[question] What happens when dd writes data to a missing device?

[Mikhail Gavrilov]

Hi folks!
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?


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Best Regards,
Mike Gavrilov.