# Variables

If the channel has a CDR, that CDR has its own set of variables which can be accessed just like channel variables. The following builtin variables are available.

    ${CDR(clid)}         Caller ID
    ${CDR(src)}          Source
    ${CDR(dst)}          Destination
    ${CDR(dcontext)}     Destination context
    ${CDR(channel)}      Channel name
    ${CDR(dstchannel)}   Destination channel
    ${CDR(lastapp)}      Last app executed
    ${CDR(lastdata)}     Last app's arguments
    ${CDR(start)}        Time the call started.
    ${CDR(answer)}       Time the call was answered.
    ${CDR(end)}          Time the call ended.
    ${CDR(duration)}     Duration of the call.
    ${CDR(billsec)}      Duration of the call once it was answered.
    ${CDR(disposition)}  ANSWERED, NO ANSWER, BUSY
    ${CDR(amaflags)}     DOCUMENTATION, BILL, IGNORE etc
    ${CDR(accountcode)}  The channel's account code.
    ${CDR(uniqueid)}     The channel's unique id.
    ${CDR(userfield)}    The channels uses specified field.

In addition, you can set your own extra variables by using Set(CDR(name)=value). These variables can be output into a text-format CDR by using the cdr_custom CDR driver; see the cdr_custom.conf.sample file in the configs directory for an example of how to do this.