std::jthread::get_id

 

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std::jthread

Member functions

jthread::jthread

jthread::~jthread

jthread::operator=

Observers

jthread::joinable

jthread::get_id

jthread::native_handle

jthread::hardware_concurrency

Operations

jthread::join

jthread::detach

jthread::swap

Stop token handling

jthread::get_stop_source

jthread::get_stop_token

jthread::request_stop

Non-member functions

swap(std::jthread)

 

[[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.

Parameters

(none)

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.

Example

Run this code

#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

See also

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