I am reading about thread safety of various stl containers from this link Now I came across this point which states for C++11 only
Different elements in the same container can be modified concurrently by different threads, except for the elements of
std::vector<bool>
(for example, a vector ofstd::future
objects can be receiving values from multiple threads)
Does this mean if I have a method such as this which is being used by multiple threads simultaneously (notice the method does not have any locks)
void ChangeValue(int index , int value)
{
someVector[index] = value;
}
Is the above method safe. My understanding is that it is safe for C++11 only. However when I look at the other statement mentioned in the link
All const member functions can be called concurrently by different threads on the same container. In addition, the member functions begin(), end(), rbegin(), rend(), front(), back(), data(), find(), lower_bound(), upper_bound(), equal_range(), at(), and, except in associative containers, operator[], behave as const for the purposes of thread safety (that is, they can also be called concurrently by different threads on the same container). More generally, the C++ standard library functions do not modify objects unless those objects are accessible, directly or indirectly, via the function's non-const arguments, including the this pointer.
I come to the conclusion that in C++03 the above method can be safely used as well. Kindly let me know if my understanding is correct.
Aucun commentaire:
Enregistrer un commentaire