maxima plot options gnuplot_out_file



Im curious to find out whether there is a way to set the gnuplot_out_file
variable to some function that returns a unique string , currently i have a
line in my  .maxima/maxima-init.mac  like this:

set_plot_option ([gnuplot_out_file,"./tmp/myplot.jpeg"])$

is it possible to change that to a function that generates a new unique
name each time? i'd like not to have to  type a name for an image file, so
its some unique random string for each plot image whenever i plot, this
important when i plot more than one graph at a time.
regards
Jiun