std::swap(std::thread)

 

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std::thread

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thread::swap

Non-member functions

swap(std::thread) (C++11)

 

void swap( std::thread& lhs, std::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 <chrono>
#include <iostream>
#include <thread>
 
void foo()
{
    std::this_thread::sleep_for(std::chrono::seconds(1));
}
 
void bar()
{
    std::this_thread::sleep_for(std::chrono::seconds(1));
}
 
int main()
{
    using std::swap;
 
    std::thread t1(foo);
    std::thread t2(bar);
 
    std::cout << "thread 1 id: " << t1.get_id() << '\n'
              << "thread 2 id: " << t2.get_id() << '\n';
 
    swap(t1, t2);
 
    std::cout << "after std::swap(t1, t2):" << '\n'
              << "thread 1 id: " << t1.get_id() << '\n'
              << "thread 2 id: " << t2.get_id() << '\n';
 
    t1.swap(t2);
 
    std::cout << "after t1.swap(t2):" << '\n'
              << "thread 1 id: " << t1.get_id() << '\n'
              << "thread 2 id: " << t2.get_id() << '\n';
 
    t1.join();
    t2.join();
}

Possible 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

See also

swap	swaps two thread objects (public member function)