How can I fix Error: -69877: Couldn't open device after interrupted formatting process? This question, possibly the same question, has been asked: Couldn&#39;t open device

However, my question hopefully demonstrates a more specific scenario as the situation in which caused the error explicitly known:

The following done as a root user:


I plugged in my SD card and ran diskutil list to grab the internal device node (/dev/disk2)
I ran diskutil partitionDisk /dev/disk2 GPT UFSD_EXTFS4 New 100% (UFSD_EXTFS4 is ext4 provided by Paragon)
I saw that it was working, so I interrupted the process at step 2.
I attempted to rerun the command with the number of partitions explicitly stated diskutil partitionDisk /dev/disk2 1 GPT UFSD_EXTFS4 New 100%


I get the message: 

Started partitioning on disk2
Unmounting disk
Error: -69877: Couldn't open device


Running gpt show -l /dev/disk2 yields

start     size  index  contents
    0  7741440


Running gpt destroy /dev/disk2 yields

gpt destroy: unable to open device '/dev/disk2': Permission denied


It seems to me there is some lock on device disk2. I just need to figure out how to release it.

I was able to release it by rebooting into safe mode (holding shift key during boot) and then rebooting back into normal mode. I would like to know, however, what exactly could be done to release this lock without rebooting.
For anyone else who ends up on this question after searching online, be sure that you confirm that your SD card is not mounted as read-only! There is a physical tab that you may need to move: