On Thu, Jun 6, 2019 at 9:49 AM Richard Ryniker <ryniker@xxxxxxxxxxxx> wrote: > > I think you will find the file is not truly empty. /sys is not an actual > file system, merely an interface to kernel information. There is no > directory structure that records the length or other attributes of a file, > as is the case for data on real media such as disks. > > If you read the /sys/kernel/debug/usb/devices file, you should find the > data you seek. [root@fmac ~]# ls -l /sys/kernel/debug/usb/devices -r--r--r--. 1 root root 0 Jun 6 10:11 /sys/kernel/debug/usb/devices [root@fmac ~]# cat /sys/kernel/debug/usb/devices cat: /sys/kernel/debug/usb/devices: Operation not permitted [root@fmac ~]# 5.2.0-0.rc3.git1.1.fc31.x86_64 -- Chris Murphy _______________________________________________ test mailing list -- test@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe send an email to test-leave@xxxxxxxxxxxxxxxxxxxxxxx Fedora Code of Conduct: https://getfedora.org/code-of-conduct.html List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/test@xxxxxxxxxxxxxxxxxxxxxxx