atomic_load, atomic_load_explicit
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                    | Defined in header  <stdatomic.h> | ||
| C atomic_load( const volatile A* obj ); | (1) | (since C11) | 
| C atomic_load_explicit( const volatile A* obj, memory_order order ); | (2) | (since C11) | 
Atomically loads and returns the current value of the atomic variable pointed to by obj. The operation is atomic read operation. 
The first version orders memory accesses according to memory_order_seq_cst, the second version orders memory accesses according to order. order must be one of memory_order_relaxed, memory_order_consume, memory_order_acquire or memory_order_seq_cst. Otherwise the behavior is undefined.
This is a generic function defined for all atomic object types A. The argument is pointer to a volatile atomic type to accept addresses of both non-volatile and volatile (e.g. memory-mapped I/O) atomic variables.C is the non-atomic type corresponding to A.
Parameters
| obj | - | pointer to the atomic object to access | 
| order | - | the memory synchronization ordering for this operation | 
Return value
The current value of the atomic variable pointed to by obj.
References
- C11 standard (ISO/IEC 9899:2011):
- 7.17.7.2 The atomic_load generic functions (p: 282)
 
See also
| stores a value in an atomic object (function) | |
| C++ documentation for atomic_load, atomic_load_explicit | |