a quick question regarding gr_block::history() etc.
Say I’ve called set_history(2) in the constructor and
my work function pointers look like this:
gr_complex const *in = (const gr_complex *) input_items;
gr_complex *out = (gr_complex *) output_items;
What does “in” point to? Is the item “in” points to already processed,
as the name history suggests? Or does it just assure that there are at
2 items in “input_items”?