is a disk image filename
port to listen on (default B<1024>)
offset into the image
interface to bind to (default B<0.0.0.0>)
Use a unix socket with path I<path>
export read-only
only expose partition I<num>
use snapshot file
disable host cache
connect FILE to NBD device DEV
disconnect the specified device
device can be shared by I<num> clients (default B<1>)
don't exit on the last connection
display extra debugging information
display this help and exit
output version information and exit