USBInterfaceOpen Fails to Open: Troubleshooting USB Communication with IOKit and Objective-C in macOS Environment

If you encounter problems when using IOUSBInterfaceOpen to open a USB interface, there could be several reasons:

• Permission issues: The application may not have sufficient permissions to access the USB device. Ensure that the application has the correct permissions. In some cases, you may need to run the application with root privileges.

• Device occupied by another application: If the device is already opened and in use by another application, your application will not be able to open the interface. Make sure no other applications are using the USB device.

• Hardware issues: There could be hardware issues causing the USB device to malfunction. Try using a different USB port or replacing the USB device to rule out hardware issues.

• Driver issues: There could be driver-related issues with the USB device. Make sure your system has the correct drivers and they are up-to-date.

• Incorrect interface parameters: Ensure that the interface number and other parameters you are using are correct. Check the technical documentation of the USB device to ensure you are using the correct values.

To resolve this issue, you can try the following methods:

• Run your application with root privileges.

• Make sure all USB connections and devices are functioning properly.

• Check the USB interface parameters used in your application and adjust them according to the device’s technical documentation.

• Close other applications that may be using the same USB device.