Well I can give you an answer for Linux test-mode...
Here is an example script from my system of an actual game..
Code:
nohup nice dom3 --era 2 -g Warhammergoons --port 28911 -STddd \
--statfile --scoredump -q --hours 48 \
--preexec /home/domgames/dominions3/savedgames/Warhammergoons/pre.sh \
--postexec /home/domgames/dominions3/savedgames/Warhammergoons/post.sh \
--renaming --hofsize 15 \
--enablemod Expanded_Nations_1_v1_02.dm --masterpass xxxxxx \
--mapfile Streamlands_8P_warhammer.map \
>/home/domgames/dominions3/savedgames/Warhammergoons/game.log \
2>/home/domgames/dominions3/savedgames/Warhammergoons/game.err &
Some of the non-Dom3 elements are
nohup: No Hangup command so I can log off without the game dying
nice: so it doesnt hog the CPU
&: the ampersand at the very end of the script is what tells it to run in background
a common error is running it & (background) but forgetting nohup (no hangup) so when you logoff, it dies