playing short tune via beep

[John Heim]

----- Original Message ----- 
From: "Andor Demarteau" <andor at nl.linux.org>
To: "Linux for blind general discussion" <blinux-list at redhat.com>
Sent: Tuesday, March 11, 2008 3:11 PM
Subject: Re: playing short tune via beep


> On Tue, 11 Mar 2008, Geoff Shang wrote:
>
> > Andor Demarteau wrote:
> >
> > > a central C is 440hz so you could calculate the rest and play a trye
> > > melodie like you could do in gwbasic zo long ago :)
> >
> > 440Hz is A, not C.  It is the A above middle C on a piano.
> ofcourse, how stupid of me :(


Wow... It's amazing how long this thread has survived. Every few weeks, it 
comes back.
I was hoping somebody would already have some tunes they'd written with 
beep. But I eventually put together some tunes by just experimenting with 
parameters. And it works really well, In fact, my beep-alarm on my computer 
at home went off at 3:00 AM this morning. I had configured my linux box at 
home to trigger an alarm if it couldn't get status info from the apache 
server at work. As it turned out, it was just that my ISP had changed my IP 
address in the middle of the night and the status page on the apache server 
is restricted by IP. When the apache server rejected the request for status 
info because it came from an unrecognized IP, that triggered the alarm.

It was kind of a pain but I was gratified to know the system is working. 
The tunes I wrote are supposed to sound like bird songs. The first 3 notes 
of a robin song "cheer-e-o" signals trouble. The first 2 notes of a cardinal 
song, "right here!", signals a recovery. And the 4 notes of a white throated 
sparrow, "oh canada", mean unknown error.

The status checks are done via a package called nagios. I wrote a plug-in 
for nagios to download the  server-status document from an apache server and 
parse it. So with this plug-in, you can configure nagios to trigger an alarm 
if the number of apache sub-processes goes over some limit. This could 
indicate that the server is close to being over loaded. Of course, the alarm 
would also go off if it can't get the status info at all.

Nagios is really cool though. I will have to configure it so it doesn't 
check between 11 PM and 6 AM. There is nothing I can do if there is a 
problem during those hours anyway.