Midisend is a small application that will allow you to send midi events from
the shell. It will register as client like all other applications. The most
simple way to use it is to do
% midisend -f /dev/midi00 |
which will achieve about the same as adding a system midi port in artscontrol
(not quite, because midisend only sends events). The difference is that it is
easy for instance to start midisend on different computers (and like that,
use network transparency). It is also possible to make midisend send data from
stdin, which you can use to pipe data from non-aRts-aware applications to aRts,
like this
% applicationwhichproducesmidieventsonstdout | midisend -f - |