Which C Smart Pointer Should I Use?

Understanding Smart Pointers in C : When to Use Which Type

Smart pointers are essential tools in modern C programming for managing object ownership and resource lifetime. The emergence of C 11 and Boost libraries has introduced a diverse range of smart pointer types, raising the question of which one to use in different scenarios.

Shared Ownership

For shared resource ownership, std::shared_ptr and std::weak_ptr are recommended. Shared_ptr allows multiple owners to share a resource, while weak_ptr provides a non-owning reference to observe the resource without affecting its lifetime. Boost also offers shared_array as an alternative to std::shared_ptr const>.

Unique Ownership

std::unique_ptr is the default choice for unique ownership, offering several advantages over Boost's scoped_ptr. Unique_ptr supports custom deleters, is movable, and is compatible with STL containers. Boost provides scoped_array as an array version of scoped_ptr, which has been standardized in C 11.

No Ownership

Raw pointers or references should be used for non-owning references to resources that outlive the referencing object/scope. Raw pointers allow nullability and resettability, while references are preferred for immutability.

Boost Smart Pointers

Boost provides additional smart pointer types, such as intrusive_ptr, which is useful for adopting reference-counted management from existing resources. However, these types have not been standardized in C 11.

Deprecation

std::auto_ptr is now deprecated in C 11 in favor of unique_ptr, which offers enhanced functionality.

The above is the detailed content of Which C Smart Pointer Should I Use?. For more information, please follow other related articles on the PHP Chinese website!