std::jthread:: get_id

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Concurrency support library
Threads
(C++11)
(C++20)
this_thread namespace
(C++11)
(C++11)
Cooperative cancellation
Mutual exclusion
Generic lock management
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(C++11)
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(C++20)
(C++20)
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(C++11)
(C++11)
(C++11)
Safe Reclamation
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(C++11)
(C++20)
Initialization of atomic types
(C++11) (deprecated in C++20)
(C++11) (deprecated in C++20)
Memory ordering
Free functions for atomic operations
Free functions for atomic flags
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

#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

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