Xguirpc has the same options as xgui. Additionally there is one more option:
-force:
The force option is instructing xguirpc to
delete the portmap number of an old xguirpc. This option is only
necessary if an xguirpc was not terminated correctly on the
machine. Only the last registered xguirpc will receive messages
from the simulator kernel. This implies that a user can run only one
xguirpc on a computer.