[CentOS] mkfs.fat Device or resource busy

Sun May 24 23:33:25 UTC 2020
Michael Hennebry <hennebry at web.cs.ndsu.nodak.edu>

I'm trying to format a 16 GB SD card to FAT32.
Either it won't find the device or it
gives me the titular error message.

mkfs.fat /dev/sdc

I have tried "ejecting" the drive and reinserting the card.
I have tried inserting another card, checking to insure
that I could see its file, ejecting that card and
inserting the target card.
If I do not umount it, busy, if I don't, not found.

What is the incantation for formatting an SD card.

BTW I am using Centos 7 and a USB adapter.

Michael   hennebry at web.cs.ndsu.NoDak.edu
"Sorry but your password must contain an uppercase letter, a number,
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