Linux Manuals

std::atomic<T>::is_lock_free – std::atomic<T>::is_lock_free Synopsis bool is_lock_free() const noexcept; (since C++ 11) bool is_lock_free() const volatile noexcept; Checks whether the atomic operations on all objects of this type are lock-free. Parameters (none) Return value true if the atomic operations on the objects of this type are lock-free, false otherwise. Notes All atomic types except for std::atomic_flag…

std::atomic<T>::is_always_lock_free – std::atomic<T>::is_always_lock_free Synopsis static constexpr bool is_always_lock_free = /*implementation-defined*/; (since C++17) Equals true if this atomic type is always lock-free and false if it is never or sometimes lock-free. The value of this constant is consistent with both the macro ATOMIC_xxx_LOCK_FREE, where defined, with the member function is_lock_free and non-member function std::atomic_is_lock_free. Notes There…

std::atomic<T>::fetch_xor – std::atomic<T>::fetch_xor Synopsis T fetch_xor( T arg, std::memory_order order = std::memory_order_seq_cst ) noexcept; (since C++11) T fetch_xor( T arg, (member only of atomic<Integral> template specialization) std::memory_order order = std::memory_order_seq_cst ) volatile noexcept; Atomically replaces the current value with the result of bitwise XOR of the value and arg. The operation is read-modify-write operation. Memory…

std::atomic<T>::fetch_sub – std::atomic<T>::fetch_sub Synopsis member only of atomic<Integral>(C++11) and atomic<Floating>(C++20) template specializations T fetch_sub( T arg, std::memory_order order = std::memory_order_seq_cst ) noexcept; T fetch_sub( T arg, std::memory_order order = std::memory_order_seq_cst ) volatile noexcept; member only of atomic<T*> template specialization (1) T* fetch_sub( std::ptrdiff_t arg, std::memory_order order = std::memory_order_seq_cst ) noexcept; (2) T* fetch_sub( std::ptrdiff_t arg,…

std::atomic<T>::fetch_or – std::atomic<T>::fetch_or Synopsis T fetch_or( T arg, std::memory_order order = std::memory_order_seq_cst ) noexcept; (since C++11) T fetch_or( T arg, (member only of atomic<Integral> template specialization) std::memory_order order = std::memory_order_seq_cst ) volatile noexcept; Atomically replaces the current value with the result of bitwise OR of the value and arg. The operation is read-modify-write operation. Memory…

std::atomic<T>::fetch_and – std::atomic<T>::fetch_and Synopsis T fetch_and( T arg, std::memory_order order = std::memory_order_seq_cst ) noexcept; (since C++11) T fetch_and( T arg, (member only of atomic<Integral> template specialization) std::memory_order order = std::memory_order_seq_cst ) volatile noexcept; Atomically replaces the current value with the result of bitwise AND of the value and arg. The operation is read-modify-write operation. Memory…

std::atomic<T>::fetch_add – std::atomic<T>::fetch_add Synopsis member only of atomic<Integral>(C++11) and atomic<Floating>(C++20) template specializations T fetch_add( T arg, std::memory_order order = std::memory_order_seq_cst ) noexcept; T fetch_add( T arg, std::memory_order order = std::memory_order_seq_cst ) volatile noexcept; member only of atomic<T*> template specialization (1) T* fetch_add( std::ptrdiff_t arg, std::memory_order order = std::memory_order_seq_cst ) noexcept; (2) T* fetch_add( std::ptrdiff_t arg,…

std::atomic<T>::exchange – std::atomic<T>::exchange Synopsis T exchange( T desired, std::memory_order order = std::memory_order_seq_cst ) noexcept; (since C++11) T exchange( T desired, std::memory_order order = std::memory_order_seq_cst ) volatile noexcept; Atomically replaces the underlying value with desired. The operation is read-modify-write operation. Memory is affected according to the value of order. Parameters desired – value to assign order…

std::atomic<T>::compare_exchange_weak,std::atomic<T>::compare_exchange_strong – std::atomic<T>::compare_exchange_weak,std::atomic<T>::compare_exchange_strong Synopsis bool compare_exchange_weak( T& expected, T desired, std::memory_order success, std::memory_order failure ) noexcept; bool compare_exchange_weak( T& expected, T desired, std::memory_order success, std::memory_order failure ) volatile noexcept; bool compare_exchange_weak( T& expected, T desired, std::memory_order order = std::memory_order_seq_cst ) noexcept; bool compare_exchange_weak( T& expected, T desired, std::memory_order order = std::memory_order_seq_cst ) volatile noexcept; (1)…

std::atomic<T>::atomic – std::atomic<T>::atomic Synopsis atomic() noexcept = default; (1)(since C++ 11) constexpr atomic(T desired) noexcept; (2)(since C++ 11) atomic(const atomic &) = delete; (3)(since C++ 11) Constructs new atomic variable. 1) The default constructor is trivial: no initialization takes place other than zero_initialization of static and thread-local objects. std::atomic_init may be used to complete initialization….

std::atomic – std::atomic Synopsis Defined in header<atomic> template <class T> (1)(since C++ 11) struct atomic; template <class T> (2)(since C++ 11) struct atomic<T *>; Defined in header<memory> template <class T> (3)(since C++ 20) struct atomic<std::shared_ptr<T>>; template <class T> (4)(since C++ 20) struct atomic<std::weak_ptr<T>>; Each instantiation and full specialization of the std::atomic template defines an atomic…

std::atomic(std::weak_ptr) – std::atomic(std::weak_ptr) Synopsis template <class T> struct std::atomic<std::weak_ptr<T>>; (since C++20) The partial template specialization of std::atomic for std::weak_ptr<T> allows users to manipulate weak_ptr objects atomically. If multiple threads of execution access the same std::weak_ptr object without synchronization and any of those accesses uses a non-const member function of weak_ptr then a data race will…

std::atomic(std::shared_ptr) – std::atomic(std::shared_ptr) Synopsis template <class T> struct std::atomic<std::shared_ptr<T>>; (since C++20) The partial template specialization of std::atomic for std::shared_ptr<T> allows users to manipulate shared_ptr objects atomically. If multiple threads of execution access the same std::shared_ptr object without synchronization and any of those accesses uses a non-const member function of shared_ptr then a data race will…

std::atoi,std::atol,std::atoll – std::atoi,std::atol,std::atoll Synopsis Defined in header <cstdlib> int atoi( const char *str ); long atol( const char *str ); long long atoll( const char *str ); (since C++11) Interprets an integer value in a byte string pointed to by str. Discards any whitespace characters until the first non-whitespace character is found, then takes as…

std::atof – std::atof Synopsis Defined in header<cstdlib> double atof(const char *str); Interprets a floating point value in a byte string pointed to by str. Function discards any whitespace characters (as determined by std::isspace()) until first non-whitespace character is found. Then it takes as many characters as possible to form a valid floating-point representation and converts…

std::atexit – std::atexit Synopsis Defined in header<cstdlib> int atexit(/*c-atexit-handler*/ *func); (until C++ 11) int atexit(/*atexit-handler*/ *func); int atexit(/*c-atexit-handler*/ *func) noexcept; (1)(since C++ 11) int atexit(/*atexit-handler*/ *func) noexcept; extern "C++" using /*atexit-handler*/ = void(); // exposition-only (2) extern "C" using /*c-atexit-handler*/ = void(); // exposition-only Registers the function pointed to by func to be called on…

std::atanh,std::atanh,std::atanhl – std::atanh,std::atanh,std::atanhl Synopsis Defined in header <cmath> float atanh ( float arg ); (1) (since C++11) float atanhf( float arg ); double atanh ( double arg ); (2) (since C++11) long double atanh ( long double arg ); (3) (since C++11) long double atanhl( long double arg ); double atanh ( IntegralType arg );…

std::atanh(std::complex) – std::atanh(std::complex) Synopsis Defined in header<complex> template <class T> (since C++ 11) complex<T> atanh(const complex<T> &z); Computes the complex arc hyperbolic tangent of z with branch cuts outside the interval [−1; +1] along the real axis. Parameters z – complex value Return value If no errors occur, the complex arc hyperbolic tangent of z…

std::atan2,std::atan2f,std::atan2l – std::atan2,std::atan2f,std::atan2l Synopsis Defined in header <cmath> float atan2 ( float y, float x ); float atan2f( float y, float x ); (since C++11) double atan2 ( double y, double x ); (1) (2) long double atan2 ( long double y, long double x ); long double atan2l( long double y, long double x…

std::atan2(std::valarray) – std::atan2(std::valarray) Synopsis Defined in header<valarray> template <class T> (1) std::valarray<T> atan2(const std::valarray<T> &y, const std::valarray<T> &x); template <class T> std::valarray<T> atan2(const std::valarray<T> &y, (2) const typename std::valarray<T>::value_type &vx); template <class T> std::valarray<T> atan2(const typename std::valarray<T>::value_type &vy, (3) const std::valarray<T> &x); Computes the inverse tangent of y/x using the signs of arguments to correctly…