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std::unique_lock<Mutex>:: swap

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std::unique_lock
void swap ( unique_lock & other ) noexcept ;
(since C++11)

Exchanges the internal states of the lock objects.

Contents

Parameters

other - the lock to swap the state with

Return value

(none)

Example

Run this code 
#include <iostream>
#include <mutex>
int main()
{
    std::mutex mtx1;
    std::unique_lock<std::mutex> guard1(mtx1);
    std::unique_lock<std::mutex> guard2;
    guard2.swap(guard1);
    if (!guard1 && guard2)
        std::cout << "swapped success\n";
    return 0;
}

Output: 

swapped success

See also

(C++11)
specializes the std::swap algorithm
(function template)