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iphone mirroring
Hi Team , I want to create a system where i can mirror the iPhone screen connected through USB and control it from the web browser. can anyone help me ? Thanks , Mukta
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366
Jan ’25
The Map() of IOBufferMemoryDescriptor failure and cause the DriverKit Start() repeat
Hello Everyone, I am trying to develop a DriverKit for RAID system, using PCIDriverKit & SCSIControllerDriverKit framework. The driver can detect the Vendor ID and Device ID. But before communicating to the RAID system, I would like to simulate a virtual Volume using a memory block to talk with macOS. In the UserInitializeController(), I allocated a 512K memory for a IOBufferMemoryDescriptor* volumeBuffer, but fail to use Map() to map memory for volumeBuffer. result = ivars->volumeBuffer->Map( 0, // Options: Use default 0, // Offset: Start of the buffer ivars->volumeSize, // Length: Must not exceed buffer size 0, // Flags: Use default nullptr, // Address space: Default address space &mappedAddress // Output parameter ); Log("Memory mapped completed at address: 0x%llx", mappedAddress); // this line never run The Log for Map completed never run, just restart to run the Start() and makes this Driver re-run again and again, in the end, the driver eat out macOS's memory and system halt. Are the parameters for Map() error? or I should not put this code in UserInitializeController()? Any help is appreciated! Thanks in advance. Charles
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358
Mar ’25
CoreAudio server plugin: updating kAudioStreamPropertyAvailablePhysicalFormats
Hi, our CoreAudio server plugin supports different clock sources. A switch might result in a change of the selectable sample rates (and other settings). On a clock source switch the plugin reconfigures the set of available kAudioStreamPropertyAvailablePhysicalFormats and announces the change via AudioServerPlugInHostInterface::PropertiesChanged(). However at least the Audio MIDI Setup seems to ignore to update it's UI. The changes are first reflected after selecting another device and re-selecting the device of interest. (Latest macOS, M4 macMini) Is this a bug? Or is our CoreAudio server plugin required to indicate the change in the list of available audio formats differently? Thanks!
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76
May ’25
CarPlay Simulator: How to Change Dock Position for Right-Hand Drive (RHD)
Hello everyone, I'm developing a CarPlay app and am trying to test it with the dock on the right side of the screen, as is standard for right-hand drive vehicles like those in Japan. Currently, the CarPlay Simulator always displays the dock on the left, and I can't find an option to change its position. This is important for ensuring a proper user experience for my target market. Has anyone figured out how to configure the simulator for RHD layouts? Any guidance on how to move the dock to the right would be greatly appreciated. Thanks in advance for your help!
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66
Sep ’25
USB Control Transfers on Devices with CDC Serial Port
I have a USB-device with three interfaces: Vendor-Specific Bulk CDC Serial Control CDC Serial Data To configure the vendor specific bulk endpoints I need to send vendor specific control requests to endpoint 0. I'm using libusb for this task. As long as the interfaces for the CDC serial port are present I get an access error when trying to send vendor control requests. If I disable these CDC interfaces I can send vendor control request without any problems: Is this by design or ist there any possibility to send vendor control requests to the USB device while a CDC driver is active?
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58
Oct ’25
How to sign a DEXT
Note: This is an initial draft of a post attempting to describe the details of how to sign DEXTs. While you are free to post general questions or comments, please post any questions about your specific issues as a separate thread. The question of "how do I sign a DEXT" comes up a lot, so this post is my attempt to describe both what the problems and the best solutions are. So: The Problems: When DEXTs were originally introduced, the recommended development signing process required disabling SIP and local signing. There is a newer, much simpler process that's built on Xcode's integrated code-signing support; however, that newer process has not yet been integrated into the documentation library. In addition, while the older flow still works, many of the details it describes are no longer correct due to changes to Xcode and the developer portal. DriverKit's use of individually customized entitlements is different than the other entitlements on our platform, and Xcode's support for it is somewhat incomplete and buggy. The situation has improved considerably over time, particularly from Xcode 15 and Xcode 16, but there are still issues that are not fully resolved. To address #1, we introduced "development" entitlement variants of all DriverKit entitlements. These entitlement variants are ONLY available in development-signed builds, but they're available on all paid developer accounts without any special approval. They also allow a DEXT to match against any hardware, greatly simplifying working with development or prototype hardware which may not match the configuration of a final product. Unfortunately, this also means that DEXT developers will always have at least two entitlement variants (the public development variant and the "private" approved entitlement), which is what then causes the problem I mentioned in #2. The Automatic Solution: If you're using Xcode 16 or above, then Xcode's Automatic code sign support will work for most cases. The specific flow for that is: Change the code signing configuration to "Automatic". Add the capability using Xcode. If you've been approved for one of these entitlements, the one oddity you'll see is that adding your approved capability will add both the approved AND the development variant, while deleting either will delete both. This is a visual side effect of #2 above; however, aside from the exception described below, it can be ignored. Similarly, you can sign distribution builds by creating a build archive and then exporting the build using the standard Xcode flow. The Manual Solution: NOTE: Unfortunately, I'm not confident that the flow I described below actually works today (12/5/2026). I'm leaving the information below as a useful starting point, but I'm afraid this case my require resorting to command line code signing. The approach above works for all DriverKit Entitlements, with two exceptions: USB DriverKit PCI DriverKit Both of those cases involve customized entitlement values, which then creates problems when attempting to distribute builds. Note that this is specifically about build distribution, NOT development builds. All development builds should use the flow above. The solution for these two cases is manual code signing with the export flow. Here is exactly what the flow looks like: Select the build you've archived in the Xcode Organizer and select "Distribute App". Choose "Custom" from the set of distribution methods. Choose the type of distribution (App Store or Developer ID). Choose whether to Upload or Export. Choose "Manually manage signing". Provide a profile for each of the objects that make up your app bundle. See the "Provisioning Profiles" section of Account Help for detailed instructions on that process. Continue through the rest of the process to finish build creation. Finally, a note about both of the processes above. Quoting myself: "One thing to be aware of here is that Xcode has a "bias" in the way it presents codesign errors where it assumes the Entitlement.plist is "correct" and the profile is "wrong". However, in practice that's basically "never" the case with DriverKit entitlements and tends to lead to a lot of "flailing" trying to somehow "fix" the provisioning profile..." __ Kevin Elliott DTS Engineer, CoreOS/Hardware
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11h
Implementing a virtual serial port using DriverKit/SerialDriverKit
I'm trying to implement a virtual serial port driver for my ham radio projects which require emulating some serial port devices and I need to have a "backend" to translate the commands received by the virtual serial port into some network-based communications. I think the best way to do that is to subclass IOUserSerial? Based on the available docs on this class (https://developer.apple.com/documentation/serialdriverkit/iouserserial), I've done the basic implementation below. When the driver gets loaded, I can see sth like tty.serial-1000008DD in /dev and I can use picocom to do I/O on the virtual serial port. And I see TxDataAvailable() gets called every time I type a character in picocom. The problems are however, firstly, when TxDataAvailable() is called, the TX buffer is all-zero so although the driver knows there is some incoming data received from picocom, it cannot actually see the data in neither Tx/Rx buffers. Secondly, I couldn't figure out how to notify the system that there are data available for sending back to picocom. I call RxDataAvailable(), but nothing appears on picocom, and RxFreeSpaceAvailable() never gets called back. So I think I must be doing something wrong somewhere. Really appreciate it if anyone could point out how should I fix it, many thanks! VirtualSerialPortDriver.cpp: constexpr int bufferSize = 2048; using SerialPortInterface = driverkit::serial::SerialPortInterface; struct VirtualSerialPortDriver_IVars {     IOBufferMemoryDescriptor *ifmd, *rxq, *txq;     SerialPortInterface *interface;     uint64_t rx_buf, tx_buf;     bool dtr, rts; }; bool VirtualSerialPortDriver::init() {     bool result = false;     result = super::init();     if (result != true)     {         goto Exit;     }     ivars = IONewZero(VirtualSerialPortDriver_IVars, 1);     if (ivars == nullptr)     {         goto Exit;     }     kern_return_t ret;     ret = ivars->rxq->Create(kIOMemoryDirectionInOut, bufferSize, 0, &ivars->rxq);     if (ret != kIOReturnSuccess) {         goto Exit;     }     ret = ivars->txq->Create(kIOMemoryDirectionInOut, bufferSize, 0, &ivars->txq);     if (ret != kIOReturnSuccess) {         goto Exit;     }     IOAddressSegment ioaddrseg;     ivars->rxq->GetAddressRange(&ioaddrseg);     ivars->rx_buf = ioaddrseg.address;     ivars->txq->GetAddressRange(&ioaddrseg);     ivars->tx_buf = ioaddrseg.address;     return true; Exit:     return false; } kern_return_t IMPL(VirtualSerialPortDriver, HwActivate) {     kern_return_t ret;     ret = HwActivate(SUPERDISPATCH);     if (ret != kIOReturnSuccess) {         goto Exit;     }     // Loopback, set CTS to RTS, set DSR and DCD to DTR     ret = SetModemStatus(ivars->rts, ivars->dtr, false, ivars->dtr);     if (ret != kIOReturnSuccess) {         goto Exit;     } Exit:     return ret; } kern_return_t IMPL(VirtualSerialPortDriver, HwDeactivate) {     kern_return_t ret;     ret = HwDeactivate(SUPERDISPATCH);     if (ret != kIOReturnSuccess) {         goto Exit;     } Exit:     return ret; } kern_return_t IMPL(VirtualSerialPortDriver, Start) {     kern_return_t ret;   ret = Start(provider, SUPERDISPATCH);     if (ret != kIOReturnSuccess) {         return ret;     }     IOMemoryDescriptor *rxq_, *txq_;     ret = ConnectQueues(&ivars->ifmd, &rxq_, &txq_, ivars->rxq, ivars->txq, 0, 0, 11, 11);     if (ret != kIOReturnSuccess) {         return ret;     }     IOAddressSegment ioaddrseg;     ivars->ifmd->GetAddressRange(&ioaddrseg);     ivars->interface = reinterpret_cast<SerialPortInterface*>(ioaddrseg.address);     SerialPortInterface &intf = *ivars->interface;     ret = RegisterService();     if (ret != kIOReturnSuccess) {         goto Exit;     }     TxFreeSpaceAvailable(); Exit:     return ret; } void IMPL(VirtualSerialPortDriver, TxDataAvailable) {     SerialPortInterface &intf = *ivars->interface;     // Loopback     // FIXME consider wrapped case     size_t tx_buf_sz = intf.txPI - intf.txCI;     void *src = reinterpret_cast<void *>(ivars->tx_buf + intf.txCI); //    char src[] = "Hello, World!";     void *dest = reinterpret_cast<void *>(ivars->rx_buf + intf.rxPI);     memcpy(dest, src, tx_buf_sz);     intf.rxPI += tx_buf_sz;     RxDataAvailable();     intf.txCI = intf.txPI;     TxFreeSpaceAvailable();     Log("[TX Buf]: %{public}s", reinterpret_cast<char *>(ivars->tx_buf));     Log("[RX Buf]: %{public}s", reinterpret_cast<char *>(ivars->rx_buf)); // dmesg confirms both buffers are all-zero     Log("[TX] txPI: %d, txCI: %d, rxPI: %d, rxCI: %d, txqoffset: %d, rxqoffset: %d, txlogsz: %d, rxlogsz: %d",         intf.txPI, intf.txCI, intf.rxPI, intf.rxCI, intf.txqoffset, intf.rxqoffset, intf.txqlogsz, intf.rxqlogsz); } void IMPL(VirtualSerialPortDriver, RxFreeSpaceAvailable) {     Log("RxFreeSpaceAvailable() called!"); } kern_return_t   IMPL(VirtualSerialPortDriver,HwResetFIFO){     Log("HwResetFIFO() called with tx: %d, rx: %d!", tx, rx);     kern_return_t ret = kIOReturnSuccess;     return ret; } kern_return_t   IMPL(VirtualSerialPortDriver,HwSendBreak){     Log("HwSendBreak() called!");     kern_return_t ret = kIOReturnSuccess;     return ret; } kern_return_t   IMPL(VirtualSerialPortDriver,HwProgramUART){     Log("HwProgramUART() called, BaudRate: %u, nD: %d, nS: %d, P: %d!", baudRate, nDataBits, nHalfStopBits, parity);     kern_return_t ret = kIOReturnSuccess;     return ret; }      kern_return_t   IMPL(VirtualSerialPortDriver,HwProgramBaudRate){     Log("HwProgramBaudRate() called, BaudRate = %d!", baudRate);     kern_return_t ret = kIOReturnSuccess;     return ret; } kern_return_t   IMPL(VirtualSerialPortDriver,HwProgramMCR){     Log("HwProgramMCR() called, DTR: %d, RTS: %d!", dtr, rts);     ivars->dtr = dtr;     ivars->rts = rts;     kern_return_t ret = kIOReturnSuccess; Exit:     return ret; } kern_return_t  IMPL(VirtualSerialPortDriver, HwGetModemStatus){     *cts = ivars->rts;     *dsr = ivars->dtr;     *ri = false;     *dcd = ivars->dtr;     Log("HwGetModemStatus() called, returning CTS=%d, DSR=%d, RI=%d, DCD=%d!", *cts, *dsr, *ri, *dcd);     kern_return_t ret = kIOReturnSuccess;     return ret; } kern_return_t   IMPL(VirtualSerialPortDriver,HwProgramLatencyTimer){     Log("HwProgramLatencyTimer() called!");     kern_return_t ret = kIOReturnSuccess;     return ret; } kern_return_t   IMPL(VirtualSerialPortDriver,HwProgramFlowControl){     Log("HwProgramFlowControl() called! arg: %u, xon: %d, xoff: %d", arg, xon, xoff);     kern_return_t ret = kIOReturnSuccess; Exit:     return ret; }
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2.1k
Feb ’25
Looking for USBSerialDriver sample code
I would like to write a driver that supports our custom USB-C connected device, which provides a serial port interface. USBSerialDriverKit looks like the solution I need. Unfortunately, without a decent sample, I'm not sure how to accomplish this. The DriverKit documentation does a good job of telling me what APIs exist but it is very light on semantic information and details about how to use all of these API elements. A function call with five unexplained parameters just is that useful to me. Does anyone have or know of a resource that can help me figure out how to get started?
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696
Feb ’25
IOUSBHostInterface::Open for interrupt interfaces works on iPad Air but not iPad Pro
I am trying to open the CommunicationControl class IOUSBHostInterface in my USB driver, but it only seems to open on iPad Airs and not iPad Pros. I'm calling ivars->interruptInterface->Open(this, 0, NULL); After retrieving the interruptInterface from the device's InterfaceIterator. I try and open this, but on iPad Pros it returns kIOReturnNotOpen. I've tried closing and reopening the IOUSBHostDevice, closing and reopening the Interface, AbortDeviceRequests before opening, etc. but it just seems to work on iPad Air and not iPad Pro. I've tried on both iPadOS 17.6.1 and 18.2 Has anyone else seen this?
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626
Dec ’24
How to get my extension’s process ID of the dext for debugging with lldb
I've asked this question in Stackoverflow, but no response, so I ask for help in here. I follow this guide Debugging and testing system extensions, and try to debug my dext code. In the Attach the debugger to your system extension, it said After your system extension launches, run the ps command-line tool and note your extension’s process ID. This is the current output for my dext status % systemextensionsctl list 1 extension(s) --- com.apple.system_extension.driver_extension enabled active teamID bundleID (version) name [state] * * K3TDMD9Y6B com.accusys.scsidriver (1.0/1) com.accusys.scsidriver [activated enabled] and I used the ps command but nothing happen, I can not get my extension’s process ID. ps aux | grep com.accusys.scsidriver or ps -ef | grep com.accusys.scsidriver How to do that? Any suggestion is appreciated.
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673
Dec ’24
Driver build does not get updated during Development
Hey, I'currently working on a Driver (and its App) for iPadOS (USB Device). I think have the right entitlements, as my driver gets installed with the app properly (after accepting it in the settings). It also gets loaded once the device is plugged in and so on. However the Kernel is not using the updated Version after I install a new Version of App and Driver to the iPad (at least most of the times). I'm verifying this by reading out the Logs via Console and the Driver prints its Build number on Start(). Sometimes it works like it should but I found no pattern. As far as I understand the iPad should automatically install the new Version of the Driver with the new App if its Build is different from the current one. I'm incrementing the Build of App and Driver automatically post-build so each build the iPad gets has its own Build number (This also works). Steps to reproduce: Cleaning Xcode Build Folder Unplugging the USB Device from the iPad. Building and Installing a new Version of the Driver and the App via Xcode (making sure the build number has changed) Plugging the USB back into the iPad Reading Console output of the iPad However it works (each time if I: Uninstall the app from the iPad manually or via Devices in Xcode Build and install the App via Xcode Open the Settings App and activate the Driver But uninstalling the App each time is taking a lot of time and manual Steps so I would like to fix this issue. Do you have any Ideas? Thanks, Bjarne
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679
Dec ’24
NSInternalInconsistencyException Call must be made on main thread
#4 Thread NSInternalInconsistencyException Call must be made on main thread CoreFoundation ___exceptionPreprocess + 164 libsystem_pthread.dylib _start_wqthread + 8 #0 Thread semaphore_wait_trap libsystem_kernel.dylib semaphore_wait_trap + 8 libdispatch.dylib 0x00000001b96ed000 + 457547470247841612 UnityFramework Staticburst_initialize + 17597401577822386088 UnityFramework DllCanUnloadNow + 52172 UnityFramework. DllCanUnloadNow + 51292 UnityFramework DllCanUnloadNow + 421068 UnityFramework. Unityplcrash_async_mach_exception_get_siginfo + 5073080 UnityFramework. GlobalizationNative_GetTimeZoneDisplayName + 1585284 UnityFramework. GlobalizationNative_GetTimeZoneDisplayName + 926212 UnityFramework. 0x000000010ce18000 + 77478852 UnityFramework. GlobalizationNative_GetTimeZoneDisplayName + 124804 UnityFramework. GlobalizationNative_GetTimeZoneDisplayName + 124592 UnityFramework. _ZdaPvRKSt9nothrow_t + 2445400 UnityFramework. _ZdaPvRKSt9nothrow_t + 2502608 UnityFramework. _ZdaPvRKSt9nothrow_t + 2556896 UnityFramework. _ZdaPvRKSt9nothrow_t + 2555820 UnityFramework. _ZdaPvRKSt9nothrow_t + 211836 UnityFramework. _ZdaPvRKSt9nothrow_t + 1216980 UnityFramework. _ZdaPvRKSt9nothrow_t + 1145620 UnityFramework. _ZdaPvRKSt9nothrow_t + 1145684 UnityFramework. _ZdaPvRKSt9nothrow_t + 1146408 UnityFramework. UnitySendMessage + 6940844 UnityFramework. _Z12DecodeBase64PKhPhi + 138076 QuartzCore. 0x00000001b2d06000 + 193228 UIKitCore. UIApplicationMain + 1589427071078105428 UnityFramework. _Z12DecodeBase64PKhPhi + 11056988545834161928
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571
Dec ’24