[Asterisk-Users] Seize phone line

[Jay Milk]

Joe Pukepail wrote:
> I have a question, we have some locations were I'm just planning on 
> putting in a PRI, management also wants analog lines incase the PRI is 
> down and someone calls 911.  Is there a way to use asterisk to seize a 
> phone line from the fax machine? 
>  
>  I don't want to have to have an analog line that only gets used in 
> the very rare situation with the PRI being down and someone needed to 
> dial 911 (other incoming and outgoing calls would be routed over a 
> private T1 to another location), but I don't want to just tap into the 
> fax line because there is a chance that someone could be sending or 
> receiving a fax at the same time.
[dial911]
exten => 911,1,ChanIsAvail(${TRUNK_FAX})
exten => 911,2,Dial(${TRUNK_FAX}/911)
exten => 911,3,Hangup
exten => 911,102,SoftHangup(${TRUNK_FAX})
exten => 911,103,Wait(1)
exten => 911,104,Goto(1)

adapted from a wiki page.