beep

BEEP(1)                     General Commands Manual                    BEEP(1)



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)