Invoking the Chat Script
You call chat scripts by using the connect option.
You can use connect "chat ..." in any PPP configuration
file or on the command line.
Chat scripts are not executable, but the program that is invoked
by connect must be executable. You might use the
chat utility as the program to be invoked by connect.
In this instance, if you store the chat script in an external file
through the –f option, then your chat script file
is not executable.
The chat program
that is described in chat(1m) executes the actual
chat script. The pppd daemon invokes the chat program whenever pppd encounters the connect "chat ..." option.
Note - You can use any external program, such as Perl or Tcl, to create advanced chat scripts. The chat utility
is provided as a convenience.