# init(value:) Creates new counting semaphore with an initial value. ``` init(value: Int) ``` ## Parameters `value` The starting value for the semaphore. Do not pass a value less than zero. ## Return Value The newly created semaphore. ## Discussion Passing zero for the value is useful for when two threads need to reconcile the completion of a particular event. Passing a value greater than zero is useful for managing a finite pool of resources, where the pool size is equal to the value. > Important: > Calls to ``doc://com.apple.dispatch/documentation/Dispatch/DispatchSemaphore/signal()`` must be balanced with calls to ``doc://com.apple.dispatch/documentation/Dispatch/DispatchSemaphore/wait()``. Attempting to dispose of a semaphore with a count lower than `value` causes an `EXC_BAD_INSTRUCTION` exception. --- 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)