I've gotten to the point where I can use the mount(8) command line tool and the -t option to mount a file system using my FSKit file system extension, in which case I can see a process for my extension launch, probe, and perform the other necessary actions.
However, when plugging in my USB flash drive or trying to mount with diskutil mount, the file system does not mount:
$ diskutil mount disk20s3
Volume on disk20s3 failed to mount
If you think the volume is supported but damaged, try the "readOnly" option
$ diskutil mount readOnly disk20s3
Volume on disk20s3 failed to mount
If you think the volume is supported but damaged, try the "readOnly" option
Initially I thought it would be enough to just implement probeExtension(resource:replyHandler:) and the system would handle the rest, but this doesn't seem to be the case. Even a trivial implementation that always returns .usable doesn't cause the system to use my FSModule, even though I've enabled my extension in System Settings > General > Login Items & Extensions > File System Extensions.
From looking at some of the open source msdos and Disk Arb code, it seems like my app extension needs to list FSMediaTypes to probe. I eventually tried putting this in my Info.plist of the app extension:
<key>FSMediaTypes</key>
<dict>
<key>EBD0A0A2-B9E5-4433-87C0-68B6B72699C7</key>
<dict>
<key>FSMediaProperties</key>
<dict>
<key>Content Hint</key>
<string>EBD0A0A2-B9E5-4433-87C0-68B6B72699C7</string>
<key>Leaf</key>
<true/>
</dict>
</dict>
<key>0FC63DAF-8483-4772-8E79-3D69D8477DE4</key>
<dict>
<key>FSMediaProperties</key>
<dict>
<key>Content Hint</key>
<string>0FC63DAF-8483-4772-8E79-3D69D8477DE4</string>
<key>Leaf</key>
<true/>
</dict>
</dict>
<key>Whole</key>
<dict>
<key>FSMediaProperties</key>
<dict>
<key>Leaf</key>
<true/>
<key>Whole</key>
<true/>
</dict>
</dict>
<key>ext4</key>
<dict>
<key>FSMediaProperties</key>
<dict>
<key>Content Hint</key>
<string>ext4</string>
<key>Leaf</key>
<true/>
</dict>
</dict>
</dict>
</plist>
(For reference, the partition represented by disk20s3 has a Content Hint of 0FC63DAF-8483-4772-8E79-3D69D8477DE4 and Leaf is True which I verified using IORegistryExplorer.app from the Xcode additional tools.)
Looking in Console it does appear now that the system is trying to use my module (ExtendFS_fskit) to probe when I plug in my USB drive, but I never see a process for my extension actually launch when trying to attach to it from Xcode by name (unlike when I use mount(8), where I can do this). However I do see a Can't find the extension for <private> error which I'm not sure is related but does sound like the system can't find the extension for some reason.
The below messages are when filtering for "FSKit":
default 19:14:53.455826-0400 diskarbitrationd probed disk, id = /dev/disk20s3, with ExtendFS_fskit, ongoing.
default 19:14:53.456038-0400 fskitd Incomming connection, entitled 1
default 19:14:53.456064-0400 fskitd [0x7d4172e40] activating connection: mach=false listener=false peer=true name=com.apple.filesystems.fskitd.peer[350].0x7d4172e40
default 19:14:53.456123-0400 fskitd Hello FSClient! entitlement yes
default 19:14:53.455902-0400 diskarbitrationd [0x7461d8dc0] activating connection: mach=true listener=false peer=false name=com.apple.filesystems.fskitd
default 19:14:53.456151-0400 diskarbitrationd Setting remote protocol to all XPC
default 19:14:53.456398-0400 fskitd About to get current agent for 501
default 19:14:53.457185-0400 diskarbitrationd probed disk, id = /dev/disk20s3, with ExtendFS_fskit, failure.
error 19:14:53.456963-0400 fskitd -[fskitdXPCServer applyResource:targetBundle:instanceID:initiatorAuditToken:authorizingAuditToken:isProbe:usingBlock:]: Can't find the extension for <private>
(I only see these messages after plugging my USB drive in. When running diskutil mount, I see no messages in the console when filtering by FSKit, diskarbitrationd, or ExtendFS afterward. It just fails.)
Is there a step I'm missing to get this to work, or would this be an FSKit bug/current limitation?
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My app is a VoIP softphone for Mac that allows people to make phone calls to a regular phone numbers. The app exists since before Mac App Store. The app declares itself to the system as capable of handling tel: URLs. Until now, people could change the default handler for tel URLs in FaceTime settings (Default for calls).
In macOS Tahoe 26, this doesn't seem to be possible any more. That option is gone from the FaceTime settings.
Is it completely gone or has it been moved somewhere else? If there is no UI control for this any more, is it possible to change it programmatically?
Hi all, I have set up a trivial test project to try Apple-hosted background assets following the instructions in the three articles at https://developer.apple.com/documentation/backgroundassets.
When I run the local mock server with xcrun ba-serve and set the URL override in Settings as described in the "Testing asset packs locally" article, I am able to download a test pack on my iOS devices. On the Mac that I use to run the mock server, however, the same call to AssetPackManager.shared.assetPack(withID: "TestAssetPack") that works on iOS always reports
The asset pack with the ID “TestAssetPack” couldn’t be looked up: No asset pack with the ID “TestAssetPack” was found.
even when not running the mock server, which led me to believe that it may not be hitting it at all. In fact, the macOS app will download asset packs uploaded to App Store Connect even when running the local server and setting the xcrun ba-serve url-override to the exact same string as in Settings on iOS. My initial suspicion was that something is wrong with the URL override, so I have tried all combinations of the Mac's hostname, IP address or "localhost" (with the corresponding SSL certificates) with and without port 443, always prefixing with "https://" for the url-override. All the same.
Does anyone have an idea what may be the issue here?
My asset pack has the following manifest:
{
"assetPackID": "TestAssetPack",
"downloadPolicy": {
"onDemand": {}
},
"fileSelectors": [
{
"file": "TestAsset.txt"
}
],
"platforms": [
"iOS",
"macOS"
]
}
I am running v26.1 for macOS, iOS & Xcode.
Edit:
Just to be clear, my assumption here is that the URL overrides (in Settings on iOS or via ba-serve on macOS) is what should cause the app to hit the mock server. Is that correct or am I missing something?
macos 15.4 beta claims to support FSKit. Is there an FSKit sample available?
I don't see anything useful in the published docs.
Hello team,
I am trying to find out a way to block urls in the chrome browser if it is found in local blocked list cache. I found URL Filter Network very much suitable for my requirement. But I see at multiple places that this solution is only for Enterprise level or MDM or supervised device. So can I run this for normal user ? as my targeting audience would be bank users. One more thing how can I test this in development environment if we need supervised devices and do we need special entitlement ?
When trying to run sample project in the simulator then getting below error
Background:
We are developing a cross-platform mobile application that communicates with a custom NFC-enabled hardware device. The hardware expects ISO7816-style APDU commands for data exchange and functions correctly with Android using the IsoDep protocol.
Observed Issue on iOS:
On iOS, the tag is only detectable via NFCNdefReaderSession, which provides access to INFCNdefTag.
Attempting to use NFCTagReaderSession with NFCPollingOption.Iso14443 (which is required for APDU communication) results in no tag detection.
As a result, the tag is inaccessible for APDU-based communication on iOS.
Since NFCNdefReaderSession does not support APDU, we are unable to establish the required command channel.
Constraints:
The hardware firmware cannot be changed to support NDEF-based command interpretation.
The device expects raw ISO-DEP APDU commands (i.e., Class-Instruction-Param1-Param2-Data-Le).
Impact:
The lack of ISO7816 tag detection on iOS prevents the app from sending APDU commands, resulting in a platform-specific feature limitation.
Functionality that relies on secure, structured APDU communication is unavailable to iOS users, even though it works seamlessly on Android.
We have a that relies on accurate GPS location but we’ve noticed that every now and then the location ‘jumps’ a few hundred meters to a different location but reports horizonal accuracy less than 10m.
we think the device is picking up a rough location from a local WiFi rather than internal gps sensors.
can we
a) disable WiFi location Updates?
b) identify WiFi location Updates?
thank You
I'm unable to view Changes or Diff View in the Deploy Schema Changes Dialog due to an Internal Error.
I have an app that uses NSPersistentCloudKitContainer stored in a shared location via App Groups so my widget can fetch data to display. It works. But if you reset your iPhone and restore it from a backup, an error occurs:
The file "Name.sqlite" couldn't be opened. I suspect this happens because the widget is created before the app's data is restored. Restarting the iPhone is the only way to fix it though, opening the app and reloading timelines does not. Anything I can do to fix that to not require turning it off and on again?
I'm using a Mac Studio in a homelab context and use Homebrew to manage the installed services. The services include things that access the local network, for example Prometheus which monitors some other servers, a reverse proxy which fronts other web services on the network, and a DNS server which can use another as upstream.
Local Network Access permissions make it impossible to reliably perform unattended updates of services because an updated binary requires a GUI login to grant local network permissions (again).
I use brew services to manage the services as launchd agents, i.e. they run in a non-root GUI context. I know that I can also use sudo brew services which instead installs the services as launchd daemons, but running services as root has negative security implication and generally doesn't look like a good idea to me.
If only there was a way to disable local network access checks altogether…
I'm writing a read-only filesystem extension.
I see that the documentation for loadResource(resource:options:replyHandler:) claims that the --rdonly option is supported, which suggests that this should be possible. However, I have never seen this option provided to my filesystem extension, even if I return usableButLimited as a probe result (where it doesn't mount at all - FB19241327) or pass the -r or -o rdonly options to the mount(8) command. Instead I see those options on the volume's activate call.
But other than saving that "readonly" state (which, in my case, is always the case) and then throwing on all write-related calls I'm not sure how to actually mark the filesystem as "read-only." Without such an indicator, the user is still offered the option to do things like trash items in Finder (although of course those operations do not succeed since I throw an EROFS error in the relevant calls).
It also seems like the FSKit extensions that come with the system handle read-only strangely as well. For example, for a FAT32 filesystem, if I mount it like
mount -r -F -t msdos /dev/disk15s1 /tmp/mnt
Then it acts... weirdly. For example, Finder doesn't know that the volume is read-only, and lets me do some operations like making new folders, although they never actually get written to disk. Writing may or may not lead to errors and/or the change just disappearing immediately (or later), which is pretty much what I'm seeing in my own filesystem extension. If I remove the -F option (thus using the kernel extension version of msdos), this doesn't happen.
Are read-only filesystems currently supported by FSKit? The fact that extensions like Apple's own msdos also seem to act weirdly makes me think this is just a current FSKit limitation, although maybe I'm missing something. It's not necessarily a hard blocker given that I can prevent writes from happening in my FSKit module code (or, in my case, just not implement such features at all), but it does make for a strange experience.
(I reported this as FB21068845, although I'm mostly asking here because I'm not 100% sure this is not just me missing something.)
When I've tried to use UIDevice on my Mac running my Catalyst application, testing code
UIDevice *d=UIDevice.currentDevice;
for (NSString *k in @[@"name", @"systemName", @"systemVersion", @"model", @"localizedModel"])
NSLog(@"%@ -> %@", k, [d valueForKey:k]);
to my great surprise I am getting
name -> iPad
systemName -> iPadOS
systemVersion -> 26.3
model -> iPad
localizedModel -> iPad
What the. How do I determine the real values? Thanks!
A user of my app reported that when my app copies files from a QNAP NAS to a folder on their Mac, they get the error "Result too large". When copying the same files from the Desktop, it works.
I asked them to reproduce the issue with the sample code below and they confirmed that it reproduces. They contacted QNAP for support who in turn contacted me saying that they are not sure they can do anything about it, and asking if Apple can help.
Both the app user and QNAP are willing to help, but at this point I'm also unsure how to proceed. Can someone at Apple say anything about this? Is this something QNAP should solve, or is this a bug in macOS?
P.S.: I've had users in the past who reported the same issue with other brands, mostly Synology.
import Cocoa
@main
class AppDelegate: NSObject, NSApplicationDelegate {
func applicationDidFinishLaunching(_ aNotification: Notification) {
let openPanel = NSOpenPanel()
openPanel.canChooseDirectories = true
openPanel.runModal()
let source = openPanel.urls[0]
openPanel.canChooseFiles = false
openPanel.runModal()
let destination = openPanel.urls[0]
do {
try copyFile(from: source, to: destination.appendingPathComponent(source.lastPathComponent, isDirectory: false))
} catch {
NSAlert(error: error).runModal()
}
NSApp.terminate(nil)
}
private func copyFile(from source: URL, to destination: URL) throws {
if try source.resourceValues(forKeys: [.isDirectoryKey]).isDirectory == true {
try FileManager.default.createDirectory(at: destination, withIntermediateDirectories: false)
for source in try FileManager.default.contentsOfDirectory(at: source, includingPropertiesForKeys: nil) {
try copyFile(from: source, to: destination.appendingPathComponent(source.lastPathComponent, isDirectory: false))
}
} else {
try copyRegularFile(from: source, to: destination)
}
}
private func copyRegularFile(from source: URL, to destination: URL) throws {
let state = copyfile_state_alloc()
defer {
copyfile_state_free(state)
}
var bsize = UInt32(16_777_216)
if copyfile_state_set(state, UInt32(COPYFILE_STATE_BSIZE), &bsize) != 0 {
throw NSError(domain: NSPOSIXErrorDomain, code: Int(errno))
} else if copyfile_state_set(state, UInt32(COPYFILE_STATE_STATUS_CB), unsafeBitCast(copyfileCallback, to: UnsafeRawPointer.self)) != 0 {
throw NSError(domain: NSPOSIXErrorDomain, code: Int(errno))
} else if copyfile(source.path, destination.path, state, copyfile_flags_t(COPYFILE_DATA | COPYFILE_SECURITY | COPYFILE_NOFOLLOW | COPYFILE_EXCL | COPYFILE_XATTR)) != 0 {
throw NSError(domain: NSPOSIXErrorDomain, code: Int(errno))
}
}
private let copyfileCallback: copyfile_callback_t = { what, stage, state, src, dst, ctx in
if what == COPYFILE_COPY_DATA {
if stage == COPYFILE_ERR {
return COPYFILE_QUIT
}
}
return COPYFILE_CONTINUE
}
}
Hi and help needed! I updated my iPhone 16 Pro max to iOs 26. When I go to the software update section, the beta developer tab is gone, and it says "Unable to check for update"
I reset my network settings and restarted the device. No change.
Any help would be appreciated.
Topic:
App & System Services
SubTopic:
Core OS
Hello everyone,
I am migrating a legacy KEXT to a DriverKit (DEXT) architecture. While the DEXT itself is working correctly, I am completely blocked by a code signing issue when trying to establish the UserClient connection from our SwiftUI management app.
Project Goal & Status:
Our DEXT (com.accusys.Acxxx.driver) activates successfully (systemextensionsctl list confirms [activated enabled]).
The core functionality is working (diskutil list shows the corresponding disk device node).
The Core Problem: The userclient-access Signing Error
To allow the app to connect to the DEXT, the com.apple.developer.driverkit.userclient-access entitlement is required in the app's .entitlements file.
However, as soon as this entitlement is added, the build fails.
Both automatic and manual signing fail with the same error:
`Provisioning profile ... doesn't match the entitlements file's value for the ... userclient-access entitlement.`
This build failure prevents the generation of an .app bundle, making it impossible to inspect the final entitlements with codesign.
What We've Confirmed:
The necessary capabilities (like DriverKit Communicates with Drivers) are visible and enabled for our App ID on the developer portal.
The issue persists on a clean system state and on the latest macOS Sequoia 15.7.1.
Our Research and Hypothesis:
We have reviewed the official documentation "Diagnosing issues with entitlements" (TN3125).
According to the documentation, a "doesn't match" error implies a discrepancy between the entitlements file and the provisioning profile.
Given that we have tried both automatic and manual profiles (after enabling the capability online), our hypothesis is that the provisioning profile generation process on Apple's backend is not correctly including the approved userclient-access entitlement into the profile file itself. The build fails because Xcode correctly detects this discrepancy.
Our Questions:
Did we misunderstand a step in the process, or is the issue not with the entitlement request at all? Alternatively, are there any other modifications we can make to successfully connect our App to the DEXT and trigger NewUserClient?
Thank you for any guidance.
I'm encountering a strange behavior with one of my home's on Home app while I'm off network. When I launch the app it indicates that the hub is not responding and all of my devices are unavailable.
However, on the menu bar at the bottom if I switch to "Automation" and back to "Home" the pop-up goes away and my devices are accessible again (sometimes this take a few attempts). Siri is also able to consistently control my devices without an issue.
The same behavior occurs with Home app on other devices (e.g. Mac) and with other members that have access to the household. 3rd party HomeKit app like "Controller" does not have an issue.
This issue began with iOS 26 and I haven't had much luck resolving the issue. I already tried rebooting everything, including removing and re-adding an Apple TV (home hub). I have other homes shared with me in Home App with similar network/environment that are still working. The home I'm having issues has the most number of devices though (over 100+).
I need to detect the triggering of an auto-mount operation when accessing the path to a formerly unknown mount point at the file system (BSD, POSIX, NSURL) level, and how to wait for it to finish the operation.
Network shares can have sub-volumes on them
Consider a Windows server. Let's say there's a SMB sharepoint at C:\Shared. It has some folders, one of which is at C:\Shared\More. Furthermore, there's another partition (volume) on the PC, which is mounted at C:\Shared\More\OtherVol.
If you mount the initial share on a Mac with a recent macOS, macOS initially only sees a single mount point at /Volumes/Shared, which can be checked with the "mount" command.
Now, if you use Finder to dive into the Shared/More folder, Finder will trigger an auto-mount action on the containing OtherVol folder, and after that, the "mount" command will list two mount points from this server, the second being at /Volumes/Shared/More/OtherVol.
(This was a bit surprising to me - I'd have thought that Windows or SMB would hide the fact that the share has sub-volumes, and simply show them as directories - and that's what it did in older macOS versions indeed, e.g. in High Sierra. But in Sequoia, these sub-volumes on the Windows side are mirrored on the Mac side, and they behave accordingly)
Browse the volume, including its sub-volumes
Now, I have a program that tries to dive into all the folders of this Shared volume, even if it was just freshly mounted and there's no mountpoint at /Volumes/Shared/More/OtherVol known yet (i.e. the user didn't use Finder to explore it).
This means, that if my program, e.g. using a simple recursive directory scan, reaches /Volumes/Shared/More/OtherVol, the item will not appear as a volume but as an empty folder. E.g, if I get the NSURLIsVolumeKey value, it'll be false. Only once I try to enter the empty dir, listing its contents, which will return no items, an auto-mount action will get triggered, which will add the mountpoint at the path.
So, in order to browse the actual contents of the OtherVol directory, I'd have to detect this auto-mount operation somehow, wait for it to finish mounting, and then re-enter the same directory so that I now see the mounted content.
How do I do that? I.e. how do I tell that a dir is actually a auto-mount point and how do I wait for it to get auto-mounted before I continue to browse its contents?
Note that newer macOS versions do not use fstab any more, so that's of no help here.
Can the DA API help?
Do I need to use the old Disk Arbitration functions for this, somehow?
I have used the DA framework in the part to prevent auto-mounting, so I imagine I could hook into that handler, and if I get a callback for a mount operation, I could then queue the newly mounted volume for scanning. The problem, however, is that my scanning code may, having only seen an empty directory at the not-yet-mounted mountpoint, already decided that there's nothing there and finished its operation.
I'd need some reliable method that lets my recursive scanning code know whether an auto-mount has been triggered and it therefore needs to wait for the DA callback.
So, is there some signal that will let me know IMMEDIATELY after entering the empty mountpoint directory that an auto-mount op is on the way? Because I suspect that the DA callbacks come with a delay, and therefore would come too late if I used that as the notifier that I have to wait.
Hello,
Title states it basically. I have a java program (launched via shell script) running as a service using launchd which is running as a user (not root) and it does not request Local Network permissions ever.
I feel like i'm missing something here. I combed through all of the Local Network FAQs and don't really see this use case addressed.
I do see that there is an open ticket for an API to trigger the request, but no update on that and the ticket is not visible publicly.
Is there is a way to accomplish this for java or other programs running via launchd with a user other than root? something like an entitlement or an API to seed the permission of Local Network when installing the service via launchctl etc?
I have this code in my Virutalization application
let process = Process()
process.executableURL = URL(fileURLWithPath: "/usr/sbin/diskutil")
process.arguments = ["image", "create", "blank",
"--fs", "none", "--format",
"ASIF", "--size", "2GiB",
url.path
]
try process.run()
process.waitUntilExit()
if process.terminationStatus == 0 {
print("✅ Disk image creation succeeded.")
} else {
print("❌ Disk image creation failed with exit code \(process.terminationStatus)")
}
} catch {
print("Process failed to launch: \(error.localizedDescription)")
return
}
this code was working fine until Tahoe 26.2. with the update of 26.3 the system freezes at process.waitUntilExit()
The code never exits and i get beech balls. This is working fine with intel macs. i am getting the problem in apple silicon m4 mac mini.
Any help would be appreciated.
I'll try to ask a question that makes sense this time :) . I'm using the following method on NSFileManager:
(BOOL) getRelationship:(NSURLRelationship *) outRelationship
ofDirectoryAtURL:(NSURL *) directoryURL
toItemAtURL:(NSURL *) otherURL
error:(NSError * *) error;
Sets 'outRelationship' to NSURLRelationshipContains if the directory at 'directoryURL' directly or indirectly contains the item at 'otherURL', meaning 'directoryURL' is found while enumerating parent URLs starting from 'otherURL'. Sets 'outRelationship' to NSURLRelationshipSame if 'directoryURL' and 'otherURL' locate the same item, meaning they have the same NSURLFileResourceIdentifierKey value. If 'directoryURL' is not a directory, or does not contain 'otherURL' and they do not locate the same file, then sets 'outRelationship' to NSURLRelationshipOther. If an error occurs, returns NO and sets 'error'.
So this method falsely returns NSURLRelationshipSame for different directories. One is empty, one is not. Really weird behavior. Two file path urls pointing to two different file paths have the same NSURLFileResourceIdentifierKey? Could it be related to https://developer.apple.com/forums/thread/813641 ?
One url in the check lived at the same file path as the other url at one time (but no longer does). No symlinks or anything going on. Just plain directory urls.
And YES calling -removeCachedResourceValueForKey: with NSURLFileResourceIdentifierKey causes proper result of NSURLRelationshipOther to be returned. And I'm doing the check on a background queue.