-4 (IPv4 only)
Force the use of IPv4 only.
-6 (IPv6 only)
Force the use of IPv6 only.
-U, --unixsock (Use Unix domain sockets)
Use Unix domain sockets rather than network sockets. This
option may be used on its own for stream sockets, or combined
with --udp for datagram sockets. A description of -U mode is
in the section called 'UNIX DOMAIN SOCKETS'.
-u, --udp (Use UDP)
Use UDP for the connection (the default is TCP).
--sctp (Use SCTP)
Use SCTP for the connection (the default is TCP). SCTP
support is implemented in TCP-compatible mode.
--vsock (Use AF_VSOCK sockets)
Use AF_VSOCK sockets rather than the default TCP sockets
(Linux only). This option may be used on its own for stream
sockets or combined with --udp for datagram sockets. A
description of --vsock mode is in the section called
'AF_VSOCK SOCKETS'.
