Paul Bijnens's Mail:
> Is the shell command "mt -f ... rewind" returning immediatly too?
> If yes, and you issue another command, does it give an error then?
> Does the "mt -f ... status" giving an error, or does it indicate
> that the rewind is still in progress?
With the command sequence

        export TAPE=...
        mt rewind; echo rewind done; tar cv ...

I see the ``rewind done'' almost immediately, while it takes quite a while
before I see the output from tar, which successfully writes to tape.

But the fundamental difference to the situation within amtapetype is, that
with shell commands, the tape device is closed after the rewind and
re-opened (by another process) for writing data.

If I insert a ``mt status'' just before the tar, a significant delay is
between the ``rewind done'' and the status output (which reports beginning
of media), and tar output starts immediately after the status output.

Seems that the re-open operation forms a sort of synchronization point.

Bye

        \franz