; In the [global] section of extensions.conf add

LIMIT_RTCC_INTERVAL=5000

LIMIT_RTCC_APP=Log(NOTICE|$
LIMIT_RTCC_APP=${LIMIT_RTCC_APP}{EXTEN},$
LIMIT_RTCC_APP=${LIMIT_RTCC_APP}{UNIQUEID},$
LIMIT_RTCC_APP=${LIMIT_RTCC_APP}{RAND()})

; then in section [default] or other

exten => AnswerAndWait,1,Wait(10)
exten => AnswerAndWait,2,Answer()
exten => AnswerAndWait,3,Wait(10)
exten => AnswerAndWait,4,Goto(3)

exten => 12345,1,SET(CALL_LIMIT=90000)
exten => 12345,n,Dial(Local/AnswerAndWait@default||rL(${CALL_LIMIT}:30000:2000))	; Or any other values

; By dialing 12345 you will hear ringing for 10sec then the call will be answered and each 5sec you will get a message with a new RAND() value each time and each 10sec you will see the new loop of AnswerAndWait
; If you update the CALL_LIMIT variable via Manager or your own LIMIT_RTCC_APP application, the call limit will be updated too.
; If your verbosity level is more than 10 - you will see some output from the app processing.
; You can not execute application or use a function, that starts autoservice on the channel like System() or CURL(), because it is allready in a call.
; To call a webpage it is possible to use an AGI script.
; For using an AGI script in [global] section (or on the calling channel before Dial) change the LIMIT_RTCC_APP to "AGI(GetLIMIT)"
; If you set LIMIT_RTCC_APP as:

LIMIT_RTCC_APP=AGI(GetLIMIT|$
LIMIT_RTCC_APP=${LIMIT_RTCC_APP}{UNIQUEID})

; your GetLIMIT AGI could be as simple as:

#!/bin/sh
RES=`wget "http://127.0.0.1/GetCallLimit.php?call=${1}" -O -`
echo "SET VARIABLE CALL_LIMIT ${RES}"

; and then you may also call it for the initial call limit by replacing
;exten => 12345,1,SET(CALL_LIMIT=90000)
; with
exten => 12345,1,EXEC(${LIMIT_RTCC_APP})