operator<< (std::thread::id)

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Defined in header <thread>
template < class CharT, class Traits >

std:: basic_ostream < CharT,Traits > &

operator << ( std:: basic_ostream < CharT,Traits > & ost, std:: thread :: id id ) ;
(since C++11)

Writes a textual representation of a thread identifier id to the output stream ost .

If two thread identifiers compare equal, they have identical textual representations; if they do not compare equal, their representations are distinct.

Parameters

ost - output stream to insert the data into
id - thread identifier

Return value

ost

Exceptions

May throw implementation-defined exceptions.

Example

Run this code 
#include <chrono>
#include <iostream>
#include <thread>
using namespace std::chrono;
 
int main()
{
    std::thread t1([]{ std::this_thread::sleep_for(256ms); });
    std::thread t2([]{ std::this_thread::sleep_for(512ms); });
 
    std::clog << t1.get_id() << '\n' << t2.get_id() << '\n';
 
    t1.join();
    t2.join();
}

Possible output: 

141592653589793
141421356237309
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