std::thread::get_id

 

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std::thread

Member classes

thread::id

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thread::thread

thread::~thread

thread::operator=

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thread::joinable

thread::get_id

thread::native_handle

thread::hardware_concurrency

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thread::join

thread::detach

thread::swap

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swap(std::thread) (C++11)

 

std::thread::id get_id() const noexcept;		(since C++11)

Returns a value of std::thread::id identifying the thread associated with *this.

Parameters

(none)

Return value

A value of type std::thread::id identifying the thread associated with *this. If there is no thread associated, default constructed std::thread::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::thread t1(foo);
    std::thread::id t1_id = t1.get_id();
 
    std::thread t2(foo);
    std::thread::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)
joinable	checks whether the thread is joinable, i.e. potentially running in parallel context (public member function)