Bell & ssh

[Edward]

James Wilkinson wrote:

> Bill Gradwohl wrote:
> 
>>I want the remote box to beep. I want to understand where the difference 
>>is since the echo command executes on the remote machine regardless. How 
>>does ssh turn the bell off?
> 
> 
> It doesn't. It doesn't turn it *on*.
> 
> There are a couple of issues to think about.
> 
> One is that normally a shell script will send a beep to the controlling
> terminal. Normally, if you have a remote terminal, be it SSH or telnet
> or a serial connection, the beep signal will be sent as ASCII 7 to the
> terminal in question, since the beep is designed to attract the user's
> attention.
> 
> Think about a single Unix box in a server room somewhere, with hundreds
> of logged-on user sessions over several warehouses, possibly in multiple
> countries. A beep would be generated by a process connected to *one*
> session, and you'd want that user to hear the beep.
> 
> (I've actually just described my workplace, incidentally).
> 
> So a beep will be sent as ASCII to the controlling terminal. If you're
> logged on locally, then there will be support for the speaker as part of
> the terminal emulation.
> 
> The other is who owns /dev/console? Under Fedora, this will change
> depending on who is logged in there. So if you give permission for a
> different user to sound a beep, then Fedora is likely to change those
> permissions under you.
> 
> Take a look at /etc/security/console.perms to see what you might want to
> change. And look at
> http://www.redhat.com/docs/manuals/linux/RHL-9-Manual/custom-guide/s1-access-console-files.html
> 
> As for getting the right beeper to beep ... I'm not sure. If necessary,
> you could try playing around with
> http://www.geocities.com/stssppnn/pcsp.html or another PC Speaker
> driver...
> 
> (I must admit, I can't help you much more, as this box has the beep
> firmly turned OFF, and I haven't compiled the driver for this kernel...)
> 
> James.

I haven't been following this thread, but a thought just occurred to me. 
If it's been covered, my apologies.

Could you run a command to check on which tty or whatever the user is 
logged in and as root echo a bell character directly to the relevant 
/dev entry? Would that work?

Regards,
Ed.