# withDecompressionStream(readingFrom:flags:threadCount:_:) Calls the given closure with a decompression sequential input stream. ``` static func withDecompressionStream(readingFrom compressedStream: ArchiveByteStream, flags: ArchiveFlags = [], threadCount: Int = 0, _ body: (ArchiveByteStream) throws -> E) throws -> E ``` ## Parameters `compressedStream` An input stream that provides compressed data, the operation only calls [`read(into:)`](/documentation/AppleArchive/ArchiveByteStreamProtocol/read(into:)) and [`read(into:atOffset:)`](/documentation/AppleArchive/ArchiveByteStreamProtocol/read(into:atOffset:)). `flags` Flags that control the behavior of the operation. `threadCount` The number of worker threads that the operation uses, set to `0` for default. `body` A closure with the archive byte stream passed as a parameter. ## Return Value The result of the closure. ## Discussion This function opens a stream created by [`decompressionStream(readingFrom:flags:threadCount:)`](/documentation/AppleArchive/ArchiveByteStream/decompressionStream(readingFrom:flags:threadCount:)), calls the specified closure, and closes the stream. --- 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)