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std::jthread::get_id

From cppreference.com
< cpp‎ | thread‎ | jthread
 
 
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[[nodiscard]] std::jthread::id get_id() const noexcept;
(since C++20)

Returns a value of std::jthread::id (which is a type alias for std::thread::id) identifying the thread associated with *this.

Contents

[edit] Parameters

(none)

[edit] Return value

A value of type std::jthread::id identifying the thread associated with *this. If there is no thread associated, default constructed std::jthread::id is returned.

[edit] Example

#include <chrono>
#include <iostream>
#include <thread>
 
void foo()
{
    std::this_thread::sleep_for(std::chrono::seconds(1));
}
 
int main()
{
    std::jthread t1(foo);
    std::jthread::id t1_id = t1.get_id();
 
    std::jthread t2(foo);
    std::jthread::id t2_id = t2.get_id();
 
    std::cout << "t1's id: " << t1_id << '\n';
    std::cout << "t2's id: " << t2_id << '\n';
 
    t1.join();
    t2.join();
 
    std::cout << "t1's id after join: " << t1.get_id() << '\n';
    std::cout << "t2's id after join: " << t2.get_id() << '\n';
}

Possible output:

t1's id: 140146221688576
t2's id: 140146213295872
t1's id after join: thread::id of a non-executing thread
t2's id after join: thread::id of a non-executing thread

[edit] See also

represents the id of a thread
(public member class of std::thread) [edit]
checks whether the thread is joinable, i.e. potentially running in parallel context
(public member function) [edit]