swap(std::jthread)

 

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std::jthread

Member functions

jthread::jthread

jthread::~jthread

jthread::operator=

Observers

jthread::joinable

jthread::get_id

jthread::native_handle

jthread::hardware_concurrency

Operations

jthread::join

jthread::detach

jthread::swap

Stop token handling

jthread::get_stop_source

jthread::get_stop_token

jthread::request_stop

Non-member functions

swap(std::jthread)

 

friend void swap( jthread& lhs, jthread& rhs ) noexcept;		(since C++20)

Overloads the std::swap algorithm for std::jthread. Exchanges the state of lhs with that of rhs. Effectively calls lhs.swap(rhs). This function is not visible to ordinary unqualified or qualified lookup, and can only be found by argument-dependent lookup when std::jthread is an associated class of the arguments.

Parameters

lhs, rhs

-

jthreads 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::jthread t1(foo);
    std::jthread 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';
 
 
}

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 jthread objects (public member function)