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## Class named_recursive_mutex

boost::interprocess::named_recursive_mutex

## Synopsis

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

    class named_recursive_mutex {
    public:
      // types
      typedef unspecified construct_func_t;

      // construct/copy/destruct
      named_recursive_mutex();
      named_recursive_mutex(const named_recursive_mutex &);
      named_recursive_mutex(create_only_t, const char *,
                            const permissions & = permissions());
      named_recursive_mutex(open_or_create_t, const char *,
                            const permissions & = permissions());
      named_recursive_mutex(open_only_t, const char *);
      named_recursive_mutex& operator=(const named_recursive_mutex &);
      ~named_recursive_mutex();

      // friend functions
      friend class detail::interprocess_tester();

      // public member functions
      void unlock();
      void lock();
      bool try_lock();
      bool timed_lock(const boost::posix_time::ptime &);
      void dont_close_on_destruction();
      interprocess_recursive_mutex * mutex() const;

      // public static functions
      static bool remove(const char *);
      unspecified m_shmem;
    };

## Description

A recursive mutex with a global name, so it can be found from different processes. This mutex can't be placed in shared memory, and each process should have it's own named_recursive_mutex.

### `named_recursive_mutex` public construct/copy/destruct

1.     named_recursive_mutex();

   @ //Non-copyable

2.     named_recursive_mutex(const named_recursive_mutex &);

3.     named_recursive_mutex(create_only_t create_only, const char * name,
                             const permissions & perm = permissions());

   Creates a global recursive_mutex with a name. If the recursive_mutex can't be created throws interprocess_exception

4.     named_recursive_mutex(open_or_create_t open_or_create, const char * name,
                             const permissions & perm = permissions());

   Opens or creates a global recursive_mutex with a name. If the recursive_mutex is created, this call is equivalent to named_recursive_mutex(create_only_t, ... ) If the recursive_mutex is already created, this call is equivalent named_recursive_mutex(open_only_t, ... ) Does not throw

5.     named_recursive_mutex(open_only_t open_only, const char * name);

   Opens a global recursive_mutex with a name if that recursive_mutex is previously created. If it is not previously created this function throws interprocess_exception.

6.     named_recursive_mutex& operator=(const named_recursive_mutex &);

7.     ~named_recursive_mutex();

   @

   Destroys *this and indicates that the calling process is finished using the resource. The destructor function will deallocate any system resources allocated by the system for use by this process for this resource. The resource can still be opened again calling the open constructor overload. To erase the resource from the system use remove().

### `named_recursive_mutex` friend functions

1.     friend class detail::interprocess_tester();

   @ private:

### `named_recursive_mutex` public member functions

1.     void unlock();

   Unlocks a previously locked named_recursive_mutex.

2.     void lock();

   Locks named_recursive_mutex, sleeps when named_recursive_mutex is already locked. Throws interprocess_exception if a severe error is found.

3.     bool try_lock();

   Tries to lock the named_recursive_mutex, returns false when named_recursive_mutex is already locked, returns true when success. Throws interprocess_exception if a severe error is found.

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

   Tries to lock the named_recursive_mutex until time abs_time, Returns false when timeout expires, returns true when locks. Throws interprocess_exception if a severe error is found

5.     void dont_close_on_destruction();

6.     interprocess_recursive_mutex * mutex() const;

### `named_recursive_mutex` public static functions

1.     static bool remove(const char * name);

   Erases a named recursive mutex from the system