RADIO(1) RADIO(1)
NAME
radio - receive audio UDP packets transmitted by broadcast
SYNOPSIS
radio [ -c port ] [ -d ] [ -f ] [ -l addr ] [ -m mcastgrp ]
[ -n ] [ -p port ] [ -r addr ] [ -s ] [ -t ] [ -v volume ]
DESCRIPTION
Radio allows you to listen to audio transmitted as UDP packets on a
local area network by broadcast(1). Obviously, this requires a
workstation with audio hardware; currently the program works on SGI
Indigo and 4D/35 workstations, Sun Sparcs, all NeXTs, DECStations
equipped with DEC LoFi, and any machine running the Audio File server
from DEC CRL.
Radio is normally run in the background. You may need a system-
specific tool to change the volume or direct the output to the speaker
or headphone jack; e.g., on an SGI, you would use apanel(1);
on a Sun you would use gaintool(1) or, when using X, x_gaintool(1)
(these programs can be found in /usr/demo/SOUND in SunOS 4.1). With
OpenWindows 3.0, you can use audiotool(1). (On the NeXT, just use the
volume keys on the keyboard.)
Some loss of UDP packets is tolerated; this is heard as short
interruptions of the sound.
OPTIONS
-c port Use this UDP port number as control port (default 54320).
Normally you never need to change this; the control port is
used by optional ``tuner'' software (not distributed) and
possibly by listener polling programs.
-d Turn on debugging (a message on stderr for each 8 packets
received, and when rare or unexpected events happen).
-f Filter mode: write the U-LAW audio data to stdout instead of
sending it to the audio hardware.
-l addr Listen only for packets to IP address addr (useful for
forwarding stations).
-m mcastgrp
Multicast group. This only makes sense if the same
multicast group is passed as address to broadcast(1). Using
multicasting instead of broadcasting reduces the load on
machines that aren't listening. You should use the same
multicast group for all stations on the local network.
(Note that even if a multicast group is specified, stations
using broadcasts can still be picked up by radio).
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RADIO(1) RADIO(1)
-n Noninterruptable mode (Sun Sparc only). By default, radio
notices when another program wants to open the audio output
device, and temporarily ``backs off'' until the other
program is finished, hoping it won't take too long. This
option turns off that feature.
-p port Receive packets sent to this UDP port number (default
54321). This corresponds to the port used by broadcast.
Port numbers 1..99 are shorthands for 54321..54419.
-r addr Listen only for packets from IP address addr (useful for
forwarding stations).
-s Secure mode: don't listen to the control port. This is for
really paranoid users: in theory, any user on the net can
override the port specified with -p by sending a control
message to the control port of your radio program.
-t Tee mode: write the U-LAW audio data to stdout as well as
sending it to the audio hardware.
-v volume Set the initial volume, on a scale from 0 to 100. (SGI and
Sun Sparc only.) By default, the volume is left unchanged.
When the volume is specified this way, its original value is
restored when the program exits.
AUTHOR
Guido van Rossum
VERSION
This manual page documents radio version 2.0, patchlevel 3.
SEE ALSO
broadcast(1), tuner(1), ektuner(1)
COPYRIGHT
Copyright 1991, 1992, 1993 by Stichting Mathematisch Centrum,
Amsterdam, The Netherlands.
All Rights Reserved
Permission to use, copy, modify, and distribute this software and its
documentation for any purpose and without fee is hereby granted,
provided that the above copyright notice appear in all copies and that
both that copyright notice and this permission notice appear in
supporting documentation, and that the names of Stichting Mathematisch
Centrum or CWI not be used in advertising or publicity pertaining to
distribution of the software without specific, written prior
permission.
STICHTING MATHEMATISCH CENTRUM DISCLAIMS ALL WARRANTIES WITH REGARD TO
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RADIO(1) RADIO(1)
THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
FITNESS, IN NO EVENT SHALL STICHTING MATHEMATISCH CENTRUM BE LIABLE
FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
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