Standard library header <mutex> (C++11)

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<stdatomic.h>
 

This header is part of the thread support library.

Classes

(C++11)
provides basic mutual exclusion facility
(class)
provides mutual exclusion facility which implements locking with a timeout
(class)
provides mutual exclusion facility which can be locked recursively by the same thread
(class)
provides mutual exclusion facility which can be locked recursively
by the same thread and implements locking with a timeout
(class)
implements a strictly scope-based mutex ownership wrapper
(class template)
implements movable mutex ownership wrapper
(class template)
deadlock-avoiding RAII wrapper for multiple mutexes
(class template)
tag type used to specify locking strategy
(class)
(C++11)
helper object to ensure that call_once invokes the function only once
(class)

Constants

tag constants used to specify locking strategy
(constant)

Functions

(C++11)
attempts to obtain ownership of mutexes via repeated calls to try_lock
(function template)
(C++11)
locks specified mutexes, blocks if any are unavailable
(function template)
(C++11)
invokes a function only once even if called from multiple threads
(function template)
specialization of std::swap for unique_lock
(function template)

Synopsis

namespace std {
  class mutex;
  class recursive_mutex;
  class timed_mutex;
  class recursive_timed_mutex;
 
  struct defer_lock_t { explicit defer_lock_t() = default; };
  struct try_to_lock_t { explicit try_to_lock_t() = default; };
  struct adopt_lock_t { explicit adopt_lock_t() = default; };
 
  inline constexpr defer_lock_t  defer_lock { };
  inline constexpr try_to_lock_t try_to_lock { };
  inline constexpr adopt_lock_t  adopt_lock { };
 
  template<class Mutex> class lock_guard;
  template<class... MutexTypes> class scoped_lock;
  template<class Mutex> class unique_lock;
 
  template<class Mutex>
    void swap(unique_lock<Mutex>& x, unique_lock<Mutex>& y) noexcept;
 
  template<class L1, class L2, class... L3> int try_lock(L1&, L2&, L3&...);
  template<class L1, class L2, class... L3> void lock(L1&, L2&, L3&...);
 
  struct once_flag;
 
  template<class Callable, class... Args>
    void call_once(once_flag& flag, Callable&& func, Args&&... args);
}

Class std::mutex

namespace std {
  class mutex {
  public:
    constexpr mutex() noexcept;
    ~mutex();
 
    mutex(const mutex&) = delete;
    mutex& operator=(const mutex&) = delete;
 
    void lock();
    bool try_lock();
    void unlock();
 
    using native_handle_type = /* implementation-defined */;
    native_handle_type native_handle();
  };
}

Class std::recursive_mutex

namespace std {
  class recursive_mutex {
  public:
    recursive_mutex();
    ~recursive_mutex();
 
    recursive_mutex(const recursive_mutex&) = delete;
    recursive_mutex& operator=(const recursive_mutex&) = delete;
 
    void lock();
    bool try_lock() noexcept;
    void unlock();
 
    using native_handle_type = /* implementation-defined */;
    native_handle_type native_handle();
  };
}

Class std::timed_mutex

namespace std {
  class timed_mutex {
  public:
    timed_mutex();
    ~timed_mutex();
 
    timed_mutex(const timed_mutex&) = delete;
    timed_mutex& operator=(const timed_mutex&) = delete;
 
    void lock();    // blocking
    bool try_lock();
    template<class Rep, class Period>
      bool try_lock_for(const chrono::duration<Rep, Period>& rel_time);
    template<class Clock, class Duration>
      bool try_lock_until(const chrono::time_point<Clock, Duration>& abs_time);
    void unlock();
 
    using native_handle_type = /* implementation-defined */;
    native_handle_type native_handle();
  };
}

Class std::recursive_timed_mutex

namespace std {
  class recursive_timed_mutex {
  public:
    recursive_timed_mutex();
    ~recursive_timed_mutex();
 
    recursive_timed_mutex(const recursive_timed_mutex&) = delete;
    recursive_timed_mutex& operator=(const recursive_timed_mutex&) = delete;
 
    void lock();    // blocking
    bool try_lock() noexcept;
    template<class Rep, class Period>
      bool try_lock_for(const chrono::duration<Rep, Period>& rel_time);
    template<class Clock, class Duration>
      bool try_lock_until(const chrono::time_point<Clock, Duration>& abs_time);
    void unlock();
 
    using native_handle_type = /* implementation-defined */;
    native_handle_type native_handle();
  };
}

Class template std::lock_guard

namespace std {
  template<class Mutex>
  class lock_guard {
  public:
    using mutex_type = Mutex;
 
    explicit lock_guard(mutex_type& m);
    lock_guard(mutex_type& m, adopt_lock_t);
    ~lock_guard();
 
    lock_guard(const lock_guard&) = delete;
    lock_guard& operator=(const lock_guard&) = delete;
 
  private:
    mutex_type& pm;             // exposition only
  };
}

Class template std::scoped_lock

namespace std {
  template<class... MutexTypes>
  class scoped_lock {
  public:
    using mutex_type = Mutex;   // If MutexTypes... consists of the single type Mutex
 
    explicit scoped_lock(MutexTypes&... m);
    explicit scoped_lock(adopt_lock_t, MutexTypes&... m);
    ~scoped_lock();
 
    scoped_lock(const scoped_lock&) = delete;
    scoped_lock& operator=(const scoped_lock&) = delete;
 
  private:
    tuple<MutexTypes&...> pm;   // exposition only
  };
}

Class template std::unique_lock

namespace std {
  template<class Mutex>
  class unique_lock {
  public:
    using mutex_type = Mutex;
 
    // construct/copy/destroy
    unique_lock() noexcept;
    explicit unique_lock(mutex_type& m);
    unique_lock(mutex_type& m, defer_lock_t) noexcept;
    unique_lock(mutex_type& m, try_to_lock_t);
    unique_lock(mutex_type& m, adopt_lock_t);
    template<class Clock, class Duration>
      unique_lock(mutex_type& m, const chrono::time_point<Clock, Duration>& abs_time);
    template<class Rep, class Period>
      unique_lock(mutex_type& m, const chrono::duration<Rep, Period>& rel_time);
    ~unique_lock();
 
    unique_lock(const unique_lock&) = delete;
    unique_lock& operator=(const unique_lock&) = delete;
 
    unique_lock(unique_lock&& u) noexcept;
    unique_lock& operator=(unique_lock&& u);
 
    // locking
    void lock();
    bool try_lock();
 
    template<class Rep, class Period>
      bool try_lock_for(const chrono::duration<Rep, Period>& rel_time);
    template<class Clock, class Duration>
      bool try_lock_until(const chrono::time_point<Clock, Duration>& abs_time);
 
    void unlock();
 
    // modifiers
    void swap(unique_lock& u) noexcept;
    mutex_type* release() noexcept;
 
    // observers
    bool owns_lock() const noexcept;
    explicit operator bool () const noexcept;
    mutex_type* mutex() const noexcept;
 
  private:
    mutex_type* pm;             // exposition only
    bool owns;                  // exposition only
  };
 
  template<class Mutex>
    void swap(unique_lock<Mutex>& x, unique_lock<Mutex>& y) noexcept;
}

Class std::once_flag

namespace std {
  struct once_flag {
    constexpr once_flag() noexcept;
 
    once_flag(const once_flag&) = delete;
    once_flag& operator=(const once_flag&) = delete;
  };
}