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    Standard library header <stdatomic.h> (C11)

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    This header provides atomic operations, in particular, it's a part of the concurrency support library.

    Atomic operations

    Operations on atomic types
    (C11)
    		 indicates that the given atomic type is lock-free
    (macro constant) [edit]
    (C11)
    		 indicates whether the atomic object is lock-free
    (function) [edit]
    (C11)
    		 stores a value in an atomic object
    (function) [edit]
    (C11)
    		 reads a value from an atomic object
    (function) [edit]
    (C11)
    		 swaps a value with the value of an atomic object
    (function) [edit]
    (C11)
    		 swaps a value with an atomic object if the old value is what is expected, otherwise reads the old value
    (function) [edit]
    (C11)
    		 atomic addition
    (function) [edit]
    (C11)
    		 atomic subtraction
    (function) [edit]
    (C11)
    		 atomic bitwise OR
    (function) [edit]
    (C11)
    		 atomic bitwise exclusive OR
    (function) [edit]
    (C11)
    		 atomic bitwise AND
    (function) [edit]
    Flag type and operations
    (C11)
    		 lock-free atomic boolean flag
    (struct)[edit]
    (C11)
    		 sets an atomic_flag to true and returns the old value
    (function) [edit]
    (C11)
    		 sets an atomic_flag to false
    (function) [edit]
    Initialization
    (C11)
    		 initializes an existing atomic object
    (function) [edit]
    (C11)(deprecated in C17)(removed in C23)
    		 initializes a new atomic object
    (function macro) [edit]
    (C11)
    		 initializes a new atomic_flag
    (macro constant) [edit]
    Memory synchronization ordering
    (C11)
    		 defines memory ordering constraints
    (enum) [edit]
    (C11)
    		 breaks a dependency chain for memory_order_consume
    (function macro) [edit]
    (C11)
    		 generic memory order-dependent fence synchronization primitive
    (function) [edit]
    (C11)
    		 fence between a thread and a signal handler executed in the same thread
    (function) [edit]
    Convenience type aliases
    Typedef name Full type name
    atomic_bool (C11) _Atomic _Bool
    atomic_char (C11) _Atomic char
    atomic_schar (C11) _Atomic signed char
    atomic_uchar (C11) _Atomic unsigned char
    atomic_short (C11) _Atomic short
    atomic_ushort (C11) _Atomic unsigned short
    atomic_int (C11) _Atomic int
    atomic_uint (C11) _Atomic unsigned int
    atomic_long (C11) _Atomic long
    atomic_ulong (C11) _Atomic unsigned long
    atomic_llong (C11) _Atomic long long
    atomic_ullong (C11) _Atomic unsigned long long
    atomic_char8_t (C23) _Atomic char8_t
    atomic_char16_t (C11) _Atomic char16_t
    atomic_char32_t (C11) _Atomic char32_t
    atomic_wchar_t (C11) _Atomic wchar_t
    atomic_int_least8_t (C11) _Atomic int_least8_t
    atomic_uint_least8_t (C11) _Atomic uint_least8_t
    atomic_int_least16_t (C11) _Atomic int_least16_t
    atomic_uint_least16_t (C11) _Atomic uint_least16_t
    atomic_int_least32_t (C11) _Atomic int_least32_t
    atomic_uint_least32_t (C11) _Atomic uint_least32_t
    atomic_int_least64_t (C11) _Atomic int_least64_t
    atomic_uint_least64_t (C11) _Atomic uint_least64_t
    atomic_int_fast8_t (C11) _Atomic int_fast8_t
    atomic_uint_fast8_t (C11) _Atomic uint_fast8_t
    atomic_int_fast16_t (C11) _Atomic int_fast16_t
    atomic_uint_fast16_t (C11) _Atomic uint_fast16_t
    atomic_int_fast32_t (C11) _Atomic int_fast32_t
    atomic_uint_fast32_t (C11) _Atomic uint_fast32_t
    atomic_int_fast64_t (C11) _Atomic int_fast64_t
    atomic_uint_fast64_t (C11) _Atomic uint_fast64_t
    atomic_intptr_t (C11) _Atomic intptr_t
    atomic_uintptr_t (C11) _Atomic uintptr_t
    atomic_size_t (C11) _Atomic size_t
    atomic_ptrdiff_t (C11) _Atomic ptrdiff_t
    atomic_intmax_t (C11) _Atomic intmax_t
    atomic_uintmax_t (C11) _Atomic uintmax_t

    Synopsis

    This section is incomplete
    Reason: add more from 7.17 Atomics <stdatomic.h> and B.16 Atomics <stdatomic.h> 
    #define __STDC_VERSION_STDATOMIC_H__ 202311L

void atomic_init(volatile A* obj, /*C*/ value);
/*type*/ kill_dependency(/*type*/ y);
void atomic_thread_fence(memory_order order);
void atomic_signal_fence(memory_order order);
bool atomic_is_lock_free(const volatile A* obj);
void atomic_store(volatile A* object, /*C*/ desired);
void atomic_store_explicit(volatile A* object, /*C*/ desired, memory_order order);
/*C*/ atomic_load(const volatile A* object);
/*C*/ atomic_load_explicit(const volatile A* object, memory_order order);
/*C*/ atomic_exchange(volatile A* object, /*C*/ desired);
/*C*/ atomic_exchange_explicit(volatile A* object, /*C*/ desired, memory_order order);
bool atomic_compare_exchange_strong(volatile A* object, /*C*/* expected, /*C*/ desired);
bool atomic_compare_exchange_strong_explicit(volatile A* object, /*C*/* expected,
/*C*/ desired, memory_order success, memory_order failure);
bool atomic_compare_exchange_weak(volatile A* object, /*C*/* expected, /*C*/ desired);
bool atomic_compare_exchange_weak_explicit(volatile A* object, /*C*/* expected,
/*C*/ desired, memory_order success, memory_order failure);
/*C*/ /*atomic_fetch_key*/(volatile A* object, M operand);
/*C*/ /*atomic_fetch_key_explicit*/(volatile A* object, M operand, memory_order order);
bool atomic_flag_test_and_set(volatile atomic_flag* object);
bool atomic_flag_test_and_set_explicit(volatile atomic_flag* object,
memory_order order);
void atomic_flag_clear(volatile atomic_flag* object);
void atomic_flag_clear_explicit(volatile atomic_flag* object,
                                memory_order order);