Hook to nm_keyfile_read().
The callee may abort the reading by setting an error via nm_keyfile_handler_data_fail_with_error().
the #GKeyFile that is currently read
the #NMConnection that is being constructed.
the %NMKeyfileHandlerType that indicates which type the request is.
the #NMKeyfileHandlerData. What you can do with it depends on the handler_type.
handler_type
Hook to nm_keyfile_read().
The callee may abort the reading by setting an error via nm_keyfile_handler_data_fail_with_error().