Standard library header <barrier> (C++20)

 

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<cstddef> <cstdlib> <version> (C++20) <limits> <climits>	<cfloat> <cstdint> (C++11) <stdfloat> (C++23) <new> <typeinfo>	<source_location> (C++20) <exception> <initializer_list> (C++11) <compare> (C++20)	<coroutine> (C++20) <csignal> <csetjmp> <cstdarg>
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<type_traits> (C++11)	<ratio> (C++11)
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<utility> <tuple> (C++11) <optional> (C++17) <variant> (C++17)	<any> (C++17) <debugging> (C++26) <expected> (C++23) <bitset>	<functional> <typeindex> (C++11) <execution> (C++17)	<charconv> (C++17) <format> (C++20) <bit> (C++20)
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<iosfwd> <iostream> <ios> <streambuf>	<istream> <ostream> <iomanip> <print> (C++23)	<sstream> <spanstream> (C++23) <fstream> <syncstream> (C++20)	<filesystem> (C++17) <cstdio> <cinttypes> (C++11) <strstream> (C++98/26*)
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<stop_token> (C++20) <thread> (C++11) <atomic> (C++11) <rcu> (C++26)	<stdatomic.h> (C++23) <mutex> (C++11) <shared_mutex> (C++14)	<condition_variable> (C++11)   <semaphore> (C++20) <latch> (C++20)	<barrier> (C++20) <future> (C++11) <hazard_pointer> (C++26)
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<cstdbool> (C++11/17/20*)   <ccomplex> (C++11/17/20*)	<ctgmath> (C++11/17/20*)	<cstdalign> (C++11/17/20*)	<ciso646> (until C++20)

 

This header is part of the thread support library.

Classes
barrier (C++20)	reusable thread barrier (class template)

Synopsis

namespace std {
  template<class CompletionFunction = /* see description */>
    class barrier;
}

Class template std::barrier

namespace std {
  template<class CompletionFunction = /* see description */>
  class barrier {
  public:
    using arrival_token =  /* see description */;
 
    static constexpr ptrdiff_t max() noexcept;
 
    constexpr explicit barrier(ptrdiff_t expected,
                               CompletionFunction f = CompletionFunction());
    ~barrier();
 
    barrier(const barrier&) = delete;
    barrier& operator=(const barrier&) = delete;
 
    [[nodiscard]] arrival_token arrive(ptrdiff_t update = 1);
    void wait(arrival_token&& arrival) const;
 
    void arrive_and_wait();
    void arrive_and_drop();
 
  private:
    CompletionFunction completion;      // exposition only
  };
}