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beep is a command line tool for linux that beeps the PC speaker
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johnath/beep
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Intro ----- I just got so tired of being limited to printf("\a"); when I wanted a terminal beep. This program isn't supposed to be anything stupendous, it's just supposed to get the job done. Its intended purpose in life is to live inside shell/perl scripts, and allow a little more granularity than you get with the default terminal bell. Maybe I'm the only one who thinks this is useful. :) If for any reason you decide you need to, contact me: [email protected] http:https://johnath.com/ And beep can generally be found at: http:https://johnath.com/beep/ For installation instructions, see INSTALL. For copying and (non-)warranty information, see COPYING. For usage information, check the man page. There is a github repository of this code at: git:https://github.com/johnath/beep.git A note about ioctl ------------------ As noted in the man page, some users are running into 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-priviledged 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 solution is beep is not beeping when you want it to is: $ su Password: # 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. Playing Songs ------------- A surprising number of people have sent in requests, or even patches, to help beep play multiple, different sounds off a single invocation. I had always thought that if people wanted a more complex melody, they would just do something like: $ cat << EOF > song.sh #!/bin/sh beep <first beep's options> beep <second beep's options> etc... EOF Nevertheless, because of repeated and vociferous demand, version 1.2 (and presumably all later versions) include the -n/--new switch which allows you to use one command line to create multiple beeps. Check the man page for details. I have also had a couple people suggest that I encourage the development of such shell scripts/command lines, even collect the particularly melodious ones. Certainly if anyone feels like sending some to me, I will put them somewhere visible, or even include them as a sample. I think Dvorak's New World Symphony, 4th Movement, for example, would make a lovely shell script. I also wouldn't mind a rendition of BNL's If I had a million dollars. But by all means, be creative. All files copyright (C) Johnathan Nightingale, 2002. All files distributed under the GNU general public license.
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