How do I return a smart pointer?

So the best way to return a shared_ptr is to simply return by value: shared_ptr Foo() { return shared_ptr(/* acquire something */); }; This is a dead-obvious RVO opportunity for modern C++ compilers.

What is the smart pointer in C++?

A Smart Pointer is a wrapper class over a pointer with an operator like * and -> overloaded. The objects of the smart pointer class look like normal pointers. But, unlike Normal Pointers it can deallocate and free destroyed object memory.

When would you use a smart pointer?

Smart pointers are used to make sure that an object is deleted if it is no longer used (referenced). The unique_ptr<> template holds a pointer to an object and deletes this object when the unique_ptr<> object is deleted.

Should Shared_ptr be passed by reference?

In general, you should pass the shared pointer as a straight copy. This gives it its intended semantics: Every scope that contains a copy of the shared pointer keeps the object alive by virtue of its “share” in the ownership.

Are smart pointers thread safe?

I often have the question in my C++ seminars: Are smart pointers thread-safe? Yes, the control block is thread-safe; but no, the access to the resource is not thread-safe. That means, modifying the reference counter is an atomic operation and you have the guarantee that the resource will be deleted exactly once.

What is std :: Make_shared?

std::make_shared Allocates and constructs an object of type T passing args to its constructor, and returns an object of type shared_ptr that owns and stores a pointer to it (with a use count of 1). This function uses ::new to allocate storage for the object.

Should I use std :: move?

Q: When should it be used? A: You should use std::move if you want to call functions that support move semantics with an argument which is not an rvalue (temporary expression).