Standard library header <condition_variable>

 

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Language support <cfloat> <climits> <compare> (C++20) <coroutine> (C++20) <csetjmp> <csignal> <cstdarg> <cstddef> <cstdint> (C++11) <cstdlib> <exception> <initializer_list> (C++11)    <limits> <new> <source_location> (C++20) <stdfloat> (C++23) <typeinfo> <version> (C++20) Concepts <concepts> (C++20) Diagnostics <cassert> <cerrno> <debugging> (C++26) <stacktrace> (C++23) <stdexcept> <system_error> (C++11) Memory management <memory> <memory_resource> (C++17) <scoped_allocator> (C++11) Metaprogramming <type_traits> (C++11) <ratio> (C++11)

General utilities <any> (C++17) <bitset> <bit> (C++20) <charconv> (C++17) <expected> (C++23) <format> (C++20) <functional> <optional> (C++17) <tuple> (C++11) <typeindex> (C++11) <utility> <variant> (C++17) Containers <array> (C++11) <deque> <flat_map> (C++23) <flat_set> (C++23) <forward_list> (C++11) <inplace_vector> (C++26)    <list> <map> <mdspan> (C++23) <queue> <set> <span> (C++20) <stack> <unordered_map> (C++11) <unordered_set> (C++11) <vector> Iterators <iterator> Ranges <generator> (C++23) <ranges> (C++20)

Algorithms <algorithm> <numeric> Strings <cctype> <cstring> <cuchar> (C++11) <cwchar> <cwctype> <string_view> (C++17) <string> Text processing <clocale> <codecvt> (C++11/17/26*) <locale> <regex> (C++11) <text_encoding> (C++26)    Numerics <cfenv> (C++11) <cmath> <complex> <linalg> (C++26) <numbers> (C++20) <random> (C++11) <valarray> Time <chrono> (C++11) <ctime> C compatibility <ccomplex> (C++11/17/20*) <ciso646> (until C++20) <cstdalign> (C++11/17/20*) <cstdbool> (C++11/17/20*) <ctgmath> (C++11/17/20*)

Input/output <cinttypes> (C++11) <cstdio> <filesystem> (C++17) <fstream> <iomanip> <iosfwd> <iostream> <ios> <istream> <ostream> <print> (C++23) <spanstream> (C++23) <sstream> <streambuf> <strstream> (C++98/26*) <syncstream> (C++20) Concurrency support <atomic> (C++11) <barrier> (C++20) <condition_variable> (C++11) <future> (C++11) <hazard_pointer> (C++26) <latch> (C++20) <mutex> (C++11) <rcu> (C++26) <semaphore> (C++20) <shared_mutex> (C++14) <stdatomic.h> (C++23) <stop_token> (C++20) <thread> (C++11) Execution support <execution> (C++17)

 

This header is part of the thread support library.

Classes
condition_variable (C++11)	provides a condition variable associated with a std::unique_lock (class)
condition_variable_any (C++11)	provides a condition variable associated with any lock type (class)
cv_status (C++11)	lists the possible results of timed waits on condition variables (enum)
Functions
notify_all_at_thread_exit (C++11)	schedules a call to notify_all to be invoked when this thread is completely finished (function)

Synopsis

namespace std {
 
    class condition_variable;
    class condition_variable_any;
 
    void notify_all_at_thread_exit(condition_variable& cond, unique_lock<mutex> lk);
 
    enum class cv_status {
        no_timeout,
        timeout
    };
}

Class std::condition_variable

class condition_variable {
 public:
    condition_variable();
    ~condition_variable();
    condition_variable(const condition_variable&) = delete;
    condition_variable& operator=(const condition_variable&) = delete;
 
    void notify_one() noexcept;
    void notify_all() noexcept;
    void wait(unique_lock<mutex>& lock);
    template <class Predicate>
        void wait(unique_lock<mutex>& lock, Predicate pred);
    template <class Clock, class Duration>
        cv_status wait_until(unique_lock<mutex>& lock,
                             const chrono::time_point<Clock, Duration>& abs_time);
    template <class Clock, class Duration, class Predicate>
        bool wait_until(unique_lock<mutex>& lock,
                        const chrono::time_point<Clock, Duration>& abs_time,
                        Predicate pred);
    template <class Rep, class Period>
        cv_status wait_for(unique_lock<mutex>& lock,
                           const chrono::duration<Rep, Period>& rel_time);
    template <class Rep, class Period, class Predicate>
        bool wait_for(unique_lock<mutex>& lock,
                      const chrono::duration<Rep, Period>& rel_time,
                      Predicate pred);
 
    typedef implementation-defined native_handle_type;
    native_handle_type native_handle();
};

Class std::condition_variable_any

class condition_variable_any {
 public:
    condition_variable_any();
    ~condition_variable_any();
    condition_variable_any(const condition_variable_any&) = delete;
    condition_variable_any& operator=(const condition_variable_any&) = delete;
 
    void notify_one() noexcept;
    void notify_all() noexcept;
    template <class Lock>
        void wait(Lock& lock);
    template <class Lock, class Predicate>
        void wait(Lock& lock, Predicate pred);
    template <class Lock, class Clock, class Duration>
        cv_status wait_until(Lock& lock,
                             const chrono::time_point<Clock, Duration>& abs_time);
    template <class Lock, class Clock, class Duration, class Predicate>
        bool wait_until(Lock& lock,
                        const chrono::time_point<Clock, Duration>& abs_time,
                        Predicate pred);
    template <class Lock, class Rep, class Period>
        cv_status wait_for(Lock& lock,
                           const chrono::duration<Rep, Period>& rel_time);
    template <class Lock, class Rep, class Period, class Predicate>
        bool wait_for(Lock& lock,
                      const chrono::duration<Rep, Period>& rel_time,
                      Predicate pred);
};