Mutex

This class is used to create a mutex object that can be used to synchronize access to shared resources.

Interface:

 /**
  * @return bool
  *
  * This function returns the lock status.
  */
 public function isLocked(): bool;

 /**
  * @return Generator
  *
  * This function locks the mutex.
  */
 public function lock(): Generator;

 /**
  * @return Generator
  *
  * This function unlocks the mutex.
  */
 public function unlock(): Generator;