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std::mutex::unlock(3)	       C++ Standard Libary	   std::mutex::unlock(3)

NAME
     std::mutex::unlock - std::mutex::unlock

Synopsis
	void unlock();	(since C++11)

	Unlocks the mutex.

	The  mutex must be locked by the current thread of execution, otherwise,
     the behavior
	is undefined.

	This operation synchronizes-with (as defined in  std::memory_order)  any
     subsequent
	lock operation that obtains ownership of the same mutex.

Parameters
	(none)

Return value
	(none)

Exceptions
	Throws nothing.

Notes
	unlock()   is	usually   not	called	directly:  std::unique_lock  and
     std::lock_guard are
	used to manage exclusive locking.

Example
	This example shows how lock and unlock can be  used  to  protect  shared
     data.

     // Run this code

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

      int g_num = 0; // protected by g_num_mutex
      std::mutex g_num_mutex;

      void slow_increment(int id)
      {
	  for (int i = 0; i < 3; ++i)
	  {
	      g_num_mutex.lock();
	      int g_num_running = ++g_num;
	      g_num_mutex.unlock();
	      std::cout << id << " => " << g_num_running << '\n';

	      std::this_thread::sleep_for(std::chrono::seconds(1));
	  }
      }

      int main()
      {
	  std::thread t1(slow_increment, 0);
	  std::thread t2(slow_increment, 1);
	  t1.join();
	  t2.join();
      }

Possible output:
      0 => 1
      1 => 2
      0 => 3
      1 => 4
      0 => 5
      1 => 6

See also
	lock	 locks the mutex, blocks if the mutex is not available
		 (public member function)
	try_lock tries to lock the mutex, returns if the mutex is not available
		 (public member function)
	C documentation for
	mtx_unlock

http://cppreference.com 	   2024.06.10		   std::mutex::unlock(3)
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