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Mutex

Inherits: RefCounted < Object

A binary Semaphore for synchronization of multiple Threads.

Description

A synchronization mutex (mutual exclusion). This is used to synchronize multiple Threads, and is equivalent to a binary Semaphore. It guarantees that only one thread can ever acquire the lock at a time. A mutex can be used to protect a critical section; however, be careful to avoid deadlocks.

Tutorials

• Using multiple threads

• Thread-safe APIs

Methods

Method Descriptions

void lock ( )

Locks this Mutex, blocks until it is unlocked by the current owner.

Note: This function returns without blocking if the thread already has ownership of the mutex.

bool try_lock ( )

Tries locking this Mutex, but does not block. Returns true on success, false otherwise.

Note: This function returns true if the thread already has ownership of the mutex.

void unlock ( )

Unlocks this Mutex, leaving it to other threads.

Note: If a thread called lock or try_lock multiple times while already having ownership of the mutex, it must also call unlock the same number of times in order to unlock it correctly.