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NSLocking Protocol Reference

Overview

The NSLocking protocol declares the elementary methods adopted by classes that define lock objects. A lock object is used to coordinate the actions of multiple threads of execution within a single application. By using a lock object, an application can protect critical sections of code from being executed simultaneously by separate threads, thus protecting shared data and other shared resources from corruption.

Tasks

Working with Locks

• – lock
• – unlock

Instance Methods

lock

Attempts to acquire a lock, blocking a thread’s execution until the lock can be acquired.

- (void)lock

Discussion

An application protects a critical section of code by requiring a thread to acquire a lock before executing the code. Once the critical section is past, the thread relinquishes the lock by invoking unlock.

Availability

• Available in Mac OS X v10.0 and later.

Related Sample Code

• SimpleThreads

Declared In

NSLock.h

unlock

Relinquishes a previously acquired lock.

- (void)unlock

Availability

• Available in Mac OS X v10.0 and later.

Related Sample Code

• SimpleThreads

Declared In

NSLock.h

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