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## Class null_mutex

boost::interprocess::null_mutex

## Synopsis

    // In header: <boost/interprocess/sync/null_mutex.hpp>

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

      // public member functions
      void lock();
      bool try_lock();
      bool timed_lock(const boost::posix_time::ptime &);
      void unlock();
      void lock_sharable();
      bool try_lock_sharable();
      bool timed_lock_sharable(const boost::posix_time::ptime &);
      void unlock_sharable();
      void lock_upgradable();
      bool try_lock_upgradable();
      bool timed_lock_upgradable(const boost::posix_time::ptime &);
      void unlock_upgradable();
      void unlock_and_lock_upgradable();
      void unlock_and_lock_sharable();
      void unlock_upgradable_and_lock_sharable();
      void unlock_upgradable_and_lock();
      bool try_unlock_upgradable_and_lock();
      bool timed_unlock_upgradable_and_lock(const boost::posix_time::ptime &);
      bool try_unlock_sharable_and_lock();
      bool try_unlock_sharable_and_lock_upgradable();
    };

## Description

Implements a mutex that simulates a mutex without doing any operation and simulates a successful operation.

### `null_mutex` public construct/copy/destruct

1.     null_mutex();

   Constructor. Empty.

2.     null_mutex& operator=(const null_mutex &);

   @ null_mutex(const null_mutex&);

3.     ~null_mutex();

   Destructor. Empty.

### `null_mutex` public member functions

1.     void lock();

   Simulates a mutex lock() operation. Empty function.

2.     bool try_lock();

   Simulates a mutex try_lock() operation. Equivalent to "return true;"

3.     bool timed_lock(const boost::posix_time::ptime &);

   Simulates a mutex timed_lock() operation. Equivalent to "return true;"

4.     void unlock();

   Simulates a mutex unlock() operation. Empty function.

5.     void lock_sharable();

   Simulates a mutex lock_sharable() operation. Empty function.

6.     bool try_lock_sharable();

   Simulates a mutex try_lock_sharable() operation. Equivalent to "return true;"

7.     bool timed_lock_sharable(const boost::posix_time::ptime &);

   Simulates a mutex timed_lock_sharable() operation. Equivalent to "return true;"

8.     void unlock_sharable();

   Simulates a mutex unlock_sharable() operation. Empty function.

9.     void lock_upgradable();

   Simulates a mutex lock_upgradable() operation. Empty function.

10.     bool try_lock_upgradable();

    Simulates a mutex try_lock_upgradable() operation. Equivalent to "return true;"

11.     bool timed_lock_upgradable(const boost::posix_time::ptime &);

    Simulates a mutex timed_lock_upgradable() operation. Equivalent to "return true;"

12.     void unlock_upgradable();

    Simulates a mutex unlock_upgradable() operation. Empty function.

13.     void unlock_and_lock_upgradable();

    Simulates unlock_and_lock_upgradable(). Empty function.

14.     void unlock_and_lock_sharable();

    Simulates unlock_and_lock_sharable(). Empty function.

15.     void unlock_upgradable_and_lock_sharable();

    Simulates unlock_upgradable_and_lock_sharable(). Empty function.

16.     void unlock_upgradable_and_lock();

    Simulates unlock_upgradable_and_lock(). Empty function.

17.     bool try_unlock_upgradable_and_lock();

    Simulates try_unlock_upgradable_and_lock(). Equivalent to "return true;"

18.     bool timed_unlock_upgradable_and_lock(const boost::posix_time::ptime &);

    Simulates timed_unlock_upgradable_and_lock(). Equivalent to "return true;"

19.     bool try_unlock_sharable_and_lock();

    Simulates try_unlock_sharable_and_lock(). Equivalent to "return true;"

20.     bool try_unlock_sharable_and_lock_upgradable();

    Simulates try_unlock_sharable_and_lock_upgradable(). Equivalent to "return true;"