---
title: NSFileProviderPartialContentFetching
framework: fileprovider
role: symbol
role_heading: Protocol
path: fileprovider/nsfileproviderpartialcontentfetching
---

# NSFileProviderPartialContentFetching

Support for fetching part of a file’s content.

## Declaration

```swift
protocol NSFileProviderPartialContentFetching : NSObjectProtocol
```

## Overview

Overview Adopt this protocol to let the system request only part of a file. Apps that read files provided by your extension can benefit from this feature, either by minimizing the amount of data your file provider needs to download, or by finishing the download quickly, freeing up the reading process. important: To trigger a partial download, an app must use POSIX read operations to read part of the file. If you clone the entire file, or read the file using file coordination, the system requests the entire file. For example, a photo app could read just the metadata from each picture in a large album, without having to completely download all the images. Alternatively, a video streaming app could begin playing the video before reading the whole file, reading chunks of data just before it needs them.

## Topics

### Fetching Ranges from a File

- [fetchPartialContents(for:version:request:minimalRange:aligningTo:options:completionHandler:)](fileprovider/nsfileproviderpartialcontentfetching/fetchpartialcontents(for:version:request:minimalrange:aligningto:options:completionhandler:).md)
- [NSFileProviderFetchContentsOptions](fileprovider/nsfileproviderfetchcontentsoptions.md)
- [NSFileProviderMaterializationFlags](fileprovider/nsfileprovidermaterializationflags.md)

## Relationships

### Inherits From

- [NSObjectProtocol](objectivec/nsobjectprotocol.md)

## See Also

### File Provider protocols

- [NSFileProviderReplicatedExtension](fileprovider/nsfileproviderreplicatedextension.md)
- [NSFileProviderEnumerating](fileprovider/nsfileproviderenumerating.md)
- [NSFileProviderIncrementalContentFetching](fileprovider/nsfileproviderincrementalcontentfetching.md)
- [NSFileProviderServicing](fileprovider/nsfileproviderservicing.md)
- [NSFileProviderCustomAction](fileprovider/nsfileprovidercustomaction.md)
- [NSFileProviderExtensionActionIdentifier](fileprovider/nsfileproviderextensionactionidentifier.md)
- [NSFileProviderThumbnailing](fileprovider/nsfileproviderthumbnailing.md)
- [NSFileProviderPendingSetEnumerator](fileprovider/nsfileproviderpendingsetenumerator.md)