Yes, I know that addressing a nibble (4 bits) to a byte is not possible unless you have a 4-bit computer like the Intel 4004, Toshiba TLCS-47 etc. That's the whole reason why you, to get that effect, have to read-modify-write the whole byte.
It is actually kind of the same as how you must read-modify-write a whole sector to change one byte on a disk.
Also, and perhaps more importantly; I was only joking/trolling and I have no idea why anyone would want to describe my post as Informative. Perhaps they found "Most modern drives are much larger than 4 bits." to be informative?
The problem with writing 1010 all over the disk is that it only covers an extremely tiny fraction of the disk. Most modern drives are much larger than 4 bits.
It is also highly inefficient since the OS would always have to read a whole sector (typically 512 bytes) and modify it in memory before writing it back again to avoid changing any bits outside of those 4 that are to be wiped!
So, why not just sell it on eBay and hope the buyer wipes the disk before using it?
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