General: DevForums subtopic: App & System Services > Core OS Core OS is a catch-all subtopic for low-level APIs that don’t fall into one of these more specific areas: Processes & Concurrency Resources Files and Storage Resources Networking Resources Network Extension Resources Security Resources Virtualization Resources Share and Enjoy — Quinn “The Eskimo!” @ Developer Technical Support @ Apple let myEmail = "eskimo" + "1" + "@" + "apple.com"

Hello, I am working on a cross‑platform application that uses libiconv to convert strings to/from Unicode. I need to modify the existing code for compatibility with macOS. However, the call to iconv() fails with an unclear errno value (92) when using "WCHAR_T": std::wstring ConvertToWchar(const std::string& iconvCodeSet, const std::string_view str) { iconv_t conv = iconv_open("WCHAR_T//TRANSLIT", iconvCodeSet.c_str()); if (conv == (iconv_t)-1) { std::cerr << "iconv_open() failed" << std::endl; return {}; } std::wstring out(str.size(), L'\0'); auto inPtr = (char*)str.data(); size_t inSize = str.size(); auto outPtr = (char*)out.data(); size_t outSize = out.size() * sizeof(wchar_t); if (iconv(conv, &inPtr, &inSize, &outPtr, &outSize) == (size_t)-1) { std::cerr << "iconv() failed. errno = " << errno << std::endl; return {}; } if (iconv(conv, nullptr, &inSize, &outPtr, &outSize) == (size_t)-1) { std::cerr << "iconv() failed. errno = " << errno << std::endl; return {}; } iconv_close(conv); return out; } int main() { std::string str1((const char*)u8"ΟΔΥΣΣΕΥΣ"); std::wstring str2 = ConvertToWchar("UTF-8", str1); if (str2.empty()) return 1; std::cout << "converted" << std::endl; return 0; } Using "UTF-32" works fine, but "WCHAR_T//TRANSLIT" fails. What is the recommended way to convert wchar_t strings using libiconv? Why does the conversion fail with "WCHAR_T//TRANSLIT"? Thank you in advance!

We are observing a reproducible issue on some (not all) iPad models equipped with A16, where BLE streaming from multiple peripherals at ≥33–40 Hz results in uneven packet distribution, burst delivery, and application-level lag. The same application, peripherals, firmware, iOS version, and physical environment do not exhibit this behaviour on A14-based iPads (iPad 10). Affected Hardware: • iPad 11" with A16 • iOS versions: identical across tested devices • Issue affects some devices of the same model, not all Internal field data • ~25 affected • ~5 unaffected • Customers actively prefer iPad 10 (A14) due to stability When two or more BLE peripherals stream data concurrently at frequencies ≥33–40 Hz, affected iPads exhibit: • Uneven packet arrival timing • Burst delivery instead of uniform intervals • Increasing latency over time • Observable application-level lag This does not present as simple packet loss. Instead, packets arrive in clusters, breaking real-time assumptions. At ≤30–33 Hz, the issue does not reproduce. We tested: • One affected iPad 11 • One unaffected iPad 11 • Same iOS version • Same app build • Same peripherals • Same firmware • Same physical location • Same Wi-Fi state Only the affected device reproduces the issue. This rules out: • App logic • Peripheral firmware • iOS version • Environmental RF noise • Wi-Fi coexistence configuration Evidence Available We can provide: • Screenshots from a minimal test app showing packet counts • CSV files of packet timestamps • Source code for the BLE test app • Side-by-side comparison logs (affected vs unaffected device) All evidence is from the same app, built solely to measure packet timing. Additional Technical Notes • Issue persists after factory reset • Occurs without third-party BLE libraries (CoreBluetooth only) • Occurs regardless of foreground/background state • Not correlated with MTU size • Appears threshold-based (~33–40 Hz) • Appears device-specific, not model-wide

If there is this situation: A text message is sent from a sender and gets classified as junk (by a text filtering extension) with the result that it gets send to the spam folder as expected. A text message with different content is sent from the same sender and gets classified as allowed, however it also gets sent to the spam folder. If the above is repeated but after step 1 the message is deleted, then in step 2 the message doesn't get sent to the spam folder. So the presence of the message from step 1 being in the spam folder is having an effect on the behavior of step 2. Expected beahavour (if so, why?), or a defect?

On macOS Tahoe, our application using the Endpoint Security Framework (ESF) observes that during file copies through finder application, DesktopServicesHelper unlinks the source file if the ESF authorization response is delayed for ~5 seconds, even though the authorization event deadline remains 15 seconds, indicating that the process does not wait for the full ESF deadline before deleting the file. Before Tahoe, we didnt see this behaviour.

Switching alternative app icons previously worked in my app and I did not notice when it broke. However now the completion handler consistently returns this error if feeding with either an existing app icon name or a fictional one. Is this a regression I should file a bug report for or am I doing something wrong here? Include all app icon assets is enabled in the target Below you can see the error, the .icon files placed in the project navigator, my code and the top of the Info.plist Thank you Button("Update icon") { UIApplication.shared.setAlternateIconName("appIcon_Heart") { error in if let error { print(error) } } } Error Domain=NSPOSIXErrorDomain Code=35 "Resource temporarily unavailable" UserInfo={_LSFile=LSIconAlertManager.m, _LSLine=113, _LSFunction=-[LSIconAlertManager iconChangeAlertTokenForIdentity:error:]} Xcode seems to create the correct Info.plist entries. <?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd"> <plist version="1.0"> <dict> <key>BGTaskSchedulerPermittedIdentifiers</key> <array> <string>newReleasesBackgroundTask</string> </array> <key>BuildMachineOSBuild</key> <string>24G90</string> <key>CFBundleDevelopmentRegion</key> <string>de</string> <key>CFBundleDisplayName</key> <string>Hörspielzentrale</string> <key>CFBundleExecutable</key> <string>Hoerspielzentrale</string> <key>CFBundleIcons</key> <dict> <key>CFBundleAlternateIcons</key> <dict> <key>appIcon_Heart</key> <dict> <key>CFBundleIconName</key> <string>appIcon_Heart</string> </dict> <key>appIcon_RedNoCircle</key> <dict> <key>CFBundleIconName</key> <string>appIcon_RedNoCircle</string> </dict> <key>appIcon_WhiteNoCircle</key> <dict> <key>CFBundleIconName</key> <string>appIcon_WhiteNoCircle</string> </dict> </dict> <key>CFBundlePrimaryIcon</key> <dict> <key>CFBundleIconFiles</key> <array> <string>AppIcon60x60</string> </array> <key>CFBundleIconName</key> <string>AppIcon</string> </dict> </dict> <key>CFBundleIcons~ipad</key> <dict> <key>CFBundleAlternateIcons</key> <dict> <key>appIcon_Heart</key> <dict> <key>CFBundleIconName</key> <string>appIcon_Heart</string> </dict> <key>appIcon_RedNoCircle</key> <dict> <key>CFBundleIconName</key> <string>appIcon_RedNoCircle</string> </dict> <key>appIcon_WhiteNoCircle</key> <dict> <key>CFBundleIconName</key> <string>appIcon_WhiteNoCircle</string> </dict> </dict> <key>CFBundlePrimaryIcon</key> <dict> <key>CFBundleIconFiles</key> <array> <string>AppIcon60x60</string> <string>AppIcon76x76</string> </array> <key>CFBundleIconName</key> <string>AppIcon</string> </dict> </dict>

Has anyone else run across this after manually renewing an expired developer account? Happens when I go to the "Certificates, Identifiers, &amp; Profiles" page and click on anything. Also unable to download any of the iOS SDK's. Any ideas?

Hi! I'm trying to figure out what mechanism request stop sends to the guest to actually request a stop. It doesn't appear that Virtualization.framework implements any ACPI bits relating to power buttons, so unclear how a linux VM would detect that a request has been stopped. I don't see any documentation around what devices are implemented by Virtualization.framework either, in terms of things like realtime clock, etc. Thanks for any help!

Hello Everyone, I'm trying to add badges to files in my File Provider Extension for macOS. I'm not trying to create my own Item decorations here, but use the default Icons provided by apple (such as com.apple.icon-decoration.badge.heart , com.apple.icon-decoration.badge.pinned). I've gone through the Sample code provided by Apple for Fruit Basket. I've tried to replicate the same thing in my Extension as well but It seems I'm unable to display Icons. I'm not even getting any Error when the Icons are not being displayed, So I've been stuck for a month on this. These are the Things that I've done below: Folder Structure : FileExplorer |- FileProviderApp | |- UI.swift | |- ContentView.swift |- Extension |- extension.swift |- item.swift |- enumerator.swift |- info.plist According to the instructions given in the Documentation for Decorations here : https://developer.apple.com/documentation/fileprovider/nsfileprovideritemdecorating. The implementation was done as follows: content inside info.plist of the File provider Extension <!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd"> <plist version="1.0"> <dict> <key>NSExtension</key> <dict> <key>NSExtensionFileProviderSupportsEnumeration</key> <true/> <key>NSExtensionPointIdentifier</key> <string>com.apple.fileprovider-nonui</string> <key>NSExtensionPrincipalClass</key> <string>$(PRODUCT_MODULE_NAME).FileProviderExtension</string> <key>NSFileProviderDecorations</key> <array> <dict> <key>BadgeImageType</key> <string>com.apple.icon-decoration.badge.heart</string> <key>Category</key> <string>Badge</string> <key>Identifier</key> <string>$(PRODUCT_BUNDLE_IDENTIFIER).heart</string> <key>Label</key> <string>Heart Item</string> </dict> </array> </dict> </dict> </plist> In my extension's NSFileProviderItem I've also Implemented the protocol NSFileProviderItemDecorating. and the decoration's method as static let decorationPrefix = Bundle.main.bundleIdentifier! static let heartDecoration = NSFileProviderItemDecorationIdentifier(rawValue: "\(decorationPrefix).heart") var decorations: [NSFileProviderItemDecorationIdentifier]? { var decos = [NSFileProviderItemDecorationIdentifier]() decos.append(Item.heartDecoration) return decos } I was expecting to see badges on the File items in Finder, but i got nothing. When I modified the FruitBasket Project to do the same i was able to see badges, but not when I try to implement it in my Extension. Was I missing a step or is the issue something else ?

We are observing some unexpected behavior in our app when using ASK. Our app is able to successfully discover and set up an accessory via ASK. After the setup completes, the connection to the accessory is managed through CBCentralManager and works as expected. However, when we attempt to discover another accessory afterward, the picker is shown and indicates that accessory discovery is in progress. After approximately 10 seconds, the CBCentralManager delegate reports the Bluetooth state as poweredOff. Once this happens, the state never transitions back to poweredOn. At this point, the only way to reconnect to the device or continue discovery is to relaunch the app. We are wondering if anyone else has encountered similar behavior, or if this is a known or documented limitation/behavior when using ASK in combination with CBCentralManager.

On a MacBook Pro, 16GB of RAM, 500 GB SSD, OS Sequoia 15.7.1, M3 chip, I am running some python3 code in a conda environment that requires lots of RAM and sure enough, once physical memory is almost exhausted, swapfiles of about 1GB each start being created, which I can see in /System/Volumes/VM. This folder has about 470 GB of available space at the start of the process (I can see this through get info) however, once about 40 or so swapfiles are created, for a total of about 40GB of virtual memory occupied (and thus still plenty of available space in VM), zsh kills the python process responsible for the RAM usage (notably, it does not kill another python process using only about 100 MB of RAM). The message received is "zsh: killed" in the tmux pane where the logging of the process is printed. All the documentation I was able to consult says that macOS is designed to use up to all available storage on the startup disk (which is the one I am using since I have only one disk and the available space aforementioned reflects this) for swapping, when physical RAM is not enough. Then why is the process killed long before the swapping area is exhausted? In contrast, the same process on a Linux machine (basic python venv here) just keeps swapping, and never gets killed until swap area is exhausted. One last note, I do not have administrator rights on this device, so I could not run dmesg to retrieve more precise information, I can only check with df -h how the swap area increases little by little. My employer's IT team confirmed that they do not mess with memory usage on managed profiles, so macOS is just doing its thing. Thanks for any insight you can share on this issue, is it a known bug (perhaps with conda/python environments) or is it expected behaviour? Is there a way to keep the process from being killed?

Hello, We're developing endpoint security software using the Endpoint Security framework, and we've encountered challenges with the behavior change in macOS 15 regarding provisioning UDIDs in cloned VMs. The Change Prior to macOS 15, cloning a VM preserved its UDID (format: 0000FE00-9C4ED9F68BBDC72D). Starting with macOS 15, cloned VMs receive a new UDID generated from the host's Secure Enclave (format: b043d27202c7ac37ca3c6b82673302225485cae9), making each clone effectively a new device. Our Workflow We maintain a clean base VM image and clone it for each test run. We add the base VM's UDID to our provisioning profile once, then create clones which (previously) retained that same UDID, allowing us to start new testing cycles without re-registering devices. This is essential because our product involves low-level system integration through the Endpoint Security framework, and if something goes wrong during development, it has the potential to affect system stability. To prevent any cascading issues between test runs or different product versions, we need each test to start from a known clean state rather than reusing the same VM. The Challenge With each VM clone generating a new UDID, we're hitting Apple's device registration limits quickly. This particularly impacts: New team members who spin up VMs for the first time and can't run signed builds Our CI/CD pipeline where multiple test environments need provisioning profiles Developers testing different branches who need separate clean environments Current Workaround We've found that VMs created on macOS 14 and upgraded to macOS 15+ retain their original UDID format. However, we're concerned this workaround may stop working in future macOS versions, which would leave us without a viable path forward. If the workaround stops working, our fallback would be signing each CI build with a Developer ID signature to allow running on any device. However, we'd prefer to avoid this as it would significantly increase load on Apple's signing infrastructure for what are essentially internal test builds. We completely understand the security reasoning behind tying UDIDs to the host's Secure Enclave for Apple Account support. However, for development workflows that don't require Apple Account features in VMs but do require clean, isolated test environments, the previous behavior was quite valuable. Question Is there a recommended approach for teams in our situation? We're happy to explore alternative workflows if there's a pattern we're missing, or we'd be glad to provide more context if this is a use case Apple is considering for future updates. Thanks for any guidance you can provide! Feedback case: FB21389730

I'm trying to debug an issue with the Valgrind tool Helgrind. This is on masOS 11 (I've also seen it on 12, probably the same for other macOS versions). Here is the testcase. #include <pthread.h> #include <string.h> #include <assert.h> #include <errno.h> int main(void) { pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER; pthread_cond_t cond = PTHREAD_COND_INITIALIZER; int res; // This time has most definitely passed already. (Epoch) struct timespec now; memset(&now, 0, sizeof(now)); res = pthread_mutex_lock(&mutex); assert(res == 0); res = pthread_cond_timedwait(&cond, &mutex, &now); assert(res == ETIMEDOUT); res = pthread_mutex_unlock(&mutex); assert(res == 0); res = pthread_mutex_destroy(&mutex); assert(res == 0); res = pthread_cond_destroy(&cond); assert(res == 0); } The error that I'm getting from Helgrind is ==56754== Thread #1 unlocked a not-locked lock at 0x1048C7A08 ==56754== at 0x10020E2F9: mutex_unlock_WRK (hg_intercepts.c:1255) ==56754== by 0x10020E278: pthread_mutex_unlock (hg_intercepts.c:1278) ==56754== by 0x7FF80F526813: _pthread_cond_wait (in /usr/lib/system/libsystem_pthread.dylib) ==56754== by 0x10020E812: pthread_cond_timedwait_WRK (hg_intercepts.c:1465) ==56754== by 0x10020E6A8: pthread_cond_timedwait (hg_intercepts.c:1512) ==56754== by 0x100003DD2: main (cond_timedwait_test.c:18) ==56754== Lock at 0x1048C7A08 was first observed ==56754== at 0x10020DE91: mutex_lock_WRK (hg_intercepts.c:1009) ==56754== by 0x10020DD68: pthread_mutex_lock (hg_intercepts.c:1031) ==56754== by 0x100003D7D: main (cond_timedwait_test.c:16) ==56754== Address 0x1048c7a08 is on thread #1's stack ==56754== in frame #5, created by main (cond_timedwait_test.c:7) If I turn on extra tracing then on FreeBSD the Helgrind pthread traces correspond to the C source. On macOS I see an extra mutex. << pthread_mxlock 0x7ff850c41 :: mxlock -> 0 >> << pthread_mxunlk 0x7ff850c41 :: mxunlk -> 0 >> ^^ I don't know what this mutex is << pthread_mxlock 0x1048c7a08 :: mxlock -> 0 >> ^^ this is the user mutex << pthread_mxlock 0x7ff850c41 :: mxlock -> 0 >> << pthread_cond_timedwait 0x1048c79d8 0x1048c7a08 0x1048c79c0<< pthread_mxunlk 0x7ff850c41 :: mxunlk -> 0 >> ^^ pthread_cond_timedwait unlocking the non-user mutex << pthread_mxlock 0x7ff850c41 :: mxlock -> 0 >> << pthread_mxunlk 0x7ff850c41 :: mxunlk -> 0 >> << pthread_mxunlk 0x1048c7a08 [error here] :: mxunlk -> 0 >> << pthread_mxlock 0x1048c7a08 :: mxlock -> 0 >> << pthread_mxlock 0x7ff850c41 :: mxlock -> 0 >> cotimedwait -> 60 >> In these traces the "-> 0" is the return code, showing that all of the calls succeeded. I need to do more debugging inside Helgrind. In the traces above I only see the user mutex being locked and then unlocked. Can anyone explain why I'm seeing an extra mutex in there? I'll have a poke around the XNU source

I'm having problems constructing the initial stack for the guest executable for Valgrind on macOS 12 Intel. This seemed to work OK for macOS 11 but I'm getting a bad 'apple' pointer on macOS 12. The stack (constructed by Valgrind) looks like this higher address +-----------------+ <- clstack_end | | : string table : | | +-----------------+ | NULL | +-----------------+ | executable_path | (first arg to execve()) +-----------------+ | NULL | - - | envp | +-----------------+ | NULL | - - | argv | +-----------------+ | argc | +-----------------+ | mach_header * | (dynamic only) lower address +-----------------+ <- sp | undefined | : : The problem that I'm having is with the executable path (or the apple pointer). This points to NULL. The actual pointer to the "executable=xxx" string is 16 bytes lower in memory. The code for main starts with Dump of assembler code for function main: 0x0000000100003a90 <+0>: push %rbp 0x0000000100003a91 <+1>: mov %rsp,%rbp 0x0000000100003a94 <+4>: sub $0x60,%rsp 0x0000000100003a98 <+8>: movl $0x0,-0x4(%rbp) 0x0000000100003a9f <+15>: mov %edi,-0x8(%rbp) 0x0000000100003aa2 <+18>: mov %rsi,-0x10(%rbp) 0x0000000100003aa6 <+22>: mov %rdx,-0x18(%rbp) 0x0000000100003aaa <+26>: mov %rcx,-0x20(%rbp) That's the prefix, making space for locals, setting a local variable to 0 then getting the 4 arguments from main in edi, rsi, rdx and rcx as per the SYSV amd64 ABI. I think that it is dyld that puts the apple pointer into rcx. Can anyone tall me how dyld works out the address of the apple pointer?

Hi, I am developing a NSReplicatedFileProvider extension. Part of that I am also doing a Finder Sync Extension, but I am for whatever reason unable to enable the extension. What am I missing? it is signed properly, it has the right app group. Is there anything else I nede to enable for it? When I do this: pluginkit -m | grep -i XXXFinderSync I get com.clio.XXX-Desktop.XXXFinderSync(1.0) Not that - shows up as bullet point. The hyphen signifies it is disabled.

On the macOS platform, I am planning to use the combination of NSFileProviders Custom Action and userInfo to implement custom context menus. However, the NSExtensions FileProviders Action Activation Rule in info does not work as long as it is related to userInfo. Are there any restrictions on the use of this userInfo? keepDownloaded is bool value

Currently tested, if the file provider goes offline (referring to calling disconnect) and deletes a file, the system will automatically trigger the deleteItems event after reconnecting (note that only after calling reconnect again will the current deleteItems logic be reached). However, for offline deletion, I would like to pass it directly without operating on the cloud. Can mounting disks determine which operations were performed offline during reboot

System Version: 26.1 Device: M1 Mac Mini Steps to Reproduce: Create a UNIX socket file at /tmp/a.sock Execute the command: ln /tmp/a.sock /tmp/b.sock Execute the command: rm /tmp/b.sock Bug Description: At this point, a bug occurs in the ES_EVENT_TYPE_AUTH_UNLINK event of the system extension. The value returned for message->event.unlink.target->path is /tmp/a.sock, while it is expected to be /tmp/b.sock Reproducibility: 100%

Hi all, I’m building an iOS app that uses CoreNFC to communicate with a YubiKey 5C NFC over ISO14443 / ISO7816 and send APDUs (e.g. select an applet by AID). Environment • Device: iPhone 13 Pro Max • iOS: 18.6.2 • Xcode: 26.1.1 (17B100) • API: NFCTagReaderSession(pollingOption: .iso14443) using NFCTag.iso7816 What I’m trying to do 1. Start NFCTagReaderSession(.iso14443) 2. Detect tag → connect 3. Send ISO7816 APDUs (SELECT AID, etc.) Issue A — Entitlements / signing If I add ISO7816-related NFC entitlements, Xcode fails signing with an error like: • “Provisioning profile … doesn’t match entitlements file value for com.apple.developer.nfc.readersession.formats” When I inspect the generated .mobileprovision, I only see something like: • com.apple.developer.nfc.readersession.formats = [NDEF, TAG, PACE] …and I do not see an ISO7816 / select-identifiers entitlement (and the Developer portal UI doesn’t appear to let me enable it). Questions: 1. Is ISO7816 access under com.apple.developer.nfc.readersession.formats restricted and requires Apple approval? If yes, what’s the correct request process? 2. Is com.apple.developer.nfc.readersession.iso7816.select-identifiers required for sending ISO7816 APDUs? If yes, how do developers obtain it / enable it for an App ID + provisioning profiles? 3. What is the Apple-supported way to configure entitlements/profiles for CoreNFC ISO7816 APDU communication with a token like a YubiKey? Issue B — Runtime NFC error Separately (even when I can run), I intermittently/consistently get: • NFCError Code=104 (“Tag is not connected”) This occurs after the tag is detected/connected when trying to establish a session or send APDUs. I’ve verified: • No phone case interference • Correct placement • Consistent detection “tick” from the phone for "Ready to Scan" prompt after tapping YubiKey 5C NFC device. If helpful, I can share: • A minimal sample project • The exact entitlements I tried • Console logs around the Code 104 failure Thanks!

I am currently encountering a problem: during the process of uploading a large file, I have moved the file that was not successfully uploaded to the trash can. These two operations have been tested to be serial (triggering the 'create Item' callback first, followed by the 'modify Item' callback), which means that the file must be uploaded before it can be moved to the recycle bin (which can also result in the file being stored in the cloud recycle bin). I want to implement: directly interrupt this upload process and then do not complete the upload. How can I achieve this? Please help me. Thank you