when ufs is 99% full, current seems to limit creat to 28672 bytes

[Gary Palmer]

On Thu, Dec 29, 2016 at 09:39:16PM +0100, Julian H. Stacey wrote:
> It was really a temporary cludge of mine to tickle for bad blocks,
> working from inside the file system. I'd better do it properly,
> unmount & experiment with eg camcontrol on the partition or whole
> disk, or search ports/ &/or write  a little C prog that reads blocks
> from a file (aka dev name of partition or whole disk, stores, to
> memory, & writes back blocks)

You may want to try recoverdisk(1).  I'm not sure, I've never used
it to read and write to the same device

Regards,

Gary