Hell, I need to plot points out of my c++ application. So I simply save my points to a points.txt and then run system("gnuplot 'plotmakro'"); which contains:
set output 'plot.png'
set terminal png
set grid
set multiplot
plot pointsa.txt' ', 'pointb.txt'
Is there a solution so that I get plot2.png, plot3.png when running the makro again?