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# FileHandle.AsyncBytes

An asynchronous sequence of bytes.

```
struct AsyncBytes
```

## Overview

Use the `for`-`await`-`in` syntax to iterate over the bytes in this sequence. For text files, you can also use its <doc://com.apple.documentation/documentation/Swift/AsyncSequence/characters>, <doc://com.apple.documentation/documentation/Swift/AsyncSequence/unicodeScalars>, or <doc://com.apple.documentation/documentation/Swift/AsyncSequence/lines> properties to retrieve the contents in a more convenient format. Since all of these properties conform to <doc://com.apple.documentation/documentation/Swift/AsyncSequence>, as does the [`FileHandle`](/documentation/Foundation/FileHandle) property [`bytes`](/documentation/Foundation/FileHandle/bytes), you can use methods defined by <doc://com.apple.documentation/documentation/Swift/AsyncSequence> to perform powerful inline processing. For example, you can skip the first `n` bytes of the file with `myFileHandle.bytes.prefix(n)`.

## Topics

### Adapting Textual Sequences

[`AsyncCharacterSequence`](/documentation/Foundation/AsyncCharacterSequence)

An asynchronous sequence of characters.

[`AsyncUnicodeScalarSequence`](/documentation/Foundation/AsyncUnicodeScalarSequence)

An asychronous sequence of Unicode scalar values.

[`AsyncLineSequence`](/documentation/Foundation/AsyncLineSequence)

An asynchronous sequence of lines of text.

### Finding Elements

### Selecting Elements

### Excluding Elements

### Transforming a Sequence

### Creating an Iterator

[`makeAsyncIterator()`](/documentation/Foundation/FileHandle/AsyncBytes/makeAsyncIterator())

Creates the asynchronous iterator that produces elements of this asynchronous sequence.

### Supporting Types


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