[App_rpt-users] Understanding ilink,9 usage

[larry]

Recently I installed a Dial version on a RPi2

In it includes command to use ilink,9 to send a text message to another 
node.
I am unable to find additional info about ilink,9 and how it works.

Could someone give me an explanation if how to utilize it?
Also what if anything needs to be pre-configured locally or at the 
receiving node to use this function.

A command syntax example would be nice as I am confused by the comment 
following the defined DTMF of 809
Rpt.conf defines ....  809 = ilink,9           ; Send Text Message 
(9,<destnodeno or 0 (for all)>,Message Text, etc.

Thanks

Larry - N7FM