.TP
.B unit \fInum
Sets the ppp unit number (for a ppp0 or ppp1 etc interface name) for outbound
-connections.
+connections. If the unit is already in use a dynamically allocated number will
+be used.
+.TP
+.B ifname \fIstring
+Set the ppp interface name for outbound connections. If the interface name is
+already in use, or if the name cannot be used for any other reason, pppd will
+terminate.
.TP
.B unset \fIname
Remove a variable from the environment variable for scripts that are