Provided by: beep_1.3-4+deb9u1~build0.16.04.1_amd64 
NAME
beep - beep the pc speaker any number of ways
SYNOPSIS
beep [--verbose | --debug] [-e device | --device device] [-f N] [-l N] [-r N] [-d N] [-D N] [-s] [-c]
beep [ OPTIONS ] [-n] [--new] [ OPTIONS ]
beep [-h] [--help]
beep [-v] [-V] [--version]
DESCRIPTION
beep allows the user to control the pc-speaker with precision, allowing different sounds to indicate
different events. While it can be run quite happily on the command line, it's intended place of
residence is within shell/perl scripts, notifying the user when something interesting occurs. Of course,
it has no notion of what's interesting, but it's real good at that notifying part.
All options have default values, meaning that just typing 'beep' will work. If an option is specified
more than once on the command line, subsequent options override their predecessors. So 'beep -f 200 -f
300' will beep at 300Hz.
OPTIONS
--verbose, --debug
enable debug output. This option prints a line like the following before each beep:
[DEBUG] 5 times 200 ms beeps (100 delay between, 0 delay after) @ 1000.00 Hz
-e device, --device device
use device as event device. If the switch isn't used, /dev/tty0 and /dev/vc/0 are tried in turn.
-f N beep at N Hz, where 0 < N < 20000. As a general ballpark, the regular terminal beep is around
750Hz. N is not, incidentally, restricted to whole numbers.
-l N beep for N milliseconds.
-r N specify the number of repetitions (defaults to 1).
-d N, -D N
specify a delay of N milliseconds between repetitions. Use of -d specifies that this delay should
only occur between beeps, that is, it should not occur after the last repetition. -D indicates
that the delay should occur after every repetition, including the last. Normally, -d is what you
want, but if, for example, you are stringing several beep commands together to play the star wars
anthem, you may want control over every delay.
-n, --new
this option allows you to break the command line up into specifying multiple beeps. Each time
this option is used, beep starts treating all further arguments as though they were for a new
beep. So for example:
beep -f 1000 -n -f 2000 -n -f 1500
would produce a sequence of three beeps, the first with a frequency of 1000Hz (and otherwise
default values), then a second beep with a frequency of 2000Hz (again, with things like delay and
reps being set to their defaults), then a third beep, at 1500Hz. This is different from
specifying a -r value, since -r repeats the same beep multiple times, whereas -n allows you to
specify different beeps. After a -n, the new beep is created with all the default values, and any
of these can be specified without altering values for preceding (or later) beeps. See the
EXAMPLES section if this managed to confuse you.
-s, -c these options put beep into input-processing mode. -s tells beep to read from stdin, and beep
after each newline, and -c tells it to do so after every character. In both cases, the program
will also echo the input back out to stdout, which makes it easy to slip beep into a text-
processing pipeline, see the EXAMPLES section.
-h, --help
display usage info and exit
-v, -V, --version
display version information and exit
EXAMPLES
At its simplest (yet still effective)
beep
A more interesting standalone setup
beep -f 300.7 -r 2 -d 100 -l 400
As part of a log-watching pipeline
tail -f /var/log/xferlog | grep --line-buffered passwd | \
beep -f 1000 -r 5 -s
When using -c mode, I recommend using a short -D, and a shorter -l, so that the beeps don't blur
together. Something like this will get you a cheesy 1970's style beep-as-you-type-each-letter effect
cat file | beep -c -f 400 -D 50 -l 10
A highly contrived example of -n/--new usage
beep -f 1000 -r 2 -n -r 5 -l 10 --new
will produce first two 1000Hz beeps, then 5 beeps at the default tone, but only 10ms long each,
followed by a third beep using all the default settings (since none are specified).
IOCTL WACKINESS
Some users will encounter a situation where beep dies with a complaint from ioctl(). The reason for
this, as Peter Tirsek was nice enough to point out to me, stems from how the kernel handles beep's
attempt to poke at (for non-programmers: ioctl is a sort of catch-all function that lets you poke at
things that have no other predefined poking-at mechanism) the tty, which is how it beeps. The short
story is, the kernel checks that either:
- you are the superuser
- you own the current tty
What this means is that root can always make beep work (to the best of my knowledge!), and that any local
user can make beep work, BUT a non-root remote user cannot use beep in it's natural state. What's worse,
an xterm, or other x-session counts, as far as the kernel is concerned, as 'remote', so beep won't work
from a non-privileged xterm either. I had originally chalked this up to a bug, but there's actually
nothing I can do about it, and it really is a Good Thing that the kernel does things this way. There is
also a solution.
By default beep is not installed with the suid bit set, because that would just be zany. On the other
hand, if you do make it suid root, all your problems with beep bailing on ioctl calls will magically
vanish, which is pleasant, and the only reason not to is that any suid program is a potential security
hole. Conveniently, beep is very short, so auditing it is pretty straightforward.
Decide for yourself, of course, but it looks safe to me - there's only one buffer and fgets doesn't let
it overflow, there's only one file opening, and while there is a potential race condition there, it's
with /dev/console. If someone can exploit this race by replacing /dev/console, you've got bigger
problems. :)
So the quick, only, and likely safe solution if beep is not beeping when you want it to is (as root):
# chmod 4755 /usr/bin/beep
(or wherever you put it)
The one snag is that this will give any little nitwit the ability to run beep successfully - make sure
this is what you want. If it isn't, a slightly more complex fix would be something like:
# chgrp beep /usr/bin/beep
# chmod 4750 /usr/bin/beep
and then add only beep-worthy users to the 'beep' group.
FREQUENCY TABLE
Several people have asked for some basic help translating music notes to frequencies. There are a lot of
music notes, and several tables online will give you translations, but here are approximate numbers for
the octave of middle C, to get you started.
Note Frequency
C 261.6
C# 277.2
D 293.7
D# 311.1
E 329.6
F 349.2
F# 370.0
G 392.0
G# 415.3
A 440.0
A# 466.2
B 493.9
C 523.2
BUGS
None that I'm aware of, though see the IOCTL WACKINESS section.
REPORTING BUGS
Report bugs to <johnath@johnath.com>
AUTHOR
This program was written by Johnathan Nightingale (johnath@johnath.com) and is distributed under the GNU
General Public License. For more contributing information, check the source, and past contributors can
be found in CREDITS.
July 2008 BEEP(1)