AppendCDRUserField() — Appends a value to the user field of the Call Detail Record
Appends value to the user field
of the Call Detail Record (CDR). The user field is often used to store
arbitrary data about the call, which may not be appropriate for any of
the other fields:
; set the user field to 'abcde'
exten => 123,1,SetCDRUserField(abcde)
; now append 'xyz'
exten => 123,1,AppendCDRUserField(xyz)
This application has been deprecated in favor of the CDR function.
exten => 123,1,Set(CDR(userfield)=${CDR(userfield)}12345)