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std::shared_ptr<T>::get

Declarations

Until C++17
T* get() const noexcept;
Since C++17
element_type* get() const noexcept;

Returns the stored pointer.

Parameters

(none)

Return value

The stored pointer.

Notes

A shared_ptr may share ownership of an object while storing a pointer to another object. get() returns the stored pointer, not the managed pointer.

Example

#include <iostream>
#include <memory>
#include <string_view>

int main()
{
auto output = [](std::string_view msg, int const* pInt) {
std::cout
<< msg << *pInt
<< " in " << pInt
<< "\n";
};

int* pInt = new int(42);
std::shared_ptr<int> pShared = std::make_shared<int>(42);

output("Naked pointer ", pInt);
// output("Shared pointer ", pShared); // compiler error
output("Shared pointer with get() ", pShared.get());

delete pInt;


std::cout << "\nThe shared_ptr's aliasing constructor demo.\n";
struct Base1 { int i1{}; };
struct Base2 { int i2{}; };
struct Derived : Base1, Base2 { int i3{}; };

std::shared_ptr<Derived> p(new Derived());
std::shared_ptr<Base2> q(p, static_cast<Base2*>(p.get()));
std::cout
<< "q shares ownership with p, but points to Base2 subobject:\n"
<< "p.get(): " << p.get() << '\n'
<< "q.get(): " << q.get() << '\n'
<< "&(p->i1): " << &(p->i1) << '\n'
<< "&(p->i2): " << &(p->i2) << '\n'
<< "&(p->i3): " << &(p->i3) << '\n'
<< "&(q->i2): " << &(q->i2) << '\n';
}
Possible Result
Naked pointer 42 in 0xacac20
Shared pointer with get() 42 in 0xacac50

The shared_ptr's aliasing constructor demo.
q shares ownership with p, but points to Base2 subobject:
p.get(): 0xacac20
q.get(): 0xacac24
&(p->i1): 0xacac20
&(p->i2): 0xacac24
&(p->i3): 0xacac28
&(q->i2): 0xacac24

std::shared_ptr<T>::get

Declarations

Until C++17
T* get() const noexcept;
Since C++17
element_type* get() const noexcept;

Returns the stored pointer.

Parameters

(none)

Return value

The stored pointer.

Notes

A shared_ptr may share ownership of an object while storing a pointer to another object. get() returns the stored pointer, not the managed pointer.

Example

#include <iostream>
#include <memory>
#include <string_view>

int main()
{
auto output = [](std::string_view msg, int const* pInt) {
std::cout
<< msg << *pInt
<< " in " << pInt
<< "\n";
};

int* pInt = new int(42);
std::shared_ptr<int> pShared = std::make_shared<int>(42);

output("Naked pointer ", pInt);
// output("Shared pointer ", pShared); // compiler error
output("Shared pointer with get() ", pShared.get());

delete pInt;


std::cout << "\nThe shared_ptr's aliasing constructor demo.\n";
struct Base1 { int i1{}; };
struct Base2 { int i2{}; };
struct Derived : Base1, Base2 { int i3{}; };

std::shared_ptr<Derived> p(new Derived());
std::shared_ptr<Base2> q(p, static_cast<Base2*>(p.get()));
std::cout
<< "q shares ownership with p, but points to Base2 subobject:\n"
<< "p.get(): " << p.get() << '\n'
<< "q.get(): " << q.get() << '\n'
<< "&(p->i1): " << &(p->i1) << '\n'
<< "&(p->i2): " << &(p->i2) << '\n'
<< "&(p->i3): " << &(p->i3) << '\n'
<< "&(q->i2): " << &(q->i2) << '\n';
}
Possible Result
Naked pointer 42 in 0xacac20
Shared pointer with get() 42 in 0xacac50

The shared_ptr's aliasing constructor demo.
q shares ownership with p, but points to Base2 subobject:
p.get(): 0xacac20
q.get(): 0xacac24
&(p->i1): 0xacac20
&(p->i2): 0xacac24
&(p->i3): 0xacac28
&(q->i2): 0xacac24