std::atomic_flag::test_and_set

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C++ Standard Library
Language 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)
std::atomic_flag
Member functions atomic_flag::atomic_flag atomic_flag::operator= atomic_flag::clear atomic_flag::test_and_set

Defined in header <atomic>
bool test_and_set(std::memory_order order = std::memory_order_seq_cst) volatile;	(1)	(since C++11)
bool test_and_set(std::memory_order order = std::memory_order_seq_cst);	(2)	(since C++11)

Atomically changes the state of a std::atomic_flag to set (true) and returns the value it held before.

[edit] Parameters

order

-

the memory sycnhronization ordering for this operation

[edit] Exceptions

[edit] See also

clear	atomically sets flag to false (public member function)
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)
memory_order (C++11)	defines memory ordering constraints for the given atomic operation (typedef)