@item -s, --snapshot
use snapshot file
@item -n, --nocache
- disable host cache
+@itemx --cache=@var{cache}
+ set cache mode to be used with the file. See the documentation of
+ the emulator's @code{-drive cache=...} option for allowed values.
+@item --aio=@var{aio}
+ choose asynchronous I/O mode between @samp{threads} (the default)
+ and @samp{native} (Linux only).
+@item --discard=@var{discard}
+ toggles whether @dfn{discard} (also known as @dfn{trim} or @dfn{unmap})
+ requests are ignored or passed to the filesystem. The default is no
+ (@samp{--discard=ignore}).
@item -c, --connect=@var{dev}
connect @var{filename} to NBD device @var{dev}
@item -d, --disconnect
disconnect the specified device
@item -e, --shared=@var{num}
device can be shared by @var{num} clients (default @samp{1})
+@item -f, --format=@var{fmt}
+ force block driver for format @var{fmt} instead of auto-detecting
@item -t, --persistent
don't exit on the last connection
@item -v, --verbose