std::this_thread::get_id

 

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Defined in header <thread>
std::thread::id get_id() noexcept;		(since C++11)

Returns the id of the current thread.

Parameters

(none)

Return value

id of the current thread

Example

Run this code

#include <iostream>
#include <thread>
#include <chrono>
#include <mutex>
 
std::mutex g_display_mutex;
 
void foo()
{
    std::thread::id this_id = std::this_thread::get_id();
 
    g_display_mutex.lock();
    std::cout << "thread " << this_id << " sleeping...\n";
    g_display_mutex.unlock();
 
    std::this_thread::sleep_for(std::chrono::seconds(1));
}
 
int main()
{
    std::thread t1(foo);
    std::thread t2(foo);
 
    t1.join();
    t2.join();
}

Possible output:

thread 0x2384b312 sleeping...
thread 0x228a10fc sleeping...

See also

get_id	returns the id of the thread (public member function of std::thread)
C documentation for thrd_current