Smart Pointer in C++
Smart pointers in C++ are powerful tools that help manage memory automatically, reducing the risk of memory leaks and dangling pointers.
Instead of manually calling delete to free memory, smart pointers take care of it when the object is no longer needed.
Here’s a breakdown of the main types and how they work:
🧠 What Are Smart Pointers?
Smart pointers are class templates in the C++ Standard Library that wrap raw pointers and manage their lifetime using RAII (Resource Acquisition Is Initialization). When a smart pointer goes out of scope, it automatically deletes the object it points to.
🔑 Types of Smart Pointers
| Type | Ownership Model | Use Case Example |
|---|---|---|
std::unique_ptr |
Sole ownership (non-copyable) | Managing exclusive resources |
std::shared_ptr |
Shared ownership (reference counted) | Multiple owners of the same resource |
std::weak_ptr |
Non-owning reference to shared_ptr |
Avoiding cyclic references in shared data |
📌 Quick Examples
std::unique_ptr
#include <memory>
std::unique_ptr<int> ptr = std::make_unique<int>(42);
// Automatically deleted when ptr goes out of scope
std::shared_ptr
#include <memory>
std::shared_ptr<int> ptr1 = std::make_shared<int>(42);
std::shared_ptr<int> ptr2 = ptr1; // Both share ownership
std::weak_ptr
#include <memory>
std::shared_ptr<int> shared = std::make_shared<int>(42);
std::weak_ptr<int> weak = shared; // Doesn't affect reference count
🧩 Why Use Smart Pointers?
- Automatic memory management
- Exception safety
- Cleaner, more maintainable code
- No need to manually
deleteobjects
Note:
Current version of this post is generated partially using generative AI.