Class intrusive_ref

Class intrusive_ref_counter

boost::log::intrusive_ref_counter — A reference counter base class.

Synopsis

// In header: <boost/log/utility/intrusive_ref_counter.hpp>


class intrusive_ref_counter {
public:
  // construct/copy/destruct
  intrusive_ref_counter();
  intrusive_ref_counter(intrusive_ref_counter const &);
  intrusive_ref_counter& operator=(intrusive_ref_counter const &);
  ~intrusive_ref_counter();

  // public member functions
  unsigned long use_count() const;
};

Description

This base class can be used with user-defined classes to add support for intrusive_ptr. The class contains a thread-safe reference counter and a virtual destructor, which makes the derived class polymorphic. Upon releasing the last intrusive_ptr referencing the object derived from the intrusive_ref_counter class, operator delete is automatically called on the pointer to the object.

`intrusive_ref_counter` public construct/copy/destruct

```
intrusive_ref_counter();
```
Default constructor

Postconditions:
use_count() == 0

intrusive_ref_counter(intrusive_ref_counter const &);

Copy constructor

Postconditions:

use_count() == 0

```
intrusive_ref_counter& operator=(intrusive_ref_counter const &);
```
Assignment

Postconditions:
The reference counter is not modified after assignment
```
~intrusive_ref_counter();
```
Virtual destructor

`intrusive_ref_counter` public member functions

```
unsigned long use_count() const;
```
Returns:
The reference counter