[asterisk-users] Called number as variable - how to?

[Michael]

I want to obtained the called number (aka DID) as a variable. How is this 
done?

(Upline connectivity is via SIP provider).

With verbose = 100, the called number is clearly shown as 
follows "Wait("SIP/[called number]-64e6", "1")" for example, but I can't find 
the info as to how to get it as a variable.

Michael