Use dd to continue wiping drive from where it last failed

Question

I have a 200GB HDD that I was using dd to zero-write overnight. I woke up to the following output:

$ dd if=/dev/zero of=/dev/sdc bs=4M status=progress
203901894656 bytes (204 GB, 190 GiB) copied, 7283.07 s, 28.0 MB/s
dd: error writing '/dev/sdc': Permission denied
48621+0 records in
48620+0 records out
208223076351 bytes (208 GB, 194 GiB) copied, 8379.27 s, 24.8 MB/s

As far as I'm able to read the output, dd seems to have written most data to the drive, but the Permission denied error worries me that the last part of the drive hasn't been wiped. I'm guessing the error was caused by the drive unmounting itself, even though this has never happened before.

I want to make sure that the last part of the drive is clean. How would I go about doing this?

I've already come across this similar question, but my understanding of both bash and the maths required are too inadequate for me to understand how to adapt the answer for what I want to do.

Please also note that I'm on Cygwin, where the blockdev package isn't available for download.

Answer 1

You've already written 48620 blocks, so...

dd ... seek=48620