On Mon, 12 Oct 2020, Mikhail Gavrilov wrote: > I have a question. > What happens when dd writes data to a missing device? > > For example: > # dd > if=/home/mikhail/Downloads/Fedora-Workstation-Live-x86_64-Rawhide-20201010.n.0.iso > of=/dev/adb > > Today I and wrongly entered /dev/adb instead of /dev/sdb, > and what my surprise was when the data began to be written to the > /dev/adb device without errors. > > But my surprise was even greater when cat /dev/adb started to display > the written data. > > I have a question: > Where the data was written and could it damage the stored data in > memory or on disk?
If the device node /dev/adb does not exist (most likely udev case when you don't have the device/no module loaded for it) then dd as root will just create a normal file inside the /dev ramdisk. Only if the device node exists but is not handled then something else like an open error will happen. c'ya sven-haegar -- Three may keep a secret, if two of them are dead. - Ben F.
