On Fri, Jul 10, 2020 at 06:59:45PM +0530, Kanchan Joshi wrote:

quoted

block doesn't work for the case of writes to files that don't have
to be aligned in any way.  And that I think is the more broadly
applicable use case than zone append on block devices.

But when can it happen that we do zone-append on a file (zonefs I
asssume), and device returns a location (write-pointer essentially)
which is not in multiple of 512b?

All the time.  You open a file with O_APPEND.  You write a record to
it of any kind of size, then the next write will return the position
it got written at, which can be anything.