std::atomic_schar;                // see description
using std::atomic_uchar;                // see description
using std::atomic_short;                // see description
using std::atomic_ushort;               // see description
using std::atomic_int;                  // see description
using std::atomic_uint;                 // see description
using std::atomic_long;                 // see description
using std::atomic_ulong;                // see description
using std::atomic_llong;                // see description
using std::atomic_ullong;               // see description
using std::atomic_char8_t;              // see description
using std::atomic_char16_t;             // see description
using std::atomic_char32_t;             // see description
using std::atomic_wchar_t;              // see description
using std::atomic_int8_t;               // see description
using std::atomic_uint8_t;              // see description
using std::atomic_int16_t;              // see description
using std::atomic_uint16_t;             // see description
using std::atomic_int32_t;              // see description
using std::atomic_uint32_t;             // see description
using std::atomic_int64_t;              // see description
using std::atomic_uint64_t;             // see description
using std::atomic_int_least8_t;         // see description
using std::atomic_uint_least8_t;        // see description
using std::atomic_int_least16_t;        // see description
using std::atomic_uint_least16_t;       // see description
using std::atomic_int_least32_t;        // see description
using std::atomic_uint_least32_t;       // see description
using std::atomic_int_least64_t;        // see description
using std::atomic_uint_least64_t;       // see description
using std::atomic_int_fast8_t;          // see description
using std::atomic_uint_fast8_t;         // see description
using std::atomic_int_fast16_t;         // see description
using std::atomic_uint_fast16_t;        // see description
using std::atomic_int_fast32_t;         // see description
using std::atomic_uint_fast32_t;        // see description
using std::atomic_int_fast64_t;         // see description
using std::atomic_uint_fast64_t;        // see description
using std::atomic_intptr_t;             // see description
using std::atomic_uintptr_t;            // see description
using std::atomic_size_t;               // see description
using std::atomic_ptrdiff_t;            // see description
using std::atomic_intmax_t;             // see description
using std::atomic_uintmax_t;            // see description
 
using std::atomic_is_lock_free;                         // see description
using std::atomic_load;                                 // see description
using std::atomic_load_explicit;                        // see description
using std::atomic_store;                                // see description
using std::atomic_store_explicit;                       // see description
using std::atomic_exchange;                             // see description
using std::atomic_exchange_explicit;                    // see description
using std::atomic_compare_exchange_strong;              // see description
using std::atomic_compare_exchange_strong_explicit;     // see description
using std::atomic_compare_exchange_weak;                // see description
using std::atomic_compare_exchange_weak_explicit;       // see description
using std::atomic_fetch_add;                            // see description
using std::atomic_fetch_add_explicit;                   // see description
using std::atomic_fetch_sub;                            // see description
using std::atomic_fetch_sub_explicit;                   // see description
using std::atomic_fetch_or;                             // see description
using std::atomic_fetch_or_explicit;                    // see description
using std::atomic_fetch_xor;                            // see description
using std::atomic_fetch_xor_explicit;                   // see description
using std::atomic_fetch_and;                            // see description
using std::atomic_fetch_and_explicit;                   // see description
using std::atomic_flag_test_and_set;                    // see description
using std::atomic_flag_test_and_set_explicit;           // see description
using std::atomic_flag_clear;                           // see description
using std::atomic_flag_clear_explicit;                  // see description
 
#define ATOMIC_FLAG_INIT /* see description */
 
using std::atomic_thread_fence;                         // see description
using std::atomic_signal_fence;                         // see description