I'm using IOKit to connect to a custom USB HID device. I'm using XCode 14 and running Swift/SwiftUI. So far I have had great success reading from the device with IOHIDDeviceGetReport and this can be done repeatedly with no issues. However, when I use IOHIDDeviceSetReport, I can only successfully set the report to the device one time correctly but any subsequent call to this function would just end up with an I/O Timeout. Any calls using IOHIDDeviceGetReport still works fine so the USB Device is still functioning correctly, but I couldn't receive any additional IOHIDDeviceSetReport call. If I unplug the USB and plug it in again, I can once again successfully send a command. This is, of course, not very practical for the end user to have to unplug and plug the device in after a single set command, and I don't quite understand what's going on with this. Here's my SetOutputReport function to call the IOHIDDeviceSetReport. The IOHIDDevice must already be connected and opened before calling this function so it's not nil. I don't have this "one shot send command" problem on the PC (Windows 7, 10, 11) or Android (v.11,12,13,14) implementation of this Custom USB HID device. It seems like there's something at the lower level of IOHIDDeviceSetReport on macOS which might be done differently than what's available on the PC or Android. Many searches on the web yielded no useful results. There's an IOHIDDeviceSetReportWithCallback function and it also seems only to work one time as well. private func SetOutputReport(dev: IOHIDDevice? ,reportID: Int, data:[UInt8], reportLength: Int) -> String{ let inputReportID = reportID var buffer = data buffer[0] = UInt8(inputReportID) let bufferPointer = UnsafeMutablePointer<UInt8>.allocate(capacity: buffer.count) bufferPointer.initialize(from: &buffer, count: buffer.count) //print(bufferPointer[0]) let bufferLength: CFIndex = buffer.count var success: IOReturn = kIOReturnError if(dev != nil){ success = IOHIDDeviceSetReport(dev!, kIOHIDReportTypeOutput, CFIndex(buffer[0]), bufferPointer, bufferLength) } print("Set report result \(krToString(success))") return krToString(success) }

I'm working on a system management tool that should be able to Allow/Deny mass storage and portable devices. In case if it is a USB flash drive I can detect Mount events using Endpoint Security framework. Then using IOServiceGetMatchingServices I can find the actual device that is trying to mount new volume, check if it is an allowed device and Allow or Deny mount. But in case if it is an iPhone/iPad or Android device I can't rely on that solution as they don't mount new volumes but user can copy files to the phone. To cover this case I could respond with Deny for the ES_EVENT_TYPE_AUTH_IOKIT_OPEN event. But at that moment I know nothing about the device, only its class which is the same for a mouse and for iPhone. I can add a notification for adding new USB devices, but then I would need somehow to understand that it is a phone/tablet and disconnect or suspend needed USB Device. How could I disconnect or suspend a USB Device having only io_object_t?

I have developed a kernel extension (KEXT) for driving SCSI devices and I am able to successfully use it to send commands to the underlying device. The driver class overrides the newUserClient method which gets called whenever IOServiceOpen is called from the user space so that apps can make use of the driver. Is there any way to restrict access to this kernel extension such that only my app would be able to open a user client to access the driver and communicate with it using IOConnectCallMethod?

Hi, I am developping an app for IOS using React Native. I want to write a native modules in Swift and use Objective C to bridge the React Native JS functions with native component. In particular, i want to use IOKit framework to access such information as Battery Temperature and Battery Level. I read in many stackoverflow articles and in ChatGPT that the usage of IOS Private APIs are forbidden andd Apple will reject the app from AppStore and block the account. Is it true? Is there any legal way to use low level APIs and avoid to be rejected or blocked by Apple? The official Apple Technical Support is not responding me. I would really appreciate your help and support. Best Regards, Kamran

Hi. I have a class-compliant usb device which announces its serial number as m4121095, as per its kUSBSerialNumberString property. However, the file name it is provided is tty.usbmodemm41210951 – it's the serial number with an additional 1 at the end. What is the meaning of this appendage? (I'm tempted to believe that the 1 at the end is there in the unlikely case another device with the same SN is connected, but there's no way to test this possibility). In the end, I would like to obtain a filename that is guaranteed to be representing a connection to exactly this device. Can I assume that the filename of a device that follows the same protocol of serial numbering will be consistently appended with a number that can in some way be inferred? Thank you.