1、The hardware is usb token，it uses the USB Mass Storage protocol.
2、The system update to 15.3 causes the problem.
3、Using the IOUSBInterface is to send command to the device.IOUSBInterface is used by libusb.
4、We have not tried using the IOUSBHost framework.There is very little information how to use it.
5、The failure occurs all the time when accessing the usb token.
I think this is caused by the system upgrade, which leads to the control of the deamon program's access to USB devices.
aibuwan2008
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