# NSDistributedLock A lock that multiple applications on multiple hosts can use to restrict access to some shared resource, such as a file. ``` class NSDistributedLock ``` ## Overview The lock is implemented by an entry (such as a file or directory) in the file system. For multiple applications to use an [`NSDistributedLock`](/documentation/Foundation/NSDistributedLock) object to coordinate their activities, the lock must be writable on a file system accessible to all hosts on which the applications might be running. Use the [`try()`](/documentation/Foundation/NSDistributedLock/try()) method to attempt to acquire a lock. You should generally use the [`unlock()`](/documentation/Foundation/NSDistributedLock/unlock()) method to release the lock rather than [`break()`](/documentation/Foundation/NSDistributedLock/break()). [`NSDistributedLock`](/documentation/Foundation/NSDistributedLock) doesn’t conform to the [`NSLocking`](/documentation/Foundation/NSLocking) protocol, nor does it have a `lock` method. The protocol’s [`lock()`](/documentation/Foundation/NSLocking/lock()) method is intended to block the execution of the thread until successful. For an [`NSDistributedLock`](/documentation/Foundation/NSDistributedLock) object, this could mean polling the file system at some predetermined rate. A better solution is to provide the [`try()`](/documentation/Foundation/NSDistributedLock/try()) method and let you determine the polling frequency that makes sense for your application. ## Topics ### Creating an NSDistributedLock [`lockWithPath:`](/documentation/Foundation/NSDistributedLock/lockWithPath:) Returns an `NSDistributedLock` object initialized to use as the locking object the file-system entry specified by a given path. [`init(path:)`](/documentation/Foundation/NSDistributedLock/init(path:)) Initializes an `NSDistributedLock` object to use as the lock the file-system entry specified by a given path. ### Acquiring a Lock [`try()`](/documentation/Foundation/NSDistributedLock/try()) Attempts to acquire the receiver and immediately returns a Boolean value that indicates whether the attempt was successful. ### Relinquishing a Lock [`break()`](/documentation/Foundation/NSDistributedLock/break()) Forces the lock to be relinquished. [`unlock()`](/documentation/Foundation/NSDistributedLock/unlock()) Relinquishes the receiver. ### Getting Lock Information [`lockDate`](/documentation/Foundation/NSDistributedLock/lockDate) Returns the time the receiver was acquired by any of the `NSDistributedLock` objects using the same path. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)