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Standard library header <mutex>

From cppreference.com
< cpp‎ | header
 
 
 

This header is part of the thread support library.

Contents

Classes

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

Constants

tag constants used to specify locking strategy
(constant) [edit]

Functions

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

[edit] 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);
}

[edit] 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();
  };
}

[edit] 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();
  };
}

[edit] 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();
  };
}

[edit] 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();
  };
}

[edit] 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
  };
}

[edit] 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
  };
}

[edit] 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;
}

[edit] 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;
  };
}