Yes, I have looked at graphing.c and .h and I can't seem to find anything that would
allow for saving a graph as a .png file. If you create a graphing using graphing.c you can
not even save it manually by clicking on the graph(like you can if you use the gui
directly and not use the api.). gpt_control in the gui folder seems to handle saving the
plot as a png.
Also, what is a gpointer? I can't seem to find that any were, is it from a different
library that gretl uses?
in gpt_contol. c -> void save_graph_to_file (gpointer data, const char *fname)