Re: Script to check whether modem telephone line in use --- how?

[Mark Phillips <mark@ist.flinders.edu.au>]

> On Wed, Mar 31, 1999 at 11:41:47PM -0600, Bud Rogers wrote:
> > Mark Phillips <mark@ist.flinders.edu.au> writes:
> > 
> > > I hope this explains now why I was trying to write a script that would
> > > actually allow me to hear what was on the phoneline, enabling me to
> > > determine if my father was actually using it.  (At the moment the only
> > > way is to physically go upstairs and check his computer/ask him.)
> > 
> > Put ABORT "NO DIALTONE" in your ppp chat script.
> 
> In my experience, the noise of the line being picked and up dropped
> by the other modem will interfere with the session -- it will almost
> certainly cause the modems to retrain, and may cause them to hang up.

When the situation is reversed (I am running ppp and my father started
dialing under windows), if he stops the dialer quickly enough after
hearing the noise on the line --- if he stops it before it starts
dialing, he can usually get out without disrupting my ppp link.  I
can't do this in linux because poff takes a while to stop things
whereas under windows you can stop immediately.

The point then is, that in my experience, it might be possible to
listen to the line without disrupting the other link.  The other
evidence in favour of this is that I can pick up a normal phone,
listen to the link, and then put it down again --- without disrupting
the ppp link.  (Of course you have to keep quiet.)

Oh, and I tested out my idea for a script by using minicom.  First I
did
       atm2
       OK
but I couldn't hear anything.  Then I did
       ato
       ERROR
and also tried
       ato0
       ERROR
My guess is because I hadn't actually connected anywhere via the modem,
I couldn't actually go online.  Anyway, I haven't been able to find a way
to listen to the line.

Actually, perhaps I could try
       atd
without actually specifying a number.  I wonder if this would work??
       

> Some sort of "line in use" indicator would be better.

I presume you mean a hardware "led indicator" or something like that?
I could do that, though I'd prefer a software solution if there is
one.  

(And I am also curious as to why the  ABORT "NO DIALTONE" doesn't seem
to work --- I always thought it did abort, but just took its time
about doing so --- ie only after it had dialed the number and waited
a while.  But from what Bud Rogers has said, it would seem the abort
should happen straight away.)

Cheers,

Mark.



_/~~~~~~~~\___/~~~~~~\____________________________________________________
____/~~\_____/~~\__/~~\__________________________Mark_Phillips____________
____/~~\_____/~~\________________________________mark@ist.flinders.edu.au_
____/~~\HE___/~~\__/~~\APTAIN_____________________________________________
____/~~\______/~~~~~~\____________________________________________________
__________________________________________________________________________
        "They told me I was gullible ... and I believed them!"