General: Forums subtopic: App & System Services > Core OS Forums tags: Files and Storage, Foundation, FSKit, File Provider, Finder Sync, Disk Arbitration, APFS Foundation > Files and Data Persistence documentation Low-level file system APIs are documented in UNIX manual pages File System Programming Guide archived documentation About Apple File System documentation Apple File System Guide archived documentation File system changes introduced in iOS 17 forums post On File System Permissions forums post Extended Attributes and Zip Archives forums post Unpacking Apple Archives forums post Creating new file systems: FSKit framework documentation File Provider framework documentation Finder Sync framework documentation App Extension Programming Guide > App Extension Types > Finder Sync archived documentation Managing storage: Disk Arbitration framework documentation Disk Arbitration Programming Guide archived documentation Mass Storage Device Driver Programming Guide archived documentation Device File Access Guide for Storage Devices archived documentation BlockStorageDeviceDriverKit framework documentation Volume format references: Apple File System Reference TN1150 HFS Plus Volume Format Share and Enjoy — Quinn “The Eskimo!” @ Developer Technical Support @ Apple let myEmail = "eskimo" + "1" + "@" + "apple.com"

I have FileProvider based MacOS application, where user is trying to copy the folder having mix of small and large files. Large files are having size ~ 1.5 GB from FileProvider based drive to locally on Desktop. Since the folder was on cloud and not downloaded the copy action triggered the download. Small files were downloaded successfully however during large file download the URLSession timed out. We are using default timeout for URLSession which is 1 min. I tried to capture logs Console.app where i found FileProvider daemon errors. PFA Solutions tried so far: Increased timeout for URLSession from 5 to 10 mins - configuration.timeoutIntervalForRequest Set timeout for resource - configuration.timeoutIntervalForResource It happens when we have low network bandwidth. Network connectivity is there but the bandwidth is low. Any clue by looking at these errors?

I am writing a file provider extension for Finder. I have things working to some extent and I want to add context menu which will 1/ Open an HTTP URL based on the item selected. However, this is not allowed in the code as there is no context for it to open the URL 2/ Documentation (sparse) online talks about the FileProvider UI Extension but that does not seem to be a target 3/ If I use the FinderSyncExtension, it seems it is not fully reliable with the NSReplicatedFileProviderExtenion, as that extension takes precedence and the FinderSyncExtension is not enabled. My question, what is the best way for the FileProviderExtension to do some UI work? like open a URL, show alert messages etc?

We have applications RME and RMEUI, which are added under FileProviders section. Looking for MDM profile that can lock these entries so that users cannot disable them. Currently we are using JAMF Pro MDM to control our applications. In Sequoia OS -> Open System Preferences -> General -> Login Items & Extensions -> Under Extensions section -> File Providers In Tahoe OS -> Open System Preferences -> General -> Login Items & Extensions -> Under By Category/App section -> File Providers (In the screen shot you can find RME entry)

I'm unable to API such as NSFileProviderManager on MacOS catalyst although the developer site says this extension is supported. https://developer.apple.com/documentation/fileprovider I've attempted to build a iOS framework to import into the catalyst target with no luck (I thought Catalyst was against the iOS API — maybe not?). Also attempted building a MacOS framework to import (maybe it's the other way around) but no luck. Has anyone found a workaround? Building for "MacOS for iPad" does work but isn't ideal for the UI.

I am in the process of writing a macOS app using NSFileProviderExtension so that I can map my customer's data in Finder. I am in the process of building it out, I had initially started in Obj-C and then after the advice of folks here (https://developer.apple.com/forums//thread/793272?answerId=849339022&page=1#849752022) I have switched to Swift as the NSReplicatedFileProvider is not available in Obj-C. I have done the main app and also started plugging away with the FileProviderExtension. To verify that I have properly setup, I create a static list of files in the FileProviderExtension enumerate so I can see it work in Finder. I build the app and it works as expected and I see it mounted in Finder and I see the static list of files. But what I don't see is any debug statements in the app, none of those message show up in the logs. I am baffled by this. I check the log stream to see what the process prints out and I know it is logging everything else eg: 2025-07-18 11:32:05.772364-0700 0x19ea3f9 Activity 0x1172100 63622 0 DriveFileProviderExtension: (libsystem_secinit.dylib) AppSandbox 2025-07-18 11:32:05.794609-0700 0x19ea3f9 Activity 0x1172101 63622 0 DriveFileProviderExtension: (libsystem_info.dylib) Retrieve User by ID 2025-07-18 11:32:05.800179-0700 0x19ea3f9 Default 0x0 63622 0 DriveFileProviderExtension: (ExtensionFoundation) [com.apple.extensionkit:default] Extension `/Users/radwar/Library/Developer/Xcode/DerivedData/Drive-fxfhbjutfvumoabnnfmxxstpifha/Build/Products/Debug/Drive.app/Contents/PlugIns/DriveFileProviderExtension.appex/Contents/MacOS/DriveFileProviderExtension` of type: `1` launched. 2025-07-18 11:32:05.801453-0700 0x19ea3f9 Default 0x0 63622 0 DriveFileProviderExtension: (RunningBoardServices) [com.apple.runningboard:connection] Initializing connection 2025-07-18 11:32:05.803083-0700 0x19ea3f9 Default 0x0 63622 0 DriveFileProviderExtension: (RunningBoardServices) [com.apple.runningboard:process] Removing all cached process handles 2025-07-18 11:32:05.803231-0700 0x19ea613 Default 0x0 63622 0 DriveFileProviderExtension: (RunningBoardServices) [com.apple.runningboard:connection] Sending handshake request attempt #1 to server 2025-07-18 11:32:05.803414-0700 0x19ea613 Default 0x0 63622 0 DriveFileProviderExtension: (RunningBoardServices) [com.apple.runningboard:connection] Creating connection to com.apple.runningboard 2025-07-18 11:32:05.803459-0700 0x19ea613 Default 0x0 63622 0 DriveFileProviderExtension: (libxpc.dylib) [com.apple.xpc:connection] [0x12f106e10] activating connection: mach=true listener=false peer=false name=com.apple.runningboard 2025-07-18 11:32:05.805893-0700 0x19ea613 Default 0x0 63622 0 DriveFileProviderExtension: (RunningBoardServices) [com.apple.runningboard:connection] Handshake succeeded 2025-07-18 11:32:05.805955-0700 0x19ea613 Default 0x0 63622 0 DriveFileProviderExtension: (RunningBoardServices) [com.apple.runningboard:connection] Identity resolved as xpcservice<clio.Drive.DriveFileProviderExtension([osservice<com.apple.FileProvider(501)>:990])(501)>{vt hash: 247410607}[uuid:454E32DB-3FB4-4DC6-9C05-F4B2F97333E0]{persona:9EF54117-4998-4D72-83C4-F12587C95FBA} but none of my print lines are being printed. I have code like this sprinkled through the methods: print("🔍 FileProviderExtension INIT - Logger configured") print("🔍 Domain: \(domain.displayName)") None of these show up anywhere. I also do a pure log stream with all system output, and there, too, I don't see anything. What am I missing? With my Obj-C version, all NSLogs used to show up as expected. With Swift, am I missing something?

Currently, I use NSFileProviderItemCapabilitiesAllowsAddingSubitems on a folder to control the creation of sub-items (either folders or files) within a parent folder. However, this capability doesn't allow me to meet a requirement where I need to permit file creation but restrict folder creation. I am seeking input on different options to achieve this requirement. Note: One reactive approach would be to intercept folder creation within the createItem() event handler and reject it with an ExcludedFromSync error (without uploading to cloud). This would prevent createItem() from being reattempted on that folder, but the folder would still remain on the mount. Is there any way to delete it?

Hi there, I am in the process of writing a macOS app using NSFileProviderExtension so that I can map my customer's data in Finder. I am in the process of building it out. But one thing I notice is that once the file is downloaded and I save it to the cache folder, I see it disappear from the folder. It looks like the system removed the downloaded file a few seconds later. How do I go about tracking this? I have added the log stream messages from the point where it is downloaded to the point where it is gone missing. Any pointers greatly appreciated. 2025-07-15 16:10:41.989915-0700 0x138326 Default 0x0 989 0 filecoordinationd: (Foundation) [com.apple.foundation.filecoordination:provider] Provider radwar.Drive.DriveFileProviderExtension finished providing for 44FB3A4A-CA50-4EE2-9DC8-1C96FE584DF5 2025-07-15 16:10:41.989974-0700 0x138326 Default 0x0 989 0 filecoordinationd: (Foundation) [com.apple.foundation.filecoordination:claims] Provider radwar.Drive.DriveFileProviderExtension finished, unblocking claimer for 44FB3A4A-CA50-4EE2-9DC8-1C96FE584DF5 2025-07-15 16:10:41.987613-0700 0x138bb6 Default 0x0 990 0 fileproviderd: (Foundation) [com.apple.foundation.filecoordination:provider] radwar.Drive.DriveFileProviderExtension finished providing 2025-07-15 16:10:42.034144-0700 0x138905 Default 0x71f4b8 624 7 runningboardd: (RunningBoard) [com.apple.runningboard:ttl] Invalidating assertion 624-44341-46806 (target:[xpcservice<radwar.Drive.DriveFileProviderExtension([osservice<com.apple.FileProvider(501)>:990])(501)>{vt hash: 247410607}[uuid:5AABEA5E-ACAD-428B-A6DD-F2EFF14CEE99]{persona:9EF54117-4998-4D72-83C4-F12587C95FBA}:44341]) from originator [xpcservice<radwar.Drive.DriveFileProviderExtension([osservice<com.apple.FileProvider(501)>:990])(501)>{vt hash: 247410607}[uuid:5AABEA5E-ACAD-428B-A6DD-F2EFF14CEE99]{persona:9EF54117-4998-4D72-83C4-F12587C95FBA}:44341] 2025-07-15 16:10:44.185866-0700 0x138906 Default 0x0 624 7 runningboardd: (RunningBoard) [com.apple.runningboard:ttl] [xpcservice<radwar.Drive.DriveFileProviderExtension([osservice<com.apple.FileProvider(501)>:990])(501)>{vt hash: 247410607}[uuid:B08DACEF-EDCC-4DE9-91AA-DC26EDB2FA89]{persona:9EF54117-4998-4D72-83C4-F12587C95FBA}:44328] termination reported by launchd (0, 0, 0) 2025-07-15 16:10:44.186166-0700 0x138906 Default 0x0 624 0 runningboardd: (RunningBoard) [com.apple.runningboard:process] Removing process: [xpcservice<radwar.Drive.DriveFileProviderExtension([osservice<com.apple.FileProvider(501)>:990])(501)>{vt hash: 247410607}[uuid:B08DACEF-EDCC-4DE9-91AA-DC26EDB2FA89]{persona:9EF54117-4998-4D72-83C4-F12587C95FBA}:44328] 2025-07-15 16:10:44.186424-0700 0x138906 Default 0x0 624 0 runningboardd: (RunningBoard) [com.apple.runningboard:process] Removing assertions for terminated process: [xpcservice<radwar.Drive.DriveFileProviderExtension([osservice<com.apple.FileProvider(501)>:990])(501)>{vt hash: 247410607}[uuid:B08DACEF-EDCC-4DE9-91AA-DC26EDB2FA89]{persona:9EF54117-4998-4D72-83C4-F12587C95FBA}:44328] 2025-07-15 16:10:44.189939-0700 0x138c30 Default 0x71f4e4 976 0 gamepolicyd: (RunningBoardServices) [com.apple.runningboard:monitor] Received state update for 44328 (xpcservice<radwar.Drive.DriveFileProviderExtension([osservice<com.apple.FileProvider(501)>:990])(501)>{vt hash: 247410607}[uuid:B08DACEF-EDCC-4DE9-91AA-DC26EDB2FA89]{persona:9EF54117-4998-4D72-83C4-F12587C95FBA}, none-NotVisible 2025-07-15 16:10:44.190503-0700 0x138c8f Default 0x0 624 0 runningboardd: (RunningBoard) [com.apple.runningboard:process] XPC connection invalidated: [xpcservice<radwar.Drive.DriveFileProviderExtension([osservice<com.apple.FileProvider(501)>:990])(501)>{vt hash: 247410607}[uuid:B08DACEF-EDCC-4DE9-91AA-DC26EDB2FA89]{persona:9EF54117-4998-4D72-83C4-F12587C95FBA}:44328] 2025-07-15 16:10:46.294619-0700 0x13904a Default 0x0 44341 0 DriveFileProviderExtension: 🔥FileProviderExtension: 🔥FileProviderExtension: ❌ CRITICAL: File disappeared after 5 seconds! /Users/radwar/Library/Containers/radwar.Drive.DriveFileProviderExtension/Data/Library/Caches/FileCache/README.md (item: 19105790787)```

We have a seemingly randomly (and rarely) reproducible bug when a Microsoft Word (or Excel, Powerpoint...) temporary file with the ~$ prefix is not removed when the document is closed and causes a remotely deleted folder to be recreated via our file provider extension. We have received multiple issues from our users for some time now, and we could not reproduce it so far, but finally got a repro but could not identify the cause. We could reproduce it with the following steps, however not always, and only on one computer: We have the following file: FileProviderRoot/TEST/INSIDE/somefile.docx Open this file, edit with MS Word. A ~$mefile.docx hidden, temporary file is created next to the original file, while it is open in Word. This temp file is ignored by our file provider implementation by returning an .excludeFromSync error code. Save the file, modifications are synced. (don't know if this step is needed) We delete the container folder (FileProviderRoot/TEST/INSIDE) from within our app, the deletion change is propagated to the file provider, which in turn receives a call to createItem(basedOn:fields:contents:options:request:completionHandler:) that recreates the INSIDE folder, as - for some reason - the temp file cannot be deleted. Now we are stuck in this loop of delete/recreate until we go into the file provider folder and manually remove the stuck temp file. We would expect that the folder is not recreated but also removed from the file provider and disk along with the temp file. On the device that this issue was reproduced, it also seems to work correctly most of the time, but needs manual fixing when this issue occurs. We have a related bugreport: FB17928069

I am developing a FileProvider on Mac OS. I want to support Coauthoring Via Microsoft. As per Microsoft's documentation, the supportedServices function should be called via the OS when an Office file is opened. I have overridden this function in my fileprovider extension, but fail to see this function getting called. Has anyone else had any experience with coauthoring integration for File Provider and could give some advice? I am mostly working from the given documentation from Microsoft https://learn.microsoft.com/en-us/microsoft-365/cloud-storage-partner-program/plus/sync-client/metadata

Hi We have a non-replicated Files Provider extension on iOS that creates multiple domains. I've noticed that iOS typically creates one process per domain, so I would assume that each process is meant to handle one domain. However, in practice, is seems that calls for any domain can occur in any process. I'm wondering whether there is supposed to be a mapping, implying there might be something wrong with the code, or whether we shouldn't make assumptions about domain:process mapping. Thanks for any info you can provide.

In the FileProvider framework, most of the functions (such as fetchPartialContentsForItemWithIdentifier, fetchContentsForItemWithIdentifier etc.) are expected to return an NSProgress object. In a case where an error is encountered before the function returns the NSProgress object, is it allowed to invoke the completionHandler with an error prior to returning the NSProgress object to the File Provider framework?

I'm not sure if I have found a bug with iOS or if it's just unexpected behavior with my implementation. I have a gomobile library that sets up a local http server. It needs to be able to write to temporary storage. If I use the shared library from my main apps process it can write to the file manager.default temporary storage. while Xcode is running a debug session I can use that same process from my file provider replicated extension and it works fine. However I realized running my file provider extension where it starts the gomobile shared library directly instead of first from my app the library fails to write anything to the file provider manager default temporary storage or the file provider manager for my file provider domain temporary storage or even the app group library. it is odd, because I have a swift URL extension that confirms the temporary storage can be written to from swift. I have monitored console logs for fileproviderd, my file extension and have tried writing data to a log file. nothing seems to catch exactly what causes the file provider extension to crash and restart. I also cannot keep the shared gomobile server running in the background on iOS even if I were to force the user to "authenticate" with the main app first. Im pretty sure the file provider extension needs to run the gomobile library for it to work right. I'm wondering if something may be wrong with the iOS sandbox that could be preventing the file provider extension to let a c based gomobile shared library from accessing the temporary storage. Any guidance for further things to try would be greatly appreciated. I have tried every avenue I can think of. I cannot run just the appex itself on either my m4 pro MacBook or my iPhone so attaching the debugger has been tricky and I don't see much in the way of useful logs in console app either just a swarm of noise. Im fairly confident it's an issue to writing to temporary storage from the gomobile c library and not much else. App was working great on macOS designed for iPad which just seemed rather ironic that an iOS code base runs better on macOS than it was able to on my iPhone 16 pro max. Like im all for the sandbox I just wish it didn't treat c level gomobile libraries different than it treats the swift code itself.

We are experimenting with FileProvider on MacOS, we want to set ACL policy restriction on a folder and the same policy needs to be applied down to its children. To achieve this currently we are setting corresponding NSFileProviderItemCapabilities on parent folder and recursively iterate over all of its children and set the capability on each individual child items. GOAL: We expect the root's ACL policy to be implicitly percolated down to its children without explicitly being iterated over them and setting it individually. From our research, we couldn't find any policy that can help us achieve the above goal. If there are any such provisions in FileProvider, please guide us to them.

I tried using Pluginkit via terminal to determine if a File Provider Extension is enabled on Mac OS. Although I see the extension listed in the output of pluginkit -m, The status of + or - doesn't seem to change in this output when I disable or enable the FileProvider extension in System Settings. Is there a more reliable way to determine if the extension is enabled ?

Hi all, I’m building an iOS app where I need to determine user picked files or folders using UIDocumentPickerViewController, whether the selected item is synced or managed by a cloud storage provider such as: Google Drive iCloud Drive OneDrive Dropbox or any third-party File Provider extension My intent is to detect this and optionally warn the user that the item may be subject to syncing behavior. So far, I’ve tried a few different approaches: Extended Attributes (listxattr / getxattr) While this does not give reliable outcome. Heuristically search for keywords like 'Drive', 'GoogleDrive' etc But this is also not reliable. Question Is there any possible reliable and documented way to detect programmatically if a file/folder is cloud-synced or managed by a File Provider from within a regular iOS app (not an extension), especially for: Google Drive OneDrive Dropbox iCloud Other third-party providers? Also, is there any recommended fallback strategy for iOS versions prior to 17 where NSFileProviderManager may have limitations? Any input from Apple engineers or those who have tackled this would be hugely appreciated! Thanks in advance 🙌

Hi Is there a way to check if a file at a specified URL is open and being edited by another application. Assuming that we have permission to access the file at the URL.

I want to implement quota feature to my file provider extension. I am able to keep track of materialized files total size. (Content download and edit operations) However I cannot detect file eviction operation (User right click to file and select "Remove Download"). Is there anyway to detect this action Or any suggestion to keep track of materialized files total size?

I support a pair of iOS apps that use a file provider extension. One app exposes a file provider extension, including a file provider extension service and the other app interacts with the file provider extension and uses the service. On iOS 18.3 and before, this all works fine. On iOS 18.4, getFileProviderServicesForItem fails when called from the consuming app with: Error Domain=NSCocoaErrorDomain Code=513 "The file couldn’t be saved because you don’t have permission." The supportedServiceSources method in the service hosted by the provider app is never invoked when this occurs. Is there some change to the mechanism for iOS 18.4 that I've not found yet?

I was able to add new domain with 'NSFileProviderManager.add' function in Xcode past 2 months. Yesterday I created .pkg file (installer file) for distribution with 'pkgbuild' and 'productbuild' commands in terminal. I successfully install application and test it then uninstall it. However after this, In Xcode I cannot add new domain anymore. I keep getting "Error Domain=NSFileProviderErrorDomain Code=-2001 "No valid file provider found with identifier ‘’." Command that used to create .pkg file pkgbuild --root "path" --scripts "path" --identifier "same bundle identifier with app" --version 1.0 --install-location /Applications "newpkg.pkg" productbuild --synthesize --package "newpkg.pkg" Distribution.xml productbuild --distribution Distribution.xml --package-path "newpath.pkg" "newpathrelease.pkg" NOTE: When app is installed (But not running). I am able to add new domain in Xcode. After I uninstall app, I start to get same error again NOTE: I uninstall app by move it to Trash from Applications directory in finder Any suggestion about add new domain in Xcode during development? Or How to fix 'No valid file provider found with identifier' error

Hi all, i am trying to implement File Provider Extension. I have some questions about conflict resolution Same file is changed at user local and remote storage before it's synced. File has 2 different version at user local and remote storage. After trigger a new enumeration by calling signalEnumerator for the extension, I want to move user's local version to new conflicted copy (with new itemIdentifier: NSFileProviderItemIdentifier) and import remote storage version to user local (with current itemIdentifier: NSFileProviderItemIdentifier). Then users local version should uploaded to remote storage server with new conflicted copy name Any suggestion about this scenario? Or any documentation about conflict resolution