std::atomic_flag_test, std::atomic_flag_test_explicit
From cppreference.com
| Defined in header <atomic>
|
||
| bool atomic_flag_test( const volatile std::atomic_flag* object ) noexcept; |
(1) | (since C++20) |
| bool atomic_flag_test( const std::atomic_flag* object ) noexcept; |
(2) | (since C++20) |
| bool atomic_flag_test_explicit( const volatile std::atomic_flag* object, std::memory_order order ) noexcept; |
(3) | (since C++20) |
| bool atomic_flag_test_explicit( const std::atomic_flag* object, std::memory_order order ) noexcept; |
(4) | (since C++20) |
Atomically reads the value of the *object and returns the value.
1,2) The memory synchronization order is std::memory_order_seq_cst.
3,4) The memory synchronization order is order.
If order is one of std::memory_order::release and std::memory_order::acq_rel, the behavior is undefined.
Parameters
| object | - | pointer to the atomic_flag object to read
|
| order | - | the memory synchronization ordering |
Return value
The value atomically read.
Notes
| Feature-test macro | Value | Std | Feature |
|---|---|---|---|
__cpp_lib_atomic_flag_test |
201907L | (C++20) | std::atomic_flag::test
|
Example
| This section is incomplete Reason: no example |
See also
| (C++20) |
atomically returns the value of the flag (public member function of std::atomic_flag) |