std::shared_ptr::use_count
From cppreference.com
< cpp | memory | shared ptr
| long use_count() const;
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||
Returns the number of different shared_ptr instances (this included) managing the current object. If there is no managed object, 0 is returned.
Contents |
[edit] Parameters
(none)
[edit] Return value
the number of shared_ptr instances managing the current object or 0 if there is no managed object.
[edit] Example
Run this code
#include <memory> #include <iostream> void fun(std::shared_ptr<int> sp) { std::cout << "fun: sp.use_count() == " << sp.use_count() << std::endl; } int main() { std::shared_ptr<int> sp1 {std::make_shared<int>(5)}; std::cout << "sp1.use_count() == " << sp1.use_count() << std::endl; fun(sp1); }
Output:
sp1.use_count() == 1 fun: sp.use_count() == 2
[edit] See also
checks whether the managed object is managed only by the current shared_ptr instance (public member function) |