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Defined in header <stdatomic.h> | ||
C atomic_load(constvolatile A* obj); | (1) | (since C11) |
C atomic_load_explicit(constvolatile A* obj,memory_order order); | (2) | (since C11) |
Atomically loads and returns the current value of the atomic variable pointed to byobj. The operation is atomic read operation.
The first version orders memory accesses according tomemory_order_seq_cst, the second version orders memory accesses according toorder.order must be one ofmemory_order_relaxed,memory_order_consume,memory_order_acquire ormemory_order_seq_cst. Otherwise the behavior is undefined.
This is ageneric function defined for allatomic object typesA. The argument is pointer to a volatile atomic type to accept addresses of both non-volatile andvolatile (e.g. memory-mapped I/O) atomic objects, and volatile semantic is preserved when applying this operation to volatile atomic objects.C is the non-atomic type corresponding toA.
It is unspecified whether the name of a generic function is a macro or an identifier declared with external linkage. If a macro definition is suppressed in order to access an actual function (e.g. parenthesized like(atomic_load)(...)), or a program defines an external identifier with the name of a generic function, the behavior is undefined.
Contents |
| obj | - | pointer to the atomic object to access |
| order | - | the memory synchronization ordering for this operation |
The current value of the atomic variable pointed to byobj.
| stores a value in an atomic object (function)[edit] | |
C++ documentation foratomic_load,atomic_load_explicit | |
