Blocks the current thread until the thread identified by *this finishes its execution.

The completion of the thread identified by *this synchronizes with the corresponding successful return from join().

No synchronization is performed on *this itself. Concurrently calling join() on the same jthread object from multiple threads constitutes a data race that results in undefined behavior.

Parameters

(none)

Return value

(none)

Postconditions

joinable() is false.

Exceptions

std::system_error if an error occurs.

Error conditions

• std::errc if this->get_id() == std::this_thread::get_id() (deadlock detected).
• std::errc if the thread is not valid.
• std::errc if joinable() is false.

Example

#include <chrono>
#include <iostream>
#include <thread>

void foo()
{
    // simulate expensive operation
    std::this_thread::sleep_for(std::chrono::seconds(1));
}

void bar()
{
    // simulate expensive operation
    std::this_thread::sleep_for(std::chrono::seconds(1));
}

int main()
{
    std::cout << "starting first helper...\n";
    std::jthread helper1(foo);

    std::cout << "starting second helper...\n";
    std::jthread helper2(bar);

    std::cout << "waiting for helpers to finish..." << std::endl;
    helper1.join();
    helper2.join();
 
    std::cout << "done!\n";
}

starting first helper...
starting second helper...
waiting for helpers to finish...
done!

References

See also