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std::atomic::is_lock_free(3)   C++ Standard Libary  std::atomic::is_lock_free(3)

NAME
     std::atomic::is_lock_free - std::atomic::is_lock_free

Synopsis
	bool is_lock_free() const noexcept;	     (1) (since C++11)
	bool is_lock_free() const volatile noexcept; (2) (since C++11)

	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 may  be  implemented  using
     mutexes or
	other locking operations, rather than using the lock-free atomic CPU in-
     structions.
	Atomic	types  are  also allowed to be sometimes lock-free, e.g. if only
     aligned memory
	accesses are naturally atomic on a given  architecture,  misaligned  ob-
     jects of the
	same type have to use locks.

	The C++ standard recommends (but does not require) that lock-free atomic
     operations
	are  also  address-free,  that	is,  suitable  for communication between
     processes using
	shared memory.

Example
     // Run this code

      #include <atomic>
      #include <iostream>
      #include <utility>

      struct A { int a[100]; };
      struct B { int x, y; };

      int main()
      {
	  std::cout << std::boolalpha
		    << "std::atomic<A> is lock free? "
		    << std::atomic<A>{}.is_lock_free() << '\n'
		    << "std::atomic<B> is lock free? "
		    << std::atomic<B>{}.is_lock_free() << '\n';
      }

Possible output:
      std::atomic<A> is lock free? false
      std::atomic<B> is lock free? true

See also
	atomic_is_lock_free		     checks if the atomic type's  opera-
     tions are
	(C++11) 			     lock-free
					     (function template)
					     specializes atomic operations for
	atomic_is_lock_free(std::shared_ptr) std::shared_ptr
					     (function template)
	is_always_lock_free		      indicates  that the type is always
     lock-free
	[static] (C++17)		     (public static member constant)

http://cppreference.com 	   2024.06.10	    std::atomic::is_lock_free(3)
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