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Doesn't pv give you an ETA if the output device size is known?

I recently did

pv </dev/zero >/dev/sdb

to zero a drive and I'm pretty sure it gave me an ETA...

You have to supply the input device (or file) as an argument, instead of using stdin. Then it will read the size of the device/file.

As far as I know, this does not work for the output device, and the size must be specified.

So:

pv /path/file >/dev/device

Will give you an ETA.

On Linux, pv can actually determine the size of the output device (using lseek on stdout), so `pv </dev/zero >/dev/sdb` does give a correct ETA (tested with pv 1.6.6 on Debian).

That seems to be exactly why it's endorsed.

> For larger disks, an ETA proves invaluable. I like pv for this task.

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