S<[ B<-b> capture ring buffer option ] ...>
S<[ B<-B> capture buffer size (Win32 only) ] >
S<[ B<-c> capture packet count ]>
+S<[ B<-D> ]>
S<[ B<-f> capture filter ]>
S<[ B<-g> packet number ]>
S<[ B<-h> ]>
Set the maximum number of packets to read when capturing live
data.
+=item -D
+
+Print a list of the interfaces on which B<Ethereal> can capture, and
+exit. For each network interface, a number and an
+interface name, possibly followed by a text description of the
+interface, is printed. The interface name or the number can be supplied
+to the B<-i> flag to specify an interface on which to capture.
+
+This can be useful on systems that don't have a command to list them
+(e.g., Windows systems, or UNIX systems lacking B<ifconfig -a>);
+the number can be useful on Windows 2000 and later systems, where the
+interface name is a somewhat complex string.
+
+Note that "can capture" means that B<Ethereal> was able to open
+that device to do a live capture; if, on your system, a program doing a
+network capture must be run from an account with special privileges (for
+example, as root), then, if B<Ethereal> is run with the B<-D> flag and
+is not run from such an account, it will not list any interfaces.
+
=item -f
Set the capture filter expression.
=item -i
Set the name of the network interface or pipe to use for live packet
-capture.
+capture.
Network interface names should match one of the names listed in
-"B<tethereal -D>". If you're using Unix, "B<netstat -i>" or "B<ifconfig
--a>" might also work to list interface names, although not all versions
-of Unix support the B<-a> flag to B<ifconfig>.
+"B<ethereal -D>" (described above); a number, as reported by
+"B<ethereal -D>", can also be used. If you're using UNIX, "B<netstat
+-i>" or "B<ifconfig -a>" might also work to list interface names,
+although not all versions of UNIX support the B<-a> flag to B<ifconfig>.
+
+If no interface is specified, B<Ethereal> searches the list of
+interfaces, choosing the first non-loopback interface if there are any
+non-loopback interfaces, and choosing the first loopback interface if
+there are no non-loopback interfaces; if there are no interfaces,
+B<Ethereal> reports an error and doesn't start the capture.
Pipe names should be either the name of a FIFO (named pipe) or ``-'' to
read data from the standard input. Data read from pipes must be in