Standard library header <stdatomic.h>

From cppreference.com
< cpp‎ | header
 
 
Standard Library headers
Note: a slash '/' in a revision mark means that the header was deprecated and/or removed.
Language Support
Concepts
<concepts> (C++20)
Diagnostics
<system_error> (C++11)
General utilities
<bitset>
<tuple> (C++11)
<optional> (C++17)
<any> (C++17)
<variant> (C++17)
<type_traits> (C++11)
<ratio> (C++11)
<chrono> (C++11)
Strings
<charconv> (C++17)
<format> (C++20)

<cwchar>
<cuchar> (C++11)

Localization
<codecvt> (C++11/17)

Containers
<span> (C++20)
<array> (C++11)
<vector>
Iterators
<iterator>
Ranges
<ranges> (C++20)
Algorithms
<execution> (C++17)
Numerics
<bit> (C++20)
<numbers> (C++20)
<cfenv> (C++11)
<cmath>
Input/Output
<cstdio>
<cinttypes> (C++11)
<strstream> (C++98/)

Regular expressions
<regex> (C++11)
Filesystem support
<filesystem> (C++17)
Thread support
<thread> (C++11)
<atomic> (C++11)
<mutex> (C++11)
<shared_mutex> (C++14)
<condition_variable> (C++11)  
<future> (C++11)
<stop_token> (C++20)
<semaphore> (C++20)

<latch> (C++20)
<barrier> (C++20)

C compatibility
<cstdbool> (C++11/17/20)
<ccomplex> (C++11/17/20)
<ctgmath> (C++11/17/20)
<cstdalign> (C++11/17/20)
<ciso646> (until C++20)
<stdatomic.h>
 

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.

Macros

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

Types

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

Functions

checks if the atomic type's operations are lock-free
(function template)
atomically replaces the value of the atomic object with a non-atomic argument
(function template)
atomically obtains the value stored in an atomic object
(function template)
atomically replaces the value of the atomic object with non-atomic argument and returns the old value of the atomic
(function template)
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)
adds a non-atomic value to an atomic object and obtains the previous value of the atomic
(function template)
subtracts a non-atomic value from an atomic object and obtains the previous value of the atomic
(function template)
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)
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)
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)
atomically sets the flag to true and returns its previous value
(function)
atomically sets the value of the flag to false
(function)
generic memory order-dependent fence synchronization primitive
(function)
fence between a thread and a signal handler executed in the same thread
(function)

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