In Linux the ditty settings are "sticky" until overwritten or the system is rebooted.
For port configuration on the Linux host, there is a file you can create to issue the ditty commands at startup. Simply create and add your ditty commands to:
For example: vi /usr/bin/dgrp/config/ditty.commands
ditty-rp ctspace rtspace -ixon -ixoff -ixany 38400 ttyx##
Where ttyx## refers to the actual tty device name on your system.
This will result in hardware flow control and a baud rate setting of 38400 on boot up.