Atomic operations library

 

C++

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)

 

Atomic operations library

Types

atomic (C++11)

atomic_is_lock_free (C++11)

Functions

atomic_store atomic_store_explicit (C++11) (C++11)

atomic_load atomic_load_explicit (C++11) (C++11)

atomic_exchange atomic_exchange_explicit (C++11) (C++11)

atomic_compare_exchange_weak atomic_compare_exchange_weak_explicit atomic_compare_exchange_strong atomic_compare_exchange_strong_explicit (C++11) (C++11) (C++11) (C++11)

atomic_fetch_add atomic_fetch_add_explicit (C++11) (C++11)

atomic_fetch_sub atomic_fetch_sub_explicit (C++11) (C++11)

atomic_fetch_and atomic_fetch_and_explicit (C++11) (C++11)

atomic_fetch_or atomic_fetch_or_explicit (C++11) (C++11)

atomic_fetch_xor atomic_fetch_xor_explicit (C++11) (C++11)

Atomic flags

atomic_flag (C++11)

atomic_flag_test_and_set atomic_flag_test_and_set_explicit (C++11) (C++11)

atomic_flag_clear atomic_flag_clear_explicit (C++11) (C++11)

Initialization

atomic_init (C++11)

ATOMIC_VAR_INIT (C++11)

ATOMIC_FLAG_INIT (C++11)

Memory ordering

memory_order (C++11)

kill_dependency (C++11)

atomic_thread_fence (C++11)

atomic_signal_fence (C++11)

 

The atomic library provides components for fine-grained atomic operations allowing for lockless concurrent programming. Each atomic operation is indivisible with regards to any other atomic operation that involves the same object. Atomic objects are the only C++ objects free of data races; that is, if one thread writes to an atomic while another thread reads from it, the behavior is well-defined.

Defined in header <atomic>
Atomic types
atomic (C++11)	atomic class template and specializations for bool, integral, and pointer types (class template)
atomic_is_lock_free (C++11)	checks if the atomic type's operations are lock-free (function template)
Operations on atomic types
atomic_store atomic_store_explicit (C++11) (C++11)	atomically replaces the value of the atomic object with a non-atomic argument (function template)
atomic_load atomic_load_explicit (C++11) (C++11)	atomically obtains the value stored in an atomic object (function template)
atomic_exchange atomic_exchange_explicit (C++11) (C++11)	atomically replaces the value of the atomic object with non-atomic argument and returns the old value of the atomic (function template)
atomic_compare_exchange_weak atomic_compare_exchange_weak_explicit atomic_compare_exchange_strong atomic_compare_exchange_strong_explicit (C++11) (C++11) (C++11) (C++11)	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)
atomic_fetch_add atomic_fetch_add_explicit (C++11) (C++11)	adds a non-atomic value to an atomic object and obtains the previous value of the atomic (function template)
atomic_fetch_sub atomic_fetch_sub_explicit (C++11) (C++11)	subtracts a non-atomic value from an atomic object and obtains the previous value of the atomic (function template)
atomic_fetch_and atomic_fetch_and_explicit (C++11) (C++11)	replaces the atomic object with the result of logical AND with a non-atomic argument and obtains the previous value of the atomic (function template)
atomic_fetch_or atomic_fetch_or_explicit (C++11) (C++11)	replaces the atomic object with the result of logical OR with a non-atomic argument and obtains the previous value of the atomic (function template)
atomic_fetch_xor atomic_fetch_xor_explicit (C++11) (C++11)	replaces the atomic object with the result of logical XOR with a non-atomic argument and obtains the previous value of the atomic (function template)
Flag type and operations
atomic_flag (C++11)	the lock-free boolean atomic type (class)
atomic_flag_test_and_set atomic_flag_test_and_set_explicit (C++11) (C++11)	atomically sets the flag to true and returns its previous value (function)
atomic_flag_clear atomic_flag_clear_explicit (C++11) (C++11)	atomically sets the value of the flag to false (function)
Initialization
atomic_init (C++11)	non-atomic initialization of a default-constructed atomic object (function template)
ATOMIC_VAR_INIT (C++11)	constant initialization of an atomic variable of static storage duration (function macro)
ATOMIC_FLAG_INIT (C++11)	initializes an std::atomic_flag to false (macro constant)
Memory synchronization ordering
memory_order (C++11)	defines memory ordering constraints for the given atomic operation (typedef)
kill_dependency (C++11)	removes the specified object from the std::memory_order_consume dependency tree (function template)
atomic_thread_fence (C++11)	generic memory order-dependent fence synchronization primitive (function)
atomic_signal_fence (C++11)	fence between a thread and a signal handler executed in the same thread (function)