default plot to file settings



I was going through the docs looking for a way to instruct maxima to always
plot to file as a rule, is this possible to configure?
how does the plotting system work? is there some configuration that i can
place in the runtime environment  (maxima-init.mac)  to achieve my
objective?
the system command seems to offer some hope, but i dont know how it
interacts with the plotter (and i dont understand it a whole lot)
http://maxima.sourceforge.net/docs/manual/en/maxima_32.html#system