During 'qemu-img create ... 2>&1', if --quiet is not in force, we can
end up with buffered I/O in stdout that was produced before failure,
but which appears in output after failure. This is confusing; the fix
is to flush stdout prior to attempting anything that might produce an
error message. Several iotests demonstrate the resulting ordering
change now that the merged outputs now reflect chronology. (An even
better fix would be to avoid printf from within block.c altogether,
but that's much more invasive...)
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20200706203954.341758-2-eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20200122164532.178040-6-mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
[mreitz: Added a note that NBD does not support resizing, which is why
the second case is expected to fail]
Signed-off-by: Max Reitz <mreitz@redhat.com>
