The unixplot driver produces device-independent output in the GNU plot graphics language. The default size of the PostScript results generated by "plot2ps" is 5 x 3 inches; this can be increased up to about 8.25 x 8.25 by set size.
Syntax:
set terminal unixplot {"<fontname>"} {<fontsize>}
which defaults to 10-point "Courier".
There is a non-GNU version of the unixplot driver which cannot be compiled unless this version is left out.