FPE

File Provider Extension

An extension other apps use to access files and folders managed by your app and synced with a remote storage.


The framework has two different starting points for building your File Provider extension.

NSFileProviderReplicatedExtension

The system manages the content accessed through the File Provider extension. Available in macOS 11+ and iOS 16+.

NSFileProviderExtension

The extension hosts and manages the files accessed through the File Provider extension. Available in iOS 11+.

The replicated extension takes responsibility for monitoring and managing the local copies of your documents. The file provider focuses on syncing data between the local copy and the remote storage—uploading any local changes and downloading any remote changes. For more information, see Replicated File Provider extension.

The nonreplicated extension manages a local copy of the extension’s content, including creating and managing placeholders for remote files. It also syncs the content with your remote storage. For more information, see Nonreplicated File Provider extension.



FUSE

Filesystem in Userspace (FUSE) is a software interface for Unixand Unix-like computer operating systems that lets non-privileged users create their own file systems without editing kernel code. This is achieved by running file system code in user space while the FUSE module provides only a bridge to the actual kernel interfaces.

FUSE is available for Linux, FreeBSD, OpenBSD, NetBSD (as puffs), OpenSolaris, Minix 3, macOS, and Windows.

USB-A

Unlike other data buses (such as Ethernet), USB connections are directed; a host device has "downstream" facing ports that connect to the "upstream" facing ports of devices. Only downstream facing ports provide power; this topology was chosen to easily prevent electrical overloads and damaged equipment. Thus, USB cables have different ends: A and B, with different physical connectors for each. Each format has a plug and receptacle defined for each of the A and B ends. A USB cable, by definition, has a plug on each end—one A (or C) and one B (or C)—and the corresponding receptacle is usually on a computer or electronic device. The mini and micro formats may connect to an AB receptacle, which accepts either an A or a B plug, that plug determining the behavior of the receptacle.

artifact

A compression artifact (or artefact) is a noticeable distortion of media (including images, audio, and video) caused by the application of lossy compression. Lossy data compression involves discarding some of the media's data so that it becomes small enough to be stored within the desired disk space or transmitted (streamed) within the available bandwidth(known as the data rate or bit rate). If the compressor cannot store enough data in the compressed version, the result is a loss of quality, or introduction of artifacts. The compression algorithm may not be intelligent enough to discriminate between distortions of little subjective importance and those objectionable to the user.