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# lock(before:)

Attempts to acquire a lock before a given date.

```
func lock(before limit: Date) -> Bool
```

## Parameters

`limit`

The time before which the lock should be acquired.

## Return Value

<doc://com.apple.documentation/documentation/Swift/true> if the lock is acquired before `limit`, otherwise <doc://com.apple.documentation/documentation/Swift/false>.

## Discussion

The thread is blocked until the receiver acquires the lock or `limit` is reached.

## See Also

  [Threading Programming Guide](https://developer.apple.com/library/archive/documentation/Cocoa/Conceptual/Multithreading/Introduction/Introduction.html#//apple_ref/doc/uid/10000057i)


---

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