Mutex and lock are synchronization mechanisms used in concurrent programming to control access to shared resources by multiple threads or processes. Although they serve a similar purpose, there are some differences between them:
Scope:
Mutex (Mutual Exclusion): Typically, mutexes are system-wide or global in scope, meaning they can be used to synchronize threads or processes across the entire system.
Lock: Locks are often used within a single process or application to synchronize threads.
Usage:
Mutex: Mutexes are often used to provide exclusive access to shared resources. A thread that wants to access a shared resource locks the mutex, performs its operation, and then unlocks the mutex.
Lock: Locks are a more general term and can refer to various synchronization primitives, including mutexes, semaphores, and spinlocks.
Implementation:
Mutex: Mutexes are typically implemented using hardware primitives like atomic operations or software constructs like semaphores. They ensure that only one thread can acquire the lock at a time.
Lock: Locks can encompass a broader range of synchronization mechanisms. They can be implemented using mutexes, spinlocks, semaphores, or other techniques, depending on the requirements and characteristics of the system.
Flexibility:
Mutex: Mutexes often provide a simple binary state - locked or unlocked. They are well-suited for scenarios where exclusive access to a resource is required.
Lock: Locks can be more flexible, allowing for different modes of operation such as shared locks (multiple threads can read but not write) and exclusive locks (only one thread can write).