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

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< cpp‎ | thread‎ | thread‎ | id

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operator==operator!=operator<operator<=operator>operator>=operator<=>

(until C++20)(until C++20)(until C++20)(until C++20)(until C++20)(C++20)

operator<<

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hash<std::thread::id>

formatter<std::thread::id>

(C++23)

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.

Contents

[edit] Parameters

ost - output stream to insert the data into

id - thread identifier

[edit] Return value

ost

[edit] Exceptions

May throw implementation-defined exceptions.

[edit] 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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