Page 334 - Asterisk™: The Future of Telephony

"This is a test of Cepstral")
exten => 125,3,Playback(/tmp/swift)
exten => 125,4,System(rm /tmp/swift.wav)
exten => 125,5,Hangup()

Call Files

Call files allow you to create calls through the Linux shell. These powerful events are
triggered by depositing a .call file in the directory /var/spool/asterisk/outgoing/. The
actual name of the file does not matter, but it’s good form to give the file a meaningful
name and to end the filename with .call.

When a call file appears in the outgoing folder, Asterisk will almost immediatelyact on
the instructions contained therein. †
Call files are formatted in the following manner. First, we define where we want to call:
Channel: channel
We can control how long to wait for a call to be answered (the default is 45 seconds),
how long to wait between call retries, and the maximum number of retries. If
MaxRetries is omitted, the call will be attempted only once:
WaitTime: number
RetryTime: number
MaxRetries: number
If the call is answered, we specify where to connect it here:
Context: context-name
Extension: ext
Priority: priority
Alternatively, we can specify a single application and pass arguments to it:

Application: Playback()
Data: hello-world
Next, we set the Caller ID of the outgoing call:
CallerID: Asterisk 800-555-1212
Then we set channel variables, as follows:
SetVar: john=Zap/1/5551212
SetVar: sally=SIP/1000
and add a CDR account code:
Account: documentation

† We’re talking within milliseconds here. Don’t believe us? Try it for yourself!

306 | Chapter 14: Potpourri