sonar(6x)							XScreenSaver manual							 sonar(6x)

NAME

       sonar - display a sonar scope

SYNOPSIS

       sonar  [-ping  hosts-or-subnets]  [-ping-timeout  int]  [-delay usecs] [-speed ratio] [-sweep-size ratio] [-font-size points] [-team-a-name
       string] [-team-b-name string] [-team-a-count int] [-team-b-count int] [-no-dns] [-no-times] [-no-wobble] [-debug] [-fps]

DESCRIPTION

       This draws a sonar screen that pings (get it?) the hosts on your local network, and plots their distance (response  time)  from	you.   The
       three rings represent ping times of approximately 2.5, 70 and 2,000 milliseconds respectively.

       Alternately, it can run a simulation that doesn't involve hosts.

OPTIONS

       sonar understands the following options:

       -ping hosts-or-subnets
	       The list of things to ping, separated by commas or spaces.  Elements of this list may be:

	       simulation  Run in simulation mode instead of pinging real hosts.

	       hostname    Ping the given host.

	       A.B.C.D	   Ping the given IP address.

	       subnet	   Ping the local class C subnet (the nearest 255 addresses).

	       subnet/NN   Ping a different-sized local subnet: e.g., subnet/28 would ping a 4-bit subnet (the nearest 15 addresses).

	       A.B.C.D/NN  Ping  an  arbitrary	other subnet.  The IP address specifies the base address, and the part after the slash is how wide
			   the subnet is.  Typical values are /24 (for 255 addresses) and /28 (for 15 addresses).

	       filename    Ping the hosts listed in the given file.  This file can be in the format used by /etc/hosts, or it can be any file that
			   has host names as the first or second element on each line.	If you use ssh, try this:

			     sonar -ping $HOME/.ssh/known_hosts

       -ping-timeout int
	       The amount of time in milliseconds the program will wait for an answer to a ping.

       -delay int
	       Delay between frames, in microseconds.  Default 20000.

       -speed ratio
	       Less than 1 for slower, greater than 1 for faster.  Default 1.

       -sweep-size ratio
	       How big the glowing sweep area should be. Default 0.3.

       -font-size points
	       How large the text should be.  Default 10 points.

       -no-wobble
	       Keep the display stationary instead of very slowly wobbling back and forth.

       -no-dns Do not attempt to resolve IP addresses to hostnames.

       -no-times
	       Do not display ping times beneath the host names.

       -team-a-name string
	       In simulation mode, the name of team A.

       -team-b-name string
	       In simulation mode, the name of team B.

       -team-a-count int
	       In simulation mode, the number of bogies on team A.

       -team-b-count int
	       In simulation mode, the number of bogies on team B.

       -fps    Display the current frame rate, polygon count, and CPU load.

NOTES

       On  most Unix systems, this program must be installed as setuid root in order to ping hosts.  This is because root privileges are needed to
       create an ICMP RAW socket.  Privileges are disavowed shortly after startup (just after connecting to the X server) so this is  believed	to
       be safe:
       chown root:root sonar
       chmod u+s sonar
       It  is  not  necessary  to  make  it  setuid on MacOS systems, because on MacOS, unprivileged programs can ping by using ICMP DGRAM sockets
       instead of ICMP RAW.

       In ping-mode, the display is a logarithmic scale, calibrated so that the three rings represent ping times  of  approximately  2.5,  70  and
       2,000 milliseconds respectively.

       This  means that if any the hosts you are pinging take longer than 2 seconds to respond, they won't show up; and if you are pinging several
       hosts with very fast response times, they will all appear close to the center of the screen (making their names hard to read.)

SEE ALSO

       X(1), xscreensaver(1), ping(8)

COPYRIGHT

       Copyright (C) 2000-2008 by Jamie Zawinski <jwz@jwz.org>
       Copyright (C) 1998 by Stephen Martin. <smartin@canada.com>

       Permission to use, copy, modify, distribute, and sell this software and its documentation for any purpose is hereby  granted  without  fee,
       provided that the above copyright notice appear in all copies and that both that copyright notice and this permission notice appear in sup-
       porting documentation.  No representations are made about the suitability of this software for any purpose.  It is provided "as is" without
       express or implied warranty.

AUTHORS

       Stephen Martin <smartin@canada.com>, 3-nov-1998.

       Subnet support, etc. added by Jamie Zawinski, 17-Jul-2000.

       Rewritten using OpenGL instead of X11 by Jamie Zawinski, 12-Aug-2008.

X Version 11							5.15 (28-Sep-2011)							 sonar(6x)