std::enable_shared_from_this::shared_from_this - cppreference.com

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# std::enable_shared_from_this::shared_from_this

From cppreference.com
< cpp‎ | memory‎ | enable shared from this

shared_ptr<T> shared_from_this(); | (1) |
shared_ptr<T const> shared_from_this() const; | (2) |

Returns a std::shared_ptr<T> that shares ownership of *this with all existing std::shared_ptr<T> that refer to *this.

### [edit] Notes

Before calling `shared_from_this`, there should be at least one std::shared_ptr<T> `p` that owns *this.

### [edit] Return value

std::shared_ptr<T> that shares ownership of *this with pre-existing std::shared_ptr<T>s

### [edit] Example

Run this code

    #include <iostream>
    #include <memory>

    struct Foo : public std::enable_shared_from_this<Foo> {
        Foo() { std::cout << "Foo::Foo\n"; }
        ~Foo() { std::cout << "Foo::~Foo\n"; }
        std::shared_ptr<Foo> getFoo() { return shared_from_this(); }
    };

    int main() {
        Foo *f = new Foo;
        std::shared_ptr<Foo> pf1;

        {
            std::shared_ptr<Foo> pf2(f);
            pf1 = pf2->getFoo();  // shares ownership of object with pf2
        }

        std::cout << "pf2 is gone\n";
    }

Output:

    Foo::Foo
    pf2 is gone
    Foo::~Foo

### [edit] See also

shared_ptr (C++11) | smart pointer with shared object ownership semantics (class template) [edit]

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