std::swap(std::thread) (3) - Linux Manuals

std::swap(std::thread): std::swap(std::thread)

NAME

std::swap(std::thread) - std::swap(std::thread)

Synopsis

void swap( thread &lhs, thread &rhs ) noexcept; (since C++11)

Overloads the std::swap algorithm for std::thread. Exchanges the state of lhs with that of rhs. Effectively calls lhs.swap(rhs).

Parameters

lhs, rhs - threads whose states to swap

Return value

(none)

Example

// Run this code

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

  void foo()
  {
      std::this_thread::sleep_for(std::chrono::seconds(1));
  }

  void bar()
  {
      std::this_thread::sleep_for(std::chrono::seconds(1));
  }

  int main()
  {
      std::thread t1(foo);
      std::thread t2(bar);

      std::cout << "thread 1 id: " << t1.get_id() << std::endl;
      std::cout << "thread 2 id: " << t2.get_id() << std::endl;

      std::swap(t1, t2);

      std::cout << "after std::swap(t1, t2):" << std::endl;
      std::cout << "thread 1 id: " << t1.get_id() << std::endl;
      std::cout << "thread 2 id: " << t2.get_id() << std::endl;

      t1.swap(t2);

      std::cout << "after t1.swap(t2):" << std::endl;
      std::cout << "thread 1 id: " << t1.get_id() << std::endl;
      std::cout << "thread 2 id: " << t2.get_id() << std::endl;

      t1.join();
      t2.join();
  }

Output:

  thread 1 id: 1892
  thread 2 id: 2584
  after std::swap(t1, t2):
  thread 1 id: 2584
  thread 2 id: 1892
  after t1.swap(t2):
  thread 1 id: 1892
  thread 2 id: 2584