How to delete all partitions for a complete reinstall

[Gary W. Swearingen]

Alexander Skwar <listen at alexander.skwar.name> writes:

> With Erics command, a "huge" number of write requests is sent (512,
> to be exact). And every time, just 1 byte is written. That's tremendously
> slow!

I'm not so sure.  It's my dim understanding that the disk interfaces
(and so drivers) can write only in increments of a 512-byte sector.
(It shouldn't be hard to test, but I'm not in the mood.)  Unsure if
"dd" complains or pads or what.  But I very much doubt if it reads,
changes a byte, and writes back.