[asterisk-users] If caller id is null set to a specific number

[Eric "ManxPower" Wieling]

Doug Lytle wrote:
> Jon Weisman wrote:
>> All,
>>  
>> If someone calls into my asterisk box and has a private number I would 
>> like to set the callers id to a specific telephone number, only when 
>> the ANI is missing, otherwise if present just pass it along. Any ideas?
> 
> [incoming]
> 
> exten => s,1,Gosubif($["${CALLERID(number)}" = "" ]?set-cid,s,1:2)
> 
> [set-cid]
> 
> exten => s,1,Set(CALLERID(number)=5551212)
> exten => s,n,Return()

ANI is not Caller*ID.  A caller can block their Caller*ID, but not their 
ANI.

It is CALLERID(num), not CALLERID(number)

In 1.2+ you can do it as (all one line):

exten => s,1,ExecIf($["${CALLERID(num)}" = ""],Set,CALLERID(num)=4055551212)

OR

exten => s,1,ExecIf($[${LEN(${CALLERID(num)})} = 
0],Set,CALLERID(num)=4055551212)