.IP "\fBssl:\fIip\fB:\fIport\fR"
The specified SSL \fIport\fR on the host at the given \fIip\fR, which
must be expressed as an IP address (not a DNS name) in IPv4 or IPv6 address
format.  If \fIip\fR is an IPv6 address, then wrap \fIip\fR with square
brackets, e.g.: \fBssl:[::1]:6640\fR.
The \fB\-\-private\-key\fR, \fB\-\-certificate\fR, and \fB\-\-ca\-cert\fR
options are mandatory when this form is used.
.
.IP "\fBtcp:\fIip\fB:\fIport\fR"
Connect to the given TCP \fIport\fR on \fIip\fR, where \fIip\fR can be IPv4
or IPv6 address. If \fIip\fR is an IPv6 address, then wrap \fIip\fR with
square brackets, e.g.: \fBtcp:[::1]:6640\fR.
.
.IP "\fBunix:\fIfile\fR"
On POSIX, connect to the Unix domain server socket named \fIfile\fR.
.IP
On Windows, connect to a localhost TCP port whose value is written in
\fIfile\fR.