Smart pointer

In computer science, a smart pointer is an abstract data type that simulates a pointer while providing added features, such as automatic memory management or bounds checking. Such features are intended to reduce bugs caused by the misuse of pointers, while retaining efficiency. Smart pointers typically keep track of the memory they point to, and may also be used to manage other resources, such as network connections and file handles. Smart pointers were first popularized in the programming language C++ during the first half of the 1990s as rebuttal to criticisms of C++'s lack of automatic garbage collection. In previous versions of Rust, there was also a that wrapped around raw non-null .

It is possible to use "smart void pointers" using <code>std::unique_ptr</code>, using its second template parameter <code>Deleter</code>, which stores a type of a deallocator.

using std::unique_ptr;

struct MyDeleter {

void operator()(void* p) const {

delete static_cast<int*>(p);

}

};

int main() {

unique_ptr<void, MyDeleter> myPointer(new int(42), MyDeleter());

}

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Shared pointers and weak pointers

C++11 introduces and , defined in the header .

Hazard pointers

Starting in C++26, there is a new pointer defined in , the hazard pointer (). It is a single-writer multi-reader pointer that can be owned by at most one thread at any point in time.

The hazard pointer had existed already previously in some third-party libraries.

Other types of smart pointers

There are other types of smart pointers (which are not in the C++ standard) implemented on popular C++ libraries or custom STL, some examples include the intrusive pointer.

References

External links

countptr.hpp. The C++ Standard Library - A Tutorial and Reference by Nicolai M. Josuttis
Boost Smart Pointers
Smart Pointers in Delphi
Smart Pointers in Rust
Smart Pointers in Modern C++

Shared pointers and weak pointers

Hazard pointers

Other types of smart pointers

See also

References

Further reading

External links